JP2020093548A - Decorative sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative sheet capable of imparting a design which looks like a rainbow even when a resin molded product has a curved surface portion. SOLUTION: A base material layer 1 and a surface protective layer 2 having an ionizing radiation curable resin are provided, and the surface protective layer 2 has an unevenness spacing S of 0 on a main surface opposite to the base material layer side. A decorative sheet having a concavo-convex structure having a height difference H of .5-7.5 μm and a concavo-convex height difference H of 0.2 μm or more. [Selection diagram] Fig. 1

Description

The present disclosure relates to a decorative sheet and a decorative resin molded product decorated with the decorative sheet.

BACKGROUND ART A decorative resin molded product obtained by laminating a decorative sheet on the surface of a resin molded product is used for vehicle interior parts, building material interior materials, home appliance housings, etc. (Patent Document 1).

With the diversification of consumer needs, decorative resin molded products with various designs are required, and one of them is a decorative resin molded product with a rainbow design on the surface. be able to. As a decorative resin molded product having a rainbow pattern design on such a surface, a resin product that is subjected to a decorating method to form fine irregularities on the surface to give a rainbow-colored design It is disclosed in Patent Document 2.

Further, a decorative film having an extensibility capable of following a three-dimensional curved surface without impairing the three-dimensional design is known. For example, Patent Document 3 is a decorative film having at least a resin film provided with a design surface that expresses a three-dimensional design, and the design surface has a region in which a plurality of linear fine irregularities extend in parallel. A plurality of decorative films are disclosed.

Japanese Unexamined Patent Publication No. 2018-058222 JP, 2010-105242, A JP, 2018-123220, A

However, when the present inventors have decorated a resin molded product having a curved surface portion with a decorative sheet capable of giving a rainbow-colored design to the surface, there is a problem with the flat surface portion. Although it does not occur, we newly found that there is a problem that the design that looks rainbow-colored on the curved surface becomes unclear or disappears.

The present disclosure provides a design in which the surface looks rainbow-colored (hereinafter, rainbow design) not only on the flat surface portion of the resin molded product but also on the curved surface portion even when the resin molded product has a curved surface portion. The main purpose of the present invention is to provide a decorative sheet that can be used.

Further, the present disclosure mainly aims to provide a decorative sheet having high antiglare properties.

In order to solve the above problems, the inventors of the present invention have diligently studied, and when the decorative sheet is formed by placing the decorative sheet on the curved surface of the resin molded product by a method such as insert molding, the curved surface part is formed. In the above, since the decorative sheet is stretched, the uneven structure of the decorative sheet surface is also stretched, and as a result, in the curved surface portion of the resin molded product, the uneven portion causes interference for expressing the design of the rainbow pattern. The present invention has been completed by finding out that the phenomenon cannot occur.

That is, the present disclosure is a decorative sheet comprising a base material layer and a surface protection layer that is disposed on one main surface side of the base material layer and has an ionizing radiation curable resin, wherein the surface protection layer is , The main surface on the side opposite to the base material layer side has a concavo-convex structure, the concavo-convex interval of the concavo-convex structure is 0.5 μm or more and 7.5 μm or less, and the height difference of the concavo-convex structure of the concavo-convex structure is 0. A decorative sheet having a thickness of 2 μm or more is provided.

Further, the present disclosure is a decorative resin molded article having a resin molded article having a curved surface portion, and a decorative sheet disposed on at least the curved surface portion of the resin molded article, wherein the decorative sheet is A decorative resin molded product, which is the above-mentioned decorative sheet, in which the resin molded product and the base material layer side of the decorative sheet are arranged to face each other.

In order to solve the above problems, the inventors of the present invention have diligently studied and found that the uneven structure of the surface protective layer has a specific structure, whereby a decorative sheet with high antiglare property can be obtained, The present invention has been completed.

That is, the present disclosure is a decorative sheet comprising a base material layer and a surface protection layer that is disposed on one main surface side of the base material layer and has an ionizing radiation curable resin, wherein the surface protection layer is Has a concavo-convex structure on the main surface on the side opposite to the base material layer side, the area ratio of the flat portion at the top of the concavo-convex structure is 10% or less, and the side wall angle of the concavo-convex structure is 45°. A decorative sheet having an angle of 90° or more is provided.

Further, the present disclosure is a decorative resin molded article having a resin molded article and a decorative sheet arranged on one main surface side of the resin molded article, wherein the decorative sheet is the above-mentioned decorative sheet. Provided is a decorative resin molded product which is a sheet and in which the resin molded product and the base material layer side of the decorative sheet are arranged to face each other.

The decorative sheet of the present disclosure can give a rainbow design to a resin molded product even when the resin molded product has a curved surface portion. Further, the decorative sheet of the present disclosure has high antiglare property.

It is a schematic sectional drawing which shows an example of the decoration sheet of this indication. FIG. 4 is a top view of the surface protection layer on the side of the uneven structure showing an example of the arrangement of the uneven structure in the present disclosure. It is a schematic sectional drawing which illustrates the surface protection layer in this indication. It is a schematic sectional drawing which illustrates the decoration sheet of this indication. It is a schematic sectional drawing which shows another example of the decoration sheet of this indication. It is a process flow figure which manufactures the decoration sheet of this indication. It is a schematic diagram which shows an example of the decorative resin molded product of this indication. It is a schematic sectional drawing which illustrates the decoration sheet of this indication.

The present disclosure relates to a decorative sheet and a decorative resin molded product. Hereinafter, each will be described in detail. Note that the present disclosure can be implemented in many different modes, and should not be construed as being limited to the description of the embodiments below. Further, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each member as compared with the embodiment, but this is merely an example, and the interpretation of the present disclosure Is not limited. In the specification and the drawings, the same elements as those described above with reference to the drawings already described are denoted by the same reference numerals, and detailed description thereof may be appropriately omitted.

