KR20230066335A - Laminate, method for producing laminate, and variable color adhesive sheet - Google Patents

Abstract

The layered product 1 includes an adherend 2, an adhesive layer 3, and an oxygen barrier layer 4 sequentially in the thickness direction. The pressure-sensitive adhesive layer 3 includes a discolored portion 10 that is discolored by an external stimulus. The oxygen transmission rate of the oxygen barrier layer 4 is 200 cm ³ /m ² ·day·atm or less.

Description

Laminate, method for producing laminate, and variable color adhesive sheet

The present invention relates to a laminate, a method for producing the laminate, and a variable color pressure-sensitive adhesive sheet. Specifically, it relates to a layered product, a method for producing the layered product, and a color-changing pressure-sensitive adhesive sheet for producing the layered product.

A display panel such as an organic EL panel has a laminated structure including a pixel panel, a cover member, and the like. In the manufacturing process of such a display panel, for example, a transparent adhesive sheet is used for bonding the elements included in the laminated structure.

In addition, as a transparent adhesive sheet disposed on the light output side (image display side) of a pixel panel in a display panel, a colored portion for imparting design, shielding, antireflection, etc. to a predetermined portion of the sheet is formed in advance. It has been proposed to use a pressure-sensitive adhesive sheet. Such an adhesive sheet is described, for example, in Patent Literature 1 below. Patent Literature 1 specifically describes an adhesive sheet having a colored portion containing a carbon black pigment.

Japanese Unexamined Patent Publication No. 2017-203810

On the other hand, there are cases in which transparency is required for the pressure-sensitive adhesive sheet from the viewpoint of inspection or the like.

In such a case, it is considered to use an adhesive sheet capable of discoloration by an external stimulus. In detail, such a pressure-sensitive adhesive sheet changes color (becomes colored) when an external stimulus is applied.

That is, in this adhesive sheet, the adhesive layer can be colored by irradiating actinic light at an arbitrary timing, thereby forming a discolored portion for imparting design, shielding, and antireflection properties to the adhesive layer. can

On the other hand, in such a pressure-sensitive adhesive sheet, a discolored portion that has been discolored by an external stimulus may be deteriorated by external light.

The present invention provides a layered product suitable for suppressing deterioration by external light of a discolored portion that has been discolored by an external stimulus, a method for manufacturing the layered product of the layered product, and a color-changing pressure-sensitive adhesive sheet for producing the layered product. .

In the present invention [1], an adherend, an adhesive layer, and an oxygen barrier layer are sequentially provided in the thickness direction, the pressure-sensitive adhesive layer has a discolored portion that is discolored by an external stimulus, and the oxygen transmission rate of the oxygen barrier layer This is a laminate that is 200 cm ³ /m ² ·day·atm or less.

In the present invention [2], the pressure-sensitive adhesive layer contains the pressure-sensitive adhesive composition and a photo-acid generator, and the pressure-sensitive adhesive composition contains the layered product described in [1] above.

In the present invention [3], the laminate according to the above [1] or [2] is provided with an active energy ray blocking layer on one side of the thickness direction of the oxygen barrier layer and/or on the other side of the thickness direction of the oxygen barrier layer. contains the body.

The present invention [4] is a first step of disposing an adhesive layer on one surface of an adherend in the thickness direction, a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus, and a thickness of the pressure-sensitive adhesive layer. In any one of the above [1] to [3], a third step of disposing an oxygen barrier layer is provided on one side of the direction, and the oxygen transmission rate of the oxygen barrier layer is 200 cm ³ /m ² ·day·atm or less. It includes the manufacturing method of the described laminated body.

In the present invention [5], a pressure-sensitive adhesive layer and an oxygen barrier layer are sequentially provided in the thickness direction, the pressure-sensitive adhesive layer can be discolored by an external stimulus, and the oxygen transmission rate of the oxygen barrier layer is 200 cm ³ /m ² · It is a variable color adhesive sheet that is day·atm or less.

This invention [6] includes the variable color adhesive sheet described in [5] above, wherein the oxygen barrier layer is disposed directly on one surface of the pressure-sensitive adhesive layer in the thickness direction.

The present invention [7] includes the variable color adhesive sheet according to the above [5] or [6] further comprising an active energy ray blocking layer.

The laminate of the present invention includes an oxygen barrier layer having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. Therefore, deterioration of the discolored portion due to external light can be suppressed.

The method for manufacturing a laminate of the present invention includes a third step of disposing an oxygen barrier layer having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less on one side of the pressure-sensitive adhesive layer in the thickness direction. Therefore, it is possible to manufacture a laminate capable of suppressing deterioration of the discolored portion due to external light.

The color-changing pressure-sensitive adhesive sheet of the present invention includes an oxygen barrier layer having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. Therefore, it is possible to manufacture a laminate capable of suppressing deterioration of the discolored portion due to external light.

1 shows a cross-sectional schematic diagram of one embodiment of a laminate of the present invention.
Fig. 2 is a schematic diagram showing one embodiment (Method 1A) of a method for manufacturing a laminate of the present invention. 2A shows a step of preparing an adherend in the first step. 2B shows a first step of disposing an adhesive layer on one side of the adherend in the thickness direction. Fig. 2C shows a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus. Fig. 2D shows a third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction.
Fig. 3 is a schematic view showing one embodiment (Method 1B) of a method for manufacturing a laminate of the present invention. Fig. 3A shows a step of preparing an adhesive layer in a third step. Fig. 3B shows a third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction. 3C shows a first step of disposing an adhesive layer on one side of the adherend in the thickness direction. Fig. 3D shows a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus.
Fig. 4 is a schematic diagram showing one embodiment (Method 1C) of a method for manufacturing a laminate of the present invention. 4A shows a step of preparing an adherend in the first step. Fig. 4B shows a first step of disposing an adhesive layer on one side of the adherend in the thickness direction. Fig. 4C shows a third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction. Fig. 4D shows a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus.
Fig. 5 is a schematic view showing one embodiment (Method 2A) of a method for manufacturing a laminate of the present invention. 5A shows the step of preparing the pressure-sensitive adhesive layer in the second step. 5B shows a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus. 5C shows a first step of disposing an adhesive layer on one side of the adherend in the thickness direction. 5D shows a third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction.
Fig. 6 is a schematic view showing one embodiment (Method 2B) of the method for manufacturing a laminate of the present invention. 6A shows the step of preparing the pressure-sensitive adhesive layer in the second step. Fig. 6B shows a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus. 6C shows a third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction. Fig. 6D shows a first step of disposing an adhesive layer on one side of the adherend in the thickness direction.
Fig. 7 is a schematic view showing one embodiment (method 2C) of the method for manufacturing a laminate of the present invention. 7A shows a step of preparing an adhesive layer in a third step. 7B shows a third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction. 7C shows a second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus. 7D shows a first step of disposing an adhesive layer on one side of the adherend in the thickness direction.
8 shows a cross-sectional schematic diagram of an embodiment of a laminate provided with an active energy ray blocking layer. Fig. 8A is a cross-sectional schematic diagram of a laminate having an active energy ray blocking layer on one side of the oxygen barrier layer in the thickness direction. Fig. 8B is a cross-sectional schematic diagram of a laminate having an active energy ray blocking layer on the other side in the thickness direction of the oxygen barrier layer. Fig. 8C is a cross-sectional schematic diagram of a laminate having an active energy ray blocking layer on one side of the barrier layer in the thickness direction and on the other side of the oxygen barrier layer in the thickness direction.
Fig. 9 shows a cross-sectional schematic diagram of an embodiment of a laminate including at least one selected from the group consisting of an active energy ray blocking layer, a base material, and an intermediate layer. Fig. 9A is a cross-sectional schematic diagram of a laminate comprising an adherend, an adhesive layer, an intermediate layer, an active energy ray blocking layer, and an oxygen barrier layer in order toward one side in the thickness direction. Fig. 9B is a cross-sectional schematic diagram of a laminate comprising an adherend, an adhesive layer, a base material, an active energy ray blocking layer, and an oxygen barrier layer in order toward one side in the thickness direction. Fig. 9C is a cross-sectional schematic diagram of a laminate comprising an adherend, an adhesive layer, an oxygen barrier layer, an active energy ray blocking layer, and a substrate in order in one direction in the thickness direction. Fig. 9D is a cross-sectional schematic diagram of a laminate comprising an adherend, an adhesive layer, an intermediate layer, a base material, an active energy ray blocking layer, and an oxygen barrier layer in order toward one side in the thickness direction. Fig. 9E is a cross-sectional schematic diagram of a laminate comprising an adherend, an adhesive layer, an intermediate layer, an active energy ray blocking layer, an oxygen barrier layer, and a substrate in order in one direction in the thickness direction.
Fig. 10 shows a cross-sectional schematic diagram of an embodiment of a laminate having a surface protective layer.
Fig. 11 shows a schematic cross-sectional view of an embodiment of the variable color pressure-sensitive adhesive sheet of the present invention.

Referring to Fig. 1, one embodiment of the laminate of the present invention will be described.

In Fig. 1, the vertical direction of the paper is the vertical direction (thickness direction). Note that the upper side of the paper is the upper side (one side in the thickness direction). Further, the lower side of the paper is the lower side (the other side in the thickness direction). In addition, the left-right direction and the depth direction of the paper plane are plane directions orthogonal to the up-down direction. Specifically, it is based on the direction arrows in each figure.

