JP2000303034A - Adhesive sheet - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide excellent appearance weather resistance, flexibility, workability to a three-dimensional curved surface, suitable film tearing property required for a marking film, and also good cutting performance when cutting with a cutting machine or the like. Provided is a pressure-sensitive adhesive sheet which secures cutting properties and good debris removal properties over time, and can be treated with a simple incineration facility after use. The pressure-sensitive adhesive sheet has a colored base material layer, a pressure-sensitive adhesive layer, and release paper laminated in this order. A contraction strain is given to the colored base material layer with respect to the release paper. When half-cut from the colored base material layer to the depth reaching the release paper, the interval between adjacent cut pieces of the cut pressure-sensitive adhesive layer is 0.03 to 0.10 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive sheet used for decorative marking films such as outdoor and indoor advertisement stickers and display stickers.

[0002]

2. Description of the Related Art In general, a marking film is formed by using a polyvinyl chloride resin film as a base layer and coloring the base layer by kneading a pigment according to the purpose, or by printing on one side of the base layer. Apply a coating to form a colored coating layer, apply an appropriate pressure-sensitive and / or heat-sensitive adhesive to the opposite surface according to the application to form a pressure-sensitive adhesive layer, and then release the pressure-sensitive adhesive layer to protect the pressure-sensitive adhesive layer. In use, the release paper is peeled off and the pressure-sensitive adhesive layer is adhered to a predetermined location. Marking films are often used outdoors, and are used for signboards, advertising towers, shutters, show windows, etc .; advertising stickers used for vehicles such as automobiles and motorcycles, and decorative stickers used for ships such as motor boats; It is used for applications such as display signs used for traffic signs, road signs, and information boards. For this reason, it is necessary that the marking film has weather resistance and has appropriate flexibility for attaching to a cubic curved surface.

[0003] Marking films are often cut into various character designs and used, and after cutting, unnecessary portions are scraped, so that good cutability and good scrap removal are required. .

Conventionally, in order to improve the cutability of a marking film, the dynamic peel resistance from a peelable support is 8 to 40 g / inch at a pulling speed of 0.3 m / min and 25 to 40 g / inch at a pulling speed of 9 m / min. A method of 100 g / inch has been proposed (see Japanese Patent No. 2691994).
However, in this method, the cut property is defined by a dynamic peeling resistance that changes with time. Therefore, in an actual product, quality stability is poor, and in actual use, debris removal property is insufficient. .

[0005] Further, since the conventional marking film uses a polyvinyl chloride resin film as a base material layer, there is a possibility that hydrogen chloride gas or dioxin may be generated at the time of incineration disposal. Cannot be processed,
Further, there is a problem that the durability of the incineration equipment is reduced. Therefore, recently, there has been an increasing demand for a low environmental load type marking film that can be processed by a simple incineration facility. For example, a marking film described in JP-A-8-157780 uses a polyolefin-based resin film as a base material layer and enables easy incineration disposal.

[0006] However, the above publication does not disclose any polyolefin resin film for the base material layer. The marking film made by using a commercially available polyolefin resin film as the base material layer is more flexible and workable on a three-dimensional curved surface than the marking film using a polyvinyl chloride resin film as the base material layer. However, it cannot be used for actual use.

[0007]

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a marking film which is required to have excellent weather resistance, flexibility, workability on a cubic curved surface, and excellent film tearability. In addition, it is an object of the present invention to provide a pressure-sensitive adhesive sheet which ensures good cutability at the time of cutting with a cutting machine or the like and good debris removal property over time, and which can be treated with a simple incineration facility after use.

[0008]

Means for Solving the Problems The present inventor has studied the above problems, and as a result, has found that in a pressure-sensitive adhesive sheet in which a colored base material layer, a pressure-sensitive adhesive layer and a release paper are laminated in this order,
By imparting shrinkage strain to the colored base material layer on the release paper, when the pressure-sensitive adhesive sheet is half-cut using a cutting machine or the like, cutability is good due to shrinkage strain of the base material layer, and cut. After that, the interval between adjacent cut pieces of the pressure-sensitive adhesive layer was widened, and as a result, it was found that the debris-removing property was good over time, and the product was completed.