In the present specification, in expressing an aspect in which another member is arranged on a certain member, when simply expressed as “above” or “below”, it is in contact with a certain member unless otherwise specified. This includes both the case where another member is arranged immediately above or below and the case where another member is arranged above or below a certain member via another member. Further, in the present specification, in expressing an aspect in which another member is arranged on a certain member, when simply expressed as “on a surface”, unless directly stated otherwise, so as to be in contact with a certain member, directly or This includes both a case where another member is arranged immediately below and a case where another member is arranged above or below a certain member via another member.

A-1. Decorative sheet The decorative sheet of the present disclosure is a decorative sheet that is provided with a base material layer and a surface protective layer that is disposed on one main surface side of the base material layer and has an ionizing radiation curable resin, The surface protective layer has a concavo-convex structure on the main surface on the side opposite to the base layer side, and the concavo-convex interval of the concavo-convex structure is 0.5 μm or more and 7.5 μm or less. The feature is that the height difference is 0.2 μm or more.

According to the present disclosure, since the concavo-convex structure has a specific structure, it is possible to provide a decorative sheet that can be provided with a rainbow design even on a curved surface portion of a resin molded product. The present inventors have drawn the above-mentioned decorative sheet at a curved surface portion when molding a resin molded product having a decorative sheet arranged on its surface (hereinafter, may be referred to as a decorative resin molded product). Even in such a case, the design of the rainbow pattern is exhibited as long as it has a concavo-convex structure in which the interval of the concavities and convexities is 0.5 μm or more and the height difference of the concavities and convexities is 0.1 μm or more on the curved surface of the decorative resin molded product. I found out that. Further, it was found that the design of the rainbow pattern can be seen without being thin if the interval between the irregularities is about 15 μm or less.

In the present disclosure, the uneven structure in the decorative sheet is such that the uneven intervals are 0.5 μm or more and 7.5 μm or less, and the unevenness of the uneven structure is 0.2 μm or more, whereby a resin molded product is obtained. Even when the decorative sheet provided for the curved surface part is stretched, the interval and height difference of the unevenness of the uneven structure can be within the range where the design of the rainbow pattern is developed on the surface, whereby the resin molded article Even if it is a curved surface, it has an effect that a rainbow design can be applied without any problem.

The decorative sheet of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the decorative sheet of the present disclosure. The decorative sheet 10 of the present disclosure includes at least a base material layer 1 and a surface protective layer 2 made of an ionizing radiation curable resin. The surface protective layer 2 has a concavo-convex structure on the surface opposite to the base material layer 1 side, and the interval and height difference of the concavo-convex structure of the concavo-convex structure are within the ranges described above.
Hereinafter, each member of the decorative sheet of the present disclosure will be described in detail.

1. Surface protection layer (1) Concavo-convex structure The surface protection layer in the present disclosure is provided with a concavo-convex structure on the surface opposite to the base layer side. The interval of the unevenness of the uneven structure is 0.5 μm or more and 7.5 μm or less. In such a range, the design of the rainbow pattern on the surface can be visually recognized not only on the flat surface portion on which the decorative sheet is arranged but also on the curved surface portion when the decorative resin molded product is formed. On the other hand, when the interval of the unevenness of the uneven structure is less than 0.5 μm, the design of the rainbow pattern may not be visible even on the flat surface. The design of the rainbow pattern may not be confirmed.

In the present disclosure, the interval of the unevenness of the uneven structure may be 0.5 μm or more and 7.5 μm or less as described above, but is preferably 0.5 μm or more and 5.0 μm or less. Within such a range, the design of the rainbow pattern on the surface can be obtained even in a flat portion which is not stretched when placed on a resin molded product, or in a curved surface portion which is stretched by about 3 times. Is visible.

Here, in the present disclosure, the “distance between irregularities” means the distance S in FIG. 1, that is, the distance between the tops of two adjacent convex portions. In addition, as the above-mentioned “space between irregularities”, 20 pairs of adjacent two convex portions are randomly selected, and the average value of the distances between the top portions is selected. The term "top" as used herein refers to a portion of the convex portion that is at a distance from the surface of the base material layer that is closest to the surface protective layer. If the top is flat, it indicates the center of gravity of the flat surface. is there.

Further, in the present disclosure, the height difference of the unevenness of the uneven structure is 0.2 μm or more. When the thickness is 0.2 μm or more, the design of the rainbow pattern can be visually recognized even when it is stretched about twice when placed on a resin molded product having a curved surface portion. The height difference of the irregularities in the present disclosure is preferably 0.3 μm or more. This is because the design of the rainbow pattern can be seen even when it is stretched about three times when placed on a resin molded product having a curved surface portion. In addition, the upper limit of the height difference of the uneven structure in the present disclosure is not particularly limited, but can be set to about 5 μm due to a manufacturing limit or the like.

Here, the “height difference of the unevenness” of the uneven structure in the present disclosure is indicated by the distance H in FIG. 1. That is, in the peak of the convex portion and the valley of the concave portion in the surface protective layer (the portion closest to the surface of the base material layer on the surface protective layer side, where the valley is flat indicates the center of gravity of the flat surface). , The difference in the distance from the surface of the base material layer on the surface protective layer side. Further, as for the “height difference of unevenness”, 20 pairs of adjacent peaks and valleys are randomly selected, and the difference in the distances of these 20 pairs is measured, and the average value is obtained.

The above-mentioned “concavo-convex interval” and “height difference between concavities and convexities” can be measured by observing a cross section with an SEM or measuring a profile with a laser microscope. The shape of the concavo-convex structure described below can also be measured by the above method.