1. Laminates

The layered product 1 has a film shape (including a sheet shape) having a predetermined thickness. The layered product 1 extends in a surface direction orthogonal to the thickness direction. The layered product 1 has a flat upper surface and a flat lower surface.

As shown in Fig. 1, the layered product 1 is sequentially provided with an adherend 2, an adhesive layer 3, and an oxygen barrier layer 4 toward one side in the thickness direction. The layered product 1, more specifically, includes an adherend 2, an adhesive layer 3 disposed directly on the upper surface (on one side in the thickness direction) of the adherend 2, and an upper surface of the adhesive layer 3. An oxygen barrier layer 4 disposed directly on (on one side of the thickness direction) is provided.

The thickness of the layered product 1 is, for example, 1000 μm or less, preferably 200 μm or less.

In addition, the copper thickness is, for example, 10 μm or more, preferably 25 μm or more.

2. Adherent

As the adherend 2, an optical device, an electronic device, and its component parts are mentioned, for example.

On the other hand, in FIG. 1 , the adherend 2 has a flat plate shape, but the shape of the adherend 2 is not particularly limited. Various shapes are selected for the shape of the adherend 2 depending on the types of optical devices, electronic devices, and structural components thereof.

In addition, in the case where active energy rays are irradiated from the side of the adherend 2 in the second step of the manufacturing method of the layered product 1 described later, as the adherend 2, the adherend transmits the active energy ray. sieve is selected

Examples of adherends that transmit active energy rays include adherends that transmit ultraviolet rays.

As an adherend which transmits ultraviolet rays, alkali-free glass and PET film are mentioned, for example.

The total light transmittance (JIS K 7375-2008) of an adherend that transmits ultraviolet rays is, for example, 80% or more, preferably 85% or more.

3. Adhesive layer

The adhesive layer 3 is formed of an adhesive composition. That is, the adhesive layer 3 contains an adhesive composition.

In addition, the pressure-sensitive adhesive layer 3 is a pressure-sensitive adhesive layer having transparency (visible light transmission). The total light transmittance (JIS K 7375-2008) of the pressure-sensitive adhesive layer 3 is, for example, 80% or more, preferably 85% or more.

The adhesive composition contains a base polymer, a compound that develops color by reaction with an acid, and an acid generator.

The base polymer is an adhesive component for expressing adhesiveness in the adhesive layer 3 . The base polymer exhibits rubber elasticity in the room temperature region. Examples of the base polymer include acrylic polymers, rubber polymers, polyester polymers, urethane polymers, polyether polymers, silicone polymers, polyamide polymers, and fluoropolymers. From the viewpoint of ensuring good transparency and adhesiveness of the pressure-sensitive adhesive layer 3, an acrylic polymer is preferably used as the base polymer.

The content of the base polymer in the pressure-sensitive adhesive layer 3 is, for example, 50% by mass or more, preferably 60% by mass or more, from the viewpoint of appropriately expressing the function of the base polymer in the pressure-sensitive adhesive layer 3. , More preferably, it is 70 mass % or more.

An acrylic polymer is, for example, a polymer obtained by polymerizing a monomer component containing an alkyl (meth)acrylate in a proportion of 50% by mass or more. "(meth)acrylic acid" means acrylic acid and/or methacrylic acid.

As an alkyl (meth)acrylate, the (meth)acrylic acid alkylester which has a linear or branched C1-C20 alkyl group is mentioned, for example. Examples of such alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isopropyl (meth)acrylate, and (meth)acrylate. ) Isobutyl acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, hexyl (meth)acrylate, (meth) Heptyl acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, (meth)acrylic acid Isodecyl, (meth)acrylate undecyl, (meth)acrylate dodecyl, (meth)acrylate isotridecyl, (meth)acrylate tetradecyl, (meth)acrylate isotetradecyl, (meth)acrylate pentadecyl, (meth)acrylate hexadecyl acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, isooctadecyl (meth)acrylate, nonadecyl (meth)acrylate, and eicosyl (meth)acrylate. (meth)acrylic-acid alkyl ester may be used independently, and 2 or more types may be used together. As the (meth)acrylic acid alkyl ester, preferably, an alkyl acrylate ester having an alkyl group having 1 to 12 carbon atoms is used, and more preferably, methyl methacrylate, n-butyl acrylate, and 2-ethylhexyl acrylate are used. .

The ratio of the (meth)acrylic acid alkyl ester in the monomer component is, for example, 50% by mass or more, preferably 60% by mass, from the viewpoint of appropriately expressing basic properties such as adhesiveness in the pressure-sensitive adhesive layer 3 or more, more preferably 70% by mass or more. The ratio is, for example, 99% by mass or less.

The monomer component may also contain a copolymerizable monomer copolymerizable with (meth)acrylic acid alkyl ester. As a copolymerizable monomer, the monomer (polar group containing monomer) which has a polar group is mentioned, for example. The polar group-containing monomer is useful for modifying the acrylic polymer, such as introducing a crosslinking point into the acrylic polymer and securing cohesive force of the acrylic polymer.

Examples of the polar group-containing monomer include a hydroxyl group-containing monomer, a monomer having a nitrogen atom-containing ring, and a carboxy group-containing monomer. The copolymerizable monomer preferably includes at least one selected from the group consisting of a hydroxyl group-containing monomer, a monomer having a nitrogen atom-containing ring, and a carboxy group-containing monomer. More preferably, the copolymerizable monomer includes a carboxyl group-containing monomer.

Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, ( 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl (meth)acrylate, preferably 2-hydroxyethyl acrylate.

The ratio of the hydroxyl group-containing monomer in the monomer component is, for example, 1% by mass or more, preferably, from the viewpoint of introducing a crosslinked structure into the acrylic polymer and securing the cohesive force in the pressure-sensitive adhesive layer 3, It is 3 mass % or more, More preferably, it is 5 mass % or more. From the viewpoint of adjusting the viscosity of the polymerization reaction solution at the time of polymerizing the acrylic polymer and adjusting the polarity of the acrylic polymer (related to compatibility between various additive components in the pressure-sensitive adhesive layer 3 and the acrylic polymer), the ratio is exemplified. For example, it is 30 mass % or less, Preferably it is 20 mass % or less.

Examples of the monomer having a nitrogen atom-containing ring include N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, and N- Vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-(meth)acryloyl-2-pyrrolidone, N-(meth)acryloylphy Peridine, N-(meth)acryloylpyrrolidine, N-vinylmorpholine, N-vinyl-3-morpholinone, N-vinyl-2-caprolactam, N-vinyl-1,3-oxazine- 2-one, N-vinyl-3,5-morpholinedione, N-vinylpyrazole, N-vinylisoxazole, N-vinylthiazole, and N-vinylisothiazole, preferably may include N-vinyl-2-pyrrolidone.

The ratio of the monomer having a nitrogen atom-containing ring in the monomer component is determined from the viewpoints of securing the cohesive force in the pressure-sensitive adhesive layer 3 and securing the adhesion to the adherend in the pressure-sensitive adhesive layer 3. , for example, 1% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more.

The ratio is, for example, 30 from the viewpoint of adjusting the glass transition temperature of the acrylic polymer and adjusting the polarity of the acrylic polymer (related to compatibility between various additive components in the pressure-sensitive adhesive layer 3 and the acrylic polymer). It is mass % or less, Preferably it is 20 mass % or less.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid. As the monomer containing a carboxy group, acrylic acid is preferably used.

The ratio of the carboxy group-containing monomer in the monomer component is from the viewpoints of introducing a crosslinked structure into the acrylic polymer, securing cohesive force in the pressure-sensitive adhesive layer 3, and securing adherence to the adherend in the pressure-sensitive adhesive layer 3. In, it is, for example, 1% by mass or more, preferably 3% by mass or more. The ratio is, for example, 20% by mass or less, preferably 10% by mass or less, from the viewpoint of adjusting the glass transition temperature of the acrylic polymer and avoiding the risk of corrosion of the adherend 2 by acid.

The monomer component may contain other copolymerizable monomers. Examples of other copolymerizable monomers include acid anhydride monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, epoxy group-containing monomers, cyano group-containing monomers, amide group-containing monomers, monomers having a succinimide skeleton, maleimides, Itaconimides, alkoxy group-containing monomers, vinyl esters, vinyl ethers, and aromatic vinyl compounds.

As an acid anhydride monomer, maleic acid anhydride and itaconic acid anhydride are mentioned, for example.

Examples of the sulfonic acid group-containing monomer include styrenesulfonic acid, allylsulfonic acid, sodium vinylsulfonate, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, and sulfonic acid. propyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid.

As a phosphoric acid group containing monomer, 2-hydroxyethyl acryloyl phosphate is mentioned, for example.

As the epoxy group-containing monomer, for example, epoxy group-containing acrylates such as glycidyl (meth)acrylate and 2-ethyl glycidyl (meth)acrylate, allyl glycidyl ether, and glycidyl (meth)acrylate ether.

Examples of the cyano group-containing monomer include acrylonitrile and methacrylonitrile.

Examples of the amide group-containing monomer include N-vinylcarboxylic acid amides, N-hydroxyalkyl (meth)acrylamide, N-alkoxyalkyl (meth)acrylamide, and N,N-dimethylaminopropyl (meth)acrylamide. amides, and N-(meth)acryloylmorpholine.

Examples of N-vinylcarboxylic acid amides include (meth)acrylamide, N,N-dialkyl (meth)acrylamide, N-alkyl (meth)acrylamide, and N-vinylacetamide.