That is, the present invention relates to an adhesive sheet in which a colored base material layer, an adhesive layer and a release paper are laminated in this order, wherein a shrinkage strain is imparted to the colored base material layer with respect to the release paper. When the half cut to a depth reaching the release paper from the colored base material layer, the interval between adjacent cut pieces of the cut adhesive layer is 0.03 to 0.10 mm. It is.

In the pressure-sensitive adhesive sheet according to the present invention, when the distance between adjacent cut pieces of the cut pressure-sensitive adhesive layer is smaller than 0.03 mm, the property of removing debris with time is not good, and the pressure-sensitive adhesive layer has a pressure-sensitive adhesive property of 0.10.
If it exceeds mm, the curl becomes large, which is not preferable.

The method of imparting shrinkage strain to the colored base material layer may be a method of shrinking the base material layer side or a method of elongating the release paper side. There is no restriction as long as the method is applied. Specifically, a method of laminating the colored base material layer, the pressure-sensitive adhesive layer and the release paper in this order and then heating the whole by passing through a drying oven, or the opposite surface of the colored base material layer after the lamination to the pressure-sensitive adhesive layer surface A method of heating the pressure-sensitive adhesive sheet at the time of providing the colored coating film layer is appropriately adopted.

The colored base material layer preferably comprises a polyolefin-based resin as a main component, or comprises a support layer containing a polyolefin-based resin as a main component and a colored coating layer. The colored coating layer is formed of 100 parts by weight of at least one resin component selected from the group consisting of an acrylic resin, a urethane-based resin, a polyester-based resin, and a fluororesin, and 5-200 parts by weight of a pigment. There may be.

Hereinafter, the pressure-sensitive adhesive sheet according to the present invention will be described in detail.

As the film for the colored base material layer, various general films can be used. Among them, it is preferable to use a film made of a polyolefin resin that can be easily incinerated.

Preferred examples of the polyolefin resin for the colored base material layer have a weight average molecular weight (Mw) of 80,000 to 5
A polypropylene-based resin (hereinafter abbreviated as PP-based resin) in the range of 00000, wherein the PP-based resin has a resin elution amount of 0 ° C. or more and 10 ° C. or less according to the cross fractionation method of the total PP-based resin amount. 45 to 80% by weight, and the resin elution amount at more than 10 ° C. and 70 ° C. or less is 5 to 3% of the total amount of the PP resin.
5% by weight, and the resin elution amount between 70 ° C. and 95 ° C. or less is 1-30% by weight of the total PP resin amount, and the resin elution amount between 95 ° C. and 125 ° C. or less is all PP resin Quantity 3
It has a composition within the range of about 35% by weight.
Titanium oxide may be further added to the above composition in an amount of 50 to 300 parts by weight based on 100 parts by weight of the PP resin.

This PP-based resin film can form a colored base material layer that is very flexible and concealable and has an appropriate tearing property, and the tertiary curved surface workability and tearability are significantly improved. Particularly preferred. The colored base material layer may be a single layer or a multilayer.

Preferred examples of the PP resin for the colored base material layer are a propylene-ethylene copolymer or a propylene-α-olefin copolymer. This resin can be produced by the following method. First, as a first step, polymerization is carried out using a propylene monomer and, if necessary, an α-olefin monomer other than propylene in the presence of a titanium compound catalyst and an aluminum compound catalyst to obtain a first PP-based polyolefin. Then, as a second step, in the presence of the titanium compound catalyst, the titanium-containing PP-based polyolefin produced in the first step and propylene, ethylene or other α-olefin are copolymerized to form a second PP-based polyolefin. obtain. Hereinafter, a multi-stage copolymerization reaction can be performed according to the purpose in the same manner. Preferred examples of the first PP-based polyolefin produced in the first step are a propylene homopolymer, a propylene-ethylene copolymer, or a propylene-α-olefin copolymer.

