TW201726396A - Adhesive sheet and method for producing adhesive sheet - Google Patents

Abstract

Disclosed is an adhesive sheet comprising a resin layer on a base material or a release material, wherein at least a surface ([alpha]) of the resin layer on the opposite side from the side where the base material or the release material is provided has adhesive properties. The surface ([alpha]) of the resin layer has: recesses; and at least one flat surface (f1) having an area in which a range surrounded by a 100-[mu]m-dia. circle can be selected as observed from the surface ([alpha]) side. The shape of the flat surface is indefinite.

Description

Adhesive sheet and adhesive sheet manufacturing method

The present invention relates to a method of manufacturing an adhesive sheet and an adhesive sheet.

A general adhesive sheet is composed of a substrate, an adhesive layer formed on the substrate, and a release material provided on the adhesive layer as needed. When used, when the release material is provided, the adhesive sheet is peeled off. The release material abuts the adhesive layer against the adherend and attaches it.

However, it will be used for example for identification. When the adhesive sheet having a large attachment area such as a decorative surface, a decorative cover, a metal plate, or the like is attached to the adherend, air is easily accumulated between the adhesive layer and the adherend, and the portion is easily accumulated. It becomes a problem of "swelling up", and there is a problem that the adhesive sheet is not easy to attach to the adherend.

In order to solve such problems, for example, Patent Document 1 discloses that a surface of an adhesive layer is in contact with a release material having a fine emboss pattern, and a groove of a specific shape is manually disposed on a surface of the adhesive layer in a specific pattern. Adhesive sheets.

By using these adhesive sheets, it occurs when attached to the adherend "Air accumulation" can be released to the outside through a groove formed by the surface of the adhesive layer.

[Previous Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Publication No. 2001-507732

However, as described in Patent Document 1, etc., an adhesive sheet having an adhesive layer of a groove of a generally specific shape is arranged in a specific pattern, and if the width of the groove is narrow, air is not easily removed, and if the width of the groove is large, not only the surface is affected by the surface. The substrate is recessed to deteriorate the appearance, and there is also a problem that the adhesion is lowered.

Further, since the adhesive sheet is provided with a groove in a specific pattern, the adhesive force at the portion where the groove is disposed is partially deteriorated, and when the adhesive sheet is attached to the adherend, there is a possibility that peeling occurs from the portion.

On the other hand, when the adhesive sheet is attached to the adherend and then peeled off, since the adhesive characteristics of the adhesive sheet are partially different, depending on the peeling direction of the adhesive sheet, residual adhesive is generated in the adherend. Hey. For example, when the adhesive sheet having the adhesive layer of the groove is arranged in a lattice shape, if it is peeled off in an oblique direction, there is a possibility that a residual paste is generated in the adherend.

Further, when the adhesive sheet is subjected to press working, the pattern of the groove arrangement pattern and the pattern of the press working are overlapped. In this case, there is a problem that the depth of the cut is deviated, and it is impossible to form a cut or the like on the adhesive sheet.

And, in general, in order to make the stripping material provided on the adhesive sheet It is easy to peel off, and a step of applying a cut-off only to the peeling material and setting a peeling starting point (so-called ridge processing) is sometimes performed. When this step is carried out, the release material is usually peeled off from the adhesive sheet, and after the cut material is cut, the release material and the adhesive layer of the adhesive sheet are laminated again.

However, since the adhesive sheet described in Patent Document 1 uses an embossed liner as the release material, when the release material and the adhesive layer are laminated again, since it is difficult to follow the embossing pattern of the release material, it is necessary to prepare for the adhesive sheet. Apply another stripping material to the embossing process.

Further, in Patent Document 1, in order to form a fine structure on the adhesive layer, a method of laminating the adhesive layer and the substrate after applying an adhesive to the embossed pad to form an adhesive layer is used (so-called Transfer coating method). However, when a substrate having a low-polar surface such as a polyolefin-based substrate is used as the above-mentioned substrate, sufficient adhesion cannot be obtained at the interface between the substrate and the adhesive layer by this method.

Further, unlike the release material made of paper, it is difficult to form a fine embossing pattern for the adhesive layer by the release material made of the resin film.

An object of the present invention is to provide an adhesive sheet which is excellent in degassing property and which has excellent adhesive properties, which can be easily removed when attached to an adherend, and a method for producing the adhesive sheet.

The inventors have found that the following adhesive sheet can solve the above problems, and thus the present invention is completed, and the adhesive sheet has an adhesive surface. There is a resin layer having a concave portion and at least one flat surface, and the flat surface has a width which is selected by a circle having a diameter of 100 μm by observation from the surface side, and the shape of the flat surface is amorphous .

That is, the present invention provides the following [1] to [19].

[1] An adhesive sheet having a resin layer on a substrate or a release material, and having adhesion at least on a surface (α) of the resin layer which is an opposite side to a side on which the substrate or the release material is provided. The adhesive sheet has a concave portion and one or more flat surfaces (f1) on the surface (α) of the resin layer, and the flat surface (f1) has a circle selected from a diameter of 100 μm by observation from the surface (α) side. The breadth of the enclosed area, and the shape of the flat surface is amorphous.

[2] The adhesive sheet according to the above [1], wherein the surface (α) of the resin layer has one or more flat surfaces (f2) having an area of 0.2 mm ² or more.

[3] The adhesive sheet according to the above [1] or [2], wherein in the arbitrarily selected region (D) of 8 mm in length × 10 mm in width on the surface (α), there is an area relative to the region (D) The total area of the recess is 100%, and there is a recess having an area of 70 to 99.99%.

[4] The adhesive sheet according to any one of the above [1] to [3] wherein, in the arbitrarily selected region (D) of 8 mm long by 10 mm wide on the surface (α), there is a plurality of flat And removing one or more flat surfaces (S) obtained by adding a flat surface having a cumulative relative number of 30% or less from the relative surface of the plurality of flat surfaces having the smaller number of the plurality of faces, and the respective surfaces are opposite to each other The skewness Sk of the normal distribution curve of the frequency is 1.0 or more.

[5] The adhesive sheet according to the above [4], wherein the kurtosis Ku value of each of the one or more flat surfaces (S) with respect to the normal distribution curve of the area and the frequency is 1.8 or more.

[6] The adhesive sheet according to any one of [1] to [5] wherein the flat surface is present in a plurality of surfaces (α), and a position of the plurality of flat surfaces does not have a periodicity.

[7] The adhesive sheet according to any one of [1] to [6] wherein the concave portion has a height difference of at most 0.5 μm or more.

[8] The adhesive sheet according to any one of [1] to [7] wherein the concave portion is not formed by using a release material having an emboss pattern.

[9] The adhesive sheet according to any one of the above [1], wherein the resin layer comprises: a resin-containing resin portion (X) as a main component, and a fine particle portion composed of fine particles (Y) ).

[10] The adhesive sheet according to the above [9], wherein the mass retention rate after heating the resin layer at 800 ° C for 30 minutes is 3 to 90% by mass.

[11] The adhesive sheet according to the above [9] or [10] wherein the resin contained in the resin portion (X) contains an adhesive resin.

[12] The adhesive sheet according to any one of the above [9], wherein the resin portion (X) further contains one or more selected from the group consisting of a metal chelate crosslinking agent and an epoxy crosslinking agent. .

[13] The adhesive sheet according to any one of the above [9], wherein the fine particles are one or more selected from the group consisting of cerium oxide particles, oxidized metal particles, and bentonite.

[14] The adhesive sheet according to any one of [9] to [13] above, wherein The surface (β) of the aforementioned resin layer on the side where the substrate or the release material is placed has adhesiveness.

[15] The adhesive sheet according to any one of [1] to [14] wherein the resin layer is from the side on which the substrate or the release material is provided, according to the layer (X?) mainly containing the resin portion (X). A multilayer structure in which a layer (Y1) having a particle portion (Y) of 15% by mass or more and a layer (Xα) mainly containing a resin portion (X) are laminated in this order.

[16] The adhesive sheet according to the above [15], wherein the layer (Xβ) is a layer formed of a composition (xβ) containing a resin and having a content of fine particles of less than 15% by mass, and the layer (Y1) is composed of microparticles. A layer formed of a composition (y) of 15% by mass or more, and a layer (Xα) is a layer formed of a composition (xα) containing a resin and having a content of fine particles of less than 15% by mass.

[17] A method of producing an adhesive sheet, which is the method of producing the adhesive sheet according to any one of [1] to [16] above, and has at least the following steps (1) and (2): Step (1) a coating film (x') composed of a composition (x) containing a resin and having a content of fine particles of less than 15% by mass, and a coating film comprising a composition (y) containing 15% by mass or more of fine particles ( Step y'); Step (2): a step of drying the coating film (x') and the coating film (y') formed in the step (1) at the same time.

[18] A method of manufacturing an adhesive sheet, which is manufactured as described above [17] a method of adhering a sheet, and having at least the following steps (1A) and (2A): step (1A): on a substrate or a release material, according to a composition comprising a resin and having a content of fine particles of less than 15% by mass ( a coating film (xβ') composed of xβ), a coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles, and a content of the fine particles containing less than 15% by mass of the resin. a step of laminating and forming a coating film (xα') composed of the composition (xα); and (2A): simultaneously applying a coating film (xβ') formed by the step (1A), and a coating film (y' And the step of drying the coating film (xα').

[19] A method for producing an adhesive sheet, which is a method for producing an adhesive sheet according to the above [17], and has at least the following steps (1B) and (2B): Step (1B): being disposed on a substrate or peeling off In the layer (Xβ) mainly containing the resin portion (X), the coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles, and the content of the microparticles containing the resin a step of laminating a coating film (xα') composed of a composition (xα) of less than 15% by mass; and a step (2B): simultaneously forming a coating film (y') formed by the step (1B) And the step of drying the coating film (xα').

When the adhesive sheet of the present invention is attached to the adherend, it can easily remove the air which may be generated and has excellent deaeration property and adhesion. The characteristics are also good.

1a, 11a, 12a, 1b, 2a, 2b‧‧‧ adhesive sheets

11‧‧‧Substrate

12‧‧‧ resin layer

12a‧‧‧Surface (α)

12b‧‧‧Surface (β)

(X)‧‧‧Resin part (X)

(Y)‧‧‧Parts of particles (Y)

(Xβ)‧‧‧ mainly consists of the layer of the resin part (X) (Xβ)

(Xα)‧‧‧ mainly consists of the layer of the resin part (X) (Xα)

(Y1) ‧ ‧ layers containing more than 15% by mass of the particle fraction (Y) (Y1)

13, 13a, 131, 132‧‧ ‧ recess

14‧‧‧flat surface

15‧‧‧ convex

21, 22‧‧‧ peeling material

100‧‧‧Transmissive adherend

100a‧‧‧ smooth surface

101‧‧‧Adhesive body

Fig. 1 is a schematic cross-sectional view showing the adhesive sheet of an example of the structure of the adhesive sheet of the present invention.

Fig. 2 is a schematic plan view showing the surface (α) when viewed from the surface (α) side of the resin layer of the adhesive sheet of the present invention.

Fig. 3 is a schematic cross-sectional view showing the resin layer as an example of the shape of the surface (α) side of the resin layer of the adhesive sheet of the present invention.

Fig. 4 is a schematic cross-sectional view showing an example of a measurement sample for observing a concave portion and a flat surface from the surface (α) side of the resin layer defined by the present invention.

Fig. 5(a) is a view showing an exposed surface (α) of an adhesive layer of the adhesive sheet prepared in Example 1 from the surface (α) side by an arbitrarily selected microscope (D) having a length of 8 mm × a width of 10 mm. Binarized image of the resulting image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion. Fig. 5(b) is a cross-sectional image obtained by observing the cross section of the adhesive sheet prepared in Example 1 using a scanning microscope.

Fig. 6 is a view showing a region (D) of an exposed surface (α) of a resin layer of the adhesive sheet prepared in Example 2, which is surrounded by a rectangular shape of a length of 8 mm × a width of 10 mm, which is selected from the surface (α) side by a digital microscope. Like a binary image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion.

Fig. 7 is a view showing a region (D) of an exposed surface (α) of a resin layer of the adhesive sheet prepared in Example 3, which is surrounded by a rectangular shape of an arbitrarily selected length of 8 mm × a width of 10 mm, from the surface (α) side using a digital microscope. Like a binary image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion.

Fig. 8 is a view showing a region (D) of an exposed surface (α) of a resin layer of the adhesive sheet prepared in Example 4 taken from a surface (α) of an arbitrarily selected length of 8 mm × a width of 10 mm from a surface (α) side using a digital microscope. Like a binary image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion.

Fig. 9 is a view showing the exposed surface (α) of the resin layer of the adhesive sheet prepared in Comparative Example 1 from the surface (α) side by a digital microscope, surrounded by an arbitrarily selected area (D) of a length of 8 mm × a width of 10 mm. Like a binary image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion.

Fig. 10 is a view showing a region (D) of an exposed surface (α) of a resin layer of the adhesive sheet prepared in Comparative Example 2, which is surrounded by a rectangular shape of a length of 8 mm × a width of 10 mm, which is selected from the surface (α) side by a digital microscope. Like a binary image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion.

Fig. 11 is a view showing a region (D) of an exposed surface (α) of a resin layer of the adhesive sheet prepared in Comparative Example 3, which is surrounded by a rectangular shape of a length of 8 mm × a width of 10 mm, which is selected from the surface (α) side by a digital microscope. Like a binary image. Moreover, the black portion of the binary image is equivalent to a flat Tan, the white part is equivalent to the recess.

Fig. 12 is a view showing a region (D) of an exposed surface (α) of a resin layer of the adhesive sheet prepared in Comparative Example 4, which is surrounded by a rectangular shape of a length of 8 mm × a width of 10 mm, which is selected from the surface (α) side by a digital microscope. Like a binary image. Further, the black portion of the binarized image corresponds to a flat surface, and the white portion corresponds to a concave portion.

In the present invention, for example, "the YY containing the XX component as the main component" or the "YY mainly composed of the XX component" means that "the component having the highest content among the components contained in YY is the XX component". The content of the specific XX component described in the above is usually 50% by mass or more, preferably 65 to 100% by mass, more preferably 75 to 100% by mass, even more preferably the total amount (100% by mass) of YY. 85~100% by mass.

In the present invention, for example, "(meth)acrylic acid" means both "acrylic acid" and "methacrylic acid", and other similar terms are also the same.

Further, in the case of a preferred numerical range (for example, a range of contents, etc.), the lower limit and the upper limit of the step are described as being independently combinable. For example, based on the description of "better 10 to 90, more preferably 30 to 60", it is also possible to combine "better lower limit (10)" and "better upper limit (60)" to become "10~60". "."

[Composition of the adhesive sheet of the present invention]

The adhesive sheet of the present invention has a resin layer on a substrate or a release material. Further, at least on the side (α) of the resin layer on the side opposite to the side on which the substrate or the release material is provided, there is an adhesive sheet having a concave portion and a flat surface on the surface (α).

Fig. 1 is a schematic cross-sectional view showing the adhesive sheet of an example of the structure of the adhesive sheet of the present invention.

The adhesive sheet as in the state of the present invention is exemplified by, for example, an adhesive sheet 1a having a resin layer 12 on a substrate 11 as shown in Fig. 1(a), or a release sheet 21 as shown in Fig. 1(b). The adhesive sheet 1b having the resin layer 12 is placed thereon.

The adhesive sheet of the present invention has adhesiveness at least on the surface (α) 12a (hereinafter also referred to as "surface (α)") of the resin layer 12 which is the opposite side to the side on which the substrate 11 or the release material 21 is provided, and has a concave portion. 13 and flat surface 14.

Therefore, from the viewpoint of handleability, the adhesive sheet which is another aspect of the present invention preferably has peeling on the surface (α) 12a of the resin layer 12 with respect to the adhesive sheets 1a and 1b shown in Fig. 1 . The material 22 is a member of the adhesive sheets 2a and 2b as shown in Fig. 1 (c) or (d).

Further, in the adhesive sheet of the same state of the present invention, as shown in Fig. 1, the resin layer 12 preferably contains a resin-containing resin portion (X) and a particle portion (Y) composed of fine particles.

By containing the particle portion (Y) in the resin layer 12, the shape retainability after adhesion can be improved, and when the obtained adhesive sheet is used at a high temperature, the adhesive sheet having improved burst resistance can be obtained.

Details of the resin portion (X) and the particle portion (Y) will be described later.

Further, in the adhesive sheet of the same state of the present invention, the surface (β) 12b (hereinafter also referred to as "surface (β)") of the resin layer 12 on the side where the substrate 11 or the release material 21 is provided may have adhesiveness. .

By making the surface (β) also adhesive, the adhesion between the resin layer 12 and the substrate 11 is good according to the adhesive sheets 1a and 2a shown in Figs. 1(a) and (c), according to Fig. 1(b) The adhesive sheets 1b and 2b shown in (d) can be double-sided adhesive sheets.

[Requirements on the concave and flat surfaces of the surface (α)]

In the adhesive sheet of the present invention, as shown in Figs. 1(a) to 1(d), the concave portion 13 and the flat surface 14 are present on the surface (α) 12a of the resin layer 12.

The concave portion 13 present on the surface (α) is used as an air discharge passage for releasing the "air accumulation" generated when the surface (α) of the resin layer of the adhesive sheet of the present invention is attached to the adherend to the outside. The role of the person.

On the other hand, when the flat surface 14 of the surface (α) is bonded to the adherend, the surface which is in direct contact with the adherend and adheres to the adhesive sheet affects the adhesive force of the adhesive sheet.

Fig. 2 is a schematic plan view showing the surface (α) when viewed from the surface (α) side of the resin layer of the adhesive sheet of the present invention.