Examples of N,N-dialkyl (meth)acrylamide include N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, and N,N-dipropyl (meth)acrylamide. acrylamide, N,N-diisopropyl (meth)acrylamide, N,N-di(n-butyl) (meth)acrylamide, and N,N-di(t-butyl) (meth)acrylamide. can

Examples of N-alkyl (meth)acrylamides include N-ethyl (meth)acrylamide, N-isopropyl (meth)acrylamide, N-butyl (meth)acrylamide, and N-n-butyl (meth)acrylamide. amides.

As N-hydroxyalkyl (meth)acrylamide, for example, N-(2-hydroxyethyl) (meth)acrylamide, N-(2-hydroxypropyl) (meth)acrylamide, N-(1 -Hydroxypropyl) (meth)acrylamide, N-(3-hydroxypropyl) (meth)acrylamide, N-(2-hydroxybutyl) (meth)acrylamide, N-(3-hydroxybutyl) (meth)acrylamide, and N-(4-hydroxybutyl) (meth)acrylamide. Examples of N-alkoxyalkyl (meth)acrylamide include N-methoxymethyl (meth)acrylamide, N-methoxyethyl (meth)acrylamide, and N-butoxymethyl (meth)acrylamide. can

Examples of the monomer having a succinimide skeleton include N-(meth)acryloyloxymethylenesuccinimide, N-(meth)acryloyl-6-oxyhexamethylenesuccinimide, and N-(meth)acryloyloxymethylenesuccinimide. ) acryloyl-8-oxyhexamethylene succinimide.

As maleimides, N-cyclohexyl maleimide, N-isopropyl maleimide, N-lauryl maleimide, and N-phenyl maleimide are mentioned, for example.

Examples of itaconimides include N-methyl itaconimide, N-ethyl itaconimide, N-butyl itaconimide, N-octyl itaconimide, and N-2-ethylhexyl itaconimide. imide, N-cyclohexylitaconimide, and N-laurylitaconimide.

Examples of the alkoxy group-containing monomer include alkoxyalkyl (meth)acrylates and alkoxyalkylene glycols (meth)acrylates. Examples of alkoxyalkyl (meth)acrylates include 2-methoxyethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and propoxyethyl (meth)acrylate. , butoxyethyl (meth)acrylate, and ethoxypropyl (meth)acrylate. Examples of the alkoxyalkylene glycols (meth)acrylates include methoxyethylene glycol (meth)acrylates and methoxypolypropylene glycol (meth)acrylates.

Examples of vinyl esters include vinyl acetate and vinyl propionate.

Examples of vinyl ethers include methyl vinyl ether and ethyl vinyl ether.

As an aromatic vinyl compound, styrene, (alpha)-methylstyrene, and vinyltoluene are mentioned, for example. As olefins, ethylene, butadiene, isoprene, and isobutylene are mentioned, for example.

A copolymerizable monomer may be used independently and two or more types may be used together.

An acrylic polymer can be formed by polymerizing the above monomer components. Examples of the polymerization method include solution polymerization, bulk polymerization, and emulsion polymerization, preferably solution polymerization. In solution polymerization, a reaction solution is prepared by blending a monomer component and a polymerization initiator in a solvent, for example, and then the reaction solution is heated. Then, an acrylic polymer solution containing an acrylic polymer can be obtained by undergoing a polymerization reaction of the monomer component in the reaction solution.

As a polymerization initiator, a thermal polymerization initiator is used, for example. The usage-amount of a polymerization initiator is 0.05 mass part or more with respect to 100 mass parts of monomer components, for example. In addition, the amount of copper used is, for example, 1 part by mass or less.

As a thermal polymerization initiator, an azo type polymerization initiator and a peroxide type polymerization initiator are mentioned, for example. Examples of the azo-based polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and 2,2'-azobis(2-methyl propionic acid) dimethyl, 4,4'-azobis-4-cyanovalerian acid, azobisisovaleronitrile, 2,2'-azobis (2-amidinopropane) dihydrochloride, 2,2 '-azobis[2-(5-methyl-2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate, and 2, and 2'-azobis(N,N'-dimethyleneisobutylamidine) dihydrochloride. Examples of the peroxide-based polymerization initiator include dibenzoyl peroxide, t-butyl permaleate, and lauroyl peroxide. The thermal polymerization initiator is preferably an azo polymerization initiator, more preferably 2,2'-azobisisobutyronitrile.

The weight average molecular weight of the acrylic polymer is, for example, 100000 or more, preferably 300000 or more, more preferably 500000 or more, from the viewpoint of securing the cohesive force in the pressure-sensitive adhesive layer 3. The same weight average molecular weight is, for example, 5000000 or less, preferably 3000000 or less, more preferably 2000000 or less, still more preferably 1000000 or less, particularly preferably 800000 or less. The weight average molecular weight of the acrylic polymer is measured by a gel permeation chromatograph (GPC) and calculated in terms of polystyrene.

The glass transition temperature (Tg) of the base polymer is, for example, 0°C or lower, preferably -10°C or lower, more preferably -20°C or lower. The copper glass transition temperature is, for example, -80°C or higher.

Regarding the glass transition temperature (Tg) of the polymer, a glass transition temperature (theoretical value) obtained based on the following formula of Fox can be used. Fox's formula is a relational expression of the glass transition temperature Tg of a polymer and the glass transition temperature Tgi of the homopolymer of the monomer which comprises a polymer. In Fox's formula below, Tg represents the glass transition temperature (° C.) of a polymer, Wi represents the weight fraction of monomer i constituting the polymer, and Tgi represents the glass transition temperature of a homopolymer formed of monomer i ( °C). For the glass transition temperature of the homopolymer, literature values can be used, for example, "Polymer Handbook" (4th edition, John Wiley & Sons, Inc., 1999) and "New Polymer Library 7 Synthesis for Paints" Introduction to resins” (Kyojo Kitaoka, Polymer Publishing Society, 1995) lists the glass transition temperatures of various homopolymers. On the other hand, about the glass transition temperature of the homopolymer of a monomer, it is also possible to obtain|require by the method specifically described in Unexamined-Japanese-Patent No. 2007-51271.

Fox's equation 1/(273+Tg)=Σ[Wi/(273+Tgi)]

Examples of the compound that develops color by reaction with an acid (chromogenic compound) include leuco-based dyes, triarylmethane-based dyes, diphenylmethane-based dyes, fluorane-based dyes, spiropyran-based dyes, and rhodamine-based dyes. can be heard A color developing compound may be used independently, and 2 or more types may be used together.

As a leuco dye, for example, 2'-anilino-6'-(N-ethyl-N-isopentylamino)-3'-methylspiro[phthalide-3,9'-[9H]xanthene] , 3-dibutylamino-6-methyl-7-anilinofluoran, 3-dipropylamino-6-methyl-7-anilinofluoran, 3-diethylamino-6-methyl-7-anilinofluoran Rahn, 3-dimethylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-xylidinofluorane, and 3-(4-diethylamino-2-ethoxy phenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide.

Examples of the triarylmethane pigment include p,p',p"-tris-dimethylaminotriphenylmethane. Examples of the diphenylmethane pigment include 4,4-bis- Dimethylaminophenylbenzhydrylbenzyl ether Examples of the fluoran dye include 3-diethylamino-6-methyl-7-chlorofluorane. Examples of the rhodamine-based dye include rhodamine-B-anilinolactam.

In the pressure-sensitive adhesive layer 3, from the viewpoint of ensuring good black colorability, the color-developing compound is preferably a leuco-based dye, more preferably 2'-anilino-6'-(N-ethyl-N- Isopentylamino)-3'-methylspiro[phthalide-3,9'-[9H]xanthene] is used.

The blending amount of the color developing compound relative to 100 parts by mass of the base polymer is, for example, 0.5 parts by mass or more, preferably 1 part by mass or more. The blending amount is, for example, 10 parts by mass or less, preferably 7 parts by mass or less, and more preferably 5 parts by mass or less.

As the acid generator, a photoacid generator that generates an acid when irradiated with active energy rays is preferably used. In that case, the portion of the pressure-sensitive adhesive layer 3 that has been irradiated with active energy rays as an external stimulus can be discolored. Specifically, in the portion of the pressure-sensitive adhesive layer 3 irradiated with active energy rays, an acid is generated from a photoacid generator, and the color-developing compound develops color with this acid. The portion of the pressure-sensitive adhesive layer 3 that has been irradiated with active energy rays is colored, for example, in a blackish color according to the color development of the color-developing compound. The type of active energy ray as an external stimulus is determined by the type of photoacid generator (specifically, the wavelength of the active energy ray at which the photoacid generator generates acid). Examples of active energy rays include ultraviolet rays, visible light, infrared rays, X-rays, α-rays, β-rays, and γ-rays. From the viewpoint of diversity of use equipment and ease of handling, ultraviolet rays are preferably used as the active energy ray.