Preferred as the material resin for the colored base material layer are those having a weight average molecular weight (Mw) of 80,000 to 500,
000, more preferably 200,000 to 400,000
It is a PP resin in the range of 0. The weight average molecular weight of the PP resin is, for example, high temperature GPC (15
0 CV). If the weight average molecular weight of the PP resin is less than 80,000, the film strength is insufficient,
If it exceeds 500,000, sufficient flexibility may not be obtained.

In the present invention, a cross fractionation chromatography method adopted as an index for specifying a PP resin is as follows.

First, the PP resin is heated at 140 ° C. or PP.
The resin is dissolved in o-dichlorobenzene at a temperature at which the resin completely dissolves, and then the solution is cooled at a constant rate to form a thin polymer layer on the surface of the previously prepared inert carrier. At this time, the PP resin component is in the order of higher crystallinity,
And it is produced as a polymer layer in the descending order of the molecular weight.
Next, the temperature is increased continuously or stepwise, the concentration of the components eluted sequentially is detected, and the component distribution (crystallinity distribution) is measured. This is based on temperature rise elution fractionation (Temperature Risin
g Elution Fractionation (TREF). At the same time, the eluted components are separated by high-temperature GPC (Size E
Analysis by xclusion Chromatograph (SEC) to determine molecular weight and molecular weight distribution. In the present invention, a cross-separation chromatograph (CFC-T150A manufactured by Mitsubishi Chemical Corporation) having both the above-mentioned temperature-rise elution fractionation part and the high-temperature type GPC part as a system is used.

In the PP-based resin for the colored base material layer, the amount of the resin eluted at 0 ° C. or more and 10 ° C. or less by the above-mentioned cloth separation method is 45 to 80% by weight of the total PP-based resin. If the elution amount is less than 45% by weight, the obtained film lacks flexibility, and if it exceeds 80% by weight, sufficient strength as a film cannot be obtained.

The elution amount of the resin at a temperature exceeding 10 ° C. and 70 ° C. or less is 5 to 35% by weight based on the total amount of the PP resin. If the elution amount is less than 5% by weight, the obtained film lacks flexibility and
If it exceeds 5% by weight, the film is inferior in deformation recovery.

The amount of resin eluted above 70 ° C. and 95 ° C. is 1 to 30% by weight of the total PP resin. This elution amount is 1
If the amount is less than 10% by weight, the obtained film is inferior in deformation recovery,
If it exceeds 30% by weight, the strength as a film cannot be obtained.

Finally, when the temperature exceeds 95 ° C.
The resin elution amount at 25 ° C. or less is 3 to 35 times the total PP resin amount.
% By weight. If the elution amount is less than 3% by weight, sufficient strength as a film cannot be obtained, and if it exceeds 35% by weight, the film is inferior in flexibility.

In the PP resin constituting the colored base material layer, the elution amount in each temperature range by the cross fractionation method within the above range means that the obtained film has physical properties such as elastic modulus, strength, and ductility. It is very important in controlling.

In general PP resin, stress-strain (S-
S) According to the curve, the force rises sharply at the time of low elongation, yields when the elongation is 20 to 30%, and the stress hardly increases until about 100% elongation. That is, S-
In the S-curve, the stress with respect to the strain is almost constant. When such a resin is applied to a marking film, for example, if the film is strongly pulled at the time of forming a curved surface, the film may be extended completely. However, a flexible film can be obtained by applying the PP resin as described above to the marking film.