The concave portion existing on the surface (α) of the resin layer, as shown in Fig. 2, is preferably an amorphous concave portion 13, but a concave portion may be formed.

However, in the same state of the present invention, as shown in Fig. 2, it is preferable that one or more amorphous recesses 13 are present on the surface (α) 12a of the resin layer 12. There are a plurality of amorphous recesses 13.

By the presence of the amorphous recess in the surface (α) of the resin layer, it is possible to form an adhesive sheet in which the deaeration property and the adhesive property are improved in a well-balanced manner.

Further, in the case where a plurality of amorphous recesses are present, even if a portion of the concave portion in which the surface (α) exists is collapsed by applying pressure from a certain direction, the concave portion 13 having a shape maintained is easily present on the surface (α). Can prevent the path of degassing from disappearing.

Further, the length of the concave portion 13 when viewed from the concave portion 13 of the surface (α) is not particularly limited. That is, the recess 13 includes a relatively long groove shape or a relatively short concave shape.

Further, it is present on the flat surface of the surface (α) of the resin layer 12, and as shown in Fig. 2, it is preferably an amorphous flat surface 14. However, there may also be a flat surface that is shaped.

However, in the same state of the present invention, as shown in Fig. 2, the shape of the flat surface 14 which is preferably observed on the surface (?) 12a side of the resin layer 12 is amorphous, and preferably one or more amorphous flat surfaces are present. 14. There is preferably a plurality of amorphous recesses 13.

Further, the flat surface present on the surface (α) of the resin layer may be provided with a fixed flat surface together with the amorphous flat surface 14.

By the presence of an amorphous flat surface on the surface (α) of the resin layer, unlike the surface of the adhesive layer formed using a release sheet having an embossed pattern, a portion having a weak local adhesion or a portion having a poor deaeration property can be used. The existence is as small as possible. As a result, the surface of the resin layer (α) exhibits excellent degassing properties and adhesion characteristics.

In the present invention, the term "amorphous" refers to a shape in which a pattern or a polygon such as a circle or an ellipse, which can be centered, is used, and the shape is irregular, and the shape is not similar in shape. Specifically, it corresponds to the shape of the concave portion 13 and the flat surface 14 shown in Fig. 2 .

On the other hand, as a person who is not "amorphous" but "set", for example, a circle, an ellipse, a polygon, or the like. In addition, in the present specification, the term "polygon" refers to a pattern in which the inside of the interior (not protruding to the outside) can be plotted as a diagonal, and the sum of the internal angles is 180 × n (degrees) (n is a natural number). A graphic surrounded by a straight line. The polygon also includes a shape in which the corner portion is curved in a curved shape.

Further, in the present invention, the judgment of whether or not the "unshaped" concave portion or the flat surface exists on the surface (α) of the resin layer is in principle from the surface (α) side of the resin layer, by a visual or digital microscope (magnification: 30 to 100) It is judged by observing the shape of the flat surface or the concave part of an observation object.

Further, when a digital microscope is used, for example, as shown in FIG. 4( a ), the focus is gradually moved from the surface (α) 12 a above the portion where the flat surface is visually recognized to the direction A, and the portion having the first focus is the flat surface. Observation is more appropriate.

Further, when the focus cannot be determined by the above method, as shown in Fig. 4 (b), the squeegee may be used to apply the smooth surface 100a to the surface (α) 12a of the resin layer as much as possible without load. The adhesive body 100 was observed on the surface (α) 12a of the resin layer through the light-transmitting adherend 100 from the W direction using a digital microscope to confirm whether or not a concave portion and a flat surface were present. The method is judged.

In other words, the portion of the surface (α) that is in contact with the smooth surface 100a can be determined as a "flat surface", and the portion of the surface (α) that is not in contact with the smooth surface 100a can be determined as a "concave portion".

However, it is also possible to select 1 to 10 regions of the region (D) of arbitrarily selected length 8 mm × width 10 mm on the surface (α), and a visual or digital microscope from the surface (α) side (magnification: 30 to 100 times) ) Observe and judge the shape of the concave or flat surface existing in each selected area (D). That is, in any of the selected regions, if there is an amorphous concave portion or a flat surface, it may be regarded as "a concave or flat surface having an amorphous surface (α)". Similarly, in any of the selected regions, if there are a plurality of amorphous recesses or flat surfaces, it can be regarded as "a plurality of amorphous recesses or flat surfaces on the surface (α)."

In the observation of the region (D), a digital microscope can also be used to observe the selected region (D) at a low magnification at a time.

Further, the selected region (D) can be observed at a high magnification using a digital microscope, but since the region (D) is observed at a high magnification, the imageable region of the digital microscope is larger. In this case, the image connection function of the digital microscope can also be used to capture an arbitrarily selected adjacent region and obtain a plurality of adjacent images, and the plurality of images can be connected to form a connected image, and the connected image can be arbitrarily selected. The portion surrounded by a rectangle having a length of 8 mm × a width of 10 mm is selected as the region (D) for the above judgment.

Further, in the following description, in order to determine whether or not a certain requirement is satisfied, a digital microscope is used to observe the selected region. It is possible to judge whether or not the requirement is satisfied from the self-joining image as described above.

In the description of the present specification, the digital microscope used for the observation of various shapes is, for example, a product name "digital microscope VHX-1000" or "digital microscope VHX-5000" manufactured by KYENCE Corporation.

Further, when observing various shapes, the surface (α) may be directly observed by a digital microscope at the above magnification, or an image may be obtained by using a digital microscope at the above magnification, and the concave portion and the flat surface displayed in the image may be visually observed. The method of the shape of the department.

Further, the shape of the concave portion in which the surface (α) exists is preferably visually recognized from the surface (α) side by visual observation.

Similarly, the amorphous flat surface shape in which the surface (α) exists is preferably visually recognized from the surface (α) side by visual observation.

Further, as shown in Fig. 1 (c) or (d), the exposed surface (α) of the adhesive sheet 2a, 2b in which the release material 22 is laminated on the surface (α) 12a of the resin layer 12 is removed. ) 12a becomes a visual observer.

In the same state of the present invention, on the surface (α), as shown in Fig. 2, a concave portion may be formed together with the concave portion 13 of the amorphous shape.

However, as the total area of the concave portion existing with respect to the surface (α) is 100%, the ratio of the area of the amorphous concave portion existing on the surface (α) is preferably 80 to 100%, more preferably 90 to 100%, and More preferably 95~100%, and even better 100%.

Further, in the same state of the present invention, as a ratio of the area occupied by the concave portion of the surface (α) as a total area of 100% with respect to the surface (α) Preferably, it is 10 to 80%, more preferably 20 to 70%, still more preferably 30 to 60%, and even more preferably 35 to 55%.

Similarly, in the same state of the present invention, on the surface (α), as shown in Fig. 2, a fixed flat surface may be present together with the amorphous flat surface 14.

However, as a total area of 100% of the flat surface existing on the surface (α), the ratio of the area of the amorphous flat surface present on the surface (α) is preferably from 80 to 100%, more preferably from 90 to 100%. It is better for 95~100%, and even better for 100%.

Further, in the same state of the present invention, the ratio of the area occupied by the flat surface of the surface (α) as a total area of 100% with respect to the surface (α) is preferably from 20 to 90%, more preferably from 30 to 80. %, better 40~70%, and even better 45~65%.

Moreover, the above-mentioned "area ratio of the area occupied by the concave portion or the flat surface" can be obtained by using a digital microscope (magnification: 30 to 100 times) to obtain an image of the surface (α), and image processing is performed on the image (binary processing) ) and calculate.

Further, an image of the region is obtained by using a digital microscope (magnification: 30 to 100 times) in 1 to 10 regions of the region (D) having an arbitrarily selected length of 8 mm × 10 mm on the surface (α). The image calculates the value of the "area ratio of the area occupied by the concave portion or the flat surface" of each region, and regards the average of the values of the selected one to ten regions as the surface (α) of the resin layer existing on the adhesive sheet to be the target. "The proportion of the area occupied by the concave or flat surface".

In the same manner as in the present invention, it is preferable that the shape of the concave portion and the flat surface which are preferably formed on the surface (α) of the resin layer is not obtained from the viewpoint of the adhesive sheet which is improved in various characteristics such as degassing or adhesive properties. The shape of the fixed repeating unit.

Further, in the same manner as in the present invention, it is preferable that a plurality of concave portions are present on the surface (α) of the resin layer, and the plurality of concave portions are used in view of the adhesive sheet which is improved in various characteristics such as degassing or adhesive properties. The location of existence does not have periodicity. Further, based on the same viewpoint, it is preferable that the surface (α) of the resin layer has a plurality of flat faces, and the existence position of the plurality of flat faces does not have periodicity.

In the present invention, the "position of the plurality of concave portions or the flat surface does not have periodicity" means that the surface of the resin layer (α) does not have the same repeating pattern in the surface (α) of the resin layer, but is irregular. (random) status.

Further, it is determined whether or not "the shape of the concave portion and the flat surface does not have a shape which is a fixed repeating unit", and whether or not "the position of the plurality of concave portions or the flat surface does not have a periodicity" is determined by the above-mentioned "in the resin layer" The method of judging whether or not the surface (α) has an amorphous concave portion or a flat surface is judged in the same manner.

Hereinafter, specific requirements for the concave portion and the flat surface in which the surface (α) exists will be described.

[Everything that the adhesive sheet of the present invention satisfies]

The adhesive sheet of the present invention, as shown in Figures 1(a) to (d), is in the tree The surface (α) 12a of the lipid layer 12 has a concave portion 13 and a flat surface 14, which are the following requirements (Ii) and (Iii). The observation from the surface (α) side of the resin layer means the surface (α) of the resin layer as viewed from the A direction side in Figs. 1 (a) and (b).

. Requirement (Ii): There are one or more flat faces (f1) having a diameter of 100 μm (preferably a diameter of 150 μm, more preferably by observation from the surface (α) side of the resin layer. The width of the area surrounded by a circle of 200 μm.

. Requirement (Iii): The shape of the flat surface is amorphous.

The concave portion 13 present on the surface (α) is used as an air discharge passage for releasing the "air accumulation" generated when the surface (α) of the resin layer of the adhesive sheet of the present invention is attached to the adherend to the outside. The role of the person.

On the other hand, when the flat surface 14 of the surface (α) of the resin layer is bonded to the adherend, the surface which is in direct contact with the adherend and adheres to the adhesive sheet affects the adhesive force of the adhesive sheet.

An adhesive sheet having an adhesive layer having a groove formed using a release sheet having a generally designed embossed pattern has, for example, a portion having a good deaeration property but a weak adhesive force, or a portion having an excellent adhesive property but a poor degassing property. .

An adhesive sheet having an adhesive layer having a groove formed by artificially preliminarily setting a shape, a width, a length, a number, a position, and the like is difficult to obtain characteristics such as deaeration property, appearance, adhesion property, and press workability. Balanced well, but due to the shape or number of grooves in the adhesive layer Etc., resulting in unevenness.

On the other hand, since the adhesive sheet of the present invention is formed on the surface (α) of the resin layer attached to the adherend surface of the adherend, the concave portion and the flat surface satisfying the above requirements (Ii) and (Iii) can be adhered. Various characteristics such as degassing property or adhesive property required for the sheet are improved in a well-balanced manner.

The details of the requirements (Ii) and (Iii) will be described below.

<Requirements (Ii)>

Fig. 2 is a schematic plan view showing the surface (α) when viewed from the surface (α) side of the resin layer of the adhesive sheet of the present invention.

Since the surface (α) has a flat surface (f1), the surface (α) can be sufficiently adhered to the adherend, so that the adhesion to the adherend can be improved, and the adhesion is higher. Adhesive sheets.

Further, in the above-described embodiment of the present invention, in the region (D) of arbitrarily selected length 8 mm × width 10 mm on the surface (α) of the resin layer, preferably one or more flat faces (f1) are present. There is a good number of flat faces (f1).

Further, in the above embodiment, it is not necessary that the flat surface existing on the surface (α) or the region (D) of the resin layer is the flat surface (f1) as long as it exists on the surface (α) or the region (D). The flat surface includes a flat surface (f1).

In the conventional adhesive sheet, if it is formed by drawing the adhesive layer and the roll for forming, a convex portion or a strip portion is formed on the surface. In the agent layer, it is difficult for the convex portion or the strip portion existing in the exposed surface to have a flat surface having a wide area which is selected to be surrounded by a circle having a diameter of 100 μm, since the contact or the line contact is followed by the adherend Therefore, there is a case where the adhesive property of the adherend is poor. Further, in the conventional adhesive sheet, in the case where the surface of the adhesive layer is processed by sand blasting, it is difficult to have a diameter of 100 μm in the region of the convex portion of the uneven shape formed on the exposed surface of the adhesive layer. The flat surface of the wide area surrounded by the circle is followed by the point contact and the adherend, so that the adhesive property to the adherend is poor.

The flat surface of the surface of the adhesive layer having the unevenness is fixed by the transfer of the embossed pattern of a specific shape by a general design, and the flat surface of the shape of the same shape is difficult to be repeated, or it is difficult to repeat the flat surface of the same shape. It is difficult to balance various characteristics such as self-adhesive properties, appearance, and press formability.

<Requirements (Iii)>

As shown in Fig. 2, the adhesive sheet of the present invention has a flat surface having an amorphous shape. A shaped flat surface may also be present on the surface (α) of the resin layer. The amorphous flat surface existing on the surface (α) of the resin layer may be a flat surface having a wide area which is selected to be surrounded by a circle having a diameter of 100 μm as viewed on the surface (α) side of the resin layer, or A flat surface other than the one. The judgment as to whether the shape of the flat surface is amorphous is judged by visual observation or a digital microscope (magnification: 30 to 100 times) from the surface (α) side of the resin layer to observe the surface (α) of the resin layer, specifically, meaning By way of example The result of the method evaluation described.

However, in the same state of the present invention, as shown in Fig. 2, it is preferable that one or more amorphous flat faces 14 are present on the surface (α) 12a of the resin layer 12, and a plurality of amorphous flat faces 14 are more preferable. .

By the presence of the amorphous recess in the surface (α) of the resin layer, it is possible to obtain an adhesive sheet in which the deaeration property and the adhesive property are improved in a well-balanced manner.

<Special requirements related to the flat surface of the surface (α)>

In the same state of the present invention, the flat surface in which the surface (α) exists satisfies the flat surfaces of the requirements (Ii) and (Iii), and further satisfies any of the following requirements (I-1) to (I-3).

. Requirement (I-1): One or more flat surfaces (f2) having an area of 0.2 mm ² or more (preferably 0.3 mm ² or more, more preferably 0.4 mm ² or more) are present on the surface (α) of the resin layer.

In the flat surface of the plurality of flat surfaces, one or more flat surfaces (S) obtained by adding a flat surface having a cumulative relative number of times from the smaller flat surface area to the relative number of times are included, and one flat surface (S) is included. The area of the above flat surface (S) preferably satisfies the following requirements (I-2) and/or (I-3).

. Requirement (I-2): The skewness Sk of each of the one or more flat faces (S) with respect to the normal distribution curve of the area and the frequency is 1.0 or more.

. Requirement (I-3): The kurtosis Ku value of each of the one or more flat faces (S) with respect to the normal distribution curve of the area and the frequency is 1.8 or more.

Further, the surface (α) or the surface (α) of the resin layer In the area (D) of the length of 8 mm × 10 mm, which is selected by the ideology, as long as there is a flat surface that satisfies any requirement of the element (I-1) to the element (I-3), if there are multiple repetitions satisfying the requirements (I) -1) The flat surface of any element of the requirement (I-3) is better.

By satisfying any of the requirements (I-1) to (I-3), it is possible to obtain an adhesive sheet in which various characteristics such as deaeration property and adhesive property are improved in a well-balanced manner.

<Requirement (I-1)>

In the same state of the present invention, it is preferred that one or more flat surfaces (f2) having an area of 0.2 mm ² or more (preferably 0.3 mm ² or more, more preferably 0.4 mm ² or more) are present on the surface (α) of the resin layer. More preferably, the flat surface (f2) exists.

Since the surface (α) has a flat surface (f2), the surface (α) can be sufficiently adhered to the adherend, so that the adhesion to the adherend can be improved, and the adhesion is higher. Adhesive sheets.

Further, in the above aspect of the invention, in the region (D) of arbitrarily selected length 8 mm × width 10 mm on the surface (α) of the resin layer, preferably one or more flat faces (f2) are preferable. There is a plurality of flat faces (f2).

Further, in the above embodiment, it is not necessary that the flat surface existing on the surface (α) or the region (D) of the resin layer is the flat surface (f2) as long as it exists on the surface (α) or the region (D). The flat surface includes a flat surface (f2).

Also, on the surface (α) or surface (α) of the resin layer In the region (D) of arbitrarily selected length 8 mm × width 10 mm, it is preferable to have one or more flat faces (f12) corresponding to both the flat surface (f1) and the flat surface (f2), and it is more preferable to have plural The flat surface (f12).

Further, in the present invention, whether or not the above-mentioned flat surfaces (f1), (f2), and (f12) are present in the surface (α) or the region (D) can be observed by using a digital microscope (magnification: 30 to 100 times). The flat surface of the surface (α) or the area (D) of the resin layer of the adhesive sheet of the object is taken, and an image is obtained. Based on the image, the image analysis software is used to determine whether or not the circle is surrounded by a circle having a diameter of 100 μm. Areas can be calculated for the area of the flat surface.

<flat surface (S)>

The "flat surface (S)" existing on the surface (α) of the resin layer refers to the cumulative relative amount of the relative number of times from the smaller area of each flat surface in the plurality of flat surfaces in which the area (D) exists. The remaining flat surface after the flat surface of 30% or less.