Examples of the photoacid generator include onium compounds that generate acid by irradiation with ultraviolet rays. The onium compound is provided in the form of, for example, an onium salt of an onium cation and an anion. As an onium cation, iodonium and sulfonium are mentioned, for example. Examples of anions include Cl ^- , Br ^- , I ^- , ZnCl ₃ ^- , HSO ₃ ^- , BF ₄ ^- , PF ₆ ^- , AsF ₆ ^- , SbF ₆ ^- , CH ₃ SO ₃ ^- , CF ₃ SO ₃ ^- , C ₄ F ₉ HSO ₃ ^- , (C ₆ F ₅ ) ₄ B ^- , and (C ₄ H ₉ ) ₄ B ^- . A photoacid generator may be used independently, or two or more types may be used together. As the photoacid generator, preferably, an onium salt (onium compound) composed of sulfonium and (C ₆ F ₅ ) ₄ B ^- and an onium salt (onium compound) composed of sulfonium and C ₄ F ₉ HSO ₃ ^- are mentioned. can

The compounding amount of the acid generator with respect to 100 parts by mass of the base polymer is, for example, 1 part by mass or more, preferably 2 parts by mass or more, more preferably 5 parts by mass or more, still more preferably 6 parts by mass. More than that. The blending amount is, for example, 20 parts by mass or less, preferably 15 parts by mass or less, and more preferably 10 parts by mass or less.

The blending amount of the acid generator with respect to 100 parts by mass of the color developing compound is, for example, 100 parts by mass or more, preferably 200 parts by mass or more, more preferably 300 parts by mass or more, still more preferably 330 parts by mass or more. more than the mass part. The blending amount is, for example, 1000 parts by mass or less, preferably 700 parts by mass or less, and more preferably 500 parts by mass or less.

In addition, the adhesive composition may contain a crosslinking agent from the viewpoint of introducing a crosslinked structure into the base polymer. Examples of the crosslinking agent include isocyanate crosslinking agents, epoxy crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, carbodiimide crosslinking agents, and metal chelate crosslinking agents. A crosslinking agent may be used independently and two or more types may be used together.

Examples of the isocyanate crosslinking agent include tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and hydrogenated xylylene diisocyanate. nate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, tetramethylxylylene diisocyanate, naphthaline diisocyanate, triphenylmethane triisocyanate , and polymethylene polyphenyl isocyanate. Moreover, derivatives of these isocyanates are also mentioned as an isocyanate crosslinking agent. As an isocyanate derivative, an isocyanurate modified body and a polyol modified body are mentioned, for example. As a commercially available isocyanate crosslinking agent, for example, Coronate L (trimethylolpropane adduct of tolylene diisocyanate, manufactured by Tosoh), Coronate HL (of hexamethylene diisocyanate) Trimethylolpropane adduct, manufactured by Tosoh), Coronate HX (isocyanurate of hexamethylene diisocyanate, manufactured by Tosoh), and Takenate D110N (trimethyl of xylylene diisocyanate) All-propane adducts, manufactured by Mitsui Chemicals) are exemplified.

Examples of the epoxy crosslinking agent include bisphenol A, epichlorohydrin-type epoxy resin, ethylene glycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, and glycerin triglycidyl ether , 1,6-hexanediol glycidyl ether, trimethylolpropane triglycidyl ether, diglycidylaniline, diamineglycidylamine, N,N,N',N'-tetraglycy dil-m-xylylenediamine, and 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane.

The crosslinking agent is preferably an isocyanate crosslinking agent and an epoxy crosslinking agent, more preferably a trimethylolpropane adduct of xylylene diisocyanate, and 1,3-bis(N,N- diglycidylaminomethyl)cyclohexane.

The compounding amount of the crosslinking agent is, for example, 0.01 part by mass or more, preferably 0.03 part by mass or more, with respect to 100 parts by mass of the base polymer, from the viewpoint of securing the cohesive force of the pressure-sensitive adhesive layer 3. From the viewpoint of ensuring good tackiness in the pressure-sensitive adhesive layer 3, the compounding amount of the crosslinking agent relative to 100 parts by mass of the base polymer is, for example, 10 parts by mass or less, preferably 5 parts by mass or less, more preferably 5 parts by mass or less. , 3 parts by mass or less, more preferably 1 part by mass or less.

When a crosslinking structure is introduced into the base polymer, a crosslinking catalyst may be used to effectively advance the crosslinking reaction. As a crosslinking catalyst, a metal type crosslinking catalyst is mentioned, for example.

Examples of the metal-based crosslinking catalyst include dibutyltin dilaurate, tetra-n-butyl titanate, tetraisopropyl titanate, ferric nasem, and butyltin oxide. The amount of the crosslinking catalyst used is, for example, 0.0001 parts by mass or more with respect to 100 parts by mass of the base polymer. In addition, the amount of copper used is, for example, 1 part by mass or less.

In addition, as a crosslinking agent, an isocyanate crosslinking agent (specifically, a trimethylolpropane adduct of xylylene diisocyanate) is blended, and as a crosslinking catalyst, a metal-based crosslinking catalyst (specifically, When blending dibutyltin dilaurate), preferably, acetylacetone is blended into the adhesive composition as a crosslinking inhibitor.

When acetylacetone is blended, acetylacetone coordinates to dibutyltin dilaurate. Thereby, advance of a crosslinking reaction can be suppressed before apply|coating an adhesive composition on a peeling film (1st peeling film 11) and forming a coating film. In addition, although described later in detail, by heating and drying at the time of coating film formation, acetylacetone can be removed and a crosslinking reaction can advance.

The amount of acetylacetone used is, for example, 100 parts by mass or more, preferably 10000 parts by mass or more, based on 100 parts by mass of the crosslinking catalyst. In addition, the amount of copper used is, for example, 50000 parts by mass or less.

Moreover, the adhesive composition may contain other components as needed. Examples of other components include polymerizable compounds and cured products thereof, photopolymerization initiators, silane coupling agents, tackifiers, plasticizers, softeners, antioxidants, surfactants, and antistatic agents.

Examples of the polymerizable compound include a monomer having one polymerizable functional group (ethylenically unsaturated double bond) (monofunctional monomer) and a monomer having a plurality of polymerizable functional groups (polyfunctional monomer). As a monofunctional monomer, monofunctional (meth)acrylate is mentioned, for example. As a polyfunctional monomer, polyfunctional (meth)acrylate is mentioned, for example.

In addition, when the adhesive composition contains a polymerizable compound, the adhesive composition preferably further contains a photopolymerization initiator.

The adhesive composition is composed of a base polymer, a compound that develops color by reaction with an acid, an acid generator, a crosslinking agent blended as necessary, a crosslinking catalyst blended as necessary, acetylacetone blended as needed, , It is obtained by blending other components blended as necessary in the above ratio.

The adhesive layer 3 is formed of an adhesive composition by a method described later.

And, the color change of the pressure-sensitive adhesive layer 3 is possible by an external stimulus.

In detail, when the adhesive composition contains a photoacid generator, when active energy rays are irradiated to the adhesive layer 3 as an external stimulus, an acid is generated from the photoacid generator, and a color-developing compound is formed by reaction with the acid. to color As a result, the pressure-sensitive adhesive layer 3 is discolored (the transmittance of visible light at a wavelength of 550 nm of the pressure-sensitive adhesive layer 3 is lowered).

And the pressure-sensitive adhesive layer 3 has a discolored portion 10 that is discolored by an external stimulus. In detail, the pressure-sensitive adhesive layer 3 has a discoloration portion 10 on at least a part of the pressure-sensitive adhesive layer 3 . Preferably, the pressure-sensitive adhesive layer (3) has a discolored portion (10) in a part of the pressure-sensitive adhesive layer (3). The visible light transmittance of the color-changing portion 10 at a wavelength of 550 nm is, for example, less than 20%.

The thickness of the pressure-sensitive adhesive layer 3 is, for example, 10 μm or more, preferably 15 μm or more, from the viewpoint of ensuring sufficient adhesiveness to the adherend 2 . From the viewpoint of handleability, the thickness of the pressure-sensitive adhesive layer 3 is, for example, 300 μm or less, preferably 100 μm or less, and more preferably 50 μm or less.

4. Oxygen Barrier Layer

The oxygen barrier layer 4 has an oxygen transmission rate of a predetermined level or less. Therefore, penetration of oxygen into the pressure-sensitive adhesive layer 3 can be suppressed by the oxygen barrier layer 4 . As a result, although described later in detail, deterioration of the discolored portion 10 due to external light can be suppressed.

Specifically, the oxygen transmission rate of the oxygen barrier layer 4 is 200 cm ³ /m ² ·day·atm or less, preferably 150 cm ³ /m ² ·day·atm or less, more preferably 50 cm ³ /m ² ·day·atm or less, more preferably 20 cm ³ /m ² ·day·atm or less. In addition, the copper oxygen transmission rate is, for example, 1 cm ³ /m ² ·day·atm or more.

If the oxygen permeability of the oxygen barrier layer 4 is equal to or less than the above upper limit, penetration of oxygen into the pressure-sensitive adhesive layer 3 can be suppressed. As a result, deterioration of the discolored portion 10 due to external light can be suppressed.

The oxygen transmission rate of the oxygen barrier layer 4 is determined by adjusting the material of the polymer film described later (in other words, the type of the oxygen barrier layer 4) and/or the thickness of the oxygen barrier layer 4 described later. It can be adjusted within the above range.

On the other hand, the oxygen transmission rate of the oxygen barrier layer 4 can be measured according to JIS K7126-2 Annex A at 23°C and 55% relative humidity.

The oxygen barrier layer 4 is, for example, a transparent polymer film. Examples of the material for the polymer film include polyester resins, (meth)acrylic resins (acrylic resins and/or methacrylic resins), olefin resins, polycarbonate resins, polyethersulfone resins, polyarylate resins, and melamine resins. , polyamide resins, polyimide resins, cellulose resins, and polystyrene resins.