Generally, in the case of a polymer blend, one method is to increase the molecular weight of the rubber component to be blended in order to improve flexibility and stretchability. P used in the present invention
In the case of a P-based resin, the rubber component is a component (α-olefin-propylene copolymer, ethylene-propylene copolymer) formed by the reaction after the second step, and these components have a high molecular weight. Therefore, the melt viscosity is high. This rubber component can be finely dispersed in the PP resin by using the above-mentioned multi-stage polymerization method. However, in a blending method using an ordinary extruder or the like, when a rubber component having such a high molecular weight is used, a resin having a finely dispersed morphology such as a PP resin used in the present invention is used because the melt viscosity is high. Cannot be created. Further, in a resin such as a PP-based block copolymer obtained by a conventional reaction, the block components such as ethylene and α-olefin to be copolymerized are in a production process of about PP, which is a main component, due to the production process. The limit is about 50% by weight, usually up to 30% by weight. For this reason, it has been very difficult to realize flexibility such as plasticized polyvinyl chloride resin in the PP resin.

However, if the above-described multi-stage polymerization method is used, the copolymer component can be contained in an amount of about 80 to 95% by weight, and has the same physical properties as the plasticized polyvinyl chloride resin. A PP-based resin is obtained.

Examples of such a flexible PP resin include "PER" manufactured by Tokuyama Corporation and "Cataroy" manufactured by Montell JPO. These are all used in the present invention. In addition, low-density polyethylene, medium- or high-density polyethylene, or polypropylene mixed with EPR or a styrene-based elastomer can also be used.

As the resin for the colored coating film layer of the present invention, an acrylic resin, a urethane resin, a polyester resin or a fluorine resin having good weather resistance can be used. Acrylic resin paints are particularly preferred. The pigment is preferably blended in an amount of 5 to 200 parts by weight with respect to 100 parts by weight of each coating resin.

As the pigment to be mixed with the resin, generally used organic pigments having good weather resistance are suitable.

In the present invention, in order to color the base material layer in various colors, the pigment is mixed with the base material resin by, for example, making a masterbatch which is widely used as a technique for improving the dispersibility of the pigment in the resin. It is preferable to keep it.

In order to impart weather resistance to the polyolefin-based substrate layer, a hindered amine compound which is conventionally compounded in a polyolefin-based resin may be added. Specifically, the following can be exemplified.

1) 2,2,4,4-tetramethylpiperidyl-4-benzoate 2) bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate 3) tris (2,2,6) 6-tetramethyl-4-piperidyl) phosphite 4) 1,3,8-triaza-7,7,9,9-tetramethyl-3-n-octylspiro [4,5] decane-
2,4-dione 5) 1,2,3,4-tetra (4-carbonyloxy-2,2,6,6-tetramethylpiperidyl) butane 6) 1,3,8-triaza-7,7,9 7,9-tetramethyl-2,4-dioxospiro [4,5] decane 7) tri (4-acetoxy-2,2,6,6-tetramethylpiperidyl) -amine 8) 4-acetoxy-2,2,6 9,6-tetramethylpiperidyl 9) 4-stearoyloxy-2,2,6,6-tetramethylpiperidyl 10) 4-benzyloxy-2,2,6,6-tetramethylpiperidyl 11) 4-phenylcarbamoyloxy- 2,2
6,6-tetramethylpiperidyl

The resin for the substrate layer of the present invention may further contain other general-purpose additives (antistatic agent, antiblocking agent, antioxidant, ultraviolet absorber, inorganic filler, organic filler).
Is also preferred.

The thickness of the base material layer is 20 to 150 in total.
μm, preferably 40 to 60 μm. When the thickness is less than 20 μm, the film itself is too soft, which makes the construction difficult and insufficient strength. When the thickness exceeds 150 μm, the film becomes harder,
Followability to an adherend such as a cubic curved surface may be poor.

The film for the base material layer is prepared by mixing the above-mentioned additives into the resin for the base material layer, and then forming the compound by a conventionally used T-die method, inflation method or the like. Can be obtained by Since the obtained substrate layer film generally has a low surface tension, it is desirable to improve the adhesion of the colored coating layer and the pressure-sensitive adhesive layer by a surface modification treatment such as a corona treatment.

The colored coating layer is formed by applying a resin coating with a thickness of 5 to 40 μm, preferably 10 to 35 μm by a gravure coater, comma coater, reverse coater, knife coater, spray gun, screen printing or the like. .