In the present invention, the reason for removing the "flat surface of 30% or less of the cumulative relative number of times from the area where each flat surface is smaller is added" is based on the following reason.

That is, when an image of an area (D) of an arbitrarily selected length of 8 mm × 10 mm is obtained by a digital microscope, the flat surface of the end portion of the impending area (D) is rectangular 4 of the boundary line of the area (D). The sides are cut off. The "cut flat surface" is changed depending on the region (D) selection mode, and is not a flat surface actually present on the surface (α).

In this way, when the flat surface cut by the four sides of the rectangle including the boundary line of the region (D) does not actually have a large influence on the data of the cut flat surface, there is a data that deviates from the actual situation. Concerns.

However, the "flat surface cut by the rectangle of the boundary line of the region (D)" is almost included in the "flat surface having a cumulative relative number of times of 30% or less from the case where the area of each flat surface is smaller."

Therefore, in the present invention, the standard deviation, the skewness, and the kurtosis of the flat surface in which the region (D) is present are not investigated, but the flat surface from which the region (D) exists is calculated as "the smaller the area from each flat surface is added. The standard deviation, skewness, and kurtosis of the "flat surface (S)" except for the flat surface with a cumulative relative number of 30% or less, which can be used by the region (D) The flat surface cut by the rectangle of the boundary line is adjusted to have a small influence on the values of the standard deviation, the skewness, and the kurtosis.

<Requirements (I-2)>

In the same state of the present invention, the adhesive sheet preferably has a plurality of flat faces in the region (D) of arbitrarily selected length 8 mm × width 10 mm on the surface (α), and removes the flat surface from the complex number. The smaller of the area, the relative number of times of the relative number of times is 30% or less of the flat surface, and the flatness (S) of each of the flat surfaces (S) is proportional to the area and frequency of the normal distribution curve Sk value of 1 the above.

In the present invention, the "skewness Sk value" defined by the requirement (I-2) indicates the degree of asymmetry of the normal distribution curve when the area and frequency of the statistically flat surface (S) are normally distributed.

If the skewness Sk value is 0, the distribution curve of the area and the frequency of the flat surface (S) becomes a bilaterally symmetrical shape.

If the skewness Sk value is >0 (the skewness Sk value is a positive value), the distribution curve of the area and frequency of the flat surface (S) has a shape in which the peak is shifted to the left and the tail end of the distribution curve extends to the right.

If the skewness Sk value is <0 (the skewness Sk value is a negative value), the distribution curve of the area and the frequency of the flat surface (S) is a shape in which the peak is shifted to the right and the tail end of the distribution curve is extended to the left.

Further, the larger the absolute value of the skewness Sk value, the larger the deformation.

In the requirement (I-2), the distribution of the area and frequency of the flat surface (S) in which the surface (α) exists is the frequency of the flat surface (S) which is smaller than the average value of the area of the flat surface (S). The higher the deformation, the wider the area of the flat surface (S) is specified.

It is considered that such a distribution is due to the fact that a flat surface (S) having a small area exists around the flat surface (S) of a large area. It is considered that the adhesion to the large flat surface is improved, and on the other hand, the deaeration property can be ensured by the concave portion adjacent to the small flat surface around the periphery.

In the same state of the present invention, as indicated by the skewness Sk value specified by the requirement (I-2), the periphery of the flat surface (S) having a large area due to the surface (α) of the adhesive layer is small. The unevenness of the flat surface (S) of the area causes a moderate deviation of the contact between the adhesive layer and the surface to be adhered, and the characteristics such as deaeration property, adhesive property, appearance, and press working can be improved in a balanced manner. Adhesive sheets.

In the same state of the present invention, as the requirement (I-2) The "skew Sk value" is preferably 1.0 or more, more preferably 1.1 or more, still more preferably 1.2 or more, and even more preferably 1.3 or more.

Further, there are a plurality of convex surfaces on the surface of the adhesive layer which is formed by using the unevenness of the embossed material having a specific shape and having a specific shape. The use of a plurality of flat surfaces (convex surfaces) formed by a release material having an embossed pattern existing on the surface of the adhesive layer is also various in size according to the design of the embossing pattern, but since the formation of the embossed pattern is complicated, Most of them are fixed in size, shape, etc., or a flat surface having a slightly identical shape is repeated, and the shape has a certain regularity.

When a plurality of flat surfaces formed by using a delaminating agent-type release agent are present on the surface of the adhesive layer, since the shape of the flat surface is regular, the skewness Sk value specified by the above requirement (I-2) is used. Less than 1.0.

In the present invention, the skewness Sk of each of the one or more flat faces (S) with respect to the normal distribution curve of the area and the frequency can be based on the following formula (2), using the chart software (Japan Microsoft Corporation, EXCEL) ) Calculated.

[In the formula (2), n represents the number of flat faces (S), x _i represents each area (i: 1, 2, ... n) of each flat face (S), and μ represents each flat face (S) The average of the area, s represents the standard deviation of the specimen].

<Requirements (I-3)>

In the same state of the present invention, the adhesive thin surface is preferably in a region (D) of an arbitrarily selected length of 8 mm × 10 mm on the surface (α), and a plurality of flat faces exist, and the flat surface existing from the plural is removed. The kurtosis Ku value of the normal distribution curve with respect to area and frequency of each of the flat surfaces (S) obtained by adding the relative number of the relative numbers of the relative number of times of less than 30% is 1.8. the above.

In the present invention, the "kurtosis Ku value" defined by the requirement (I-3) indicates the degree of difference between the peak of the statistically distributed peak and the distribution curve and the normal distribution curve.

If the kurtosis Ku value is =0, the shape of the distribution curve is substantially identical to the normal distribution curve.

If the kurtosis Ku value is >0 (the kurtosis Ku value is a positive value), the distribution curve has a sharper peak than the normal distribution curve, and the distribution curve has a thicker heavy end, that is, the width of the distribution curve end width is expanded. shape.

If the kurtosis Ku value is <0 (the kurtosis Ku value is a negative value), the distribution curve has a flatter peak than the normal distribution curve, and the distribution curve has a lighter tail end, that is, the display distribution curve has a smaller width at the end of the distribution curve. The shape.

The distribution of the area and frequency of the flat surface (S) in which the surface (α) exists in the element (I-3) is defined as a shape having a sharper peak than the normal distribution curve and a broadness of the end of the distribution curve.

The area Sk of the flat surface (S) has a skew value of 1.0 or more, and the kurtosis Ku value of 1.8 or more means the distribution of the area and frequency of the flat surface (S). The line has a shape that is biased toward a smaller number and deviates from the normal distribution.

That is, the distribution of the flat surface (S) existing on the surface (α) is a ratio that can sufficiently ensure the number of flat surfaces (S) having a small area, and the flat surface (S) having a large area is also minimized. The distribution that exists above the ratio. Therefore, it is possible to form an adhesive sheet in which the contact between the adhesive layer and the surface to be adhered is moderately adjusted, and various characteristics such as deaeration property, adhesive property, appearance, and press working can be improved.

In the same state of the present invention, the "kurtosis Ku value" defined as the requirement (I-3) is preferably 0.5 or more, more preferably 1.0 or more, still more preferably 1.5 or more, and even more preferably 1.8 or more. It is better than 1.9, and it is better to be 2.0 or more, and more preferably 2.1 or more.

Further, when a plurality of flat surfaces (convex surfaces) formed by using a release material having an embossed pattern having a specific shape by a general design are present on the surface of the adhesive layer, the flat surface shape is often regular. Therefore, the kurtosis Ku value specified by the above requirement (I-3) is less than 1.8.

In the present invention, the kurtosis Ku value of each of the one or more flat faces (S) with respect to the normal distribution curve of the area and the frequency may be based on the following formula (3), using the graphic software (Japan Microsoft Corporation, EXCEL) calculated.

[In the formula (3), n represents the number of flat faces (S), x _i represents each area (i: 1, 2, ... n) of each flat face (S), and μ represents each flat face (S) The average of the area, s represents the standard deviation of the specimen].

<Requirements related to the concave portion observed from the surface (α) side>

In the same state of the present invention, the concave portion which is amorphous when viewed from the surface (α) side in the presence of the surface (α) preferably exists in the surface (α), and preferably satisfies the following requirement (I-4).

. (I-4): In the region (D) of arbitrarily selected length 8 mm × width 10 mm on the surface (α), it is preferable to have 100% of the total area of the recess existing in the region (D). A recess of 70 to 99.99% (more preferably 85 to 99.99%).

By satisfying the requirement (I-4), it is possible to obtain an adhesive sheet in which various characteristics such as deaeration property and adhesive property are improved in a well-balanced manner.

Further, in the present invention, the total length of the concave portion existing in the region (D) in the region (D) of arbitrarily selected 8 mm × 10 mm wide on the surface (α) defined by the requirement (I-4) The area ratio of one recess of 100% of the area indicates the continuity of one recess. In the same aspect of the invention, in the region (D) arbitrarily selected from the surface (α) of the resin layer of the resin sheet, at least one of the recesses present in the region (D) is preferably opposite to the region. (D) The total area of the recessed portion in the memory is 100% continuous at a ratio of 70 to 99.99%, and the degassing property can be improved by the recess having such continuity.

In addition, the above-mentioned "area ratio of the area occupied by the concave portion" can be obtained by using a digital microscope (magnification: 30 to 100 times) to obtain a surface (α) For example, image processing (binarization processing) is performed on the image. Further, an image of the region is obtained by using a digital microscope (magnification: 30 to 100 times) in 1 to 10 regions of the region (D) having an arbitrarily selected length of 8 mm × 10 mm on the surface (α). The image calculates the value of the "area ratio of the area occupied by the concave portion or the flat surface" of each region, and regards the average of the values of the selected one to ten regions as the surface (α) of the resin layer existing on the adhesive sheet to be the target. "The proportion of the area occupied by the concave or flat surface".

In the same state of the present invention, the concave portion present on the surface (α) of the resin layer is preferably different from the transferer by the embossing pattern from the viewpoint of the continuity of the concave portion. By the design of the embossed pattern, it is also possible to have irregularities having one continuous recess. In the present invention, since the concave portion is not a transferr of the embossed pattern, there is no continuous one concave portion, in other words, preferably in the arbitrarily selected region (D) on the surface (α), with respect to the concave portion The total area of the recesses existing in the area (D) is 100%, and there is no one or more recesses having an area of 100%.

Further, in the present invention, the "area of the concave portion" can be obtained by using a digital microscope (magnification: 30 to 100 times) to obtain an image of the surface (α), and image processing (binarization processing) is performed on the image. Determined by automatic area measurement. The area ratio of the largest concave portion of the total area of the concave portion in the region (D) surrounded by the rectangular shape of 8 mm long by 10 mm in width which is arbitrarily selected on the surface (α) of the resin layer can be calculated based on the following formula.

Area ratio of the largest concave portion with respect to the total area of the concave portion = [maximum concave portion area] / [total total area of concave portion] × 100

In the same state of the invention, the surface of the resin layer (α) In the region (Q) surrounded by a square having a side of 1 mm, it is preferable to have one or more amorphous recesses, and it is preferable to have a plurality of amorphous recesses.

By having one or more amorphous recesses in the above region (Q), it is possible to obtain an adhesive sheet in which various characteristics such as deaeration property and adhesive property are improved in a well-balanced manner.

In the same state of the present invention, the concave portion 13 existing on the surface (α) 12a of the resin layer 12 preferably has a maximum height difference of 0.5 μm or more.

The term "recessed portion" as used herein means a depression having a maximum height difference of 0.5 μm or more, and it is not necessary to have a portion having a height difference of 0.5 μm or more in any portion of the concave portion, and it is not necessary to have a portion throughout the concave portion. Height difference of 0.5μm or more.

Fig. 3 is a schematic cross-sectional view showing the resin layer as an example of the shape of the surface (α) side of the resin layer of the adhesive sheet of the present invention.

As shown in FIG 3 (a) of the recessed portion 13 as shown, as the usually concave shape, having two mountain portions _{(M 1), (2 M} ) and valley portions (N). The "maximum height difference" of the concave portion in the present invention means the highest position (m) of the two mountain portions (M ₁ ) and (M ₂ ) in the thickness direction of the resin layer 12 (the mountain portion in Fig. 3(a) The length of the difference (h) between the (M ₁ ) maximum point and the lowest position (n) (the minimum point of the valley portion (N) in Fig. 3(a)).

Further, as shown in Fig. 3(b), it is considered that the concave portion 131 having two mountain portions (M ₁₁ ), (M ₁₂ ) and valley portion (N ₁ ) has two mountain portions (M ₁₂ ), ( M ₁₃ ) and _two recesses of the recess 132 of the valley portion (N ₂ ). In this case, the length of the difference between the maximum point of the mountain portion (M ₁₁ ) and the minimum point of the valley portion (N ₁ ) (h ₁ ) indicates the maximum height difference of the concave portion 131, and the maximum point and valley of the mountain portion (M ₁₃ ) The length of the difference (h ₂ ) between the minimum points of the portion (N ₂ ) indicates the maximum height difference of the concave portion 132.

The maximum height difference of the concave portion is preferably 1.0 μm or more and less than the thickness of the resin layer from the viewpoint of improving the degassing property of the adhesive sheet, the viewpoint of maintaining the appearance of the adhesive sheet, and the shape stability of the adhesive sheet. It is more preferably 3.0 μm or more and less than the thickness of the resin layer, more preferably 5.0 μm or more and less than the thickness of the resin layer.

Moreover, the average value of the width of the concave portion is preferably from 1 to 500 μm, more preferably from 3 to 400 μm, and even more preferably 5 from the viewpoint of improving the deaeration property of the adhesive sheet and the adhesion of the adhesive sheet. ~300μm.

Further, in the present invention, the width of the concave portion means the distance between the maximum points of the two mountain portions, and in the concave portion 13 shown in Fig. 3(a), the mountain portion (M ₁ ) and the mountain portion (M) ₂ ) The distance L. Further, in the recess 131 shown in FIG. 3(b), the distance L ₁ between the mountain portion (M ₁₁ ) and the mountain portion (M ₁₂ ) is referred to, and in the concave portion 132, the mountain portion (M ₁₃ ) and the mountain portion are referred to. The distance (M ₁₂ ) is L ₂ .

Further, when the adhesive sheet of the present invention is viewed in plan (when viewed from directly above), when the concave portion has a long side and a short side, the short side is defined as a width.

As for the ratio of the maximum height difference of the one concave portion to the average value of the width [the average value of the maximum height difference/width] (the concave surface shown in Fig. 3(a)) In the part 13, the term "h/L" is preferably 1/500 to 100/1, more preferably 3/400, from the viewpoint of improving the deaeration property of the adhesive sheet and the adhesion of the adhesive sheet. ~70/3, and better still 1/60~10/1.

In the same state of the present invention, based on the viewpoint of the presence of a plurality of concave portions and an adhesive sheet satisfying the flat surfaces of the above-mentioned requirements (Ii) and (Iii), it is preferable to further adhere to the concave portion satisfying the requirement (I-4). From the viewpoint of the sheet, it is preferable that the concave portion is formed by using a release material having an embossing pattern.

The "concave portion formed by using a release material having an emboss pattern" is exemplified by, for example, the following, which is different from the concave portion of the above-described form.

. On the flat surface of the adhesive layer formed from the adhesive composition, the embossed pattern of the release sheet is pressed, and the concave portion formed by the transfer of the embossed pattern is pressed.

. The release sheet used for the embossing pattern is applied to the release-treated surface, and the adhesive composition is applied to the release-treated surface to form a pressure-sensitive adhesive layer, and then the concave portion exposed on the surface of the adhesive layer is removed.

These recesses cause problems associated with the adhesive sheets described in the above-mentioned Patent Document 1, and are listed as several defects.

In the same manner as in the present invention, the concave portion is preferably formed by the formation of the resin layer itself, from the viewpoint of forming the adhesive sheet satisfying the concave portion and the flat surface of the above-mentioned requirements on the surface (α) of the resin layer.

In the present invention, the term "self-formation" means a phenomenon in which a natural disordered shape is formed in the process of self-discipline formation of a resin layer, and more specifically, It means that the coating film formed from the composition of the material forming the resin layer is dried, and a natural disordered shape is formed in the process of self-discipline formation of the resin layer.

Further, the shape of the concave portion formed by the formation of the resin layer itself can be adjusted to some extent by adjusting the type or content of the component in the composition of the drying material or the material for forming the resin layer, but by pressing The grooves formed by the transfer of the pattern are different, and it can be said that "the fact that the identical shape cannot be reproduced". Therefore, the concave portion formed by the formation of the resin layer itself can be said to be amorphous.

Further, by forming the concave portion of the amorphous shape, the shape of the flat surface is also amorphous.

The formation process of the concave portion formed by the formation of the resin layer itself is considered as follows.

First, in the formation of a coating film formed of a composition which is a material for forming a resin layer, in the step of drying the coating film, shrinkage stress is generated inside the coating film, and the bonding strength of the resin is weakened. Cracks are formed in the coating film. Therefore, it is considered that the resin in the periphery of the cracked portion flows into the space temporarily generated by the crack, and a concave portion is formed on the surface (α) of the resin layer.

It is considered that after the two coating films having different resin contents are formed, the two coating films are simultaneously dried, and a shrinkage stress difference occurs inside the coating film during drying, and coating film cracking easily occurs.

Moreover, it is preferable to appropriately adjust the following matters from the viewpoint of easily forming a concave portion. It is considered that the formation of the concave portion is facilitated by the composite action due to such matters. Incidentally, in order to easily form a concave portion The preferred form of each item is as described in the item to be described later.