Examples of the polyester resin include polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate, preferably polyethylene terephthalate (PET). As a (meth)acrylic resin, polymethacrylate is mentioned, for example. As an olefin resin, polyethylene, a polypropylene, and a cycloolefin polymer (COP) are mentioned, for example.

As the material of the polymer film, preferably, a polyester resin and a (meth)acrylic resin are exemplified from the viewpoint of adjusting the oxygen permeability of the oxygen barrier layer 4 to the above range.

The material of the polymer film may be used alone or in combination of two or more.

Further, as the oxygen barrier layer 4, a film formed of a biomass-derived component (eg, isocarbide) can also be used.

In the second step of the manufacturing method of the layered product 1 described later, when the active energy ray is irradiated from the side of the oxygen barrier layer 4, the active energy ray is transmitted through the oxygen barrier layer 4. An oxygen barrier layer is selected.

As an oxygen barrier layer that transmits active energy rays, an oxygen barrier layer that transmits ultraviolet rays is exemplified.

As an oxygen barrier layer that transmits ultraviolet rays, for example, a polymer film having the above-mentioned transparency is exemplified.

The total light transmittance (JIS K 7375-2008) of the oxygen barrier layer that transmits ultraviolet rays is, for example, 80% or more, preferably 85% or more.

The thickness of the oxygen barrier layer 4 is, for example, 10 μm or more, preferably 22 μm or more, and more preferably 30 μm or more. Further, the copper thickness is, for example, 200 μm or less, preferably 100 μm or less.

5. Manufacturing method of laminate

The manufacturing method of a laminated body forms a discoloration part 10 in the adhesive layer 3 by the 1st process of disposing the adhesive layer 3 on one side of the thickness direction of the adherend 2, and an external stimulus. A second step of doing, and a third step of disposing the oxygen barrier layer 4 on one side of the pressure-sensitive adhesive layer 3 in the thickness direction. Hereinafter, the manufacturing method of the laminated body 1 is divided into the order of each process, and is demonstrated.

Specifically, a 1st method and a 2nd method are mentioned.

The first method is a method of arranging the pressure-sensitive adhesive layer 3 on one surface of the adherend 2 in the thickness direction before forming the discoloration portion 10 on the pressure-sensitive adhesive layer 3 .

The second method is a method of disposing the pressure-sensitive adhesive layer 3 on one surface of the adherend 2 in the thickness direction after forming the discoloration portion 10 on the pressure-sensitive adhesive layer 3 .

5-1. Method 1

In the first method, before forming the discoloration portion 10 on the pressure-sensitive adhesive layer 3, the pressure-sensitive adhesive layer 3 is disposed on one surface of the adherend 2 in the thickness direction. That is, in the first method, after disposing the pressure-sensitive adhesive layer 3 on one surface of the adherend 2 in the thickness direction, the discolored portion 10 is formed on the pressure-sensitive adhesive layer 3 . When the adhesive layer 3 is arrange|positioned, since the adhesive layer 3 is transparent, the presence or absence of a foreign material and air bubbles can be inspected suitably.

In detail, the first method includes method 1A, method 1B, and method 1C. In method 1A, the first step, the second step, and the third step are performed in this order. In the 1st method, the 3rd process, the 1st process, and the 2nd process are implemented in order. In 1C method, a 1st process, a 3rd process, and a 2nd process are implemented in order.

<Method 1A>

In method 1A, the first step, the second step, and the third step are performed in this order.

In the first step, the pressure-sensitive adhesive layer 3 is disposed on one surface of the adherend 2 in the thickness direction.

In order to dispose the pressure-sensitive adhesive layer 3 on one surface of the adherend 2 in the thickness direction, first, as shown in Fig. 2A, the adherend 2 is prepared.

Next, the pressure-sensitive adhesive layer 3 is prepared.

In order to prepare the pressure-sensitive adhesive layer 3, for example, it can be produced by applying the above-described adhesive composition on a release film (first release film 11) to form a coating film, and then drying the coating film. .

As a peeling film, the plastic film which has flexibility is mentioned, for example. As a plastic film, a polyethylene terephthalate film, a polyethylene film, a polypropylene film, and a polyester film are mentioned, for example. The thickness of the peeling film is, for example, 3 μm or more. In addition, the copper thickness is 200 μm or less, for example. The surface of the release film is preferably subjected to release treatment.

As a method of applying the adhesive composition, for example, roll coating, kiss roll coating, gravure coating, reverse coating, roll brush, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, and die coating. The drying temperature of the coating film is, for example, 50°C or higher. Also, the drying temperature is, for example, 200°C or less. The drying time is, for example, 5 seconds or more. In addition, the drying time is, for example, 20 minutes or less.

When the adhesive composition contains a crosslinking agent, the crosslinking reaction proceeds simultaneously with the above drying or by aging thereafter. Aging conditions are appropriately set depending on the type of crosslinking agent. The aging temperature is, for example, 20°C or higher. In addition, the copper aging temperature is, for example, 160°C or less. The aging time is, for example, 1 minute or longer. In addition, the same aging time is 7 days or less, for example.

Further, when the adhesive composition contains acetylacetone (in other words, when acetylacetone is coordinated to dibutyltin dilaurate), upon drying, acetylacetone coordinated to dibutyltin dilaurate is Removed. Thereby, a crosslinking reaction can advance.

Moreover, you may laminate|stack a peeling film (2nd peeling film) further on the adhesive layer 3 on the 1st peeling film 11 before or after aging. The second release film is, for example, a flexible plastic film subjected to surface release treatment. As the 2nd peeling film, the thing similar to what was mentioned above about the 1st peeling film 11 can be used.

As described above, the pressure-sensitive adhesive layer 3 in which the adhesive face is covered and protected by the release film can be manufactured. When using the adhesive layer 3, each peeling film peels off from the adhesive layer 3 as needed.

And as shown in FIG. 2B, this adhesive layer 3 is transcribe|transferred to one surface of the to-be-adhered body 2 in the thickness direction. Thereby, the adhesive layer 3 is arrange|positioned on one surface of the to-be-adhered body 2 in the thickness direction.

In the second step, as shown in Fig. 2C, the discolored portion 10 is formed in the pressure-sensitive adhesive layer 3 by an external stimulus.

Specifically, from the pressure-sensitive adhesive layer 3 side and/or the adherend 2 side, a mask pattern (not shown) for masking a predetermined area in the pressure-sensitive adhesive layer 3 is interposed therebetween, and the pressure-sensitive adhesive layer 3 For , active energy rays as external stimuli are irradiated. Thereby, the part not masked by the mask pattern in the adhesive layer 3 is discolored.

In this step, acid is generated from the photoacid generator in the portion of the pressure-sensitive adhesive layer 3 that has been irradiated with active energy rays, and the color-developing compound develops color by reaction with the acid. As a result, the discoloration portion 10 is formed in the pressure-sensitive adhesive layer 3 .

In the 3rd process, as shown in FIG. 2D, the oxygen barrier layer 4 is arrange|positioned on one side of the thickness direction of the adhesive layer 3. In this way, the layered product 1 is obtained.

<Method 1B>

In the 1st method, the 3rd process, the 1st process, and the 2nd process are implemented in order.

In the third step, the oxygen barrier layer 4 is disposed on one side of the pressure-sensitive adhesive layer 3 in the thickness direction. In order to dispose the oxygen barrier layer 4 on one side of the pressure-sensitive adhesive layer 3 in the thickness direction, first, as shown in FIG. 3A, by the above-mentioned method, the pressure-sensitive adhesive layer 3 ) to form

Next, as shown in FIG. 3B, an oxygen barrier layer 4 is disposed on one side of the pressure-sensitive adhesive layer 3 in the thickness direction. Thereby, the variable-color adhesive sheet S which is provided with the 1st peeling film 11, the adhesive layer 3, and the oxygen barrier layer 4 in order is comprised.

In the first step, as shown in Fig. 3C, the pressure-sensitive adhesive layer 3 is disposed on one side of the adherend 2 in the thickness direction. Specifically, the 1st peeling film 11 is peeled from the adhesive layer 3, and the adhesive layer 3 is arrange|positioned on one side of the to-be-adhered body 2 in the thickness direction.

In the second step, as shown in Fig. 3D, active energy rays are irradiated from the side of the oxygen barrier layer 4 and/or the side of the adherend 2 in the same manner as described above, and applied to the pressure-sensitive adhesive layer 3. Form the discoloration portion (10). In this way, the layered product 1 is obtained.

<Method 1C>

In 1C method, a 1st process, a 3rd process, and a 2nd process are implemented in order.

In a 1st process, the adhesive layer 3 is arrange|positioned on one side of the thickness direction of the to-be-adhered body 2 by the method similar to the above.

Specifically, first, as shown in Fig. 4A, the adherend 2 is prepared. Next, the adhesive layer 3 is prepared on the 1st peeling film 11 by the method similar to the above. Subsequently, as shown in FIG. 4B , the pressure-sensitive adhesive layer 3 is transferred to one side of the adherend 2 in the thickness direction by a method similar to the above. Thereby, the adhesive layer 3 is arrange|positioned on one surface of the to-be-adhered body 2 in the thickness direction.

In the third step, as shown in Fig. 4C, the oxygen barrier layer 4 is disposed on one side of the pressure-sensitive adhesive layer 3 in the thickness direction.