If the thickness of the colored coating film layer is small, the effect of preventing the see-through of the underlayer becomes small, and it becomes difficult to obtain a desired color toning and a uniform appearance. In addition, the total thickness of the coating film is 40
If it exceeds μm, the ability to follow an adherend such as a cubic curved surface of the sheet will be poor.

The pressure-sensitive adhesive used for the pressure-sensitive adhesive layer may be an acrylic resin-based or rubber-based pressure-sensitive adhesive. However, since the marking film is assumed to be used outdoors, an acrylic-based material having high weather resistance is used. Good. As the (meth) acrylate monomer used as a main component of the acrylic pressure-sensitive adhesive layer, a (meth) acrylate ester of an alcohol having an alkyl group having 1 to 12 carbon atoms, preferably an alkyl group having 4 to 12 carbon atoms is used. Have (meta)
Acrylic acid ester is used. Specifically, (meth)
N-butyl acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, (meth)
Examples thereof include n-octyl acrylate, isononyl (meth) acrylate, lauryl (meth) acrylate, and the like. These can be used alone or in combination. From the viewpoint of the balance between tackiness and cohesiveness, etc., a homopolymer usually contains a (meth) acrylate ester having a glass transition temperature (Tg) of -50 ° C. or lower as a main component, methyl (meth) acrylate, and ethyl (meth) acrylate. It is preferable to use a (meth) acrylic acid ester of a lower alcohol such as the above.

Further, in addition to these vinyl monomers, monomers copolymerizable with them may be copolymerized.
Examples of such a copolymerizable monomer include carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, fumaric acid, and itaconic acid or anhydrides thereof, 2-hydroxyethyl (meth) acrylate, and 4-hydroxybutyl acrylate. And hydroxyl-containing monomers such as polyoxyethylene (meth) acrylate, polyoxypropylene (meth) acrylate, and caprolactone-modified (meth) acrylate.

The pressure-sensitive adhesive may be a solvent-type acrylic pressure-sensitive adhesive polymerized in a solvent, an emulsion-type pressure-sensitive adhesive polymerized in water, or a bulk polymerizable pressure-sensitive adhesive obtained by irradiating a monomer mixture with ultraviolet rays. You may. The thickness of the pressure-sensitive adhesive layer is preferably from 20 to 50 μm. The adhesive sheet for the marking film is generally formed by applying a pressure-sensitive adhesive to a release paper by a quantitative coating method such as a reverse coating method and drying by heating, and then a colored coating layer is formed on one side of the base material layer. If it is, it is manufactured by laminating an adhesive layer on the opposite surface.

The release paper of the pressure-sensitive adhesive sheet of the present invention is not particularly limited as long as it imparts shrinkage strain to the colored base material layer. For example, high-quality paper laminated with polyethylene on both sides and coated with silicone And those obtained by applying silicone to a PET substrate.

[0044]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist.

(Manufacture of Marking Film) <Example 1> A homo PP resin having a melt index (3.9 g / 10 min) was used as the resin for both outer layers, and a cloth having a weight average molecular weight of 200,000 and a cloth was used as the material for the intermediate layer. 69% by weight when the elution amount at each temperature by the fractionation method is 0 ° C or less,
11% by weight above 10 ° C and below 70 ° C, 9% above 70 ° C
2% by weight at 5 ° C or less, 18% at 95 ° C or more and 125 ° C or less
% Of a PP resin (manufactured by Tokuyama Co., Ltd.) and 8 parts by weight of a blue pigment, Sinian Blue, with respect to 100 parts by weight of the intermediate layer resin. To a thickness of 50 μm (both outer layer thicknesses: 8 μm each, intermediate layer thickness: 34 μm), and a double-sided corona treatment (42 dyne / cm) was performed in-line. The obtained film was used as a base material layer, and an adhesive layer on one side thereof,
Furthermore, after providing a release paper thereon, a paint is applied to the surface opposite to the adhesive layer surface, and a colored coating film layer is formed by heating and drying,
A marking film was obtained.