. The type, constituent monomer, molecular weight, and content of the resin contained in the composition of the coating film forming material.

. The type of the crosslinking agent and the type of the solvent contained in the composition of the coating film forming material.

. The viscosity of the composition of the coating film forming material and the solid content concentration.

. Film thickness formed (in the case of multiple layers, the thickness of each coating film)

. The drying temperature and drying time of the formed coating film.

Further, in the formation of the adhesive layer of the adhesive sheet in general, for the purpose of forming an adhesive layer having a flat surface, the above-described matters are often set as appropriate.

On the other hand, the present invention sets the above matters in such a manner as to form a concave portion which contributes to the improvement of the deaeration property of the adhesive sheet, and is completely different from the design method of the adhesive layer of the general adhesive sheet.

The above matters are preferably set as appropriate in consideration of the fluidity and the like of the resin contained in the formed coating film.

For example, when the fine particles are contained in the composition, the specific fluidity of the fine particles in the coating film can be maintained by adjusting the viscosity of the coating film formed of the composition containing a large amount of fine particles, and the coating film can be moderately suppressed (otherwise). Intermixing of coatings containing more resin). By such adjustment, in the coating film containing a large amount of resin, cracks are generated in the horizontal direction, and the concave portion tends to be formed.

As a result, the proportion of the concave portion formed on the surface (α) can be increased, and the ratio of the concave portions connected to each other can be increased, and the adhesive sheet having more excellent deaeration property can be obtained.

Moreover, in the above-mentioned matter, it is preferred to appropriately adjust the type, constituent monomer, molecular weight, and resin content of the resin so that the resin contained in the coating film containing a large amount of resin has moderate viscoelasticity.

That is, by making the hardness of the coating film (hardness determined by factors such as the viscoelasticity of the resin and the viscosity of the coating liquid) moderately hard, the shrinkage stress of the resin portion (X) can be enhanced, and the concave portion can be easily formed. The harder the hardness of the coating film is, the stronger the shrinkage stress is, and the concave portion tends to occur, but the coating suitability is lowered when it is too hard. Further, when the resin elasticity is excessively increased, the adhesive strength of the resin layer formed of the coating film tends to decrease. When considering this aspect, it is preferable to appropriately adjust the viscoelasticity of the resin.

When the fine particles are contained in the composition or the coating film, it is considered that the degree of swelling of the resin layer due to the fine particles can be easily adjusted, or the self-forming force of the concave portion can be easily adjusted, and the surface is easily formed. A person who forms a recess on (α).

Further, it is preferable to appropriately set the above-mentioned matters by considering the crosslinking speed of the formed coating film (or the composition of the forming material).

That is, when the crosslinking speed of the coating film is too fast, the coating film may be hardened before the concave portion is formed. Moreover, it also affects the crack size and the size of the concave portion of the coating film.

The crosslinking speed of the coating film can be adjusted by appropriately setting the type of the crosslinking agent and the type of the solvent in the composition forming the material, or the drying time and drying temperature of the coating film.

Further, when the resin layer is a layer containing a resin-containing resin portion (X) and a particle portion (Y) formed of fine particles, the resin layer formed by the above-described self-forming is as shown in Fig. 1 (a) to d) shown, particles The portion (Y) tends to have a concave portion on the surface (α), and the proportion of the particle portion (Y) tends to be smaller than that of the other portions.

In the process of forming the resin layer itself, when the concave portion is formed on the surface (α) of the resin layer, the fine particles existing at the position where the concave portion is formed are moved to become such a distributor.

The respective configurations of the adhesive sheet of the present invention will be described below.

[substrate]

The substrate to be used in the same state of the present invention is not particularly limited, and examples thereof include a paper substrate, a resin film or a sheet, a substrate obtained by laminating a paper substrate with a resin, and the like, which can be adhered according to the present invention. The use of the sheet is appropriately selected.

Examples of the paper constituting the paper substrate are, for example, a sheet paper, a medium paper, a top paper, an impregnated paper, a coated paper, a coated paper, a sulfuric acid paper, a cellophane or the like.

Examples of the resin constituting the resin film or sheet are polyolefin resins such as polyethylene and polypropylene; polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, and the like. Vinyl resin; polyester resin such as polyethylene terephthalate, polybutylene terephthalate or polyethylene naphthalate; polystyrene; acrylonitrile-butadiene-styrene Copolymer; cellulose triacetate; polycarbonate; urethane resin such as polyurethane, acrylic modified polyurethane; polymethylpentene; polyfluorene; polyether ether ketone Polyether oxime; polyphenylene sulfide; polyethylenimine-based resin such as polyether sulfimine or polyimine; polyamine-based resin; acrylic resin; fluorine-based resin.

The base material obtained by laminating the paper base material with a resin is exemplified by laminating the paper base material with a thermoplastic resin such as polyethylene.

Preferably, the substrate is a resin film or sheet, more preferably a film or sheet made of a polyester resin, and more preferably a film or sheet made of polyethylene terephthalate (PET). .

Further, when the adhesive sheet of the present invention is used for applications requiring heat resistance, it is preferably a film or sheet composed of a resin selected from the group consisting of polyethylene naphthalate and a polyimide resin, and is used for weather resistance. In the case of use, it is preferably a film or sheet composed of a resin selected from the group consisting of polyvinyl chloride, polyvinylidene chloride, acrylic resin, and fluororesin.

The thickness of the substrate is appropriately set according to the use of the adhesive sheet of the present invention, but it is preferably from 5 to 1,000 μm, more preferably from 10 to 500 μm, even more preferably from 12 to 250 μm, from the viewpoint of handleability and economy. Good 15~150μm.

Further, the substrate may further contain various additives such as an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an anti-blocking agent, and a colorant.

Further, the substrate used in the same state of the present invention is preferably a non-air permeable substrate from the viewpoint of improving the burst resistance of the obtained adhesive sheet, and specifically, preferably has a surface on the surface of the above resin film or sheet. The substrate of the metal layer.

The metal contained in the metal layer is exemplified by a metal having a metallic luster such as aluminum, tin, chromium or titanium.

As a method of forming the metal layer, for example, by vacuum evaporation, A method of depositing the above metal by a PVD method such as sputtering or ion plating, or a method of attaching a metal foil made of the above metal using a general adhesive, is preferably a method of depositing the metal by a PVD method.

Further, when a resin film or a sheet is used as the substrate, the surface of the resin film or the sheet may be subjected to oxidation by the viewpoint of improving the adhesion to the resin layer laminated on the resin film or sheet. Surface treatment or primer treatment such as embossing.

Examples of the oxidation method include, for example, a corona discharge treatment, a plasma discharge treatment, a chromic acid treatment (wet type), a hot air treatment, an ozone treatment, and an ultraviolet irradiation treatment. Examples of the unevenness method include a sandblasting method and a solvent treatment method.

[release material]

The release material which is in the same state as the present invention is exemplified by a release sheet which has been subjected to release treatment on both sides, a release sheet which has been subjected to release treatment on one side, and the release agent is applied to a substrate for a release material.

Further, the release-treated surface is preferably a flat release material (for example, a release material having no emboss pattern).

The base material for the release material is, for example, the above-mentioned paper base material, resin film or sheet used as a base material of the adhesive sheet of the present invention, and a base material obtained by laminating a paper base material with a resin. .

Examples of the release agent include a rubber-based elastomer such as a polyfluorene-based resin, an olefin-based resin, an isoprene-based resin, and a butadiene-based resin, a long-chain alkyl-based resin, an alkyd-based resin, and a fluorine-based resin. Wait.

The thickness of the release material is not particularly limited, and is preferably 10 to 200 μm. It is preferably 25 to 170 μm, and more preferably 35 to 80 μm.

[resin layer]

As shown in Fig. 1, the resin layer 12 of the adhesive sheet of the present invention preferably comprises a resin-containing resin portion (X) and a particle portion (Y) formed of fine particles.

The resin portion (X) indicates a portion containing components other than the fine particles contained in the resin layer. In other words, the resin layer contains not only the resin but also components other than the fine particles such as the adhesion-imparting agent, the crosslinking agent, and the general-purpose additive, in the "resin portion (X)".

On the other hand, the particle portion (Y) represents a portion formed by the fine particles contained in the resin layer.

By the particle-containing portion (Y) in the resin layer, the shape retainability after the attachment can be improved, and when the obtained adhesive sheet is used at a high temperature, the occurrence of burst can be effectively suppressed.

The composition of the distribution of the resin portion (X) and the particle portion (Y) in the resin layer 12 may be a composition in which the resin portion (X) and the particle portion (Y) are substantially uniformly distributed, and may be further divided into a portion mainly by a resin portion. The portion formed by (X) and the portion mainly composed of the particle portion (Y).

The adhesive layer of the adhesive sheet of the same state of the present invention preferably has a void portion (Z) in addition to the resin portion (X) and the particle portion (Y). The burst resistance of the adhesive sheet can be improved by having the void portion (Z) in the resin layer.

The void portion (Z) also includes the presence of the aforementioned microparticles between each other The void or the void existing in the secondary particle when the particle is a secondary particle.

Further, when the resin layer has a multilayer structure, even if a void portion (Z) is present during or after the formation of the resin layer, the resin portion (X) flows into the void portion (Z) to cause the void to disappear and become a void-free portion. The case of the resin layer of (Z).

However, even in the case where the void portion (Z) existing in the resin layer for a short period of time disappears, the adhesive sheet of the same state of the present invention has a recessed portion due to the surface (α) of the resin layer, so that the degassing property is good, and Since the layer has a particle portion (Y), it is also excellent in burst resistance.

Further, the shear storage elastic modulus at 100 ° C of the resin layer of the adhesive sheet of the same state of the present invention is preferably 9.0 × 10 ³ Pa from the viewpoint of improving the deaeration property and burst resistance of the adhesive sheet. The above is more preferably 1.0 × 10 ⁴ Pa or more, and still more preferably 2.0 × 10 ⁴ Pa or more.

Further, the shear storage elastic modulus at 100 ° C of the resin layer in the present invention means that the measured value is measured at a frequency of 1 Hz using a viscoelasticity measuring apparatus (for example, a device name "DYNAMIC ANALYZER RDA II" manufactured by Rheometrics Co., Ltd.). .

The total thickness of the resin layer is preferably from 1 to 300 μm, more preferably from 5 to 150 μm, still more preferably from 10 to 75 μm.

The adhesive sheet of the present invention has adhesiveness at least on the surface (α) of the resin layer which is the opposite side to the side on which the substrate or the release material is provided, but the surface of the resin layer on the side where the substrate or the release material is provided (β) can also have adhesiveness.

The adhesion of the surface (α) of the resin layer of the adhesive sheet of the same state of the present invention is preferably 0.5 N/25 mm or more, more preferably 2.0 N/25 mm or more, and still more preferably 3.0 N/25 mm or more. It is 4.0N/25mm or more, and more preferably 7.0N/25mm or more.

When the surface (β) of the resin layer also has adhesiveness, the adhesion of the surface (β) preferably falls within the above range.

Further, the value of the adhesive force of the adhesive sheet means the value measured by the method described in the examples.

<Multilayer Structure of Resin Layer>

The resin layer may be a multilayer structure composed of two or more layers.

The resin layer as such a multilayer structure is exemplified by the adhesive sheet 1a of Fig. 1, etc., from the side on which the substrate or the release material is provided, in accordance with the layer (Xβ) mainly containing the resin portion (X), and the particle-containing portion. (Y) A multilayer structure in which a layer (Y1) of 15% by mass or more and a layer (Xα) mainly comprising a resin portion (X) are laminated in this order.

Further, in the configuration of the multilayer structure of the resin layer, the mixed layer state in which the boundary of the two layers of the laminate cannot be determined can be used.

In other words, in the resin layer 12 of the adhesive sheet 1a of FIG. 1, the boundary between the layer (Xβ) and the layer (Y1) and/or the boundary between the layer (Y1) and the layer (Xα) cannot be discriminated. Composition.

Hereinafter, the resin layer 12 composed of three layers of a layer (Xβ), a layer (Y1), and a layer (Xα) of the adhesive sheet 1a of Fig. 1 is used. As an example, the configuration of the resin layer of the multilayer structure will be described.

The layer (Xβ) and the layer (Xα) mainly contain a layer of the resin portion (X), but may also contain a particle portion (Y). However, the content of the particle portion (Y) in the layer (Xβ) and the layer (Xα) is independently less than 15% by mass, and less than the total mass (100% by mass) of the layer (Xβ) or the layer (Xα). The resin content in the layer (Xβ) or layer (Xα).

That is, the layer (Xβ) and the layer (Xα) are different from the layer (Y1) from the viewpoint of the content of the particle portion (Y).

Further, the layer (Xβ) and the layer (Xα) may further have the above-described void portion (Z) in addition to the resin portion (X) and the particle portion (Y).

The content of the resin portion (X) in the layer (Xβ) and the layer (Xα) is usually more than 85% by mass, preferably 87, based on the total mass (100% by mass) of the layer (Xβ) or the layer (Xα), respectively. ~100% by mass, more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass, and even more preferably 100% by mass.

In addition, the "content of the resin portion (X)" means a fine particle such as a resin, an adhesion-imparting agent, a crosslinking agent, and a general-purpose additive which constitute the resin portion (X) contained in the layer (Xβ) or the layer (Xα). The total content of the ingredients other than the ingredients.

The content of the fine particles of the particle portion (Y) in the constituent layer (Xβ) and the layer (Xα) is independently less than 15% by mass, preferably less than 15% by mass, based on the total mass (100% by mass) of the layer (Xβ) or the layer (Xα). It is 0 to 13% by mass, more preferably 0 to 10% by mass, still more preferably 0 to 5% by mass, and even more preferably 0% by mass.

Further, in the present invention, the "fine particle content in the layer (X?) and the layer (X?)" can also be regarded as the total amount of the resin composition of the layer (X?) and the layer (X?) forming material (100% by mass (but The amount of fine particles in the diluent)).

The content of the resin in the layer (Xα) is usually 30 to 100% by mass, preferably 40 to 100% by mass, more preferably 50 to 100% by mass, based on the total mass (100% by mass) of the layer (Xα). It is preferably 60 to 100% by mass.

On the other hand, the content of the resin in the layer (Xβ) is usually 50 to 100% by mass, preferably 65 to 100% by mass, more preferably 75 to 5% by mass based on the total mass (100% by mass) of the layer (Xβ). 100% by mass, and more preferably 85 to 100% by mass.

Further, in the present invention, the "resin content in the layer (Xβ) and the layer (Xα)" may be regarded as the total amount of the resin composition of the layer (Xβ) or the layer (Xα) forming material (100% by mass (but Resin content except for the dilution solvent)).

The layer (Y1) may be a layer formed only of the particle portion (Y), or a layer containing the resin portion (X) together with the particle portion (Y), and further may be a layer having a void portion (Z). .

The content of the fine particles in the particle portion (Y) in the constituent layer (Y1) is 15% by mass or more, preferably 20% to 100% by mass, more preferably 25 to 90% by mass based on the total mass (100% by mass) of the layer (Y1). %, more preferably 30 to 85% by mass, and even more preferably 35 to 80% by mass.

The resin content in the constituent layer (Y1) is relative to the layer (Y1) The total mass (100% by mass) is usually 0 to 85% by mass, preferably 1 to 80% by mass, more preferably 5 to 75% by mass, still more preferably 10 to 70% by mass, and even more preferably 20 to 20% by mass. 65% by mass.

In the present invention, the "fine particle content in the layer (Y1)" and the "resin content in the layer (Y1)" can also be regarded as the total amount of the constituent material of the layer (Y1) (100% by mass (but The content of fine particles or resin in the diluent)).

In the same state of the present invention, the layer (Xα) is preferably a layer formed of a composition (xα) containing a resin and having a fine particle content of less than 15% by mass.

Similarly, the layer (X?) is also preferably a layer formed of a composition (x?) containing a resin and having a fine particle content of less than 15% by mass.

Further, the layer (Y1) is preferably a layer formed of a composition (y) containing fine particles of 15% by mass or more.

Further, preferred embodiments (including components, contents, and the like) of the composition (xα), the composition (xβ), and the composition (y1) will be described later.

<Resin part (X)>

The resin portion (X) constituting the resin layer contains a portion other than the fine particles contained in the resin layer, and is different from the particle portion (Y) in this respect.

The resin portion (X) may contain an adhesion-imparting agent, a crosslinking agent, a general-purpose additive, and the like together with the resin.

The resin content in the resin portion (X) relative to the resin portion The total amount (100% by mass) of (X) is usually 30% by mass or more, preferably 40% by mass or more, more preferably 50% by mass or more, still more preferably 55% by mass or more, and still more preferably 60% by mass. The above is more preferably 70% by mass or more, and is preferably 100% by mass or less, more preferably 99.9% by mass or less.

Further, in the present invention, the value of the resin content in the resin composition forming the material of the resin portion (X) can also be regarded as the "resin content in the resin portion (X)".

The resin contained in the resin portion (X) is preferably an adhesive resin based on the viewpoint of exhibiting adhesion to the surface (α) of the formed resin layer.

In particular, as in the adhesive sheet 1a of Fig. 1(a), the resin layer is formed by laminating the layers (Xβ), the layers (Y1) and the layers (Xα) from the side on which the substrate or the release material is provided. In the multilayer structure, it is preferred that at least the layer (Xα) contains an adhesive resin based on the above viewpoint.

Further, from the viewpoint of the constitution of the double-sided adhesive sheet and the improvement of the adhesion to the substrate, it is preferred that at least the layer (Xα) and the layer (Xβ) contain an adhesive resin.

Examples of the adhesive resin include an acrylic resin, a urethane resin, a rubber resin, and a polyoxyn resin.

Among these adhesive resins, an acrylic resin is preferably contained because it is excellent in adhesion properties and weather resistance, and is easy to form a concave portion on the surface (α) of the resin layer.

The content of the acrylic resin is relative to the resin portion (X) The total amount of the resin (100% by mass) is preferably from 25 to 100% by mass, more preferably from 50 to 100% by mass, still more preferably from 70 to 100% by mass, even more preferably from 80 to 100% by mass, and furthermore More preferably 100% by mass.

Moreover, the resin portion (X) preferably contains a resin having a functional group, and more preferably an acrylic resin having a functional group, from the viewpoint of facilitating the formation of the concave portion on the surface (α) of the resin layer.

In particular, as in the adhesive sheet 1a of Fig. 1(a), the resin layer is formed by laminating the layers (Xβ), the layers (Y1) and the layers (Xα) from the side on which the substrate or the release material is provided. In the case of the multilayer structure, it is preferred that at least the layer (Y1) contains a resin having a functional group based on the above viewpoint.

The functional group is a group which is a starting point for crosslinking with a crosslinking agent, and examples thereof include a hydroxyl group, a carboxyl group, an epoxy group, an amine group, a cyano group, a ketone group, an alkoxyalkyl group, and the like, and are preferably a carboxyl group.

The resin portion (X) preferably contains a resin having the aforementioned functional group and further contains a crosslinking agent. In particular, when the resin layer is the multilayer structure, at least the layer (Y1) preferably contains a resin having the above functional group and further contains a crosslinking agent.

Examples of the crosslinking agent include, for example, an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, and a metal chelate crosslinking agent.

Examples of the isocyanate crosslinking agent include aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, and xylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; isophorone diisocyanate and hydrogenation. An alicyclic polyisocyanate such as diphenylmethane diisocyanate; and a carbamide, isocyanuric acid of such compounds An ester body and an adduct of a reactant with a low molecular weight active hydrogen-containing compound (ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc.);

Examples of the epoxy-based crosslinking agent are, for example, ethylene glycol diglycidyl ether, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'. - tetraglycidyl-m-xylylenediamine, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidylaniline, diglycidylamine, and the like.

Examples of the aziridine-based crosslinking agent are, for example, diphenylmethane-4,4'-bis(1-aziridine carboxamide), trimethylolpropane tris-β-aziridine propionate, and four. Methyl hydroxymethyl methane tri-β-aziridine propionate, toluene-2,4-bis(1-aziridine carboxamide), tri-ethyl melamine, bis-m-xylylene-1- 2-methylaziridine), tri-1-(2-methylaziridine)phosphine, trimethylolpropane tri-β-(2-methylaziridine) propionate, and the like.

The metal chelate-based crosslinking agent is exemplified by a chelate compound in which the metal atom is aluminum, zirconium, titanium, zinc, iron, tin, or the like, but is preferably aluminum based on the viewpoint that the surface (α) of the resin layer is easily formed into a concave portion. Chelate-based crosslinker.

Examples of the aluminum chelate crosslinking agent are, for example, aluminum diisopropoxide, monooleylacetate, monoisopropoxy aluminum bisacetoacetate, and monoisopropoxy aluminum. Ethyl monoethylacetate acetate, aluminum dilaurate, monolaurylacetate, diisopropoxy aluminum monostearyl acetate, diisopropoxide aluminum Stearyl ethyl acetate and the like.

Further, these crosslinking agents may be used alone or in combination of two or more. use.

In the above, the resin portion (X) preferably contains at least one selected from the group consisting of a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent, from the viewpoint of facilitating the formation of the concave portion on the surface (α) of the resin layer. It is preferable to contain a metal chelate crosslinking agent and, more preferably, an aluminum chelate crosslinking agent.

The content of the crosslinking agent in the resin portion (X) is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the resin having a functional group contained in the resin portion (X). More preferably 0.3 to 7.0 parts by mass.

Further, in the same manner as in the present invention, the resin portion (X) preferably contains a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent from the viewpoint of facilitating the formation of the concave portion on the surface (α) of the resin layer.

When the resin portion (X) contains a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent, the metal chelate-based crosslinking agent and the epoxy-based crosslinking agent in the resin portion (X) are based on the above viewpoint. The content ratio of the [metal chelate crosslinking agent/epoxy crosslinking agent] is preferably 10/90 to 99.5/0.5, more preferably 50/50 to 99.0/1.0, and more preferably. It is 65/35~98.5/1.5, and even better is 75/25~98.0/2.0.

The resin portion (X) preferably contains an adhesive resin and further contains an adhesion-imparting agent from the viewpoint of further improving the adhesion characteristics of the surface (α). In particular, when the resin layer is the multilayer structure, the layer (Xα) preferably contains an adhesive resin and an adhesion-imparting agent.

Further, the adhesion-imparting agent used in the present invention means a component which assists in improving the adhesion of the adhesive resin, and has a mass average molecular weight (Mw). An oligomer of less than 10,000 is often distinguished from the above adhesive resin.

The mass average molecular weight (Mw) of the adhesion-imparting agent is preferably from 400 to 8,000, more preferably from 5,000 to 5,000, still more preferably from 800 to 3,500.

Examples of the adhesion-imparting agent include rosin-based resins such as rosin resin, rosin ester resin, and rosin-modified phenol resin; hydrogenated rosin-based resins obtained by hydrogenation of these rosin-based resins; terpene resins and aromatic modified terpene resins; a terpene-based resin such as a terpene phenol-based resin; a hydrogenated terpene-based resin obtained by hydrogenating the terpene-based resin; a styrene-based monomer such as α-methylstyrene or β-methylstyrene, and an aliphatic group a styrene-based resin obtained by copolymerization of monomers; a hydrogenated styrene-based resin obtained by hydrogenating the styrene-based resin; pentene, isoprene, piperine, 1, which is formed by thermal decomposition of petroleum brain; a C5-based petroleum resin obtained by copolymerizing a C5 fraction such as 3-pentadiene and a hydrogenated petroleum resin of the C5-based petroleum resin; a C9 fraction obtained by thermal decomposition of petroleum brain, and a C9 fraction such as vinyl toluene A C9-based petroleum resin and a hydrogenated petroleum resin of the C9-based petroleum resin;

The adhesion-imparting agent used in the present invention may be used singly or in combination of two or more kinds of softening points or different structures.

The softening point of the adhesion-imparting agent is preferably 80 ° C or more, more preferably 80 to 180 ° C, still more preferably 83 to 170 ° C, and even more preferably 85 to 150 ° C.

In the present invention, the "softening point" of the adhesion-imparting agent means a value measured in accordance with JIS K 2531.

When two or more kinds of the plurality of adhesion-imparting agents are used, the weighted average of the softening points of the plurality of the adhesion-imparting agents preferably falls within the above range.

When the resin part (X) contains an adhesion-imparting agent, it is adhesive. The content of the precipitant is preferably 1 part by mass or more, more preferably 1 to 200 parts by mass, even more preferably 3 to 150 parts by mass, based on 100 parts by mass of the adhesive resin contained in the resin portion (X). More preferably 5 to 90 parts by mass.

Further, the resin portion (X) may contain a general-purpose additive other than the above-mentioned crosslinking agent or adhesion-imparting agent.

Typical additives are, for example, antioxidants, softeners (plasticizers), rust inhibitors, pigments, dyes, retarders, reaction accelerators, ultraviolet absorbers, and the like.

Further, these general-purpose additives may be used alone or in combination of two or more.

When the general-purpose additive is contained, the content of each general-purpose additive is preferably 0.0001 to 60 parts by mass, more preferably 0.001 to 50 parts by mass, per 100 parts by mass of the resin.

The resin contained in the resin portion (X) may be used alone or in combination of two or more.

The material for forming the resin portion (X) of the resin layer of the adhesive sheet of the present invention is preferably an adhesive containing an adhesive resin having a functional group, more preferably an acrylic resin (A) having a functional group ( Hereinafter, the acrylic adhesive is also referred to as "acrylic resin (A)"), and is preferably an acrylic adhesive containing an acrylic resin (A) having a functional group and a crosslinking agent (B).

The acrylic adhesive may be either a solvent type or an emulsion type.

The above-mentioned acrylic adhesive as a material for forming the resin portion (X) will be described below.

The acrylic resin (A) contained in the acrylic pressure-sensitive adhesive is exemplified by, for example, a polymer having a constituent unit derived from an alkyl (meth)acrylate having a linear or branched alkyl group, derived from a ring. A polymer or the like which is a constituent unit of a (meth) acrylate having a structure.

The mass average molecular weight (Mw) of the acrylic resin (A) is preferably from 50,000 to 1.5 million, more preferably from 150,000 to 1.3 million, more preferably from 250,000 to 1.1 million, and even more preferably from 350,000 to 90. Million.

The acrylic resin (A) preferably contains a composition of an alkyl (meth)acrylate (a1') derived from an alkyl group having 1 to 18 carbon atoms (hereinafter also referred to as "monomer (a1')"). The unit (a1) and the acrylic copolymer (A1) derived from the constituent unit (a2) of the functional group-containing monomer (a2') (hereinafter also referred to as "monomer (a2')") are more preferably acrylic. Copolymer (A1).

The content of the acrylic copolymer (A1) is preferably from 50 to 100% by mass, more preferably from 70 to 100% by mass, based on the total amount (100% by mass) of the acrylic resin (A) in the acrylic pressure-sensitive adhesive. It is preferably 80 to 100% by mass, and more preferably 90 to 100% by mass.

Further, the copolymerization form of the acrylic copolymer (A1) is not particularly limited, and may be any of a block copolymer, a random copolymer, and a graft copolymer.

The carbon number of the alkyl group which the monomer (a1') has is preferably from 4 to 12, more preferably from 4 to 8, more preferably from 4 to 6, from the viewpoint of improving the adhesion property.

As the monomer (a1'), for example, (meth)acrylic acid Ester, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, (methyl) Tridecyl acrylate, stearyl (meth) acrylate, and the like.

Among these, butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate are preferred, and butyl (meth)acrylate is more preferred.

The content of the constituent unit (a1) is preferably from 50 to 99.5% by mass, more preferably from 60 to 99% by mass, even more preferably 70% based on the total constituent unit (100% by mass) of the acrylic copolymer (A1). ~95% by mass, and more preferably 80 to 93% by mass.

As the monomer (a2'), for example, a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an epoxy group-containing monomer, an amine group-containing monomer, a cyano group-containing monomer, a ketone group-containing monomer, and an alkoxy group-containing group are exemplified. A decyl monomer or the like.

Among these, it is more preferably a carboxyl group-containing monomer.

The carboxyl group-containing monomer is exemplified by (meth)acrylic acid, maleic acid, fumaric acid, oriconic acid, etc., preferably (meth)acrylic acid.

The content of the constituent unit (a2) is preferably from 0.5 to 50% by mass, more preferably from 1 to 40% by mass, even more preferably 5 to the total constituent unit (100% by mass) of the acrylic copolymer (A1). ~30% by mass, and more preferably 7-20% by mass.

Further, the acrylic copolymer (A1) may contain a constituent unit (a3) derived from the monomer (a3') other than the above monomers (a1') and (a2').

As the other monomer (a3'), for example, a (meth)acrylic acid ring is exemplified. Hexyl ester, benzyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dipentyl (meth)acrylate, dicyclopentyl (meth)acrylate A (meth) acrylate, vinyl acetate, acrylonitrile, styrene or the like having a cyclic structure such as a ethyl ester or a quinone imine (meth) acrylate.

The content of the constituent unit (a3) is preferably from 0 to 30% by mass, more preferably from 0 to 20% by mass, even more preferably 0 to the total constituent unit (100% by mass) of the acrylic copolymer (A1). ~10% by mass, and more preferably 0 to 5% by mass.

Further, the above-mentioned monomers (a1') to (a3') may be used alone or in combination of two or more.

The method for synthesizing the component of the acrylic copolymer (A1) is not particularly limited, and for example, a method of solution polymerization in the presence of a polymerization initiator, a chain transfer agent or the like by dissolving a raw material monomer in a solvent, or In the presence of an emulsifier, a polymerization initiator, a chain transfer agent, a dispersant or the like, the raw material monomers are produced by aqueous emulsion polymerization.

The crosslinking agent (B) contained in the acrylic pressure-sensitive adhesive is exemplified as the above-mentioned one. However, it is preferable to contain a metal chelate based on the viewpoint that the adhesive property is improved and the concave portion is easily formed on the surface (α) of the resin layer. One or more kinds of the crosslinking agent and the epoxy crosslinking agent are contained, and the metal chelate crosslinking agent is more preferably contained, and the aluminum chelate crosslinking agent is more preferably contained.

In addition, as a crosslinking agent (B), it is preferable to contain a metal chelate-based crosslinking agent and a ring together as a crosslinking agent (B) from the viewpoint of improving the shape retention of the plurality of concave portions present on the surface (α) of the resin layer. Oxygen cross-linking Agent.

The content of the crosslinking agent (B) is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, even more preferably 100 parts by mass based on 100 parts by mass of the acrylic resin (A) in the acrylic pressure-sensitive adhesive. 0.3 to 7.0 parts by mass.

When a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent are used together, the content of the metal chelate-based crosslinking agent and the epoxy-based crosslinking agent is higher than that of the "metal chelate-based crosslinking agent/epoxy system". The crosslinking agent is preferably 10/90 to 99.5/0.5, more preferably 50/50 to 99.0/1.0, still more preferably 65/35 to 98.5/1.5, and even more preferably 75/25. ~98.0/2.0.

The acrylic pressure-sensitive adhesive used in the same state of the present invention may contain a general-purpose additive within a range not impairing the effects of the present invention. The above-mentioned one is exemplified as a general-purpose additive, and the content of the general-purpose additive is also as described above.

Further, the acrylic pressure-sensitive adhesive used in the same state of the present invention preferably further contains an adhesion-imparting agent from the viewpoint of further improving the adhesion characteristics of the surface (α). Examples of the adhesion-imparting agent are those described above, and the content of the adhesion-imparting agent is also as described above.

The acrylic pressure-sensitive adhesive used in the same manner as the present invention may contain an adhesive resin other than the acrylic resin (A) (for example, an urethane-based resin or a rubber system, within the range not impairing the effects of the present invention). Resin, polysiloxane resin, etc.).

The content of the acrylic resin (A) in the acrylic adhesive relative to the total amount of the adhesive resin contained in the acrylic adhesive (100 mass) %), preferably 50 to 100% by mass, more preferably 70 to 100% by mass, still more preferably 80 to 100% by mass, and even more preferably 100% by mass.

<particle part (Y)>

In the resin layer which the adhesive sheet of the same state of the present invention has, it is preferable to contain the particle portion (Y) formed by the fine particles.

The average particle diameter of the fine particles is preferably from 0.01 to 100 μm, more preferably from 0.05 to 0, from the viewpoint of improving the degassing property and the burst resistance of the adhesive sheet, and from the viewpoint of facilitating the formation of the concave portion and the flat surface on the surface (α) of the resin layer. 25 μm, more preferably 0.1 to 10 μm.

The fine particles used in the same state of the present invention are not particularly limited, and examples thereof include inorganic particles such as cerium oxide particles, oxidized metal particles, barium sulfate, calcium carbonate, magnesium carbonate, glass beads, and bentonite, or organic particles such as acrylic beads. Particles, etc.

Among these fine particles, one or more selected from the group consisting of cerium oxide particles, oxidized metal particles and bentonite are preferred, and cerium oxide particles are more preferred.

The cerium oxide particles used in the same state of the present invention may be any of dry cerium oxide particles and wet cerium oxide particles.

Further, the cerium oxide particles used in the same state of the present invention may be an organically modified cerium oxide surface-modified with an organic compound having a reactive functional group, or an inorganic surface treated with an inorganic compound such as sodium aluminate or sodium hydroxide. An organic-inorganic modified cerium oxide modified with cerium oxide, an organic-inorganic modified cerium oxide surface-treated with the organic compound and the inorganic compound, or an organic-inorganic hybrid material such as a decane coupling agent.

Further, the cerium oxide particles may be a mixture of two or more kinds.

The mass concentration of cerium oxide in the cerium oxide particles is preferably from 70 to 100% by mass, more preferably from 85 to 100% by mass, even more preferably from 90% to the total amount of cerium oxide particles (100% by mass). 100% by mass.

Further, the volume average secondary particle diameter of the cerium oxide particles used in the same state of the present invention is based on the viewpoint of improving the degassing property and bursting resistance of the adhesive sheet, and forming a concave portion and a flat surface based on the surface (α) of the resin layer. The viewpoint is preferably 0.5 to 10 μm, more preferably 1 to 8 μm, and still more preferably 1.5 to 5 μm.

Further, in the present invention, the value of the volume average secondary particle diameter of the cerium oxide particles is a value obtained by measuring a particle size distribution by a Coulter counting method using a Multisizer 3 or the like.

The oxidized metal particles are exemplified by, for example, a metal oxide selected from the group consisting of titanium oxide, aluminum oxide, boehmite, chromium oxide, nickel oxide, copper oxide, titanium oxide, zirconium oxide, indium oxide, zinc oxide, and composite oxides thereof. The particles and the like formed also include sol particles composed of the oxidized metals.

Examples of the bentonite include, for example, montmorillonite, aluminum bentonite, sodium hectorite, saponite, saponite, nontronite, and zinc bentonite.

In the adhesive sheet of the same state of the present invention, the resin layer has a mass retention rate of preferably 3 to 90% by mass, more preferably 5 to 80% by mass, more preferably 7 to 70% by mass after heating at 800 ° C for 30 minutes. It is preferably 9 to 60% by mass.

The mass retention rate can be regarded as indicating the content of the microparticles contained in the resin layer. (quality%).

When the mass retention rate is 3% by mass or more, an adhesive sheet excellent in deaeration property and burst resistance can be obtained. Further, in the production of the adhesive sheet of the present invention, it is easy to form a concave portion on the surface (α) of the resin layer.

On the other hand, when the mass retention rate is 90% by mass or less, the resin layer can be an adhesive sheet having high film strength, water resistance, and chemical resistance. Further, in the production of the adhesive sheet of the present invention, it is easy to form a flat surface on the surface (α) of the resin layer.

[Method of manufacturing adhesive sheet]

Next, a method of producing the adhesive sheet of the present invention will be described.

The method for producing the adhesive sheet of the present invention is not particularly limited. However, from the viewpoint of productivity, and from the viewpoint of facilitating the formation of the concave portion and the flat surface on the surface (α) of the resin layer, it is preferred to have at least the following steps (1) ) and (2) methods.

Step (1): forming a coating film (x') composed of a composition (x) containing a resin and having a content of fine particles of less than 15% by mass, and a composition (y) comprising 15% by mass or more of fine particles. Step of coating the film (y'); Step (2): simultaneously drying the coating film (x') and the coating film (y') formed in the step (1).

<Step (1)>

Step (1) is formed by containing a resin and the content of the fine particles is less than 15 The coating film (x') composed of the composition (x) of the mass% and the coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles.

The composition (x) is a material for forming the resin portion (X), and preferably contains the above-mentioned resin and a crosslinking agent, and may further contain an adhesion-imparting agent or the above-mentioned general-purpose additive.

Further, the composition (y) is a material for forming the particle portion (Y), but may further contain a resin, a crosslinking agent, an adhesion-imparting agent, and the above-mentioned general-purpose additive. The composition (y) containing a component other than the fine particles of the resin or the like is a material for forming the particle portion (Y) and also serves as a material for forming the resin portion (X).

(composition (x))

The resin contained in the composition (x) is exemplified by the resin constituting the resin portion (X), and is preferably an adhesive resin having a functional group, more preferably an acrylic resin (A) having the above functional group, and further The above acrylic copolymer (A1) is preferred.

The content of the resin in the composition (x) is usually 30% by mass or more, preferably 40% by mass or more, based on the total amount of the composition (x) (100% by mass (excluding the diluent solvent)). 50% by mass or more, more preferably 55% by mass or more, still more preferably 60% by mass or more, still more preferably 70% by mass or more, and more preferably 100% by mass or less, more preferably 99.9% by mass or less. More preferably, it is 95% by mass or less.

Further, as the crosslinking agent contained in the composition (x), for example In the above-mentioned resin portion (X), the composition (x) preferably contains at least one selected from the group consisting of a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent, and more preferably contains a metal. Chelate-based crosslinker.

Further, as a state of the present invention, the composition (x) preferably contains a metal chelate-based crosslinking agent and an epoxy resin from the viewpoint of improving the shape retention of the plurality of concave portions present on the surface (α) of the resin layer. Is a crosslinking agent.

When the composition (x) contains a metal chelate crosslinking agent and an epoxy crosslinking agent, the content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent in the composition (x) [ The metal chelate crosslinking agent/epoxy crosslinking agent is preferably 10/90 to 99.5/0.5, more preferably 50/50 to 99.0/1.0, and even more preferably 65/35 by mass ratio. ~98.5/1.5, and even better 75/25~98.0/2.0.

The content of the crosslinking agent is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, even more preferably 0.3 to 7.0 parts by mass, per 100 parts by mass of the resin contained in the composition (x).

The composition (x) is preferably an acrylic pressure-sensitive adhesive containing the acrylic resin (A) having the above functional group and the crosslinking agent (B), more preferably containing the acrylic copolymer (A1) and crosslinking. The acrylic adhesive of the agent (B). Further, the acrylic adhesive may further contain an adhesion-imparting agent or a general-purpose additive.

Further, the details of the above acrylic adhesive are as described above.

The composition (x) may also contain the above fine particles.

However, the content of the fine particles in the composition (x) is less than 15% by mass and less than the content of the resin contained in the composition (x).

The content of the fine particles in the specific composition (x) relative to the composition (x) The total amount (100% by mass (except for the dilution solvent)) is less than 15% by mass, preferably 0 to 13% by mass, more preferably 0 to 10% by mass, and even more preferably 0 to 5% by mass. %, more preferably 0% by mass.

(composition (y))

The material for forming the particle portion (Y) of the composition (y) is at least 15% by mass or more of the fine particles. However, it is preferable to contain the resin together with the fine particles from the viewpoint of dispersibility of the fine particles, and further preferably together with the resin. Contains a crosslinking agent. Further, the composition (y) may further contain an adhesion-imparting agent or a general-purpose additive.

Further, components other than the fine particles contained in the composition (y) (resin, crosslinking agent, adhesion-imparting agent, and general-purpose additive) are formed of the resin portion (X).

The fine particles contained in the composition (y) are exemplified above, but are preferably selected from the group consisting of cerium oxide particles, based on the formation of the void portion (Z) in the resin layer and the adhesion sheet having improved burst resistance. One or more kinds of oxidized metal particles and bentonite.

The content of the fine particles in the composition (y) is based on the viewpoint of easily forming an amorphous concave portion and a flat surface formed by the formation of the resin layer on the surface (α) of the resin layer, relative to the total amount of the composition (y). (100% by mass (excluding the diluent solvent)) is 15% by mass or more, preferably 20 to 100% by mass, more preferably 25 to 90% by mass, still more preferably 30 to 85% by mass, and even more preferably 35~80% by mass.

As the resin contained in the composition (y), for example, the above The resin contained in the composition (x) is the same, but preferably contains the same resin as the composition (x). Further, these resins may be used singly or in combination of two or more.

Further, the more specific resin contained in the composition (y) is preferably a resin having a functional group, more preferably an acrylic resin (A) having the above functional group, and more preferably the above acrylic copolymer ( A1).

The content of the resin in the composition (y) is usually from 0 to 85% by mass, preferably from 1 to 80% by mass, based on the total amount of the composition (y) (100% by mass (excluding the diluent solvent)). It is 5 to 75% by mass, more preferably 10 to 70% by mass, and even more preferably 20 to 65% by mass.

Further, the crosslinking agent contained in the composition (y) is exemplified by the same as the crosslinking agent contained in the resin portion (X). In the above, the composition (y) preferably contains at least one selected from the group consisting of a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent, and more preferably a metal chelate-based crosslinking agent. Further, in the same manner as in the present invention, the composition (y) preferably contains a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent.

Further, when the composition (y) contains a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent, the metal chelate-based crosslinking agent and the epoxy-based crosslinking agent in the composition (y) are suitable. The content ratio (mass ratio) is the same as the above composition (x).

The content of the crosslinking agent in the composition (y) is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, even more preferably 0.3% by mass based on 100 parts by mass of the resin contained in the composition (y). ~7.0 parts by mass.

(Formation method of coating film (x'), (y'))

Further, in the case of forming a coating film, in order to form a coating film easily, it is preferred to prepare a solvent in the composition (x) and (y) to prepare a solution form of the composition.

Examples of such a solvent are water or an organic solvent.

The organic solvent is exemplified by, for example, toluene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methanol, ethanol, isopropanol, tert-butanol, second butanol, ethyl hydrazine. Acetone, cyclohexanone, n-hexane, cyclohexane, and the like. Further, these solvents may be used alone or in combination of two or more.

The order of lamination of the coating films (x') and (y') formed in this step is not particularly limited, but it is preferably formed by laminating the coating film (x') on the coating film (y').

The method for forming the coating films (x') and (y') may be a method of sequentially forming a coating film (x') on the coating film (y') after forming the coating film (y'), and based on the viewpoint of productivity. A method of simultaneously coating a multi-layer coater to form a coating film (y') and a coating film (x') may be employed.

The applicator used in the successive formation is exemplified by, for example, a spin coater, a spray coater, a bar coater, a knife coater, a roll coater, a knife roll coater, a blade coater, and a gravure coat. Cloth, curtain flow applicator, die applicator, and the like.

The applicator used for simultaneous coating with a multilayer coater is exemplified by, for example, a curtain coater, a die coater, etc., but among these, a die coater is preferred from the viewpoint of workability.

Further, in the step (1), at least one of the coating film (x') and the coating film (y') is formed, and then it may be applied before the step (2). The pre-drying treatment does not allow the coating film to undergo a hardening reaction.

In the step (1), the drying temperature at the time of performing the pre-drying treatment is usually appropriately set within a temperature range in which the formed coating film is not cured, but preferably the drying temperature of the step (2) is not reached. The specific drying temperature as the "drying temperature which does not reach the step (2)" is preferably from 10 to 45 ° C, more preferably from 10 to 34 ° C, still more preferably from 15 to 30 ° C.

<Step (2)>

The step (2) is a step of simultaneously drying the coating film (x') and the coating film (y') formed in the step (1).

In this step, a resin layer containing the resin portion (X) and the particle portion (Y) is formed by simultaneously drying the formed coating film (x') and the coating film (y') while being on the surface of the resin layer ( α) forms a plurality of concave portions and flat surfaces.

The drying temperature in this step is preferably from 35 to 200 ° C, more preferably from 60 to 180 ° C, more preferably from 70 to 160 ° C, from the viewpoint of facilitating the formation of the concave portion and the flat surface on the surface (α) of the resin layer. More preferably 80~140 °C.

When the drying temperature is 35 ° C or higher, an adhesive sheet having good deaeration property can be obtained. On the other hand, when the drying temperature is 200 ° C or lower, the disadvantage of shrinkage of the base material or the release material of the adhesive sheet can be suppressed.

Further, the lower the drying temperature, the larger the difference in the height of the recess formed, and the number of recesses formed tends to decrease.

Further, the particle portion of the resin layer formed by this step The periphery of (Y) is liable to form a void portion (Z).

The void portion (Z) can be easily formed by using one or more selected from the group consisting of cerium oxide particles, oxidized metal particles, and bentonite as the fine particles contained in the composition (y).

Further, a layer (Xβ) mainly comprising a resin portion (X), a layer (Y1) containing 15% by mass or more of the particle portion (Y), and a main layer having the adhesive sheet 1a as shown in Fig. 1(a), and the like are produced. In the case of the adhesive sheet of the resin layer formed by the multilayer structure in which the layer (X) of the resin portion (X) is laminated in this order, the first and second aspects of the production methods described below are preferred.

In the following description of the manufacturing methods of the first and second aspects, the composition (xβ) and the composition (xα) are the same as the above-described composition (x) unless otherwise specified. Details of each component (resin, crosslinking agent, adhesion-imparting agent, general-purpose additive, diluent solvent, etc.) contained in (xβ) or (xα) (specific examples, preferred components, component contents, solid content concentration of each component) Etc.) is also the same as the above composition (x), and the "composition (y)" is also as described above.

[Manufacturing method of the first aspect]

The manufacturing method of the first aspect has at least the following steps (1A) and (2A): the step (1A): the composition comprising the resin and the content of the fine particles of less than 15% by mass on the substrate or the release material a coating film (xβ') composed of (xβ) and a composition (y) containing 15% by mass or more of the fine particles. a step of forming a coating film (y') and a coating film (xα') composed of a composition (xα) containing a resin and having a content of fine particles of less than 15% by mass; 2A): a step of drying the coating film (xβ'), the coating film (y'), and the coating film (xα') formed in the step (1A).

In the step (1A), it is preferred to apply the above solvent to the composition (xβ), the composition (y), and the composition (xα) to prepare a solution form of the composition, followed by coating.

The coating film (xβ'), the coating film (y'), and the coating film (xα') may be formed by forming a coating film (xβ') on the substrate or the release material, and then applying the coating film (xβ'). The coating film (y') is formed thereon, and the coating film (xα') is formed on the coating film (y'), and the method of sequentially forming the coating device described above may be simultaneously applied by using the above multilayer coater. The cloth forms a coating film (xβ'), a coating film (y'), and a coating film (xα').

Further, in the step (1A), one or more coating films of the coating film (xβ'), the coating film (y'), and the coating film (xα') are formed, and then may be applied before the step (2A). The pre-drying treatment does not allow the coating film to undergo a hardening reaction.

For example, after the respective coating films of the coating film (xβ'), the coating film (y'), and the coating film (xα') are formed, the pre-drying treatment may be performed each time, and the coating film (xβ') and the coating film may be formed. After the film (y') is subjected to the above pre-drying treatment together, a coating film (xα') is formed.

In the step (1A), the drying temperature at the time of performing the pre-drying treatment is usually set to a temperature range which does not harden the formed coating film. However, it is preferred that the drying temperature of the step (2A) is not reached. The specific drying temperature as the "drying temperature of the step (2A) is preferably from 10 to 45 ° C, more preferably from 10 to 34 ° C, still more preferably from 15 to 30 ° C.

Step (2A) is a step of simultaneously drying the coating film (xβ'), the coating film (y') and the coating film (xα') formed in the step (1A), and the drying temperature of the step is preferably in the above range. Step (2) is the same. By this step, a resin layer containing the resin portion (X) and the particle portion (Y) is formed.

[Production method of the second aspect]

As a manufacturing method of the second aspect, at least the following steps (1B) and (2B) are provided: Step (1B): on a layer (Xβ) mainly comprising a resin portion (X) provided on a substrate or a release material The order of the coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles, and the coating film (xα') composed of the composition (xα) containing the resin as a main component a step of forming a laminate; and a step (2B): simultaneously drying the coating film (y') and the coating film (xα') formed in the step (1B).

In the step (1B), the layer (Xβ) mainly containing the resin portion (X) can be formed by drying a coating film (xβ') composed of a composition (xβ) containing the resin as the main component.

In order to form the layer (Xβ) from the composition (xβ), the layer (Xβ) may contain a crosslinking agent, a general-purpose additive or the like in addition to the resin. Layer (Xβ) The content of the resin portion (X) is as described above.

As a method of forming the layer (Xβ), a coating film (xβ') composed of a composition (xβ) containing a resin as a main component can be formed on a substrate or a release material, and the coating film (xβ') can be dried. form.

The drying temperature at this time is not particularly limited, and is preferably 35 to 200 ° C, more preferably 60 to 180 ° C, still more preferably 70 to 160 ° C, and even more preferably 80 to 140 ° C.

Further, in this aspect, it is not formed on the coating film (xβ') but on the layer (Xβ) obtained after drying in the order of the coating film (y') and the coating film (xα'), and The first aspect described above is different.

In the step (1B), it is also preferred to mix the above solvent with the composition (y) and the composition (xα) to prepare a solution form of the composition, followed by coating.

The coating film (y') and the coating film (xα') may be formed by forming a coating film (y') on the coating layer (y') after forming a coating film (y') on the layer (Xβ). Alternatively, the method of sequentially forming the applicator described above may be used to simultaneously form a coating film (y') and a coating film (xα') by using the above multilayer coater.

Further, in the step (1B), after the coating film (y') is formed or after the coating film (y') and the coating film (xα') are formed, the step (2B) may be performed before the step (2B). The pre-drying treatment is performed to the extent that the coating film is subjected to a hardening reaction.

In the step (1B), the drying temperature at the time of performing the pre-drying treatment is usually set to a temperature range which does not harden the formed coating film. However, it is preferred that the drying temperature of the step (2B) is not reached. The specific drying temperature as the "drying temperature of the step (2B)" is preferably from 10 to 45 ° C, more preferably from 10 to 34 ° C, still more preferably from 15 to 30 ° C.

The step (2B) is a step of simultaneously drying the coating film (y') and the coating film (xα') formed in the step (1B), and the preferred drying range of the step is the same as the above step (2). By this step, a resin layer containing the resin portion (X) and the particle portion (Y) is formed.

[Examples]

The present invention will be more specifically described by the following examples, but the present invention is not limited to the following examples. Moreover, the physical property values in the following production examples and examples are values measured by the following methods.

<mass average molecular weight (Mw) of resin>

Using a gel permeation chromatography apparatus (product name "HLC-8020", manufactured by TOSOH Co., Ltd.), the measurement was carried out under the following conditions, and the values measured by standard polystyrene were used.

(measurement conditions)

. Pipe column: "TSK protection column HXL-L", "TSK gel G2500HXL", "TSK gel G2000HXL", "TSK gel G1000HXL" (both manufactured by TOSOH Co., Ltd.) are connected in sequence.

. Column temperature: 40 ° C

. Developing solvent: tetrahydrofuran

. Flow rate: 1.0mL/min

<Measurement of volume average secondary particle diameter of cerium oxide particles>

The volume average secondary particle diameter of the cerium oxide particles was determined by a Coulter counting method using a Multisizer 3 machine (manufactured by Beckman Coulter Co., Ltd.).

<Measurement of Thickness of Resin Layer>

The constant pressure thickness measuring device (model: "PG-02J", standard specification: according to JIS K6783, Z1702, Z1709) manufactured by TECLOCK Co., Ltd. was used.

Specifically, after measuring the total thickness of the adhesive sheet to be measured, the value of the thickness of the substrate or the release sheet measured in advance is referred to as "the thickness of the resin layer".

Manufacturing example x-1~x-4 (Preparation of solution of resin composition (xβ-1)~(xβ-2) and (xα-1)~(xα-2))

To the solution of the acrylic resin of the adhesive resin of the type and solid content described in Table 1, the type and the amount of the crosslinking agent and the adhesion-imparting agent described in Table 1 were added. Subsequently, the solution (xβ-1)~(xβ-2) and (xα-1)~(xα-2) of the resin composition having the solid content concentration shown in Table 1 were prepared by diluting with the dilution solvent described in Table 1. ).

Further, a solution of the resin composition (xβ-1)~(xβ-2) and The details of each component described in Table 1 used for the modulation of (xα-1)~(xα-2) are as follows.

<Acrylic resin solution>

. Solution (i): a solid component containing an acrylic resin (xi) (acrylic copolymer having a constituent unit of a raw material monomer obtained by a source of free BA/AA = 90/10 (% by mass), Mw: 630,000) A mixed solution of toluene and ethyl acetate having a concentration of 34.0% by mass.

. Solution (ii): an acrylic copolymer containing an acrylic resin (x-ii) (having a constituent unit of a raw material monomer obtained by a source free BA/AA = 90/10 (% by mass), Mw: 470,000) A mixed solution of toluene and ethyl acetate having a solid concentration of 37.0% by mass.

. Solution (iii): an acrylic copolymer containing an acrylic resin (x-iii) (having a source of 2EHA/VAc/AA = 75/23/2 (% by mass) of a raw material monomer, Mw: A mixed solution of toluene and isopropyl alcohol (IPA) having a solid concentration of 37.0% by mass.

. Solution (iv): an acrylic copolymer containing an acrylic resin (x-iv) having a constituent unit of a raw material monomer derived from a source of free BA/AA/HEA=94/3/3 (% by mass), Mw: 1 million) of an ethyl acetate solution having a solid concentration of 37.0% by mass.

Further, the abbreviation of the constituent raw material monomers of the above acrylic copolymer is as follows.

. BA: n-butyl acrylate

. 2EHA: 2-ethylhexyl acrylate

. AA: Acrylic

. VAc: vinyl acetate

. HEA: 2-hydroxyethyl acrylate

<crosslinker>

. Al-based cross-linking agent: product name "M-5A", manufactured by Soken Chemical Co., Ltd., aluminum chelate-based crosslinking agent, solid content concentration = 4.95 mass%.

. Epoxy-based crosslinking agent: "TETRAD-C" (product name, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was diluted with toluene to prepare a solution of an epoxy-based crosslinking agent having a solid concentration of 5 mass%.

<adhesive agent>

. Rosin ester type TF: rosin ester type polymer, Mw: less than 10,000, softening point: 85 °C.

. Styrene-based TF: a copolymer of a styrene-based monomer and an aliphatic monomer, Mw: less than 10,000, softening point: 95 °C.

<dilution solvent>

. Mixed solvent (1): a mixed solvent of toluene/isopropyl alcohol (IPA) = 65/35 (mass ratio).

. Mixed solvent (2): a mixed solvent of ethyl acetate/IPA=86/14 (mass ratio).

Manufacturing example f-1 (modulation of fine particle dispersion (f-1))

A solution (i) containing an acrylic resin containing the above acrylic resin (xi) (having an acrylic copolymer derived from a constituent unit of butyl acrylate (BA) and acrylic acid (AA), BA/AA = 90/ 10 (% by mass), Mw: 630,000) 100 parts by mass of a mixed solution of toluene and ethyl acetate having a solid concentration of 34.0% by mass (solid content: 34.0 parts by mass), and added as a fine particle of cerium oxide particles (product name) "NIPSIL E-200A", manufactured by TOSOH SILICA Co., Ltd., volume average secondary particle diameter: 3 μm) 51.0 parts by mass (solid content: 51.0 parts by mass) and toluene, and fine particles are dispersed to prepare an acrylic resin and cerium oxide particles. A fine particle dispersion (f-1) having a solid content concentration of 27% by mass.

Manufacturing example f-2 (modulation of fine particle dispersion (f-2))

Instead of the solution (i), with respect to the solution (ii) containing the above-mentioned acrylic resin (x-ii) (having an acrylic copolymer derived from a constituent unit of butyl acrylate (BA) and acrylic acid (AA), BA/ AA=90/10 (% by mass), Mw: 470,000) 100 parts by mass of a mixed solution of toluene and ethyl acetate having a solid content of 37.0% by mass (solid content: 37.0% by mass), and added as a fine particle of cerium oxide Particle (product name "NIPSIL E-200A", manufactured by TOSOH SILICA, Volume average average particle diameter: 3 μm) 55.5 parts by mass (solid content: 55.5 parts by mass) and toluene, and fine particles are dispersed to prepare a fine particle dispersion containing 30% by mass of the solid content of the acrylic resin and the ceria particles (f -2).

Manufacturing example y-1~y-2 (Preparation of coating liquid (y') to form coating liquid (y-1) to (y-2)

The coating liquid for forming a coating film (y') in which the solid content concentration described in Table 2 is prepared by adding the fine particle dispersion liquid, the acrylic resin solution, the crosslinking agent, and the diluent solvent in the types and the amounts described in Table 2, respectively. (y-1)~(y-2).

Further, the details of the respective components described in Table 2 used for preparation of the coating liquids (y-1) to (y-2) for coating film formation (y') are as follows.

<Microparticle dispersion>

. Dispersion liquid (f-1): A fine particle dispersion liquid (f-1) containing a solid content concentration of 27% by mass of the acrylic resin (x-i) and cerium oxide particles prepared in Production Example f-1.

. Dispersion liquid (f-2): A fine particle dispersion liquid (f-2) containing a solid content concentration of 30% by mass of the acrylic resin (x-ii) and cerium oxide particles prepared in Production Example f-2.

<Acrylic resin solution>

. Solution (i): a solid component containing an acrylic resin (xi) (acrylic copolymer having a constituent unit of a raw material monomer obtained by a source of free BA/AA = 90/10 (% by mass), Mw: 630,000) Concentration 34.0 quality A mixture of % toluene and ethyl acetate.

. Solution (ii): an acrylic copolymer containing an acrylic resin (x-ii) (having a constituent unit of a raw material monomer obtained by a source free BA/AA = 90/10 (% by mass), Mw: 470,000) A mixed solution of toluene and ethyl acetate having a solid concentration of 37.0% by mass.

<crosslinker>

. Al-based cross-linking agent: product name "M-5A", manufactured by Soken Chemical Co., Ltd., aluminum chelate-based crosslinking agent, solid content concentration = 4.95 mass%.

. Epoxy-based crosslinking agent: "TETRAD-C" (product name, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was diluted with toluene to prepare a solution of an epoxy-based crosslinking agent having a solid concentration of 5 mass%.

<dilution solvent>

. IPA/CHN: a mixed solvent of isopropyl alcohol (IPA) and cyclohexanone (CHN) (IPA/CHN=95/5 (mass ratio)).

Example 1~2 (1) Formation of coating film

The release film of the first release material (manufactured by LINTEC Co., Ltd., product name "SP-PET381031", 38 μm thick, on the surface of the PET film, which is provided with a polyoxynitride-based release agent layer), A solution (xβ-1) of the resin composition prepared in Production Example x-1 as described in Table 3 was applied from the release agent layer using a multilayer die coater (width: 250 mm) and a production example y- A coating solution (x-1) for forming a coating film (y') and a resin composition (xβ-1) prepared by the production example x-1 for forming a coating film (xα'), depending on the coating The order of the film (xβ'), the coating film (y'), and the coating film (xα') is simultaneously formed.

Moreover, the coating speed of each solution (coating liquid) for forming the coating film (xβ'), the coating film (y'), and the coating film (xα') and the coating amount of each coating film are as shown in Table 3. Recorded.

(2) Drying treatment

Next, the three-layer coating film (xβ'), the coating film (y'), and the coating film (xα') were simultaneously dried at a drying temperature of 100 ° C for 2 minutes to form a resin portion (X) and a particle portion (Y). The resin layer of the thickness shown in Table 3.

Further, in any of Examples 1 to 2, a plurality of concave portions and flat surfaces were visually observed on the surface (α) of the formed resin layer.

(3) Production of adhesive sheets without substrate and adhesive sheets with substrate

The surface (α) of the resin layer to be formed is laminated to the surface of the release agent layer of the release film of the second release material (product name "SP-PET386040" manufactured by LINTEC Co., Ltd.) to form a baseless layer. The material is adhered to the sheet.

After the substrate-free adhesive sheet prepared in the same manner was allowed to stand in an environment of 23 ° C for one week, the first release material was removed to expose the surface of the resin layer (β) to the polyethylene terephthalate of the substrate. A (PET) film (manufactured by TORAY Co., Ltd., product name "LUMIRROR T60 #50", thickness: 50 μm) was laminated to form an adhesive sheet with a substrate.

Example 3~4 (1) Formation of coating film

Multilayer nozzle coating on the surface of an aluminum vapor-deposited layer of polyethylene terephthalate (PET) film ("FNS MATT N50", 50 μm thick) made of aluminum vapor-deposited layer on one side The coating (width: 250 mm) was applied from the aluminum vapor-deposited layer, and the solution of the resin composition prepared in the production example x-2 described in Table 3 (xβ-2) and the coating prepared in the production example y-2 were simultaneously coated. a film (y-2) forming coating solution (y-2) and a solution of a resin composition prepared by the production examples x-3 to x-4 (xα-1) or (xα-2), depending on the coating film (xβ' The order of the coating film (y') and the coating film (xα') is simultaneously formed.

Further, the coating speed of each solution (coating liquid) for forming the coating film (xβ'), the coating film (y'), and the coating film (xα') and the coating of each coating film The amount is as shown in Table 3.

(2) Drying treatment

Next, the three-layer coating film (xβ'), the coating film (y'), and the coating film (xα') were simultaneously dried at a drying temperature of 100 ° C for 2 minutes to form a resin portion (X) and a particle portion (Y). The resin layer of the thickness shown in Table 3.

Further, in any of Examples 3 to 4, the plurality of concave portions and the flat surface were visually confirmed on the surface (α) of the formed resin layer.

(3) Production of adhesive sheets with substrate

The film was bonded to the surface of the release agent layer of a release film (manufactured by LINTEC Co., Ltd., product name "SP-PET 381031") to obtain a substrate-attached adhesive sheet.

Comparative example 1~4 (1) Production of embossed release paper

Formed from low density polyethylene resin on one side of fine paper (Sumitomo A 25 μm thick resin film made of the product name "SUMIKATHENE (L705)", melting point 106 °). Then, the surface of the resin film was adhered to the uneven surface of the metal engraved plate, and in this state, it was inserted between two rotating polyoxyethylene rubber rolls heated at 115 ° C, and the surface of the resin film was embossed.

A polyfluorene-based release agent (manufactured by LINTEC Co., Ltd., product name "Release similar to SP-PET1031") was applied to the surface of the resin film after the embossing, and then dried at 100 ° C for 1 minute to prepare a thickness of 110 μm. Embossed release paper.

Moreover, the unevenness forming surface of the metal engraving plate was used to form a concave portion and a flat surface of an individual shape on the surface (α) of the resin layer of the adhesive sheet produced in Comparative Examples 1 to 4.

(2) Production of substrate adhesive sheets

On the release agent layer of the embossed release paper prepared in the above (1), a solution (xβ-1) of the resin composition prepared in Production Example x-1 described in Table 1 was applied using an applicator, followed by 100 The resin layer was formed by drying at ° C for 1 minute to obtain the coating speed described in Example 1 of Table 3 and the coating amount of each coating film. Then, a PET film (manufactured by TORAY Co., Ltd., product name "LUMIRROR T60 #50", thickness: 50 μm) was laminated on the surface of the resin layer (α) to form an adhesive sheet with a substrate.

The substrate-free adhesive sheet or the base-attached adhesive sheet produced in the examples and the comparative examples was used for measurement or observation of the properties of the resin layer and the adhesive sheet of the adhesive sheet by the following method. These results are shown in Tables 4 and 5.

(1) Production of measurement samples

As shown in Fig. 4 (a), the alkali-free glass (product name "EAGLE XG", manufactured by Corning Incorporated) is attached to the adherend 101 having a smooth surface by a double-sided tape in order to remove the influence of the undulation of the adhesive sheet. The substrate of the adhesive sheet prepared in the examples and the comparative examples.

Next, the release material laminated on the surface (α) of the resin layer of the adhesive sheet was removed, and the surface (α) of the resin layer was exposed as a measurement sample.

<Is it possible to confirm the concave portion and the flat surface by visual inspection>

. Evaluation item (a): By visually observing the surface (α) of the resin layer exposed by the measurement sample, it was evaluated whether or not the presence of the concave portion and the flat surface on the surface (α) was visually confirmed by the following criteria.

A: The presence of the concave portion and the flat surface on the surface (α) can be confirmed by visual observation.

F: The presence of the concave portion and the flat surface on the surface (α) cannot be confirmed by visual observation.

(2) Image acquisition of the area (D) on the surface (α)

Using a digital microscope (magnification: 50 times), the surface of the resin layer (α) exposed by the above-mentioned measurement sample is arbitrarily selected from the adjacent surface of the photographing surface (α) in the direction A of FIG. 4(a), and the adjacent plural image The connected image is obtained by the image connection function of the digital microscope.

Also, at the time of shooting, more specifically, from the direction A of Fig. 4(a) The focus is moved sequentially above the portion that is visually judged to be a flat surface, and the portion having the focus first is photographed as a flat surface.

Next, in the obtained connected image, an area (D) surrounded by a rectangle having a length of 8 mm and a width of 10 mm is arbitrarily selected, and this is referred to as an "image of the area (D)".

Further, among the acquired connected images, an area (Q) surrounded by a square of 1 mm is selected arbitrarily, and this is set as an "image of the area (Q)".

Also, the shooting conditions of the digital microscope are as follows.

(measuring machine)

KYENCE Co., Ltd., product name "digital microscope VHX-5000", high resolution zoom lens VHX-ZST100 times

(measurement conditions)

. Epi-illumination: open

. Platform through lighting: off

. Lighting conversion: coaxial projection

. Edge emphasis: off

<Evaluation of the shape of the concave portion and the flat surface, etc.>

From the "image of the area (D)" obtained in the above (2), the following evaluation items (b1) to (b4) and (c1) to (c4) are observed, and the evaluation is performed on an individual basis.

The results of these evaluations are shown in Table 4.

<Evaluation item regarding the shape and position of the flat surface existing in the area (D)>

. Evaluation item (b1): The "image of the area (D)" obtained in the above (2) was observed, and the presence or absence of the concave portion and the amorphous flat surface was observed, and the evaluation was performed based on the following criteria. The evaluation results are shown in Table 4.

A: In the region (D), the presence of the concave portion and the amorphous plural flat surface is confirmed.

B: In the region (D), the presence of the concave portion and the plurality of flat surfaces was confirmed, but the flat surfaces confirmed were all shaped, and the existence of the amorphous flat surface could not be confirmed.

C: In the region (D), the presence of the concave portion and the amorphous flat surface cannot be confirmed.

In the above evaluation item (b1), observations regarding the following evaluations (b2) to (b4) and (c1) to (c4) were performed, and evaluation was performed on an individual basis. The results of these evaluations are shown in Table 4.

<Evaluation item regarding the shape and position of the flat surface existing in the area (D)>

. Evaluation item (b2): Whether or not there is a flat surface having a width which can select a region surrounded by a circle having a diameter of 100 μm or more by the following reference evaluation region (D).

In the A+: region (D), there is a flat surface having a wide area capable of selecting a region surrounded by a circle having a diameter of 200 μm.

A: In the region (D), there is a flat surface having a wide area capable of selecting a region surrounded by a circle having a diameter of 150 μm.

B: In the region (D), there is a choice of 100 μm in diameter. The flatness of the breadth of the area surrounded by the circle.

In the C: region (D), there is no flat surface having a wide area capable of selecting a region surrounded by a circle having a diameter of 100 μm.

. Evaluation item (b3): Whether or not the position where the plurality of flat faces exist in the following reference evaluation region (D) has periodicity.

A: The position where the complex flat surface exists does not have periodicity

F: The position where the complex flat surface exists has periodicity, or there is no complex flat surface in the region (D).

. Evaluation item (b4): Whether or not the flat surface shape existing in the following reference evaluation region (D) has a shape that becomes a fixed repeating unit.

A: The flat surface shape does not have a shape that becomes a fixed repeating unit.

F: The flat surface shape has a shape that becomes a fixed repeating unit.

(Evaluation item on the shape and position of the recess existing in the area (D))

. Evaluation item (c1): Whether or not an amorphous recess exists in the area (D) by the following reference.

A: There are amorphous recesses in the plural.

B: There is only one amorphous recess.

C: There is no amorphous recess.

. Evaluation item (c2): Whether or not the plurality of concave portions exist in the following reference evaluation region (D), and whether the position of the plurality of concave portions has a period Sex.

A: The position where the complex recess exists does not have periodicity

F: The position where the plurality of recesses exist has a periodicity, or the plural recesses do not exist in the region (D).

. Evaluation item (c3): Whether or not the shape of the concave portion existing in the following reference evaluation region (D) has a shape that becomes a fixed repeating unit.

A: The shape of the recess does not have a shape that becomes a fixed repeating unit.

F: The shape of the recess has a shape that becomes a fixed repeating unit.

(Evaluation item on the presence or absence of an amorphous recess in the area (Q))

. Evaluation item (c4): From the obtained "area (Q) image", it is evaluated whether or not the amorphous portion is present in the region (Q) by the following criteria.

A: In the region (Q), there are a plurality of amorphous recesses.

B: In the area (Q), there is only one amorphous recess.

C: In the region (Q), there is no amorphous recess.

(3) Determination of the area of the concave portion and the flat surface existing in the region (D)

Based on the "image of the region (D)" obtained in the above (2), the automatic area measurement was performed using the same digital microscope as described above, and the area of each concave portion and each flat surface existing in the region (D) was obtained.

Moreover, the automatic area measurement system uses the digital microscope and the visual image to be processed by the digital microscope and the image as needed in the area (D). After the value was obtained, the numerical value (area) of the obtained binarized image was measured, and the area of each concave portion and each flat surface was measured. When there are a plurality of concave portions and flat surfaces, the area measurement of the concave portion and the flat surface is performed.

Further, when it is not possible to determine whether or not the flat surface is visible by the visual observation of the image, the light-transmitting adherend having a smooth surface is applied to the surface of the resin layer (α) by the squeegee so as not to apply the load as much as possible. In the W direction of FIG. 4(b), the interface between the smooth surface 100a of the light-transmitting adherend 100 and the surface (α) 12a of the resin layer 12 was taken, and the attached portion was judged to be a flat surface.

In addition, the light-transmitting adherend 100 having the smooth surface 100a is made of an alkali-free glass (product name "EAGLE XG", manufactured by Corning Incorporated) in the same manner as the "adhered body having a smooth surface".

From the data of the area of each of the obtained concave portions and the area of each flat surface, various measurement values (average value, standard deviation, maximum value, minimum value, and the like) were calculated using a graph software (EXCEL, manufactured by Nippon Biotech Co., Ltd.).

The automatic area measurement conditions are as follows.

(Automatic area measurement conditions)

. Extraction mode: brightness (missing noise is weak)

. Extraction area: Rectangularly drawn by a numerical value (rectangular) with a length of 8 mm × a width of 10 mm

. Shaping of the extraction area: removal of particles (removal area of 100 μm ² or less)

Further, when it is not possible to determine whether or not the flat surface is visually recognized by the image, the light-transmitting adherend having a smooth surface is attached to the surface of the resin layer (α) by the squeegee as much as possible without applying a load. In the W direction of Figure 4(b), The interface between the smooth surface 100a of the light-transmitting adherend 100 and the surface (α) 12a of the resin layer 12 is photographed, and the portion of the surface (α) 12a to which the smooth surface 100a is attached is determined to be a flat surface.

<The ratio of the area occupied by the flat surface or the concave portion>

Calculate the area ratio (%) of the flat surface and the area ratio (%) of the concave portion for the total area of the area (D). The evaluation results are shown in Table 4.

The calculation or evaluation of the physical property values of the following evaluation items (d1) to (d2) and (e1) to (e2) is also performed. The results of these evaluations are shown in Table 4.

<Evaluation of the area of the flat surface and the recess existing in the area (D)>

. Evaluation item (d1): Whether or not a flat surface having an area of 0.2 mm ² or more is present in the following reference evaluation region (D).

A+: There is a flat surface having a complex area of 0.4 mm ² or more.

A: There is one flat surface having an area of 0.4 mm ² or more, and a plurality of flat surfaces having an area of 0.2 mm ² or more and less than 0.4 mm ² are present.

B+: A flat surface having a complex area of 0.2 mm ² or more and less than 0.4 mm ² .

B: There is one flat surface having an area of 0.2 mm ² or more and less than 0.4 mm ² .

C: The maximum area of the flat surface present in the area (D) is less than 0.2 mm ² .

. Evaluation item (d2): The area ratio of the amorphous flat surface existing in the area (D) of the total area of the flat surface existing in the area (D) was calculated and evaluated by the following criteria.

A+: The proportion of the area of the amorphous flat surface is 100%.

A: The proportion of the area of the amorphous flat surface is 90% or more and less than 100%.

B: The proportion of the area of the amorphous flat surface is 80% or more and less than 90%.

C: The proportion of the area of the amorphous flat surface is less than 80%.

. Evaluation item (e1): The area ratio of the concave portion having the largest area in the region (D) of the total area of the concave portion existing in the region (D) was calculated by the following formula.

[Area ratio (%) of the recess having the largest area] = [area of the recess having the largest area] / [total area of the recess] × 100

. Evaluation item (e2): The area ratio of the amorphous recess existing in the area (D) of the total area of the recess existing in the area (D) was calculated, and the evaluation was performed based on the following criteria.

A+: The proportion of the area occupied by the amorphous recess is 100%.

A: The proportion of the area occupied by the amorphous recess is 90% or more and less than 100%.

B: The proportion of the area occupied by the amorphous recess is 80% or more and less than 90%.

C: The proportion of the area occupied by the amorphous recess is less than 80%.

(4) Measurement and calculation of the physical property value of the flat surface (S) existing in the area (D) <About the skewness Sk value of the flat surface (S)>

Based on the values of the respective areas of the plurality of flat surfaces present in the region (D) measured in the above (2), the flat surface obtained by adding the relative number of times from the flat surface to the smaller relative area is 30% or less. More than one flat surface (S).

Next, for the area of each flat surface (S) to be screened, the normal state with respect to area and frequency of each flat surface (S) is calculated using the graph software (Japan Microsoft Corporation, EXCEL) based on the following equation (2). Skewness Sk value of the distribution curve.

In other words, the area of each of the obtained concave portions and the area data of each flat surface were arranged using a graphic software (EXCEL, manufactured by Nippon Bios. Co., Ltd.).

Then, from the data, the data of the "flat surface (S)" obtained by removing the flat surface obtained by adding the relative number of times from the flat surface to the smaller relative area is 30% or less. Further, the average value of the measured values of the area of the flat surface (S) was calculated.

Further, the standard deviation of the area of the flat surface (S) when the total area of the flat surface (S) is 100, and the skewness of the normal distribution curve with respect to the area and the frequency of the flat surface (S) are calculated. Sk value and kurtosis Ku value. The results of these calculations are shown in Table 4.

Next, using the graph software (Japan Microsoft Corporation, EXCEL) for the area of each flat surface (S) to be screened, the relative area (or circumference) of each flat surface (S) is calculated based on the following formula (2). The kurtosis Ku value is calculated based on the skewness Sk value of the normal distribution curve of the frequency based on the following formula (3).

In addition, the light-transmitting adherend 100 having the smooth surface 100a is the same as the "adhered body having a smooth surface", and an alkali-free glass (product name "EAGLE XG (registered trademark)", manufactured by Corning Incorporated) is used.

In the formula (2), n represents the number of flat faces (S), x _i represents each area (i: 1, 2, ... n) of each flat face (S), and μ represents the area of each flat face (S). The average value, s indicates the standard deviation of the specimen].

<About the kurtosis Ku value of the flat surface (S)>

Based on the values of the respective areas of the plurality of flat surfaces present in the region (D) measured in the above (3), the flat surface obtained by adding the relative number of times from the flat surface to the smaller relative area is 30% or less. More than one flat surface (S).

Next, for the area of each flat surface (S) to be screened, the normal state with respect to the area and frequency of each flat surface (S) is calculated using the graph software (Japan Microsoft Corporation, EXCEL) based on the following equation (3). The kurtosis Ku value of the distribution curve.

[In the formula (3), n represents the number of flat faces (S), x _i represents each area (i: 1, 2, ... n) of each flat face (S), and μ represents the area of each flat face (S). The average value, s indicates the standard deviation of the specimen].

<Evaluation of the existence of the concave portion of the surface (α) having the maximum height difference of 0.5 μm or more>

Using a scanning electron microscope (product name "S-4700" manufactured by Hitachi, Ltd.), the resin adhered to the substrate and the substrate prepared in the examples and the comparative examples were observed under the conditions of an acceleration voltage of 5 kV and a magnification of 500 times. Any area selected on the surface (α) of the layer surrounded by a rectangle having a length of 8 mm × a width of 10 mm (D) becomes a vertical plane cut region (D), and the height difference of each concave portion of the cross-section of the substrate-attached sheet is , get the profile image.

In addition to the cross-sectional image, it was evaluated whether or not there was a concave portion having a maximum height difference of 0.5 μm or more on the surface (α) 12a side by the following reference.

A: There is a recess having a maximum height difference of 0.5 μm or more.

F: There is no recess having a maximum height difference of 0.5 μm or more.

<Quality retention rate of resin layer of adhesive sheet>

After the monomer of the resin layer was obtained from the adhesive sheet, the quality of the resin layer before heating was measured. Next, the resin layer was placed in a muffle furnace (manufactured by DENKEN CORPORATION, product name "KDF-P90"), and heated at 800 ° C for 30 minutes. Next, the mass of the resin layer after heating was measured, and the mass retention rate of the resin layer was calculated by the following formula. The values are shown in Table 4.

Quality retention ratio (%) of the resin layer = [mass of the resin layer after heating] / [mass of the resin layer before heating] × 100

<degassing property>

The adhesive substrate with a length of 50 mm × a width of 50 mm is attached to the melamine coated plate of the adherend in such a manner as to generate air, and the squeegee is pressed against the periphery of the air to be strongly pressed. When pressed weakly twice. Next, it was observed whether or not air was accumulated after the attachment was performed by using a squeegee to remove air. The degassing properties of the respective adhesive sheets were evaluated by the following criteria. The evaluation results are shown in Table 4.

5: Air accumulation disappears when either weakly pressed or pressed.

4: When the pressure is weak, the air accumulation disappears. When the pressure is strong, most of the air accumulation will disappear, and the remaining air will disappear if it is pressed again.

3: When the pressure is weak, the air accumulation disappears. On the other hand, when pressed more strongly, there is a portion where a part of the air remains.

2: When the pressure is weak, most of the air accumulation will disappear, and the remaining air will disappear if it is pressed again. On the other hand, when the pressure is strong, residual air is accumulated.

1: Air accumulation remains when either weak pressure is pressed or when it is pressed.

<adhesion>

After the substrate-attached adhesive sheet prepared in the examples and the comparative examples was cut to a size of 25 mm × 300 mm in width, the surface of the resin layer of the adhesive sheet was (α) in an environment of 23 ° C and 50% RH (relative humidity). It was attached to a stainless steel plate (SUS304, No. 360 grinding) and allowed to stand in the same environment for 24 hours. After standing, the adhesion of each of the adhesive sheets was measured by a 180° peeling method at a tensile speed of 300 mm/min based on JIS Z0237:2000. The measurement results are shown in Table 4.

<Burst resistance>

A substrate adhesive sheet having a length of 50 mm and a width of 50 mm is attached to a polymethyl methacrylate sheet having a length of 70 mm, a width of 150 mm, and a thickness of 2 mm (manufactured by Mitsubishi Rayon Co., Ltd., product name "ACRYLITE L001"). The test sample was prepared by pressing firmly with a squeegee.

The test sample was allowed to stand at 23 ° C for 12 hours, and then allowed to stand in a hot air dryer at 80 ° C for 1.5 hours, and further allowed to stand in a hot air dryer at 90 ° C for 1.5 hours, and the state of occurrence of burst after heating promotion was visually observed. The burst resistance of each of the adhesive sheets was evaluated by the following criteria. The evaluation results are shown in Table 4.

A: The burst was not confirmed at all.

B: Partial confirmation of bursting.

C: Fully confirmed to burst.

Since the adhesive sheets of Examples 1 to 4 have the concave portions defined by the requirements (Ii) and (Iii), and the flat surfaces, they have excellent degassing properties that can easily remove air accumulation, and the adhesive characteristics can be balanced. A good display of the results.

On the other hand, the adhesive sheets of Comparative Examples 1 to 4 were inferior in degassing properties as compared with the adhesive sheets of the examples.

Fig. 5 (a) and Figs. 6 to 12 show the adhesion of the examples 1 to 4 and the comparative examples 1 to 4 from the surface (α) side using a digital microscope, respectively. A binarized image of an image obtained by a region (D) surrounded by a length of 8 mm × a width of 10 mm, which is an optional surface (α) of the resin layer of the sheet.

That is, the image lengths of FIG. 5(a) and FIGS. 6 to 12 are "8 mm" and the width is "10 mm".

Further, in these binarized images, the black portion is a flat surface, and the white portion corresponds to a concave portion.

Fig. 5(b) is a cross-sectional image obtained by observing the cross section of the adhesive sheet prepared in Example 1 using a scanning microscope.

[Industrial availability]

The adhesive sheet of the same state of the present invention can be used for surface protection for identification, decoration, coating, metal sheet, etc., and can be used as an adhesive sheet having a large attachment area.

1a, 1b, 2a, 2b‧‧‧ adhesive sheets

11‧‧‧Substrate

12‧‧‧ resin layer

12a‧‧‧Surface (α)

12b‧‧‧Surface (β)

(X)‧‧‧Resin part (X)

(Y)‧‧‧Parts of particles (Y)

(Xα)‧‧‧ mainly consists of the layer of the resin part (X) (Xα)

(Xβ)‧‧‧ mainly consists of the layer of the resin part (X) (Xβ)

(Y1) ‧ ‧ layers containing more than 15% by mass of the particle fraction (Y) (Y1)

13‧‧‧ recess

14‧‧‧flat surface

21‧‧‧ peeling material

22‧‧‧ peeling material

Claims (19)

An adhesive sheet having a resin layer on a substrate or a release material, and an adhesive sheet having adhesiveness at least on a surface (α) of the resin layer opposite to the side on which the substrate or the release material is provided, The surface (α) of the resin layer has a concave portion and one or more flat surfaces (f1), and the flat surface (f1) is selected to be surrounded by a circle having a diameter of 100 μm by observation from the surface (α) side. The breadth of the range, and the shape of the flat surface is amorphous. The adhesive sheet according to claim 1, wherein the surface (α) of the resin layer has one or more flat surfaces (f2) having an area of 0.2 mm ² or more. An adhesive sheet according to claim 1 or 2, wherein in the arbitrarily selected region (D) of 8 mm long by 10 mm wide on the surface (α), the total area of the recess existing in the field (D) is 100 %, there is a recess having an area of 70 to 99.99%. The adhesive sheet according to any one of claims 1 to 3, wherein in the arbitrarily selected region (D) of 8 mm long by 10 mm wide on the surface (α), a plurality of flat faces exist, and are removed from the plural If the area of the flat surface that is present is smaller, the flat surface (S) obtained by adding the flat surface having the cumulative relative number of relative times of 30% or less is added, and the normal distribution curve with respect to the area and the frequency is respectively The skewness Sk value is 1.0 or more. The adhesive sheet according to claim 4, wherein a kurtosis Ku value of each of the one or more flat faces (S) with respect to the normal distribution curve of the area and the frequency is 1.8 or more. The adhesive sheet according to any one of claims 1 to 5, wherein the flat surface is plural on the surface (α), and the position where the plurality of flat surfaces exist does not have periodicity. The adhesive sheet according to any one of claims 1 to 6, wherein the concave portion has a height difference of at most 0.5 μm or more. The adhesive sheet according to any one of claims 1 to 7, wherein the concave portion is not formed by using a release material having an embossed pattern. The adhesive sheet according to any one of claims 1 to 8, wherein the resin layer comprises a resin-containing resin portion (X) as a main component and a fine particle portion (Y) composed of fine particles. The adhesive sheet according to claim 9, wherein the mass retention rate after heating the resin layer at 800 ° C for 30 minutes is 3 to 90% by mass. The adhesive sheet of claim 9 or 10, wherein the resin contained in the resin portion (X) contains an adhesive resin. The adhesive sheet according to any one of claims 9 to 11, wherein the resin portion (X) further contains one or more selected from the group consisting of a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent. The adhesive sheet according to any one of claims 9 to 12, wherein the fine particles are one or more selected from the group consisting of cerium oxide particles, oxidized metal particles, and bentonite. The adhesive sheet according to any one of claims 9 to 13, wherein the surface (β) of the resin layer provided on the side of the substrate or the release material has adhesiveness. An adhesive sheet according to any one of claims 1 to 14, wherein the front The resin layer is provided on the side where the substrate or the release material is provided, and the layer (Xβ) mainly containing the resin portion (X), the layer (Y1) containing 15% by mass or more of the particle portion (Y), and mainly the resin portion. A multilayer structure in which the layers (Xα) of (X) are laminated in this order. The adhesive sheet according to claim 15, wherein the layer (Xβ) is a layer formed of a composition (xβ) containing a resin and having a content of fine particles of less than 15% by mass, and the layer (Y1) is composed of 15% by mass or more of the fine particles. The layer formed by the composition (y), the layer (Xα) is a layer formed of a composition (xα) containing a resin and having a content of fine particles of less than 15% by mass. A method for producing an adhesive sheet, which is a method for producing an adhesive sheet according to any one of claims 1 to 16, and has at least the following steps (1) and (2); and step (1): forming a resin containing resin The coating film (x') composed of the composition (x) having a fine particle content of less than 15% by mass and the coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles Step (2): a step of drying the coating film (x') and the coating film (y') formed in the step (1) at the same time. A method for producing an adhesive sheet, which is a method for producing an adhesive sheet according to claim 17, and has at least the following steps (1A) and (2A); and step (1A): on a substrate or a release material, according to Contains resin and a coating film (xβ') composed of a composition (xβ) having a content of fine particles of less than 15% by mass, a coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles, and a step of laminating a coating film (xα') composed of a composition (xα) containing a resin and having a content of fine particles of less than 15% by mass; and step (2A): simultaneously forming the step (1A) The coating film (xβ'), the coating film (y'), and the coating film (xα') are dried. A method for producing an adhesive sheet, which is a method for producing an adhesive sheet according to claim 17, and has at least the following steps (1B) and (2B); and step (1B): on a substrate or a release material. The coating film (y') composed of the composition (y) containing 15% by mass or more of the fine particles, and the content of the microparticles containing less than 15 in the layer (Xβ) mainly containing the resin portion (X). a step of laminating the coating film (xα') composed of the mass % of the composition (xα); and the step (2B): simultaneously applying the coating film (y') formed by the step (1B) and the coating film (xα') a step of drying.