In the second step, as shown in Fig. 4D, active energy rays are irradiated from the side of the oxygen barrier layer 4 and/or the side of the adherend 2 in the same manner as described above, and applied to the pressure-sensitive adhesive layer 3. Form the discoloration portion (10). In this way, the layered product 1 is obtained.

5-2. 2nd method

In the second method, after forming the discoloration portion 10 on the pressure-sensitive adhesive layer 3, the pressure-sensitive adhesive layer 3 is disposed on one surface of the adherend 2 in the thickness direction. Therefore, in the second method, the discolored portion 10 can be formed in the pressure-sensitive adhesive layer 3 without applying an external stimulus to the adherend 2 .

Specifically, the second method includes method 2A, method 2B, and method 2C. In the 2nd method, the 2nd process, the 1st process, and the 3rd process are implemented in order. In the 2B method, the 2nd process, the 3rd process, and the 1st process are implemented in order. In the 2C method, the 3rd process, the 2nd process, and the 1st process are implemented in order.

<Method 2A>

In the 2nd method, the 2nd process, the 1st process, and the 3rd process are implemented in order.

In the second step, the discolored portion 10 is formed in the pressure-sensitive adhesive layer 3 by an external stimulus.

In order to form the discoloration portion 10 in the pressure-sensitive adhesive layer 3 by an external stimulus, first, as shown in FIG. ) to prepare Next, as shown in Fig. 5B, from the pressure-sensitive adhesive layer 3 side and/or the first peeling film 11 side, active energy rays are irradiated by a method similar to the above, and the color change is applied to the pressure-sensitive adhesive layer 3. form (10).

In the first step, as shown in FIG. 5C , the pressure-sensitive adhesive layer 3 is disposed on one side of the adherend 2 in the thickness direction. Specifically, the 1st peeling film 11 is peeled from the adhesive layer 3, and the adhesive layer 3 is arrange|positioned on one side of the to-be-adhered body 2 in the thickness direction.

In the third step, as shown in Fig. 5D, the oxygen barrier layer 4 is disposed on one side of the pressure-sensitive adhesive layer 3 in the thickness direction. In this way, the layered product 1 is obtained.

<Method 2B>

In the 2B method, the 2nd process, the 3rd process, and the 1st process are implemented in order.

In the second step, the discolored portion 10 is formed in the pressure-sensitive adhesive layer 3 by an external stimulus.

In order to form the discoloration portion 10 in the pressure-sensitive adhesive layer 3 by an external stimulus, first, as shown in FIG. 6A , the pressure-sensitive adhesive layer 3 ) to prepare Next, as shown in Fig. 6B, from the pressure-sensitive adhesive layer 3 side and/or the first peeling film 11 side, an active energy ray is irradiated by a method similar to the above, and the color change is applied to the pressure-sensitive adhesive layer 3. form (10).

In the 3rd process, as shown in FIG. 6C, the oxygen barrier layer 4 is arrange|positioned on one side of the thickness direction of the adhesive layer 3.

In the first step, as shown in Fig. 6D, the pressure-sensitive adhesive layer 3 is disposed on one side of the adherend 2 in the thickness direction. Specifically, the 1st peeling film 11 is peeled from the adhesive layer 3, and the adhesive layer 3 is arrange|positioned on one side of the to-be-adhered body 2 in the thickness direction. In this way, the layered product 1 is obtained.

<Method 2C>

In the 2C method, the 3rd process, the 2nd process, and the 1st process are implemented in order.

In the third step, the oxygen barrier layer 4 is disposed on one side of the pressure-sensitive adhesive layer 3 in the thickness direction. In order to dispose the oxygen barrier layer 4 on one side of the pressure-sensitive adhesive layer 3 in the thickness direction, first, as shown in FIG. 7A, the pressure-sensitive adhesive layer 3 ) to form

Next, as shown in FIG. 7B, an oxygen barrier layer 4 is disposed on one surface of the pressure-sensitive adhesive layer 3 in the thickness direction. Thereby, the variable-color adhesive sheet S which is provided with the 1st peeling film 11, the adhesive layer 3, and the oxygen barrier layer 4 in order is comprised.

In the second step, the discolored portion 10 is formed in the pressure-sensitive adhesive layer 3 by an external stimulus.

In order to form the discolored portion 10 in the pressure-sensitive adhesive layer 3 by an external stimulus, as shown in FIG. 7C, from the oxygen barrier layer 4 side and/or the first peeling film 11 side, as described above. By the same method, active energy rays are irradiated to form the discolored portion 10 in the pressure-sensitive adhesive layer 3 .

In the first step, as shown in Fig. 7D, the pressure-sensitive adhesive layer 3 is disposed on one surface of the adherend 2 in the thickness direction. Specifically, the 1st peeling film 11 is peeled from the adhesive layer 3, and the adhesive layer 3 is arrange|positioned on one side of the to-be-adhered body 2 in the thickness direction. In this way, the layered product 1 is obtained.

6. Action effect

The laminate 1 includes an oxygen barrier layer 4 having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. Therefore, deterioration of the discolored portion 10 due to external light can be suppressed.

In detail, when the discolored portion 10 is exposed to oxygen, deterioration of the discolored portion 10 due to external light is promoted. On the other hand, the laminate 1 includes an oxygen barrier layer 4 having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. Therefore, penetration of oxygen into the pressure-sensitive adhesive layer 3 can be suppressed. As a result, deterioration of the discolored portion 10 due to external light can be suppressed.

The manufacturing method of the layered product 1 includes a third step of disposing an oxygen barrier layer 4 having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less on one side of the pressure-sensitive adhesive layer 3 in the thickness direction. do. Therefore, the laminate 1 capable of suppressing deterioration of the discolored portion 10 due to external light can be manufactured.

7. Variations

Next, a modified example of one embodiment is described. In each of the following modifications, the same reference numerals are assigned to members and steps similar to those of the above-described embodiment, and detailed descriptions thereof are omitted. Moreover, each modified example can be combined suitably. In addition, each modified example can exhibit the same operation and effect as one embodiment other than those specifically described.

In the above description, the external stimulus is an active energy ray. On the other hand, the external stimulus may be heat.

In the above description, after the adhesive layer 3 is prepared on the upper surface of the release film 11, the adhesive layer 3 is transferred (placed) to the adherend 2. On the other hand, without preparing the adhesive layer 3 on the upper surface of the peeling film 11, the adhesive composition is applied directly to the adherend 2, and the adhesive layer 3 is disposed on the adherend 2. may be

In the above description, the layered product 1 is provided with the adherend 2, the pressure-sensitive adhesive layer 3, and the oxygen barrier layer 4 sequentially toward one side in the thickness direction. On the other hand, the layered product 1 may further include an active energy ray blocking layer 5 . Specifically, the laminate 1 may further include an active energy ray blocking layer 5 on one side of the oxygen barrier layer 4 in the thickness direction and/or on the other side of the oxygen barrier layer 4 in the thickness direction. may be More specifically, the laminate 1 may further include an active energy ray blocking layer 5 on one side of the oxygen barrier layer 4 in the thickness direction, as shown in FIG. 8A . In addition, the layered product 1 may further include an active energy ray blocking layer 5 on the other side of the thickness direction of the oxygen barrier layer 4, as shown in FIG. 8B. In addition, as shown in FIG. 8C , the laminate 1 includes an active energy ray blocking layer 5 on one side of the oxygen barrier layer 4 in the thickness direction and on the other side of the oxygen barrier layer 4 in the thickness direction. may be further provided.

When the layered product 1 is provided with the active energy ray blocking layer 5, further discoloration of the discolored portion 10 by the active energy ray can be suppressed.

As the active energy ray blocking layer 5, an ultraviolet ray blocking layer is exemplified.

The ultraviolet blocking layer is a layer that blocks (absorbs or reflects) ultraviolet rays. When the layered product 1 is provided with an ultraviolet ray blocking layer, further discoloration of the discolored portion 10 by ultraviolet rays can be suppressed.

As the ultraviolet blocking layer, specifically, an ultraviolet absorbing layer and an ultraviolet reflective layer are exemplified.

Examples of the ultraviolet absorbing layer include a resin film containing a UV absorber and an adhesive tape containing a UV absorber.

The average transmittance of the ultraviolet absorbing layer at a wavelength of 300 nm or more and 400 nm or less is, for example, 15% or less, preferably 10% or less.

The ultraviolet ray reflection layer is a layer that reflects ultraviolet rays using light scattering, for example. As an ultraviolet reflection layer, a multilayer optical film is mentioned, for example.

The active energy ray blocking layer 5 is disposed on the other side of the thickness direction of the oxygen barrier layer 4 and/or the other side of the thickness direction of the oxygen barrier layer 4 by using, for example, a known adhesive.

In addition, in the manufacturing method of the laminated body 1 mentioned above, the timing of disposing the active energy ray blocking layer 5 is not specifically limited. On the other hand, in the case of performing the second step of forming the discolored portion 10 in the pressure-sensitive adhesive layer 3 by ultraviolet rays after disposing the ultraviolet ray blocking layer as the active energy ray blocking layer 5, the ultraviolet ray blocking layer and An ultraviolet ray is irradiated from the opposite side to form a discolored portion (10) in the pressure-sensitive adhesive layer (3).

The thickness of the active energy ray blocking layer 5 is, for example, 10 μm or more, preferably 50 μm or more. Further, the copper thickness is, for example, 1000 μm or less, preferably 300 μm or less.