The colored coating layer is prepared by adding 6.5 parts of a curing agent "Coronate 2094" (manufactured by Nippon Urethane Co., Ltd.) to 100 parts by weight of a urethane resin paint "Planit U # 500" (manufactured by Dainippon Paint Co., Ltd.). Further, a composite pigment mainly composed of a cyanine blue pigment was added to obtain a blue-colored coating composition, which was applied with a spray gun coater to a thickness of 20 μm to form a coating composition.

The above composite pigments (cyanine blue, quinacridone red, polyazo yellow, cyanine green, etc.)
Is manufactured by Dainichi Seika.

The release paper is obtained by coating a 75 μm-thick PET surface with an addition-type silicone having a dry thickness of 0.5 μm.

The pressure-sensitive adhesive layer was formed by applying a two-component crosslinkable acrylic pressure-sensitive adhesive to a silicone-coated release paper with a comma coater so as to have a dry thickness of 40 μm. This was laminated on one side of the substrate layer.

<Example 2> In Example 1, a paint was not applied to the surface of the base material layer opposite to the surface of the pressure-sensitive adhesive layer.
A laminate comprising an adhesive layer and release paper was obtained, and a marking sheet was obtained in the same manner as in Example 1 except that the laminate was heated.

Example 3 A homo PP resin having a melt index (3.9 g / 10 min) was used as the resin for both outer layers, and a weight average molecular weight of 25 for the intermediate layer was used as the material for the intermediate layer.
000, the elution amount at each temperature by the cross fractionation method is 0
48% by weight at 10 ° C. or more and 10 ° C. or less, 19% by weight at 10 ° C. or more and 70 ° C. or less, 5% by weight at 70 ° C. or more and 95 ° C. or less,
Using a PP resin (manufactured by Montell JPO) having a weight ratio of more than 95 ° C. and less than 125 ° C. and 28% by weight, these are multi-layer extruded
The film was formed by a die machine so as to have a thickness of 50 μm, and subjected to in-line corona treatment (42 dyne / cm) in-line. This intermediate layer resin was mixed with 100 parts by weight of titanium oxide based on 100 parts by weight of the resin to obtain a white film.

As the release paper, both sides of a high-quality paper are subjected to clay treatment, and the surface thereof is coated with an addition type silicone having a dry thickness of 0.1 mm.
One coated at 5 μm was used.

The other points were the same as in Example 1 to obtain a marking film.

Example 4 A homo PP resin having a melt index (3.9 g / 10 min) was used as a resin for both outer layers, and an ethylene-vinyl acetate copolymer resin (manufactured by Mitsubishi Yuka Co., Ltd.) was used as a material for an intermediate layer. EVA20E) 50 parts by weight and ethylene-propylene rubber (manufactured by Mitsui Petrochemical Co., Ltd .: Toughmer P)
-0280) Using a blend resin by a mechanical method with 50 parts by weight, extruding these by a multilayer T-die method,
A film having a thickness of 50 μm was obtained.

The intermediate layer was mixed with 8 parts by weight of Shinian Blue.

The paint was changed to fluorine-based “Duflon” (manufactured by Nippon Paint Co., Ltd.).

In other respects, the same operation as in Example 1 was performed to obtain a marking film.

<Comparative Example 1> In Example 2, the base material layer
A marking film was obtained in the same manner as in Example 1, except that the laminate comprising the pressure-sensitive adhesive layer and the release paper was not heated.

<Comparative Example 2> Each additive was added to a polyvinyl chloride resin in the composition shown in Table 1 to prepare an organosol. This sol was applied to alkyd resin coating process paper with a comma coater and dried to obtain a film having a thickness of 60 μm. The drying condition was 180 ° C. × 7 minutes. Using the obtained film as a substrate layer, a white coating layer was provided in the same manner as in Example 1 to obtain a marking film.