The cross-sectional shape of the concavo-convex structure in the present disclosure is not particularly limited as long as the reflected light becomes diffracted light and the rainbow design can be visually recognized by interference. For example, the shape obtained by cutting the convex portion of the concavo-convex structure in a cross section perpendicular to the surface of the base material layer may be a triangle (isosceles triangle, equilateral triangle), trapezoid, sinusoidal shape, or the like. For example, in FIG. 3A, the cross-sectional shape of the uneven structure in the surface protection layer 2 is a trapezoid. Further, in FIG. 3B, the cross-sectional shape of the concavo-convex structure in the surface protective layer 2 is a triangle with two oblique sides having the same length (isosceles triangle), and in FIG. The cross-sectional shape of the concavo-convex structure is a triangle whose two hypotenuses have different lengths. “Two hypotenuses have the same length” means that the difference in length between the two hypotenuses is less than 1 μm. On the other hand, “the lengths of the two hypotenuses are different” means that the difference between the lengths of the two hypotenuses is 1 μm or more. Further, in FIG. 3D, the cross-sectional shape of the concavo-convex structure in the surface protective layer 2 is wavy.
Further, the convex portion may have a conical shape, a truncated cone shape, a polygonal pyramid shape, or a polygonal truncated pyramid shape, and has an elliptical or rectangular shape in plan view, specifically, the convex portion has a streak shape. It may be formed.

Further, in FIG. 3A, the uneven structure in the surface protective layer 2 has a flat portion 5 at the top.
When the area of the flat portion 5 is large, the influence of reflection by the flat portion 5 becomes large, and the antiglare property deteriorates. Therefore, the area of the flat portion 5 is preferably small. In particular, the design of the rainbow pattern has a high design property, but on the other hand, a viewer tends to feel glare. On the other hand, by reducing the area of the flat portion 5, both design and antiglare properties can be achieved. Here, a flat surface of the uneven structure including the flat portion 5 is assumed, and the ratio of the total area of the flat portion 5 to the total area of the flat surface is defined as the area ratio of the flat portion 5. The area ratio of the flat portion 5 is, for example, 10% or less, 8% or less, 6% or less, 4% or less, or 2% or less. ..

Further, in FIG. 3A, the convex portion of the uneven structure in the surface protective layer 2 has the side wall portion 6.
When the angle formed by the direction in which the side wall portion 6 extends and the horizontal direction (direction orthogonal to the thickness direction) is θ, θ is, for example, 45° or more, may be 60° or more, and may be 75°. It may be more than. If θ is too low, high antiglare property may not be obtained. On the other hand, θ is, for example, 90° or less. Further, as shown in FIGS. 3B and 3C, the convex portion of the concavo-convex structure may have the first side wall portion 61 and the second side wall portion 62. When the convex portion of the concavo-convex structure has the first side wall portion 61 and the second side wall portion 62, at least one of the angles θ is preferably in the above range, and both angles θ are in the above range. Is more preferable. Further, as shown in FIG. 3(A), the side wall portion 6 may have a linear sectional shape, and as shown in FIG. 3(D), the side wall portion 6 may have a curved sectional shape. Good. In the latter case, the angle θ of the side wall portion 6 can be obtained from the approximate straight line.

The arrangement of the concavo-convex structure of the present disclosure is not particularly limited as long as it is possible to visually recognize the design of the rainbow pattern by the interference of diffracted light, but it is usually arranged regularly, and among them, one-dimensional lattice or two It is preferable that they are regularly arranged in a three-dimensional lattice. In particular, as shown in FIG. 2, it is preferable that the concavo-convex structure of the surface protective layer 2 is regularly arranged in a one-dimensional lattice shape. That is, the concavo-convex structure of the surface protection layer 2 extends along the first direction (longitudinal direction), and the convex portions and the concave portions are alternately arranged along the second direction intersecting the first direction. Preferably. When arranged in a one-dimensional lattice, the change in appearance of the rainbow pattern due to stretching in the longitudinal direction is small. This phenomenon results from the fact that the appearance of the rainbow pattern depends more strongly on the interval of the unevenness than on the depth (height difference) of the unevenness of the uneven structure. Furthermore, when the decorative sheet is placed on a resin molded product having a curved surface portion, the extending direction of the decorative sheet at the most conspicuous place is preferably the longitudinal direction of the concavo-convex structure arranged in a one-dimensional lattice. .. Note that the uneven structure of the present disclosure may be arranged randomly so that the design of the rainbow pattern can be visually recognized by interference.

(2) Material The surface protective layer in the present disclosure contains an ionizing radiation curable resin, and is usually formed only of the ionizing radiation curable resin. Here, the ionizing radiation-curable resin is a resin that is crosslinked and cured by irradiation with ionizing radiation, and specifically, has a polymerizable unsaturated bond or an epoxy group in the molecule, a prepolymer, an oligomer. , And a monomer obtained by curing an ionizing radiation curable resin composition in which at least one of them is appropriately mixed. Here, the ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking a molecule, and usually ultraviolet rays (UV) or electron beams (EB) are used. Electromagnetic waves such as rays and γ rays, and charged particle rays such as α rays and ion rays are also included. The “curable resin” in the present disclosure may include a resin before curing (uncured resin), a semi-cured resin, and a resin after cured (cured resin). Resins are preferred.

As the monomer used in the ionizing radiation curable resin composition, a (meth)acrylate monomer having a radically polymerizable unsaturated group in the molecule is preferable, and a polyfunctional (meth)acrylate monomer is particularly preferable. The polyfunctional (meth)acrylate monomer may be a (meth)acrylate monomer having two or more (two or more) polymerizable unsaturated bonds, preferably three or more (three or more functional) polymerizable unsaturated bonds in the molecule. With regard to the polyfunctional (meth)acrylate, known polyfunctional (meth)acrylates can be mentioned, and thus the description of specific examples is omitted here.

Further, as the above-mentioned oligomer used for the ionizing radiation-curable resin composition, a (meth)acrylate oligomer having a radically polymerizable unsaturated group in the molecule is suitable, and among them, two polymerizable unsaturated bonds are included in the molecule. A polyfunctional (meth)acrylate oligomer having the above (bifunctional or more) is preferable. Examples of the polyfunctional (meth)acrylate oligomer include polycarbonate (meth)acrylate, acrylic silicone (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate. , Polybutadiene (meth)acrylate, silicone (meth)acrylate, oligomer having a cationically polymerizable functional group in the molecule (for example, novolac type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.) and the like. .. Here, the polycarbonate (meth)acrylate is not particularly limited as long as it has a carbonate bond in the polymer main chain and a (meth)acrylate group at the terminal or side chain, and for example, polycarbonate polyol (meth) It can be obtained by esterification with acrylic acid. The polycarbonate (meth)acrylate may be, for example, urethane (meth)acrylate having a polycarbonate skeleton. As the polyfunctional (meth)acrylate oligomer, a known polyfunctional (meth)acrylate oligomer can be used, and therefore a description of specific examples is omitted here.

Among the above-mentioned ionizing radiation curable resins, it is preferable to use a polycarbonate (meth)acrylate from the viewpoint of obtaining excellent three-dimensional moldability. Further, it is preferable to use a combination of polycarbonate (meth)acrylate and urethane (meth)acrylate.

The surface protective layer may contain various additives depending on desired physical properties to be provided in the surface protective layer. As the additive, for example, a weather resistance improver such as an ultraviolet absorber or a light stabilizer, an abrasion resistance improver, a polymerization inhibitor, a crosslinking agent, an infrared absorber, an antistatic agent, an adhesion improver, a leveling agent, Examples include thixotropic agents, coupling agents, plasticizers, defoamers, fillers, solvents, colorants and the like.

(3) Others The thickness of the surface protective layer in the present disclosure is not particularly limited, but is preferably 2 μm or more and 20 μm or less, more preferably 2 μm or more and 15 μm or less, and further preferably 2 μm or more and 12 μm or less. This is because if the thickness in such a range is satisfied, it becomes thicker than the height difference of the unevenness of the uneven structure, and the uneven structure can be formed. Further, it is because sufficient physical properties as a surface protective layer such as scratch resistance and weather resistance can be obtained, and the surface protective layer can be easily formed using an ionizing radiation curable resin. Here, the thickness of the surface protective layer refers to the distance from the main surface of the surface protective layer on the base material layer side to the apex of the convex portion (that is, the maximum thickness of the surface protective layer).
The surface protective layer is preferably transparent from the viewpoint of curability and design of the resin.

2. Base Material Layer The decorative sheet of the present disclosure has a base material layer. The base material layer retains the shape of the decorative sheet and functions as a support for supporting the surface protective layer and the like. Further, when the decorative sheet is arranged on the surface of the resin molded product described below, the base material layer preferably has a function of adhering to the surface of the resin molded product.

The base material layer is not particularly limited, but is preferably a resin film.
As the resin forming the resin film, those having three-dimensional moldability are preferable, and the resin can be appropriately selected according to the aspect of the resin molded product on which the decorative sheet is arranged, and usually thermoplastic resin is selected. ..

Examples of such a thermoplastic resin include acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-styrene-acrylic acid ester resin, acrylic resin, polyolefin resin such as polypropylene and polyethylene, polycarbonate resin, vinyl chloride resin. , Polyethylene terephthalate (PET) resin and the like. In the base material layer, only one kind of the above-mentioned thermoplastic resins may be used, or two or more kinds thereof may be mixed and used. In the present disclosure, the resin of the base material layer is preferably an ABS resin or an acrylic resin, among others. This is because by using the same resin as the resin molded product described later, it is possible to improve the adhesion to the resin molded product in the case of a decorated resin molded product.

Further, the base material layer may be a single layer film of resin, or a laminate of resin layers containing the same or different resins (multilayer film).

The base material layer in the present disclosure may be subjected to a physical or chemical surface treatment such as an oxidation method or a roughening method on one side or both sides, if necessary. This is because the adhesion with the surface protective layer, the decorative layer, the primer layer, etc. can be improved. Examples of the oxidation method performed as the surface treatment of the base material layer include a corona discharge treatment, a plasma treatment, a chromium oxidation treatment, a flame treatment, a hot air treatment, an ozone ultraviolet treatment method, and the like. Further, examples of the roughening method performed as the surface treatment of the base material layer include a sandblast method and a solvent treatment method. Further, the base material layer may be colored with a coloring agent or the like, coated for adjusting the color, or formed with a pattern for imparting designability.

The thickness of the base material layer is appropriately set depending on, for example, the application of the decorative sheet, the molding method for integrating with the resin molded product, and the like. The thickness of the base material layer is usually about 25 to 1000 μm, preferably about 50 to 700 μm from the viewpoint of three-dimensional moldability and shape retention. Specifically, when the decorative sheet of the present disclosure is subjected to the insert molding method, it is usually about 50 to 1000 μm, preferably about 100 to 700 μm, more preferably about 100 to 500 μm. When the sheet is subjected to the simultaneous injection-molding and decorating method, it is usually about 25 to 200 μm, preferably about 50 to 200 μm, and more preferably about 70 to 200 μm.
This is because the decorative sheet of the present disclosure can be provided with good three-dimensional moldability and shape retention.

The main surface of the substrate layer on the surface protective layer side may have a flat structure or an uneven structure. For example, in FIG. 4A, the main surface of the base material layer 1 on the surface protective layer 2 side has a flat structure. In this case, even when the decorative sheet is stretched, the rate of change in the concavo-convex structure is small, so that the antiglare property can be maintained high. When another layer such as a decorative layer is provided between the base material layer and the surface protection layer, the main surface of the other layer preferably has a flat structure. In addition, in FIG. 4A, the main surface of the surface protective layer 2 on the base material layer 1 side has a flat structure. On the other hand, in FIG. 4B, the main surface of the base material layer 1 on the surface protective layer 2 side has an uneven structure. As shown in FIG. 4B, the concave-convex structure of the base material layer 1 and the concave-convex structure of the surface protective layer 2 may have the same period. The height difference of the unevenness in the base material layer 1 may be larger than the height difference of the unevenness in the surface protective layer 2. In addition, in FIG. 4B, the main surface of the surface protective layer 2 on the base material layer 1 side does not have a flat structure.

3. Laminated Structure of Decorative Sheet The decorative sheet of the present disclosure has at least a base material layer and a surface protection layer. In addition, the decorative sheet of the present disclosure may include a primer layer, if necessary, for the purpose of enhancing the adhesion between adjacent layers. In addition, a decorative layer may be provided, if necessary, for the purpose of imparting decorative properties to the decorative sheet. Further, for the purpose of imparting durability such as ultraviolet durability to the decorative sheet, a surface protective layer containing an ultraviolet absorber or the like may be separately provided, so that the surface protective layer is composed of two or more layers. Further, for the purpose of protecting the surface protective layer, a protective film layer or the like may be provided on the surface of the surface protective layer having the concavo-convex structure. Since this protective film is peeled off when it is used, a protective film having peelability is preferable. Further, in the case where the releasability is poor, in order to improve the releasability of the protective film from the surface protective layer, a release layer may be provided between the protective film and the surface protective layer. FIG. 5 shows a schematic cross-sectional view of the decorative sheet 10 of the present disclosure having a laminated structure in which the base material layer 1/decorative layer 3/surface protective layer 2 are laminated in order.

The specific laminated structure in the present disclosure is not particularly limited,
A laminated structure in which a base material layer/a decorative layer/a surface protective layer are laminated in order;
A laminated structure in which a base material layer/a primer layer/a surface protective layer are laminated in this order;
A laminated structure in which a base material layer/a decorative layer/a primer layer/a surface protective layer are laminated in this order;
A laminated structure in which a base material layer/surface protective layer/protective film layer are laminated in order;
A laminated structure in which a base material layer/surface protective layer/release layer/protective film layer are laminated in this order;
A laminated structure in which a base material layer/a decorative layer/a surface protective layer/a protective film layer are laminated in this order;
A laminated structure in which a base material layer/a decorative layer/a primer layer/a surface protective layer/a protective film layer are laminated in order;
A laminated structure in which a base material layer/decorative layer/primer layer/surface protective layer/release layer/protective film layer are laminated in this order;
Examples thereof include a laminated structure in which a base material layer/decorative layer/primer layer/first surface protective layer/second surface protective layer/protective film layer are laminated in order.

The resin forming the primer layer is not particularly limited, but examples thereof include urethane resin, acrylic resin, (meth)acrylic-urethane copolymer resin, polyester resin, butyral resin, and the like. Among these resins, urethane resins, acrylic resins, and (meth)acrylic-urethane copolymer resins are preferable. These resins may be used alone or in combination of two or more.

The thickness of the primer layer is not particularly limited, but is, for example, about 0.5 to 20 μm, preferably about 1 to 5 μm. By satisfying such a thickness of the primer layer, it is possible to further enhance the weather resistance of the decorative sheet and effectively suppress cracking, breakage, whitening and the like of the surface protective layer.

The decorative layer is a layer provided as needed for the purpose of imparting decorative properties to the resin molded product. The decorative layer may form a pattern, may be solid, or may be a combination thereof. The pattern formed by the decorative layer is not particularly limited, and for example, a wood pattern, a marble pattern (for example, a travertine marble pattern), a stone pattern simulating the surface of a rock, or a cloth pattern simulating a cloth or cloth-like pattern. , Tile pasting patterns, brickwork patterns, etc., and also composite patterns such as parquet and patchwork.

The thickness of the decorative layer is not particularly limited, but is, for example, about 1 to 40 μm, preferably about 3 to 30 μm.

4. Manufacturing Method of Decorative Sheet The manufacturing method of the decorative sheet in the present disclosure is not particularly limited, but the following method may be mentioned, for example. FIG. 6 shows a manufacturing process of a decorative sheet having a laminated structure in which the base material layer 1/decorative layer 3/surface protective layer 2 illustrated in FIG. 5 are laminated in order.

A base member 4 having an uneven structure corresponding to the uneven structure is prepared (FIG. 6A).
Next, an ionizing radiation curable resin composition is prepared, and this is applied onto the uneven structure of the base member 4 and cured to form the surface protective layer 2 made of an ionizing radiation curable resin having an uneven structure (Fig. 6(B)).

Examples of the method for applying the ionizing radiation curable resin composition include known methods such as gravure coating, bar coating, roll coating, reverse roll coating and comma coating. The curing method of the ionizing radiation curable resin is appropriately selected according to the type of the ionizing radiation curable resin, and examples thereof include a method of curing the uncured resin layer by irradiating ionizing radiation such as electron beam and ultraviolet rays. Be done. When an electron beam is used as the ionizing radiation, the acceleration voltage is, for example, 70 kV or more and 300 kV or less. The irradiation dose of the electron beam is selected to be, for example, 5 kGy or more and 300 kGy or less. Further, the electron beam source is not particularly limited, and for example, various electron beam accelerators such as Cockloft-Walton type, Van de Graft type, resonance transformer type, insulating core transformer type, linear type, dynamitron type, high frequency type, etc. Can be used.

When ultraviolet rays are used as the ionizing radiation, rays containing ultraviolet rays having a wavelength of 190 nm or more and 380 nm or less are usually used. The ultraviolet source is not particularly limited, but examples thereof include a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, and a carbon arc lamp.

Next, the decorative layer 3 is formed on the surface of the surface protective layer opposite to the surface on which the uneven structure is formed (FIG. 6C). The decorative layer 3 is formed, for example, by printing various patterns using ink and a printing machine. As the ink used for the decorative layer, a mixture of a binder with a colorant such as a pigment or a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, etc. is used. The binder is not particularly limited, and examples thereof include polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated polypropylene resin, acrylic resin, Examples thereof include polyester resins, polyamide resins, butyral resins, polystyrene resins, nitrocellulose resins, and cellulose acetate resins. These resins may be used alone or in combination of two or more.

Next, the base material layer 1 is formed on the decorative layer 3 (FIG. 6C). The method of forming the base material layer 1 is not particularly limited, but a method of thermally laminating the above-mentioned resin film is preferable.

Then, the base member 4 is removed by peeling or the like to manufacture the decorative sheet 10 having a laminated structure in which the base material layer 1/decorative layer 3/surface protective layer 2 are laminated in order (FIG. 6D). ).

A-2. Decorative sheet The decorative sheet of the present disclosure is a decorative sheet that is provided with a base material layer and a surface protective layer that is disposed on one main surface side of the base material layer and has an ionizing radiation curable resin, The surface protective layer has a concavo-convex structure on the main surface opposite to the base material layer side, the area ratio of the flat portion at the top of the concavo-convex structure is 10% or less, and the side wall portion of the concavo-convex structure is It is characterized in that the angle is 45° or more and 90° or less.

According to the present disclosure, since the concavo-convex structure has a specific structure, a decorative sheet having high antiglare property can be obtained. Further, even when the decorative sheet is stretched, the antiglare property can be maintained high. In particular, even when the resin molded product has a curved surface portion, high antiglare property can be maintained.

1. Surface Protective Layer In the surface protective layer in the present disclosure, a concavo-convex structure is provided on the surface opposite to the base material layer side. The interval of the unevenness of the uneven structure is, for example, 0.5 μm or more, and may be 1.0 μm or more. On the other hand, the interval of the unevenness of the uneven structure is, for example, 100 μm or less, and may be 75 μm or less. When the interval of the unevenness of the uneven structure is within a predetermined range, the decorative sheet can be glossy in appearance but high in antiglare property. Other matters concerning the surface protective layer are the same as the contents described in the above "A-1. Decorative sheet", and therefore the description here is omitted.

2. Base Layer, Laminated Structure of Decorative Sheet and Manufacturing Method of Decorative Sheet For the base layer, laminated structure of decorative sheet and manufacturing method of decorative sheet in the present disclosure, refer to “A-1. Decorative sheet” above. Since the contents are the same as those described in, the description here is omitted.

B-1. Decorative resin molded product In the present disclosure, a decorative resin molded product having a resin molded product having a curved surface portion and a decorative sheet disposed on at least the curved surface portion of the resin molded product, A decorative resin molded article, wherein the sheet is the above-mentioned decorative sheet, and the resin molded article and the base material layer side of the decorative sheet are arranged to face each other.

According to the present disclosure, by using the above-mentioned decorative sheet, it is possible to obtain a decorative resin molded product that looks rainbow-colored even on the curved surface portion of the resin molded product.

1. Resin molded product The resin molded product in the present disclosure has a curved surface portion having a predetermined radius of curvature. When the conventional decorative sheet is arranged on the curved surface portion of such a resin molded product, the decorative sheet stretches up to about 3 times at maximum, so that the design of the rainbow pattern cannot be seen on the curved surface portion. In the decorative sheet of the present disclosure, the surface protective layer has the above-mentioned predetermined uneven structure, so that a rainbow design can be imparted to the curved surface portion of such a resin molded product.

In the decorative resin molded product of the present disclosure, the resin molded product may be formed by selecting a resin according to the application. The molding resin forming the resin molded product may be a thermoplastic resin or a thermosetting resin.

Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, ABS resins, styrene resins, polycarbonate resins, acrylic resins, vinyl chloride resins and the like. These thermoplastic resins may be used alone or in combination of two or more.
In the present disclosure, the resin of the base material layer is preferably an ABS resin or an acrylic resin, among others. This is because it has good three-dimensional moldability.

Further, examples of the thermosetting resin include urethane resin and epoxy resin.
These thermosetting resins may be used alone or in combination of two or more.

2. Decorative Sheet The details and effects of the decorative sheet used for the decorative resin molded product of the present disclosure have been described in the above section “A-1. Decorative sheet”, and thus the description thereof is omitted here.

3. Decorative Resin Molded Product In the present disclosure, it is preferable that the longitudinal direction of the concavo-convex structure and the main stretching direction of the resin molded product are in a parallel relationship. This is because even if the decorative sheet is stretched, deterioration of the antiglare property can be suppressed. The "main stretching direction" means the direction in which the decorative sheet is stretched most. Further, “in parallel relation” means that the angle θ _α formed by the two directions is 30° or less. When two directions intersect, θ _α is the acute angle. θ _α may be 15° or less, 10° or less, 5° or less, and 0° (parallel).

In the present disclosure, it is preferable that the longitudinal direction of the concavo-convex structure and the light incident direction are arranged so as to be orthogonal to each other in a plan view. By arranging the decorative resin molded product in this manner, high antiglare property can be exhibited. Specifically, as shown in FIG. 7(A), it is preferable that the decorative resin molded product 100 is arranged such that the longitudinal direction of the concavo-convex structure and the light incident direction are orthogonal to each other. By arranging the decorative resin molded product 100 in this way, as shown in FIG. 7B, most of the incident light L ₁ is reflected as reflected light L ₂ and high antiglare property is exhibited. You can Further, “in an orthogonal relationship” means that the angle θ _β formed by the two directions is 75° or more and 90° or less. θ _β is an acute angle. θ _β may be 80° or more and may be 85° or less. On the other hand, θ _β may be 90° (orthogonal) or may be less than 90°. Although FIG. 7B shows the flat surface portion of the resin molded product 20, it is preferable that the resin molded product 20 has a curved surface portion. Further, in FIG. 7B, the cross-sectional shape of the concavo-convex structure in the surface protective layer 2 is a triangle in which the lengths of the two hypotenuses are the same, but as shown in FIG. May have different triangles. In that case, it is preferable that the long hypotenuse is arranged on the light incident side.

4. Manufacturing Method of Decorative Resin Molded Product The decorative resin molded product of the present disclosure can be manufactured using an insert molding method or an injection molding simultaneous decoration method.

Here, the insert molding method is a method of arranging a decorative sheet on the surface of a resin molded product, and is a method of simultaneously forming an article and arranging the decorative sheet. In the insert forming method, a forming step of forming a decorative sheet into an article surface shape in advance (offline preforming), arranging the formed decorative sheet in an injection molding die, and then closing the injection molding die An injection step of injecting a resin composition in a state into the injection molding die, and by molding the injected resin composition, an article is molded, and a decorative sheet is arranged on the surface of the article. And at least.

In the molding step, the decorative sheet may be heated and molded. The heating temperature of the decorative sheet in the molding step can be appropriately selected according to the thickness, layer configuration, material, etc. of the decorative sheet and is not particularly limited, but is, for example, 100° C. or higher and 250° C. or lower. The temperature may be 130° C. or higher and 200° C. or lower.
The temperature of the fluid resin in the injection step may be, for example, 180°C or higher and 320°C or lower, preferably 220°C or higher and 280°C or lower.

The injection molding simultaneous decorating method is a method of arranging a decorative sheet on the surface of a resin molded product, and is a method of simultaneously molding an article and arranging the decorative sheet. The injection-molding simultaneous decoration method is a method also called an in-mold molding method. In the injection-molding simultaneous decoration method, for example, a pre-forming step of pre-forming (in-line pre-forming) a decorative sheet using a combined female die having the functions of a female die and a vacuum forming die in the injection die; An injection step of closing the injection molding die in which the molded decorative sheet is arranged and injecting a resin composition in a fluid state into the injection molding die, and solidifying the injected resin composition to obtain an article And a solidifying step of disposing a decorative sheet on the surface of the article.

5. Uses The decorative resin molded article of the present disclosure includes, for example, interior materials or exterior materials for vehicles such as automobiles; fittings such as window frames and door frames; interior materials for buildings such as walls, floors, and ceilings; television receivers, It can be used as a housing for home appliances such as air conditioners; a container.

B-2. Decorative resin molded article In the present disclosure, a decorative resin molded article having a resin molded article and a decorative sheet arranged on one main surface side of the resin molded article, wherein the decorative sheet is A decorative resin molded product, characterized in that the resin molded product and the base material layer side of the decorative sheet are arranged so as to face each other.

According to the present disclosure, a decorative resin molded article having high antiglare properties can be obtained by using the above-mentioned decorative sheet.

1. Resin molded product The resin molded product according to the present disclosure usually has at least one of a flat surface portion and a curved surface portion.
Further, the resin molded product preferably has at least a curved surface portion. When the conventional decorative sheet is stretched and arranged on such a resin molded product, the antiglare property may be lowered. With the decorative sheet of the present disclosure, since the surface protective layer has the above-mentioned predetermined uneven structure, it is possible to exhibit high antiglare properties even when stretched. In particular, high antiglare properties can be exhibited even in the curved surface portion of the resin molded product.

The details of the resin molded product used as the decorative resin molded product of the present disclosure are the same as the contents described in the above-mentioned section "B-1. Decorative resin molded product", and therefore the description thereof is omitted here. ..

2. Decorative sheet, decorative resin molded product, manufacturing method and application of decorative resin molded product For details of the decorative sheet used for the decorative resin molded product of the present disclosure, refer to "A-2. Decorative sheet" above. Since it has been described in the section, the description here is omitted. Further, the decorative resin molded product, the method for producing the decorative resin molded product, and the use of the decorative resin molded product of the present disclosure are the same as those described in the above section "B-1. Decorative resin molded product". The description is omitted here because it is the same.

Note that the present disclosure is not limited to the above embodiment. The above-described embodiment is an exemplification, and it has substantially the same configuration as the technical idea described in the claims of the present disclosure, and has any similar effects to the present invention. It is included in the technical scope of the disclosure.

Hereinafter, the present disclosure will be specifically described using Examples and Comparative Examples.

[Examples 1 to 5, Comparative Examples 1 to 4]
1. Manufacturing of decorative sheet A nano-imprinting method is used to form a UV-curable resin having an uneven structure on PET, and a one-dimensional lattice film (base member) having V-grooves with depths and intervals as shown in Tables 1 and 2 is formed. ) Was produced. An electron beam curable resin composition having the following composition was applied to the uneven surface side of the film by bar coating so that the thickness after curing was 10 μm. This uncured resin layer was irradiated with an electron beam having an acceleration voltage of 165 kV and a radiation dose of 50 kGy (5 Mrad) to be cured, thereby forming a surface protective layer having a concavo-convex structure. A decorative layer (thickness: 5 μm) was formed by gravure printing on the surface of the surface protective layer on the side opposite to the concavo-convex side, using an ink composition containing an acrylic resin. The pattern of the decorative layer was a wood grain pattern. Next, an ABS resin film (thickness 400 μm) was thermally laminated (120° C., 10 kgf/cm ² , 5 minutes) on the decorative layer to form a base material layer. Finally, the base member was peeled off to manufacture a decorative sheet having a laminated structure in which the base material layer/decorative layer/surface protective layer were laminated in order.

[Electron beam curable resin composition]
Trifunctional pentaerythritol acrylate (molecular weight 300): 30 parts by mass Acrylic polymer (weight average molecular weight 120,000): 70 parts by mass

2. Production of Decorative Resin Molded Product Each of the decorative sheets obtained above was heated with an infrared heater to be softened until the sheet temperature reached 160°C. Then, vacuum forming was performed using a vacuum forming die to form the inner shape of the die. The decorative sheet after vacuum forming was cooled and then released from the mold. Next, the vacuum-molded decorative sheet is put into a mold, the injection resin is injected into the cavity of the mold, the decorative sheet and the injection resin are integrally molded, and the decorative resin is taken out from the mold at the same time. A molded product was obtained.

[Evaluation]
With respect to the obtained decorative resin molded product, the surfaces of the flat surface portion and the corner portions (curved surface portion) were visually observed, and the rainbow feeling was evaluated according to the following criteria. The results are shown in Tables 1 and 2.
(Visual evaluation of rainbow feeling)
◎: Excellent rainbow feeling by visual inspection ◯: Iridescent feeling was visually observed △: It was difficult to visually recognize, but rainbow feeling was confirmed ×: No rainbow feeling was visually recognized

As is clear from Table 1 and Table 2, in the decorative resin molded product manufactured using the decorative sheet of the present disclosure, not only the flat portion but also the corner portion (curved surface portion) is provided with a visual rainbow feeling. It became a thing.

[Examples 6 to 11, Comparative Examples 5 to 7]
1. Manufacture of Decorative Sheet A UV-curing resin having an uneven structure was formed on PET by a nanoimprinting method to prepare a one-dimensional lattice film (base member) having grooves with an interval of 25 μm. The concave-convex structure of the UV curable resin has a cross-sectional shape of the concave-convex structure of the surface protective layer which is an isosceles triangle as shown in FIG. 3B or a trapezoid as shown in FIG. 3A. .. The area ratio of the flat portion and the angle of the side wall portion are shown in Tables 3 and 4. In addition, when the area ratio of the flat portion is 0.5%, the cross-sectional shape of the uneven structure of the surface protective layer is a triangle, and when the area ratio is other than that, the cross-sectional shape of the uneven structure of the surface protective layer is trapezoidal. there were. The same electron beam curable resin composition as in Example 1 was applied to the uneven surface side of the above film by bar coating so that the thickness after curing was 40 μm. The uncured resin layer was irradiated with an electron beam having an acceleration voltage of 165 kV and a radiation dose of 50 kGy (5 Mrad) to be cured, thereby forming a surface protective layer having an uneven structure. A decorative layer (thickness 5 μm) was formed by gravure printing on the surface of the surface protective layer opposite to the concavo-convex side, using an ink composition containing an acrylic resin. The pattern of the decorative layer was a wood grain pattern. Then, an ABS resin film (thickness 400 μm) was thermally laminated (120° C., 10 kgf/cm ² , 5 minutes) on the decorative layer to form a base material layer. Finally, the base member was peeled off to manufacture a decorative sheet having a laminated structure in which the base material layer/decoration layer/surface protection layer were laminated in order. A decorative resin molded product was obtained in the same manner as in Example 1 except that the obtained decorative sheet was used.

[Evaluation]
The specular reflection light of a fluorescent lamp with an incident angle of 45° and an incident angle of 50° with respect to the flat surface portion of the obtained decorative resin molded product was visually observed, and the glare was evaluated according to the following criteria. The results are shown in Tables 3 and 4.
(Evaluation of glare by visual observation of 10 people)
◎: 1 person or less who felt dazzling ○: 2 or 3 persons who felt dazzling △: 4 or 5 persons who felt dazzling ×: 6 persons who felt dazzling More than 10 people

As is clear from Tables 3 and 4, the area ratio of the flat portion and the angle of the side wall portion are within the predetermined ranges, so that the decorative sheet has high antiglare properties even when the decorative sheet is stretched. A resin molded product was obtained. Further, also in the corner portion (curved surface portion) of the decorative resin molded product, a decorative resin molded product having a high antiglare property was obtained as in the flat surface portion.

[Example 12]
A UV curable resin having an uneven structure was formed on PET by a nanoimprint method to prepare a one-dimensional lattice film (base member) having a V groove with an interval of 25 μm and an apex angle of 50°.
An ABS resin film (thickness 400 μm) is thermally laminated (120° C., 10 kgf/cm ² , 5 minutes) on the uneven surface side of the film, and the base member is peeled off to form a substrate layer having an uneven structure on the surface. Formed. On the concavo-convex structure of the base material layer, a decorative layer (thickness 5 μm) was formed by gravure printing using an ink composition containing an acrylic resin. The pattern of the decorative layer was a wood grain pattern. Further, the same electron beam curable resin composition as in Example 1 was applied onto the surface of the decorative layer by bar coating so that the thickness after curing was 10 μm. This uncured resin layer was irradiated with an electron beam having an accelerating voltage of 165 kV and a radiation dose of 50 kGy (5 Mrad) to be cured to form a surface protective layer. Thereby, a decorative sheet was manufactured. As shown in FIG. 8, the surface protective layer 2 and the decorative layer 3 had an uneven structure on the surface so as to follow the uneven structure of the ABS resin film as the base material layer 1. A decorative resin molded product was obtained in the same manner as in Example 1 except that the obtained decorative sheet was used.

[Evaluation]
The specular reflection light of a fluorescent lamp having an incident angle of 45° and an incident angle of 50° with respect to the flat surface portion of the obtained decorative resin molded product was visually observed, and the glare was evaluated according to the same criteria as in Example 6. The results of Example 6 and Example 12 are shown in Table 5.

As is clear from Table 5, even when the decorative sheet is stretched, higher antiglare property can be obtained by flattening the surface of the base material on the surface protective layer side as in Example 6. Was obtained.

1... Base material layer 2... Surface protection layer 3... Decorative layer 4... Base member 10... Decorative sheet

Claims (6)

A decorative sheet comprising a base material layer and a main surface side of the base material layer, the surface protection layer having an ionizing radiation curable resin,
The surface protective layer has a concavo-convex structure on the main surface opposite to the base material layer side,
The decorative sheet, wherein the unevenness of the uneven structure has an interval of 0.5 μm or more and 7.5 μm or less, and the unevenness of the unevenness of the uneven structure is 0.2 μm or more. The area ratio of the flat portion at the top of the uneven structure is 10% or less,
The decorative sheet according to claim 1, wherein an angle of a side wall portion of the uneven structure is 45° or more and 90° or less. The decorative sheet according to claim 1 or 2, wherein the cross-sectional shape of the concavo-convex structure is a triangle whose two hypotenuses have the same length. The decorative sheet according to claim 1 or 2, wherein the cross-sectional shape of the concavo-convex structure is a triangle whose two hypotenuses have different lengths. The decorative sheet according to claim 1 or 2, wherein the uneven structure has a trapezoidal cross-sectional shape. The decorative sheet according to any one of claims 1 to 5, wherein a main surface of the base material layer on the surface protective layer side has a flat structure.

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