In addition, the layered product 1 may further include a substrate 20 . The position of the substrate 20 in the layered product 1 is not particularly limited.

The substrate 20 is, for example, a plastic film having flexibility. Examples of the constituent material of the plastic film include polyolefin, polyester, polyamide, polyimide, polyvinyl chloride, polyvinylidene chloride, cellulose, polystyrene, and polycarbonate. Examples of the polyolefin include polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, ethylene/propylene copolymer, ethylene/1-butene copolymer, ethylene/vinyl acetate copolymer, and ethylene. • Ethyl acrylate copolymer, and ethylene/vinyl alcohol copolymer. As polyester, polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate are mentioned, for example. Examples of the polyamide include polyamide 6, polyamide 6 and 6, and partially aromatic polyamide.

In addition, the layered product 1 may further include an intermediate layer 30 . The position of the intermediate layer 30 in the laminate 1 is not particularly limited.

As the intermediate layer 30, for example, those similar to those described for the adherend 2, the oxygen barrier layer 4, and the substrate 20 described above can be employed.

Moreover, as the intermediate|middle layer 30, the adhesive layer formed from a well-known adhesive, an optical film, and various functional layers are also mentioned, for example.

From the above, the layered product 1 may further include at least one selected from the group consisting of the active energy ray blocking layer 5, the substrate 20, and the intermediate layer 30.

As a specific example of such a case, as shown in FIG. 9A, the adherend 2, the pressure-sensitive adhesive layer 3, the intermediate layer 30, the active energy ray blocking layer 5, and the oxygen barrier layer 4 The laminated body 1 which is provided sequentially toward one side in the thickness direction is mentioned.

As a specific example, as shown in Fig. 9B, the adherend 2, the pressure-sensitive adhesive layer 3, the substrate 20, the active energy ray blocking layer 5, and the oxygen barrier layer 4 are formed. The laminated body 1 provided in order towards one side in the thickness direction is mentioned.

Further, as a specific example, as shown in FIG. 9C, the adherend 2, the pressure-sensitive adhesive layer 3, the oxygen barrier layer 4, the active energy ray blocking layer 5, and the base material 20 are formed. The laminated body 1 provided in order towards one side in the thickness direction is mentioned.

Further, as a specific example, as shown in Fig. 9D, the adherend 2, the pressure-sensitive adhesive layer 3, the intermediate layer 30, the substrate 20, the active energy ray blocking layer 5, and oxygen A layered body 1 provided with the barrier layer 4 sequentially toward one side in the thickness direction is exemplified.

Further, as a specific example, as shown in Fig. 9E, the adherend 2, the pressure-sensitive adhesive layer 3, the intermediate layer 30, the active energy ray blocking layer 5, the oxygen barrier layer 4, , a layered body 1 having the base material 20 sequentially toward one side in the thickness direction.

In addition, the layered product 1 may further include a surface protective layer 40 on the outermost surface (one side in the thickness direction) of the layered product 1 from the viewpoint of surface protection.

As the surface protective layer 40, a resin film is exemplified.

An aspect in which the layered product 1 includes the surface protective layer 40 will be described with the case of the layered product 1 shown in FIG. 9B described above.

As shown in FIG. 10 , the surface protective layer 40 is disposed on the outermost surface of the layered product 1 (one surface of the oxygen barrier layer 4 in the thickness direction). That is, the laminate 1 includes an adherend 2, an adhesive layer 3, a base material 20, an active energy ray blocking layer 5, an oxygen barrier layer 4, and a surface protective layer. (40) is sequentially provided toward one side in the thickness direction.

On the other hand, in the description of the surface protective layer 40 described above, the laminate 1 shown in FIG. 9B was mentioned, but other laminates (e.g., FIGS. 1, 8A to 8C, 9A, 9C and FIG. The same applies to the laminate shown in 9D).

8. Variable color adhesive sheet

As shown in Fig. 11, the color-changing pressure-sensitive adhesive sheet S includes a first peeling film 11, an adhesive layer 3, and an oxygen barrier layer 4 sequentially toward one side in the thickness direction. More specifically, the variable-color adhesive sheet S includes a first peeling film 11, a pressure-sensitive adhesive layer 3 directly disposed on the upper surface (on one side in the thickness direction) of the first peeling film 11, and a pressure-sensitive adhesive. An oxygen barrier layer 4 is provided directly on the upper surface of the layer 3 (on one side in the thickness direction). When the oxygen barrier layer 4 is disposed directly on the upper surface (on one side in the thickness direction) of the pressure-sensitive adhesive layer 3, the oxygen barrier property is excellent.

The variable color adhesive sheet S includes an oxygen barrier layer 4 having an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. Therefore, the laminate 1 capable of suppressing deterioration of the discolored portion 10 due to external light can be manufactured.

The variable color adhesive sheet S may further include an active energy ray blocking layer 5 . Specifically, the color-changing pressure-sensitive adhesive sheet S is applied to the other side in the thickness direction of the pressure-sensitive adhesive layer 3, and/or one side in the thickness direction of the oxygen barrier layer 4, and/or the thickness direction of the oxygen barrier layer 4. On the other hand, an active energy ray blocking layer 5 may be provided.

As the active energy ray blocking layer 5, preferably, an ultraviolet ray absorbing layer, more preferably, an adhesive tape containing an ultraviolet ray absorbent is exemplified.

Example

The present invention will be described in detail by showing examples below, but the present invention is not limited to the examples. In addition, the specific numerical values such as the compounding amount (content), physical property values, and parameters described below are the compounding amounts (content), physical property values, and parameters corresponding to them described in the above “Specific Content for Carrying Out the Invention”. It can be substituted with the upper limit (numerical value defined as "below" or "less than") or the lower limit (numerical value defined as "greater than" or "exceeding") of the same.

<Preparation of base polymer>

Preparation Example 1

In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas introduction pipe, 95 parts by mass of n-butyl acrylate (BA), 5 parts by mass of acrylic acid (AA), and 2,2'- as a polymerization initiator were added. A mixture containing 0.2 parts by mass of azobisisobutyronitrile (AIBN) and 122 parts by mass of ethyl acetate as a solvent was stirred at 60°C for 7 hours in a nitrogen atmosphere (polymerization reaction). In this way, a polymer solution containing an acrylic polymer was obtained. The weight average molecular weight (Mw) of the acrylic polymer in this polymer solution was 600,000.

Preparation Example 2

In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet pipe, 63 parts by mass of 2-ethylhexyl acrylate (2EHA), 9 parts by mass of methyl methacrylate (MMA), and 2-hydroxy acrylate 13 parts by mass of ethyl (HEA), 15 parts by mass of N-vinyl-2-pyrrolidone (NVP), 0.2 part by mass of 2,2'-azobisisobutyronitrile (AIBN) as a polymerization initiator, and a solvent A mixture containing 233 parts by mass of ethyl acetate as the mixture was stirred at 60°C for 7 hours in a nitrogen atmosphere (polymerization reaction). This obtained a polymer solution (polymer solution) containing an acrylic polymer. The weight average molecular weight (Mw) of the acrylic polymer in this polymer solution was 1.2 million.

Example 1

<Preparation of adhesive composition>

The following components per 100 parts by mass of the acrylic polymer (base polymer) were uniformly mixed with the above polymer solution containing the acrylic polymer of Production Example 1 to prepare an adhesive composition.

Compounds that develop color by reaction with acid: Leuco pigment, 2'-anilino-6'-(N-ethyl-N-isopentylamino)-3'-methylspiro[phthalide-3,9'-[ 9H] Xanthen] (trade name: S-205, manufactured by Yamada Chemical Industry Co., Ltd.) 2 parts by mass

Acid generator: Photoacid generator, onium salt of sulfonium and (C ₆ F ₅ ) ₄ B ^- (trade name: CPI-310B, manufactured by San Afro) 7 parts by mass

Crosslinking agent: Epoxy crosslinking agent, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, tetrad C (manufactured by Mitsubishi Gas Chemical Co., Ltd.), 0.05 parts by mass (based on solid content)

<Manufacture of pressure-sensitive adhesive layer>

An adhesive composition was applied to a release film (polyester film, thickness 38 µm, Mitsubishi Juici Co., Ltd., MRF#38) having one side serving as a release surface to form a coating film. Next, this coating film was dried at 132°C for 3 minutes to form an adhesive layer having a thickness of 25 µm. To this pressure-sensitive adhesive layer, a release film (polyester film, thickness 38 μm, MRF#38 manufactured by Mitsubishi Jushi Corporation) having a thickness of 38 μm in which one side of the polyester film is a release surface was bonded. Thereafter, an aging treatment was performed at 60°C for 1 day to promote a crosslinking reaction in the pressure-sensitive adhesive layer.

<Manufacture of laminated body>

On one side of the thickness direction of eagle glass (thickness: 0.55 mm, manufactured by Matsunami Glass Co., Ltd.), the above pressure-sensitive adhesive layer 25 μm, UVA-TAC 32 μm, UVA-OCA 100 μm (ultraviolet ray blocking layer), and the oxygen barrier layer shown in Table 1 placed sequentially. In this way, a laminate was manufactured.

On the other hand, details of UVA-TAC and UVA-OCA are as follows.

UVA-TAC: A film comprising KC2UA (TAC film, manufactured by Konica Minolta Co., Ltd.) and a hard coating layer sequentially (by forming a hard coating layer (thickness: 7 μm) on one side of KC2UA (thickness: 25 μm) by hard coating treatment) obtained (thickness: 32 μm))

UVA-OCA: UV blocking layer, adhesive tape having an ultraviolet absorbing function, trade name "CS9934U", thickness 100 μm, manufactured by Nitto Denko Co., Ltd.

PET 75 μm: PET film, thickness 75 μm, trade name “G981 E75”, manufactured by Mitsubishi Chemical Corporation

Example 2, Example 3, Example 4, Comparative Example 1 and Comparative Example 2

A laminate was manufactured in the same manner as in Example 1.

However, the type of oxygen barrier layer was changed according to Table 1.

On the other hand, details of each oxygen barrier layer are as follows.

PET 25 μm: PET film, thickness 25 μm, trade name “T602 E25”, manufactured by Mitsubishi Chemical Corporation

Acry l20 μm: Acrylic film, thickness 20 μm, trade name “RV-20UB”, manufactured by Toyo Kohan Co., Ltd.

TAC 28 μm: TAC film, thickness 28 μm,

COP 13 μm: COP film, thickness 13 μm, trade name “ZF14-013”, manufactured by Nippon Zeon Co., Ltd.

PC 70 μm: PC film, thickness 70 μm, trade name “DURABIO”, a film produced by Mitsubishi Chemical Co., Ltd.

Example 5

A laminate was manufactured in the same manner as in Example 4. However, as an acid generator, the following components were used.

Acid generator: Photoacid generator, onium salt of sulfonium and C ₄ F ₉ HSO ₃ ^- (trade name: SP056, manufactured by ADEKA) 7 parts by mass

Example 6

A laminate was manufactured in the same manner as in Example 4. However, the following adhesive composition was used.

<Preparation of adhesive composition>

The following components per 100 parts by mass of the acrylic polymer (base polymer) were uniformly mixed with the above polymer solution containing the acrylic polymer of Production Example 2 to prepare an adhesive composition.

Compounds that develop color by reaction with acid: Leuco pigment, 2'-anilino-6'-(N-ethyl-N-isopentylamino)-3'-methylspiro[phthalide-3,9'-[ 9H] Xanthen] (trade name: S-205, manufactured by Yamada Chemical Industry Co., Ltd.) 2 parts by mass

Acid generator: Photoacid generator, (trade name: CPI-310B, manufactured by San-Apro) 7 parts by mass

Isocyanate crosslinking agent: (trade name "Takenate D110N", 75% ethyl acetate solution of trimethylolpropane adduct of xylylene diisocyanate, manufactured by Mitsui Chemicals Co., Ltd.) 0.25 parts by mass (solid content equivalent)

Crosslinking catalyst: dibutyltin dilaurate (trade name "OL-1", 1 mass% ethyl acetate solution, manufactured by Tokyo Fine Chemical Co., Ltd.) 0.01 parts by mass (solid content equivalent)

Crosslinking inhibitor (ligand for crosslinking catalyst): 3 parts by mass of acetylacetone

Example 7

A laminate was manufactured in the same manner as in Example 4. However, the following adhesive composition was used.

<Preparation of adhesive composition>

The following components per 100 parts by mass of the acrylic polymer (base polymer) were uniformly mixed with the above polymer solution containing the acrylic polymer of Production Example 2 to prepare an adhesive composition.

Compounds that develop color by reaction with acid: Leuco pigment, 2'-anilino-6'-(N-ethyl-N-isopentylamino)-3'-methylspiro[phthalide-3,9'-[ 9H] Xanthen] (trade name: S-205, manufactured by Yamada Chemical Industry Co., Ltd.) 2 parts by mass

Acid generator: Photoacid generator, (trade name: SP-056, manufactured by ADEKA) 7 parts by mass

Isocyanate crosslinking agent: (trade name "Takenate D110N", 75% ethyl acetate solution of trimethylolpropane adduct of xylylene diisocyanate, manufactured by Mitsui Chemicals Co., Ltd.) 0.25 parts by mass (solid content equivalent)

Crosslinking catalyst: dibutyltin dilaurate (trade name "OL-1", 1 mass% ethyl acetate solution, manufactured by Tokyo Fine Chemical Co., Ltd.) 0.01 parts by mass (solid content equivalent)

Crosslinking inhibitor (ligand for crosslinking catalyst): 3 parts by mass of acetylacetone

<evaluation>

(oxygen permeability)

For each oxygen barrier layer, the oxygen transmission rate was measured according to Annex A of JIS K7126-2 at 23°C and 55% relative humidity. The results are shown in Table 1.

(weather resistance test)

In the laminates of each Example and each Comparative Example, the samples were irradiated with ultraviolet rays. Specifically, the pressure-sensitive adhesive sheet (pressure-sensitive adhesive layer) in the sample was irradiated with ultraviolet rays from the eagle glass side through the glass in an environment of 23°C and 50% relative humidity (by the UV irradiation, the pressure-sensitive adhesive layer The leuco dye and the photoacid generator in the reaction were reacted). In this UV irradiation, a UV-LED lamp with a wavelength of 365 nm in a UV-LED irradiation device manufactured by Quark Technology (model number "QEL-350-RU6W-CW-MY") was used as a light source, and the cumulative irradiation light amount was 8000 mJ/ It was set as cm ² (the cumulative amount of irradiation light in the range of wavelength 320 to 390 nm). As described above, a colored laminate was produced. Next, the average transmittance of the colored layered product and the values of L ^* , a ^* , and b ^* were measured.

Subsequently, a super xenon lamp having an illuminance of 120 W in a wavelength range of 300 to 400 nm was irradiated from the side of the oxygen barrier layer for 24 hours using a super xenon weather meter SX75 manufactured by Suga Test Instruments. In this way, a laminate after irradiation for 24 hours was obtained.

Next, the values of average transmittance, L ^* , a ^* , and b ^* of the layered product and the layered product after irradiation for 24 hours were measured.

Regarding the method of measuring the values of average transmittance, L ^* , a ^* , and b ^* , specifically, in each sample (laminate and laminate after 24 hours irradiation), so that light hits from the eagle glass side, It was installed in a transmittance measuring device (U4150 type spectrophotometer, manufactured by Hitachi High-Tech Science Co., Ltd.). Then, the values of average transmittance, L ^* , a ^* , and b ^* in a wavelength range of 400 nm to 700 nm were measured, respectively.

Specifically, the average transmittance (T1) of the laminate at a wavelength of 400 nm to 700 nm, L ^* (L1 ^* ) for the laminate, a ^* (a1 ^* ) for the laminate, and b for the laminate ^* (b1 ^* ), the average transmittance (T2) of the laminate after irradiation for 24 hours at a wavelength of 400 nm to 700 nm, L ^* (L2 ^* ) for the laminate after irradiation for 24 hours, and the laminate after irradiation for 24 hours a ^* (a2 ^* ) for and b ^* (b2 ^* ) for the laminate after irradiation for 24 hours were measured, respectively.

Then, the color difference (ΔE) was calculated based on the following formula (1).

ΔE=((L2 ^* -L1 ^* ) ² + (a2 ^* -a1 ^* ) ² + (b2 ^* -b1 ^* ) ² ) ^1/2 (1)

The results of T1, T2, and color difference (ΔE) are shown in Table 1.

In addition, although the said invention was provided as embodiment of an illustration of this invention, this is only a mere illustration and it must not interpret it limitedly. Modifications of the present invention obvious to those skilled in the art in the art are included in the scope of the later claims.

The laminate, the manufacturing method of the laminate, and the variable color pressure-sensitive adhesive sheet of the present invention are suitably used in the manufacturing process of a display panel.

1 laminate
2 adherend
3 adhesive layer
4 oxygen barrier layer
5 active energy ray blocking layer
10 discoloration part
20 entries
30 middle layer
40 surface protective layer
S variable color adhesive sheet

Claims (7)

An adherend, an adhesive layer, and an oxygen barrier layer are sequentially provided in the thickness direction,
The pressure-sensitive adhesive layer has a discolored portion that is discolored by an external stimulus,
The layered product, wherein the oxygen barrier layer has an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. According to claim 1,
The pressure-sensitive adhesive layer includes an adhesive composition,
Wherein the adhesive composition contains a leuco-based pigment and a photo-acid generator. According to claim 1,
A laminate comprising an active energy ray blocking layer on one thickness direction of the oxygen barrier layer and/or on the other thickness direction of the oxygen barrier layer. A first step of disposing an adhesive layer on one side of the adherend in the thickness direction;
A second step of forming a discolored portion in the pressure-sensitive adhesive layer by an external stimulus;
A third step of disposing an oxygen barrier layer on one side of the pressure-sensitive adhesive layer in the thickness direction,
The method for producing a laminate according to claim 1, wherein the oxygen barrier layer has an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. An adhesive layer and an oxygen barrier layer are sequentially provided in the thickness direction,
The pressure-sensitive adhesive layer can be discolored by an external stimulus,
The variable color pressure-sensitive adhesive sheet, wherein the oxygen barrier layer has an oxygen transmission rate of 200 cm ³ /m ² ·day·atm or less. According to claim 5,
The variable color pressure-sensitive adhesive sheet, wherein the oxygen barrier layer is disposed directly on one side of the pressure-sensitive adhesive layer in the thickness direction. According to claim 5,
A variable color pressure-sensitive adhesive sheet further comprising an active energy ray blocking layer.

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