<Comparative Example 3> A marking film was obtained in the same manner as in Example 1, except that the release paper used was changed to clay paper on both sides of high-quality paper.

(Performance Evaluation Test) The marking films obtained in the above Examples and Comparative Examples were evaluated for the following items. Table 2 shows the results.

<Tertiary curved surface workability> A marking film is adhered to the peak (1a) of the corrugated plate (1) shown in FIG.
Next, it was pushed into the valley (1b) with a special construction wrench. After leaving it at 23 ° C. for 3 days, the floating state of the film was evaluated according to the following criteria.

…: Moderate flexibility, no problem in application to curved adherends で な い: Inappropriate film modulus, slightly difficult to apply to curved adherends ×: Appropriate film modulus Cannot be applied to curved adherends

<Interval of pressure-sensitive adhesive layer at cutting> The marking film is half-cut from a colored base material layer to a depth reaching the release paper with a cutting machine “CG-45” manufactured by Mimaki Co., Ltd., and an adjacent cut of the cut pressure-sensitive adhesive layer is cut. The strip spacing was measured under a microscope.

<Scrap removal property> The marking film was half-cut with a cutting machine “CG-45” manufactured by Mimaki Co., Ltd. to a depth reaching the release paper from the colored base material layer. Was evaluated.

○: Very good scrap removal ×: Extremely difficult scrap removal work

<Tearability> The tearability of the marking film was evaluated by the JISK-7128 Elmendorf method. Sheet thickness is 60μ of polyvinyl chloride film thickness
m.

The optimum value is 200 to 400 (gf / 16 sheets).

<Possibility of incineration> From marking film to 5
A sample of cm × 5 cm was cut out, burned in a closed vessel, and the generated gas was collected in a cylinder, and qualitatively analyzed for hydrogen chloride and chlorine gas in the gas by gas chromatography.

…: No hydrogen chloride or hydrogen gas was detected. ×: Hydrogen chloride or hydrogen gas was detected.

<Curl Property> The curl state of the marking film was evaluated according to the following criteria.

○: no curl or slight curl ×: curl remarkable

[0073]

[Table 1]

[0074]

[Table 2]

[0075]

According to the pressure-sensitive adhesive sheet of the present invention, when the pressure-sensitive adhesive sheet is half-cut by using a cutting machine or the like, a contraction strain is imparted to the release paper to the colored base layer. The cut property is good due to the shrinkage strain of. Further, after cutting, the interval between adjacent cut pieces of the pressure-sensitive adhesive layer is widened, and as a result, the debris removability is good over time.

Further, by forming the colored base material layer from a polyolefin-based resin, the used sheet does not need to be landfilled and can be incinerated in a simple incineration facility. Such an adhesive sheet is extremely useful as a low environmental load type product.

[Brief description of the drawings]

FIG. 1 is a sectional view of a corrugated plate.

[Explanation of symbols]

 1: Corrugated board 1a: Mountain part 1b: Valley part

Claims (4)

[Claims] 1. A pressure-sensitive adhesive sheet in which a colored base material layer, a pressure-sensitive adhesive layer, and a release paper are laminated in this order, wherein a shrinkage strain is given to the colored base material layer with respect to the release paper, A pressure-sensitive adhesive sheet characterized in that, when half-cut to a depth reaching the release paper from the colored base material layer, an interval between adjacent cut pieces of the cut pressure-sensitive adhesive layer is 0.03 to 0.10 mm. 2. The pressure-sensitive adhesive sheet according to claim 1, wherein the colored base material layer is mainly composed of a polyolefin resin. 3. The pressure-sensitive adhesive sheet according to claim 1, wherein the colored base material layer comprises a support layer mainly composed of a polyolefin resin and a colored coating layer. 4. The colored coating layer comprises 100 parts by weight of at least one resin component selected from the group consisting of an acrylic resin, a urethane-based resin, a polyester-based resin and a fluororesin, and 5-200 parts by weight of a pigment. The pressure-sensitive adhesive sheet according to claim 3, wherein: