JP2022166714A - Laminate and article - Google Patents

Abstract

To provide a laminate which is prevented from deformation under pressure and has excellent designability.SOLUTION: A laminate comprises a first adhesive layer, a first substrate, a second adhesive layer, and a second substrate in this order. The second adhesive layer is composed of a colored adhesive. The laminate has an optical functional layer on at least one surface of the first substrate. The laminate has a printed layer at least in a part between the first adhesive layer and the first substrate or the optical functional layer.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a laminate and an article obtained by bonding the laminate to a transparent molding.

After producing a decorative laminated film in an integrated line using a roll-to-roll process, the decorative laminated film is cut to any size of a transparent molded body and pasted together, enabling inexpensive decoration of any size. Providing a film has been studied, and the development of an adhesive patch in which a decorative film and a transparent molding are laminated is underway.

For example, Patent Document 1 describes a cover glass suitable as a front substrate for a display or a white back cover glass, in which a white decorative region is formed on the outer edge portion of the surface of a transparent glass plate, and includes titanium oxide. A cover glass is described in which a resin film such as a white polyethylene terephthalate film contained is fixed to a glass plate via an adhesive layer. A white resin film that improves the whiteness of the cover glass is being studied.

JP 2015-145074 A

While decorative films are inexpensive and easy to increase in area, they have the problem of being vulnerable to pressure deformation. For example, after affixing a decorative film to a transparent member, the decorative film is vulnerable to the impact of contact from the decorative film side or when other members are pressed against it, and the decorative film is easily deformed. There has been a problem that the appearance of the decorated film is deteriorated.

As a countermeasure for this problem, if the thickness of the film constituting the decorative film is increased, the deformation due to pressure can be improved.
In addition, conventional decorative films can only express a single hue and cannot express multiple color designs with a single film, so multiple films are used to express multiple color designs. In addition, it is necessary to perform printing separately, and there are problems such as thinning and miniaturization of the article and an increase in cost due to an increase in the number of processes.
However, in recent years, there is a demand for a decorative film that can be made thinner, can be used easily, and has a rich design. .

Therefore, there has been a demand for a decorative film that suppresses deformation due to pressure and that is excellent in designability and that can impart a design of a plurality of colors with a single film.

The present invention has been made in view of the above, and an object thereof is to provide a laminate that suppresses deformation due to pressure and has excellent design.

The present inventors have made intensive studies to solve the above problems, and as a result, have found that a multi-color design can be easily expressed by providing a colored pressure-sensitive adhesive layer and a printed layer on a laminate. . Then, a first adhesive layer, a first substrate, a second adhesive layer, and a second substrate are provided in this order, the second adhesive layer is a colored adhesive, and at least one of the first substrates By forming a laminate having an optical functional layer on the surface and a printed layer at least partially between the first adhesive layer and the first substrate or optical functional layer, deformation due to pressure is suppressed However, the present inventors have found that a laminate having excellent design properties can be obtained, and have completed the present invention.

The present invention has the following configurations.
[1]
A first pressure-sensitive adhesive layer, a first substrate, a second pressure-sensitive adhesive layer, and a second substrate provided in this order,
The second adhesive layer is made of a colored adhesive,
having an optical functional layer on at least one surface of the first substrate;
A laminate having a printed layer at least partly between the first pressure-sensitive adhesive layer and the first substrate or the optical functional layer.
[2]
The laminate according to [1], wherein the optical function layer is a high refractive index layer.
[3]
The laminate according to [2], wherein the high refractive index layer contains at least one selected from NbOx, SiNx, and _TiO2 .
[4]
The laminate according to any one of [1] to [3], wherein the first adhesive layer has a thickness of 15 μm or more.
[5]
The laminate according to any one of [1] to [4], wherein the second substrate is a light diffusion layer.
[6]
The laminate according to [5], wherein the light diffusion layer contains zinc oxide particles or titanium oxide particles.
[7]
An article obtained by bonding the laminate according to any one of [1] to [6] to a transparent molding.

ADVANTAGE OF THE INVENTION According to this invention, the deformation|transformation with respect to a press can be suppressed and the laminated body excellent in design property can be provided.

FIG. 1 is a schematic cross-sectional view of a laminate according to one embodiment of the invention. FIG. 2 is a schematic cross-sectional view of a laminate according to one embodiment of the invention. FIG. 3 is a schematic cross-sectional view for explaining a method of manufacturing a laminate according to one embodiment of the present invention. FIG. 4 is a schematic cross-sectional view for explaining a method of manufacturing a laminate according to one embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of an article in which a laminate according to one embodiment of the present invention is attached to a transparent member. FIG. 6 is a schematic cross-sectional view of a laminate of a comparative example.

One preferred embodiment of the present invention will be described below with reference to the accompanying drawings. In the following, only preferred embodiments of the present invention are shown for convenience of explanation, but of course, this is not intended to limit the present invention.
In the following description, a numerical range represented using "-" means a range including the numerical values described before and after "-" as lower and upper limits.

[Laminate]
A laminate according to an embodiment of the present invention comprises a first adhesive layer, a first substrate, a second adhesive layer, and a second substrate in this order,
The second adhesive layer is made of a colored adhesive,
having an optical functional layer on at least one surface of the first substrate;
A printed layer is provided at least partly between the first pressure-sensitive adhesive layer and the first substrate or the optical functional layer.

The laminate of the present embodiment can be used by attaching the surface of the first pressure-sensitive adhesive layer opposite to the first substrate to, for example, a member such as a transparent molded article.
In the laminate of the present embodiment, the printed layer is provided at least partly between the first adhesive layer and the first substrate or the optical functional layer, thereby forming the laminate as the first adhesive. When viewed from the layer 15 side, the printed layer is positioned closer to the viewing side than the second adhesive layer (colored adhesive layer) made of colored adhesive, so the printed layer is not affected by the color of the colored adhesive layer. Therefore, the printed layer is easily visible, and the laminate can be provided with an excellent appearance in multiple colors, which is excellent in design.
In addition, since the laminate 1 of the present embodiment has the optical function layer on at least one surface of the first substrate, the second pressure-sensitive adhesive layer absorbs pressure due to contact or the like from the second substrate side. , deformation due to pressing can be suppressed.

FIG. 1 shows a schematic cross-sectional view of a laminate according to one embodiment of the present invention.

The laminate 1 according to the embodiment of the present invention must have an optical function layer on at least one surface of the first substrate, and as shown in FIG. You may have between two adhesive layers 13. In addition, the laminate 1 according to the embodiment of the present invention must have a print layer at least partly between the first adhesive layer and the first substrate or optical function layer, as shown in FIG. , the printed layer 16 may be provided at least partly between the first pressure-sensitive adhesive layer and the first substrate 14 .

In FIG. 1, the laminate 1 includes a first adhesive layer 15, a first substrate 14, an optical function layer 12, a second adhesive layer 13, and a second substrate 11 in this order. A printed layer 16 is provided at least partially between the substrate 14 and the first pressure-sensitive adhesive layer 15 .
According to this configuration, since the printed layer 16 is formed on the first substrate 14, there is an advantage that adhesion can be ensured by using a substrate that is compatible with the base material of the printed layer.

The laminate 1 according to the embodiment of the present invention must have an optical function layer on at least one surface of the first substrate, and as shown in FIG. It may be provided between one pressure-sensitive adhesive layer 15 . In addition, the laminate 1 according to the embodiment of the present invention must have a print layer at least partly between the first adhesive layer and the first substrate or optical function layer, as shown in FIG. , the printed layer 16 may be provided at least partly between the first pressure-sensitive adhesive layer and the optical function layer 12 .

In FIG. 2, the laminate 1 includes a first pressure-sensitive adhesive layer 15, an optical function layer 12, a first substrate 14, a second pressure-sensitive adhesive layer 13, and a second substrate 11 in this order. A printed layer 16 is partly provided between the pressure-sensitive adhesive layer 15 and the optical function layer 12 .
According to this configuration, since the print layer 16 is formed on the optical function layer 12, there is an advantage that adhesion can be ensured by using an optical function layer that is compatible with the base material of the print layer.

<First Substrate>
In the laminate according to this embodiment, examples of the material forming the first substrate 14 include resin, glass, and ceramics from the viewpoint of radio wave transmission.
The first substrate 14 is preferably transparent, and may be a substrate film, a resin molding substrate, a glass substrate, or an article to be decorated, preferably a substrate film. .
More specifically, the base film includes, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, polyamide, polyvinyl chloride, polycarbonate (PC), cycloolefin polymer (COP), polystyrene , polypropylene (PP), polyethylene, polycycloolefin, polyurethane, acrylic (PMMA), ABS, and other homopolymers or copolymers.

These base films are transparent, have little optical absorption, and do not affect brightness and visibility. However, from the viewpoint of forming various layers on the first substrate 14 later, it is preferable that the material can withstand high temperatures such as vapor deposition and sputtering. , acrylic, polycarbonate, cycloolefin polymer, ABS, polypropylene, polyurethane are preferred. Among them, polyethylene terephthalate, cycloolefin polymer, polycarbonate, and acrylic are preferable because they have a good balance between heat resistance and cost.

The base film may be a single layer film or a laminated film.
The thickness is preferably, for example, about 6 μm to 250 μm from the viewpoint of ease of processing. The lower limit of thickness is more preferably 15 μm or more. Also, the upper limit of the thickness is more preferably 200 μm or less, and still more preferably 150 μm or less. In addition, in order to strengthen the adhesive force with the layer formed on the base film, plasma treatment, easy-adhesion treatment, or the like may be performed.

A smooth or antiglare hard coat layer may be formed on the base film, if necessary. By providing the hard coat layer, the abrasion resistance can be improved. By providing the smooth hard coat layer, it is possible to enhance the design and prevent glare caused by the anti-glare hard coat layer. The hard coat layer can be formed by applying a solution containing a curable resin.

Examples of the curable resin include thermosetting resin, ultraviolet curable resin, electron beam curable resin, and the like. Types of curable resins include polyester, acrylic, urethane, acrylic urethane, amide, silicone, silicate, epoxy, melamine, oxetane, and acrylic urethane resins. One or more of these curable resins can be appropriately selected and used. Among these resins, acrylic resins, acrylic urethane resins, and epoxy resins are preferable because they have high hardness, can be cured with ultraviolet rays, and are excellent in productivity.

The thickness of the base film is, for example, 23 μm or more, preferably 50 μm or more, and from the viewpoint of productivity, it is, for example, 250 μm or less, preferably 150 μm or less. The thickness of the substrate can be measured using, for example, a film thickness meter (dial gauge).

The first adhesive layer 15 can be formed on the first substrate 14, may be formed on a part of the surface of the first substrate 14, or can be formed on the entire surface of the first substrate 14. You may

<First adhesive layer>
The first adhesive that forms the first adhesive layer 15 preferably has an elastic modulus of 1.0×10 ⁵ Pa or more at 25° C. Examples include acrylic adhesives, rubber adhesives, and silicone adhesives. Any one of adhesives, polyester-based adhesives, urethane-based adhesives, epoxy-based adhesives, and polyether-based adhesives can be used alone, or two or more of them can be used in combination. From the viewpoint of transparency, workability, durability, etc., it is preferable to use an acrylic pressure-sensitive adhesive.

The first pressure-sensitive adhesive layer 15 is preferably protected by a release liner until it is attached to an adherend.

The first pressure-sensitive adhesive layer is preferably formed from a first pressure-sensitive adhesive composition containing a base polymer (hereinafter sometimes simply referred to as "pressure-sensitive adhesive composition"). As the base polymer, it is possible to use a known polymer used for pressure-sensitive adhesives. Here, the base polymer refers to the main component of the polymer contained in the first pressure-sensitive adhesive composition. In this specification, the term "main component" refers to a component contained in an amount exceeding 50% by mass, unless otherwise specified.

(1-1) First PSA Composition The first PSA composition preferably contains a (meth)acrylic polymer as a base polymer. (Meth)acrylate refers to acrylate and/or methacrylate.

The (meth)acrylic polymer in the embodiment of the present invention is preferably a hydroxyl group-containing (meth)acrylic polymer containing alkyl (meth)acrylate and a hydroxyl group-containing monomer as monomer units. Although the method for introducing hydroxyl groups is not particularly limited, for example, a method of copolymerizing hydroxyl group-containing monomers can be easily carried out.

Incidentally, (meth)acrylic polymer in the embodiment of the present invention refers to acrylic polymer and/or methacrylic polymer, (meth)acrylate refers to acrylate and/or methacrylate, and alkyl (meth)acrylate refers to alkyl acrylates and/or alkyl methacrylates.

Examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and the like. is mentioned. These compounds may be used alone or in combination of two or more.

Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl ( meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)methyl acrylate, N-methylol (meth)acrylamide, N-hydroxy (meth)acrylamide, vinyl alcohol, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether and the like. These monomers may be used alone or in combination of two or more.

The hydroxyl group-containing monomer may be used alone or in combination of two or more. It is preferably 10 parts by mass, more preferably 2 to 6 parts by mass. By copolymerizing a hydroxyl group-containing monomer, a hydroxyl group-containing (meth)acrylic polymer to which reaction points are imparted by cross-linking or the like is obtained.

The (meth)acrylic polymer used in the embodiment of the present invention preferably has a weight average molecular weight of about 300,000 to 2,500,000. When the weight-average molecular weight is less than 300,000, the cohesive force of the pressure-sensitive adhesive composition tends to be low, resulting in adhesive residue. The weight-average molecular weight is obtained by measuring by GPC (gel permeation chromatography).

In addition, the (meth)acrylic polymer preferably has a glass transition temperature (Tg) of 0° C. or lower (usually −100° C. or higher), preferably −10° C. or lower, because it is easy to balance adhesive properties. When the glass transition temperature is higher than 0°C, the polymer becomes difficult to flow. The glass transition temperature (Tg) of the (meth)acrylic polymer can be adjusted within the above range by appropriately changing the monomer components and composition ratio used.

In addition, other polymerizable monomers other than the above monomers may be polymerizable monomers for adjusting the glass transition point and peelability of the (meth)acrylic polymer within a range that does not impair the effects of the present invention. can.

Other polymerizable monomers used in (meth)acrylic polymers include, for example, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, cyano group-containing monomers, vinyl ester monomers, aromatic vinyl monomers, etc. Functionality improving components, acid anhydride group-containing monomers, amide group-containing monomers, amino group-containing monomers, epoxy group-containing monomers, N-acryloylmorpholine, vinyl ether monomers, etc. Ingredients can be used as appropriate. These monomer compounds may be used alone or in combination of two or more.

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

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl laurate.

Examples of the aromatic vinyl monomers include styrene, chlorostyrene, chloromethylstyrene and α-methylstyrene.

Examples of the amide group-containing monomer include acrylamide and diethylacrylamide.

Examples of the amino group-containing monomer include N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N-(meth)acryloylmorpholine, and alkylaminoalkyl (meth)acrylates. and esters.

Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate and allyl glycidyl ether.

Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether and the like.

In the embodiment of the present invention, the other polymerizable monomers may be used alone or in combination of two or more, but the total content is 100 (meth) acrylic polymer It is preferably from 0 to 300 parts by mass, more preferably from 0 to 150 parts by mass.

The method of polymerizing the (meth)acrylic polymer is not particularly limited, and examples thereof include active energy ray polymerization such as solution polymerization and UV polymerization, and various radical polymerizations such as bulk polymerization and emulsion polymerization. Further, the obtained copolymer may be any of random copolymer, block copolymer, graft copolymer and the like.

Any appropriate additive can be employed as additives such as a polymerization initiator, a chain transfer agent, and an emulsifier used for radical polymerization, as long as the effects of the present invention are not impaired.

Examples of polymerization solvents that can be used for solution polymerization include ethyl acetate and toluene. The polymerization solvent may be of only one type, or may be of two or more types.

The solution polymerization is carried out, for example, under a stream of inert gas such as nitrogen, adding a polymerization initiator, and generally at a temperature of about 50° C. to 70° C. under reaction conditions of about 5 hours to 30 hours.

As the polymerization initiator that can be used for solution polymerization, any appropriate thermal polymerization initiator can be adopted as long as the effects of the present invention are not impaired. Only one polymerization initiator may be used, or two or more polymerization initiators may be used. Such polymerization initiators include, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, 2,2'-azobis(2-methylpropionic acid) dimethyl, 4,4'-azobis-4-cyanovaleric 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, 2,2′-azobis(N,N′-dimethyleneisobutyramidine), 2, Azo initiators such as 2′-azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate (VA-057, manufactured by Wako Pure Chemical Industries, Ltd.); potassium persulfate, ammonium persulfate, etc. persulfate of, di(2-ethylhexyl)peroxydicarbonate, di(4-t-butylcyclohexyl)peroxydicarbonate, di-sec-butylperoxydicarbonate, t-butyl peroxyneodecanoate, t-hexyl peroxypivalate, t-butyl peroxypivalate, dilauroyl peroxide, di-n-octanoyl peroxide, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate , di(4-methylbenzoyl) peroxide, dibenzoyl peroxide, t-butylperoxyisobutyrate, 1,1-di(t-hexylperoxy)cyclohexane, t-butyl hydroperoxide, hydrogen peroxide, etc. peroxide-based initiators; redox-based initiators that combine peroxides and reducing agents, such as combinations of persulfate and sodium hydrogen sulfite, and combinations of peroxides and sodium ascorbate;

The amount of the polymerization initiator to be used is preferably 1 part by mass or less, more preferably 0.005 parts per 100 parts by mass of the total amount of the monomer components, in order to allow the polymerization reaction to proceed effectively. The amount is from 0.01 to 0.7 parts by mass, preferably from 0.02 to 0.5 parts by mass.

As the chain transfer agent, any suitable chain transfer agent can be adopted as long as the effects of the present invention are not impaired. Only one type of chain transfer agent may be used, or two or more types may be used. Examples of such chain transfer agents include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, α-thioglycerol, thioglycolic acid, 2-ethylhexyl thioglycolate, 2,3-dimercapto-1-propanol, and the like. is mentioned.

The amount of the chain transfer agent to be used is preferably 0.1 part by mass or less with respect to 100 parts by mass of the total amount of the monomer components, in order to allow the polymerization reaction to proceed effectively.

As the emulsifier, any appropriate emulsifier can be adopted as long as the effects of the present invention are not impaired. Only one emulsifier may be used, or two or more emulsifiers may be used. Examples of such emulsifiers include anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, ammonium polyoxyethylene alkyl ether sulfate, and sodium polyoxyethylene alkylphenyl ether sulfate; nonionic emulsifiers such as oxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene-polyoxypropylene block polymers;

From the viewpoint of polymerization stability and mechanical stability, the amount of the emulsifier used is preferably 5 parts by mass or less, more preferably 0.3 parts by mass to 5 parts by mass, with respect to 100 parts by mass of the total amount of the monomer components. parts by mass, more preferably 0.4 to 3 parts by mass, and particularly preferably 0.5 to 1 part by mass.

The acrylic polymer can be preferably produced by active energy ray polymerization such as UV polymerization and electron beam polymerization. Acrylic polymers are more preferably produced by UV polymerization.

When carrying out UV polymerization, preferably a photoinitiator is used.

As the photopolymerization initiator, any appropriate photopolymerization initiator can be employed as long as the effects of the present invention are not impaired. Only one type of photopolymerization initiator may be used, or two or more types may be used. Examples of such photopolymerization initiators include benzoin ether-based photopolymerization initiators, acetophenone-based photopolymerization initiators, α-ketol-based photopolymerization initiators, aromatic sulfonyl chloride-based photopolymerization initiators, and photoactive oxime-based photopolymerization initiators. Photoinitiators, benzoin photoinitiators, benzyl photoinitiators, benzophenone photoinitiators, ketal photoinitiators, thioxanthone photoinitiators, acylphosphine oxide photoinitiators, etc. is mentioned.

Specific examples of benzoin ether-based photopolymerization initiators include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethane- 1-one (commercially available, for example, trade name "Irgacure 651", manufactured by BASF), anisole methyl ether, and the like.

Specific examples of the acetophenone-based photopolymerization initiator include, for example, 1-hydroxycyclohexylphenyl ketone (commercially available products such as trade name "Irgacure 184" manufactured by BASF), 4-phenoxydichloroacetophenone, 4- t-butyl-dichloroacetophenone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one (commercially available, for example, trade name "Irgacure 2959 ”, manufactured by BASF), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (commercially available products include, for example, trade name “Darocure 1173”, manufactured by BASF), methoxyacetophenone, and the like. .

Specific examples of α-ketol photopolymerization initiators include 2-methyl-2-hydroxypropiophenone, 1-[4-(2-hydroxyethyl)-phenyl]-2-hydroxy-2- and methylpropan-1-one.

Specific examples of aromatic sulfonyl chloride photopolymerization initiators include 2-naphthalenesulfonyl chloride.

Specific examples of photoactive oxime photopolymerization initiators include 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime.

Specific examples of benzoin-based photopolymerization initiators include benzoin.

Specific examples of benzyl-based photopolymerization initiators include benzyl.

Specific examples of benzophenone-based photopolymerization initiators include benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, and α-hydroxycyclohexylphenyl ketone.

Specific examples of ketal-based photopolymerization initiators include benzyl dimethyl ketal.

Specific examples of thioxanthone-based photopolymerization initiators include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, and 2,4-diethyl thioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, dodecylthioxanthone, and the like.

Specific examples of acylphosphine-based photopolymerization initiators include bis(2,6-dimethoxybenzoyl)phenylphosphine oxide and bis(2,6-dimethoxybenzoyl)(2,4,4-trimethylpentyl). Phosphine oxide, bis(2,6-dimethoxybenzoyl)-n-butylphosphine oxide, bis(2,6-dimethoxybenzoyl)-(2-methylpropan-1-yl)phosphine oxide, bis(2,6-dimethoxybenzoyl) )-(1-methylpropan-1-yl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-t-butylphosphine oxide, bis(2,6-dimethoxybenzoyl)cyclohexylphosphine oxide, bis(2,6- dimethoxybenzoyl)octylphosphine oxide, bis(2-methoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2-methoxybenzoyl)(1-methylpropan-1-yl)phosphine oxide, bis(2 ,6-diethoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2,6-diethoxybenzoyl)(1-methylpropan-1-yl)phosphine oxide, bis(2,6-di butoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2,4-dimethoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2,4,6-trimethylbenzoyl) ( 2,4-dipentoxyphenyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)benzylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylpropylphosphine oxide, bis(2,6-dimethoxybenzoyl) )-2-phenylethylphosphine oxide, bis(2,6-dimethoxybenzoyl)benzylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylpropylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2 -phenylethylphosphine oxide, 2,6-dimethoxybenzoylbenzylbutylphosphine oxide, 2,6-dimethoxybenzoylbenzyloctylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diisopropylphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl)-2-methylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-4-methylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diethylphenylphosphine oxide, bis(2,4,6- trimethylbenzoyl)-2,3,5,6-tetramethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,4-di-n-butoxyphenylphosphine oxide, 2,4,6-trimethyl Benzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)isobutylphosphine oxide, 2,6-dimethoxybenzoyl-2 ,4,6-trimethylbenzoyl-n-butylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,4-dibutoxyphenylphosphine oxide , 1,10-bis[bis(2,4,6-trimethylbenzoyl)phosphine oxide]decane, tri(2-methylbenzoyl)phosphine oxide and the like.

The amount of the photopolymerization initiator used is preferably 5 parts by mass or less, more preferably 0.01 parts by mass, with respect to 100 parts by mass of the total amount of the monomer components, from the viewpoint of expressing good polymerizability. parts to 5 parts by mass, more preferably 0.05 to 3 parts by mass, particularly preferably 0.05 to 1.5 parts by mass, and most preferably 0.1 to 1 part by mass. part by mass.

When carrying out UV polymerization, preferably polyfunctional (meth)acrylates are used.

Any appropriate polyfunctional (meth)acrylate can be employed as the polyfunctional (meth)acrylate as long as the effects of the present invention are not impaired. Only one kind of polyfunctional (meth)acrylate may be used, or two or more kinds thereof may be used. Specific examples of such polyfunctional (meth)acrylates include, for example, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, Pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2-ethylene glycol di(meth)acrylate, 1,6- Polyhydric alcohol such as hexanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate and (meth)acrylic acid vinyl (meth)acrylate; divinylbenzene; epoxy acrylate; polyester acrylate; urethane acrylate; butyl di(meth)acrylate; hexyl di(meth)acrylate;

The amount of the polyfunctional (meth)acrylate used is preferably 5 parts by mass or less, more preferably 0.1 part by mass, based on 100 parts by mass of the total amount of the monomer components, from the viewpoint of exhibiting good crosslinkability. 01 parts by mass to 5 parts by mass, more preferably 0.05 parts by mass to 3 parts by mass, particularly preferably 0.05 parts by mass to 1.5 parts by mass, most preferably 0.1 parts by mass ~1 part by mass.

Any appropriate UV polymerization method can be adopted as long as the effects of the present invention are not impaired. As a method of such UV polymerization, for example, a photopolymerization initiator and, if necessary, a polyfunctional (meth)acrylate are blended with the monomer component, and the mixture is irradiated with ultraviolet rays.

In the embodiment of the present invention, it is preferable to use an isocyanate-based cross-linking agent as the cross-linking agent. An isocyanate-based cross-linking agent is used to impart adhesion and cohesiveness.

Polyfunctional isocyanate compounds are used as isocyanate cross-linking agents, and include various compounds having two or more isocyanate groups in the molecule.

Examples of isocyanate compounds include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate; 2,4-tolylene diisocyanate; Aromatic isocyanates such as 4,4'-diphenylmethane diisocyanate and xylylene diisocyanate, trimethylolpropane/tolylene diisocyanate trimer adduct (trade name: Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane/hexamethylene Isocyanate adducts such as diisocyanate trimer adduct (trade name Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.) and isocyanurate of hexamethylene diisocyanate (trade name Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.). Among them, those having an isocyanurate ring are particularly preferred, for example, a polyisocyanate having a long-chain alkylenediol-modified isocyanurate ring (manufactured by Dainippon Ink and Chemicals, Barnock DN-995), an isocyanurate of hexamethylene diisocyanate. (trade name: Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.). These compounds may be used alone or in combination.

The content of the cross-linking agent used in the embodiment of the present invention may be blended to the extent that it does not affect the adhesive physical properties, but it is usually 0.2 to 10 parts by mass with respect to 100 parts by mass of the (meth)acrylic polymer. It is preferably contained in an amount of 0.5 to 8 parts by mass, more preferably 1 to 6 parts by mass.

The acrylic pressure-sensitive adhesives include powders such as cross-linking agents (polyamine compounds, melamine resins, aziridine derivatives, urea resins) other than those exemplified above, tackifiers, plasticizers, silane coupling agents, colorants, and pigments. , Dyes, Surfactants, Surface Lubricants, Leveling Agents, Softeners, Antioxidants, Antistatic Agents, Antiaging Agents, Light Stabilizers, UV Absorbers, Polymerization Inhibitors, Inorganic or Organic Fillers, Metal Powders , particles, foils and the like can be used as appropriate. These components may be used alone or in combination of two or more.

(1-2) Method for Forming First Adhesive Layer A laminate according to an embodiment of the present invention comprises a first adhesive layer, a first substrate, a second adhesive layer, and a second substrate. Prepare in this order. Moreover, it has a printed layer at least partly between the first substrate and the first pressure-sensitive adhesive layer or the second pressure-sensitive adhesive layer.
The first adhesive layer is, for example, after providing a printed layer on at least a part of the first substrate, on the surface provided with the printed layer, or on the surface opposite to the surface provided with the printed layer, the above adhesive It may be formed by laminating the pressure-sensitive adhesive layer side surface of the laminate of the pressure-sensitive adhesive layer formed from the composition and the release film.
Further, the first pressure-sensitive adhesive layer, for example, after providing a printed layer on at least a part of the first substrate, on the surface provided with the printed layer, or on the surface opposite to the surface provided with the printed layer, the above-mentioned It can also be formed by coating the adhesive composition on the transparent inorganic layer and removing the solvent and the like by drying. In applying the pressure-sensitive adhesive composition, one or more solvents may be added as appropriate.

Various methods are used as a method for applying the first pressure-sensitive adhesive composition. Specifically, for example, roll coating, kiss roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, die coater, etc. A method such as an extrusion coating method can be used.

The heat drying temperature is preferably about 30°C to 200°C, more preferably 40°C to 180°C, and even more preferably 80°C to 160°C. By setting the heating temperature within the above range, a first pressure-sensitive adhesive layer having excellent adhesive properties can be obtained. An appropriate drying time can be adopted as appropriate. The drying time is preferably about 5 seconds to 20 minutes, more preferably 30 seconds to 10 minutes, even more preferably 1 minute to 8 minutes.

When the pressure-sensitive adhesive composition is an active energy ray-curable pressure-sensitive adhesive, the first pressure-sensitive adhesive layer can be formed by irradiation with an active energy ray such as ultraviolet rays. A high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a chemical light lamp, or the like can be used for ultraviolet irradiation.

The thickness of the first pressure-sensitive adhesive layer 15 is, for example, preferably 3 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more from the viewpoint of adhesive strength and productivity. For example, it is preferably 150 μm or less, more preferably 100 μm or less. The thickness of the first adhesive layer 15 can be measured using, for example, a film thickness meter (dial gauge).

<Second base>
In the laminate according to this embodiment, the second substrate 11 may be made of resin, glass, ceramics, or the like from the viewpoint of radio wave transmission.
Resin is preferably used as the material of the second substrate.
Examples of resins include polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate; (meth)acrylic resins (acrylic resins and/or methacrylic resins) such as polymethacrylate; , olefin resins such as cycloolefin polymers, for example, polycarbonate resins, polyethersulfone resins, polyarylate resins, melamine resins, polyamide resins, polyimide resins, cellulose resins, polystyrene resins, norbornene resins. These resins can be used alone or in combination of two or more.

From the viewpoint of heat resistance and mechanical properties, the resin is preferably a polyester resin, more preferably PET, and still more preferably white PET.

The second substrate may be a light diffusion layer. By using a light diffusion layer as the second substrate, a laminate having excellent diffuse reflection can be obtained.

The light diffusing layer may contain a resin (binder resin) and light diffusing particles. The light diffusing particles are preferably dispersed in the binder resin.

The refractive index of the binder resin is preferably 1.2 to 2.4, more preferably 1.4 to 2.0. By using a binder resin having such a refractive index, a light diffusion layer having excellent light diffusion properties can be obtained.

In one embodiment, the refractive index of the binder resin is preferably 1.4-1.6, more preferably 1.4-1.55. A binder resin having such a refractive index can be used, for example, in combination with light diffusing particles having voids. The refractive index of the light diffusing particles having voids is, for example, 1 to 1.4 (preferably 1 to 1.2).

In another embodiment, the binder resin preferably has a refractive index of 1.6 to 2.4, more preferably 1.6 to 2.0. A binder resin having such a refractive index can be used, for example, in combination with light diffusing particles.
The refractive index of the light diffusing particles is, for example, 1.2 to 2 (preferably 1.4 to 1.6). Within such a range, a light diffusion layer having excellent light diffusion properties can be obtained.

The absolute value of the difference between the refractive index of the binder resin and the refractive index of the light diffusing particles is preferably 0.02 to 0.7, more preferably 0.05 to 0.5. Within such a range, a light diffusion layer having excellent light diffusion properties can be obtained.

As the light diffusing particles, organic particles may be used, or inorganic particles may be used. Inorganic particles are preferably used.
Examples of organic particles include polymethyl methacrylate, polymethyl acrylate, acrylic-styrene copolymer, melamine, polycarbonate, polystyrene, polyvinyl chloride, benzoguanamine-melamine formaldehyde, silica and the like. Among them, polymethyl methacrylate is preferred.
Examples of inorganic particles include metal oxides and metal fluorides. Specific examples of metal oxides include zirconium oxide (zirconia) (refractive index: 2.19), aluminum oxide (refractive index: 1.56 to 2.62), and zinc oxide (refractive index: 1.9 to 2.62). 0), titanium oxide (refractive index: 2.49 to 2.74), and silicon oxide (refractive index: 1.25 to 1.46). Specific examples of metal fluorides include magnesium fluoride (refractive index: 1.37) and calcium fluoride (refractive index: 1.40 to 1.43).
The refractive index of the inorganic particles is preferably 1.40 or less or 1.60 or more, more preferably 1.40 or less or 1.70 to 2.80, and particularly preferably 1.40 or less or 2.80. 00 to 2.80.
In the laminate according to this embodiment, the second substrate is preferably a light diffusion layer, and the light diffusion layer preferably contains zinc oxide particles or titanium oxide particles. Specific examples of the second substrate include white PET and the like.

The number average particle size of the light diffusing particles is preferably 0.1 μm to 3 μm, more preferably 0.3 μm to 2 μm, even more preferably 0.3 μm to 1.5 μm, and even more preferably 0.5 μm to 1.5 μm. By using a laminate having a light diffusing layer containing such light diffusing particles, an article with excellent diffuse reflection can be obtained. In addition, in this specification, the average particle diameter of the light diffusing particles in the light diffusing layer is measured by observing the cross section of the light diffusing layer using a microscope.

When the light diffusing particles are particles having voids, the average void size diameter of the particles is preferably 0.1 μm to 3 μm, more preferably 0.3 μm to 2 μm, and still more preferably 0.3 μm. ~1.5 µm, more preferably 0.5 µm to 1.5 µm. By using a laminate having a light diffusing layer containing such light diffusing particles, an article excellent in diffuse reflection can be obtained. In addition, in this specification, the average void size diameter can be measured by observing the cross section of the light diffusion layer using a microscope.

The content of the light diffusing particles is preferably 1 part by mass to 60 parts by mass, more preferably 2 parts by mass to 50 parts by mass, and still more preferably 5 parts by mass with respect to 100 parts by mass of the resin binder. parts to 40 parts by mass.

The thickness of the second base material is, for example, 23 μm or more, preferably 50 μm or more from the viewpoint of pressure deformation resistance, and is, for example, 250 μm or less, preferably 150 μm or less from the viewpoint of productivity. The thickness of the second base material can be measured using, for example, a film thickness meter (dial gauge).

<Light-shielding layer>
On the surface of the second substrate 11 opposite to the second pressure-sensitive adhesive layer 13 side, a light-shielding layer having no visible light transmittance from the viewpoint of light-shielding properties to the member to which the laminate 1 is attached is provided. may be provided. By providing the light-shielding layer, for example, when the laminate 1 of the present embodiment is used to decorate the housing of an electronic device, it is possible to prevent the circuit inside the housing from being seen through the laminate 1. can.

The material of the light-shielding layer is not particularly limited. For example, it is possible to use the material exemplified as the material that can be used for the second base 11 described above by adding a dye, a pigment, or a dye to color it black or the like. .
Also, a light-shielding layer may be provided on the second substrate 11 by light-shielding printing or the like, or a light-shielding tape or a light-shielding film may be used.

<Optical function layer>
A laminate according to an embodiment of the present invention must include an optical function layer on at least one surface of the first substrate.
The optical functional layer 12 is preferably provided between the first substrate 14 and the second pressure-sensitive adhesive layer 13 from the viewpoint of influence on the printed layer 16 .
By providing the optical functional layer 12 between the first substrate 14 and the second pressure-sensitive adhesive layer 13, the back side of the printed layer 16 becomes the optical functional layer 12, so that the printed layer does not affect the hue. It has the advantage of affecting only the hue of the second substrate.
The optical function layer 12 is preferably a layer having optical characteristics, and may include a high refractive index layer or a metal layer. The material forming the optical function layer is not particularly limited, and may contain metal and resin.
By providing the optical function layer 12, the laminate 1 according to the embodiment of the present invention can be made into a decorative film excellent in designability by the action of specularly reflected light.

The optical function layer 12 is preferably a layer made of metal oxide and/or metal nitride. The metal elements contained in the metal oxides and metal nitrides referred to here include semimetal elements such as Si. Metal oxides and/or metal nitrides also include metal oxynitrides. Moreover, the metal oxide may be an oxide of a single metal element (single oxide) or an oxide of a plurality of metal elements (composite oxide). Similarly, the metal nitride may be a nitride of a single metal element (single nitride) or a nitride of a plurality of metal elements (composite nitride).
Examples of metal elements include Ce, Nb, Si, Sb, Ti, Ta, Zr, and Zn.

More specifically, the material of the optical function layer 12 is CeO ₂ (2.30), NbO (2.33), Nb ₂ O ₃ (2.15), Nb ₂ O ₅ (2.20). , _SiO2 (1.46), SiN (2.03), Sb2O3 ₍ 2.10), _{TiO2 (} 2.35), _{Ta2O5 (} 2.10), ZrO2 ₍ 2.05) ), ZnO (2.10), ZnS (2.30), and the like (the numerical values in parentheses of the above materials are refractive indices).
In particular, the optical function layer 12 preferably contains at least one selected from Nb, Si and Ti, and preferably contains at least one selected from NbOx, SiO ₂ and TiO ₂ .

The thickness of the optical function layer 12 is preferably 10 nm to 1000 nm. From the viewpoint of cost, it is more preferably 800 nm or less, and even more preferably 500 nm or less. From the viewpoint of color, the thickness is preferably 15 nm or more, more preferably 20 nm or more, and even more preferably 30 nm or more.
The thickness of the optical function layer 12 can be measured, for example, by exposing a cross section in the direction perpendicular to the surface (thickness direction) and using a transmission electron microscope.

The refractive index of the optical function layer 12 is preferably 1.9 or higher, more preferably 2.0 or higher. From the viewpoint of thickness controllability, the refractive index of the optical function layer 12 is preferably 3.5 or less, more preferably 3.0 or less.

Moreover, the optical function layer 12 preferably includes a high refractive index layer, and may be a laminate of layers having different refractive indexes, or may include a low refractive index layer and a high refractive index layer.
The low refractive index layer having a refractive index of about 1.35 to 1.55 preferably contains low refractive index materials such as silicon oxide and magnesium fluoride, and more preferably silicon oxide. In addition, the high refractive index layer having a refractive index of about 1.80 to 2.40 includes titanium oxide (TiO ₂ ), niobium oxide (NbOx), zirconium oxide, tin-doped indium oxide (ITO), and antimony-doped as high refractive index materials. It preferably contains tin oxide (ATO), silicon nitride (SiNx), etc., more preferably contains at least one selected from NbOx, SiNx, and _TiO2 , and more preferably contains NbOx.
In addition to the low refractive index layer and the high refractive index layer, a medium refractive index layer with a refractive index of about 1.50 to 1.85, for example, titanium oxide or a mixture of the above low refractive index material and high refractive index material A thin film made of (such as a mixture of titanium oxide and silicon oxide) may be formed.

Note that the laminate 1 may include a plurality of optical function layers 12 .
For example, some oxides, such as niobium oxide, are reduced when exposed to ultraviolet light while laminated with an adhesive. In order to prevent the reduction action, a layer of silicon oxide is further laminated as a protective layer. It's okay to be there.

<Second adhesive layer>
The laminate 1 according to the embodiment of the present invention, as shown in FIGS. 1 and 2, comprises a second adhesive layer 13 between a first substrate 14 and a second substrate. The second adhesive layer consists of a colored adhesive. The second pressure-sensitive adhesive layer can be given the same color or a different color as the printed layer, and by providing a second pressure-sensitive adhesive layer (colored pressure-sensitive adhesive layer) made of a colored pressure-sensitive adhesive, the embodiment of the present invention can be A plurality of colors can be applied to the laminated body 1, and the design is excellent.

Further, in the laminate 1 according to the embodiment of the present invention, since the printed layer 16 is provided at least partly between the first adhesive layer 15 and the first substrate 14 or the optical function layer 12, lamination When the surface of the body 1 on the side of the first adhesive layer is laminated to a transparent molded body to form an article, the printed layer 16 is more colored than the second adhesive layer 13 (colored adhesive layer). The position is close to the viewing side. In this case, the colored adhesive layer is visible only in the portion where the printed layer 16 is not provided. As a result, the boundary between the printed layer 16 and the colored adhesive becomes clear, and the printed layer 16 and the colored adhesive become clearly visible, respectively, so that fine designs can be expressed. When the printed layer 16 and the second pressure-sensitive adhesive layer 13 have different colors, a design using a plurality of colors can be expressed.

When the colored adhesive layer is closer to the viewing side than the printed layer 16, the colored adhesive layer and the printed layer 16 are superimposed and viewed, and the printed layer 16 cannot be clearly seen. In addition, the color of the printed layer 16 overlaps the color of the colored adhesive layer, and the color of the printed layer 16 is visually recognized as a different color, resulting in inferior design.

Normally, when a design colored with multiple colors is to be expressed, a decorative film is separately used for coloring, which increases the process and the overall thickness. However, according to the laminate 1 according to the embodiment of the present invention, it is possible to express a design colored with multiple colors without increasing the process and thickness.

Furthermore, since the laminate 1 according to the embodiment of the present invention has the colored pressure-sensitive adhesive layer between the second substrate and the first substrate or the optical adjustment layer, pressing from the side of the second substrate is applied to the second substrate. The second pressure-sensitive adhesive layer can absorb and suppress deformation of the optical function layer and the first substrate due to pressing.

The colored pressure-sensitive adhesive may be, for example, a colored pressure-sensitive adhesive that is commonly used, or may be formed from a colored pressure-sensitive adhesive composition obtained by coloring the first pressure-sensitive adhesive composition described above.
Although the method for coloring the adhesive is not particularly limited, it can be colored, for example, by adding a small amount of dye to the adhesive composition.

A release liner is preferably provided on the second pressure-sensitive adhesive layer in order to protect the second pressure-sensitive adhesive layer until it is attached to the transparent molded body.

The thickness of the second pressure-sensitive adhesive layer 13 is preferably 3 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more from the viewpoint of adhesive strength and productivity. , preferably 150 μm or less, more preferably 100 μm or less. The thickness of the second adhesive layer 13 can be measured using, for example, a film thickness meter (dial gauge).

A release liner is preferably provided on the second pressure-sensitive adhesive layer in order to protect the second pressure-sensitive adhesive layer until it is attached to the transparent molded body.

<Print layer>
The laminate 1 according to this embodiment includes a print layer at least partly between the first pressure-sensitive adhesive layer and the first substrate or optical function layer.
In the laminate 1 according to this embodiment, the printed layer is preferably in contact with the first adhesive layer. For example, as shown in FIG. You may have it in at least one part between the adhesive layers 15. Moreover, as shown in FIG. 2, the printed layer 16 may be provided at least partly between the optical function layer 12 and the first pressure-sensitive adhesive layer 15 .
Since the printed layer 16 is in contact with the first adhesive layer 15, the unevenness of the surface of the printed layer is filled with the adhesive layer, so that the unevenness of the surface becomes difficult to see and the design is improved.

The printed layer can be formed by commonly used screen printing, flexographic printing, gravure printing, offset printing, inkjet printing, laser printer, and the like. The ink used for the printing layer is usually based on a varnish made by dissolving pigments, oils, natural resins, synthetic resins, etc. things, etc. The hue of the ink used for the printed layer can be appropriately determined according to the use of the laminate.
The laminate 1 according to this embodiment has a printed layer 16 at least partially between the first substrate 14 and the first adhesive layer 15, and the printed layer 16 is the first adhesive layer 15. is preferably in contact with
The thickness of the printed layer is not particularly limited, but in order to form a uniform printed layer without rubbing or unevenness, the upper limit is preferably 20.0 μm, more preferably 15.0 μm. , the lower limit is preferably 0.1 μm, more preferably 0.5 μm.

<Other layers>
In addition to the above-described first pressure-sensitive adhesive layer, first substrate, second pressure-sensitive adhesive layer, print layer, and second substrate, the laminate of this embodiment includes: Other layers may be provided depending on the application. Other layers include a protective layer (scratch resistant layer) to improve durability such as moisture resistance and scratch resistance, a barrier layer (corrosion prevention layer), an easy adhesion layer, a hard coat layer, an antireflection layer, a light Examples include extraction layers and antiglare layers.

<Production of laminate>
An example of a method for manufacturing the laminate 1 according to this embodiment will be described.

A method for producing a laminate according to an embodiment of the present invention is not particularly limited, but preferably includes the following steps (I) to (IV).
(I) Step of forming an optical function layer on a first substrate to obtain a first laminate (II) Forming a printed layer on at least part of at least one surface of the first laminate, Step of forming a first adhesive layer on the surface of the laminate on which the printed layer is formed to obtain a second laminate (III) Opposite to the surface of the second laminate on the side of the first adhesive layer Step of forming a second adhesive layer on the side surface to obtain a third laminate (IV) The surface of the third laminate on the side of the second adhesive layer and the second substrate affixing process

(I) Step of forming an optical function layer on the first substrate to obtain a first laminate In forming the optical function layer 12 on the first substrate 14, for example, a method such as vacuum deposition or sputtering can be used. can be used.

(II) Forming a printed layer on at least a part of at least one surface of the first laminate, forming a first pressure-sensitive adhesive layer on the surface of the first laminate on which the printed layer is formed, and forming a second laminate Step of Obtaining Body The printed layer must be provided at least partly between the first pressure-sensitive adhesive layer and the first substrate or the optical functional layer.
For example, as shown in FIG. 1, when the laminate 1 according to the embodiment of the present invention has the optical function layer 12 between the first substrate 14 and the second pressure-sensitive adhesive layer 13, as shown in FIG. As shown, after forming the printed layer 16 on at least part of the surface of the first laminate on the side of the first substrate 14, the surface of the first substrate 14 on which the printed layer 16 is formed is subjected to the above method. A second laminate (laminate 4) may be obtained by forming the first pressure-sensitive adhesive layer 15 by the above.
Moreover, as shown in FIG. 2, when the laminate 1 according to the embodiment of the present invention has the optical function layer 12 between the first substrate 14 and the first pressure-sensitive adhesive layer 15, as shown in FIG. As shown, after forming the printed layer 16 on at least a part of the surface of the first laminate on the side of the optical function layer 12, the surface of the first substrate 14 on which the printed layer 16 is formed is subjected to the above-described method. A product having the first pressure-sensitive adhesive layer 15 formed thereon may be used as the second laminate (laminate 6).

The printed layer can be formed by the method described above.

In forming the first pressure-sensitive adhesive layer on the surface of the first laminate on which the printed layer is formed, for example, the first pressure-sensitive adhesive composition is applied onto the support, the solvent and the like are removed by drying, In addition, a cross-linking treatment may be performed as necessary to form an adhesive layer, and the first adhesive layer 15 may be transferred onto the surface of the first laminate on which the printed layer is formed. The first adhesive composition may be applied directly onto the printed layer formed surface of the laminate to form the first adhesive layer 15 .

When the first pressure-sensitive adhesive layer 15 is directly provided on the printed layer-formed surface of the first laminate, for example, the first pressure-sensitive adhesive composition is applied onto the first substrate 14, and a solvent or the like is applied. The first adhesive layer 15 can be formed by drying and removing. In applying the first pressure-sensitive adhesive composition, one or more solvents may be added as appropriate. Further, when the first pressure-sensitive adhesive composition is active energy ray-curable, a prepolymer is prepared by polymerizing a part of the first pressure-sensitive adhesive composition, and the surface on which the printed layer in the first laminate is formed The first pressure-sensitive adhesive layer can be formed by coating the adhesive layer on the surface and irradiating the coating layer with an active energy ray such as ultraviolet rays.

As the support, for example, a release-treated sheet can be used. A silicone release liner (separator) is preferably used as the release-treated sheet.

Various methods are used as a method for applying the first pressure-sensitive adhesive composition. Specifically, for example, roll coating, kiss roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, die coater, etc. A method such as an extrusion coating method can be used.

The heat drying temperature is preferably about 30°C to 200°C, more preferably 40°C to 180°C, and even more preferably 80°C to 160°C. By setting the heating temperature within the above range, a first pressure-sensitive adhesive layer having excellent adhesive properties can be obtained. An appropriate drying time can be adopted as appropriate. The drying time is preferably about 5 seconds to 20 minutes, more preferably 30 seconds to 10 minutes, even more preferably 1 minute to 8 minutes.

When the first pressure-sensitive adhesive composition is an active energy ray-curable pressure-sensitive adhesive, the first pressure-sensitive adhesive layer can be formed by irradiation with an active energy ray such as ultraviolet rays. A high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a chemical light lamp, or the like can be used for ultraviolet irradiation.

A release liner may be provided on the surface of the second laminate on the first pressure-sensitive adhesive layer 15 side to protect the first pressure-sensitive adhesive layer 15 until it is used.

(III) Step of forming a second pressure-sensitive adhesive layer on the surface of the second laminate opposite to the surface facing the first pressure-sensitive adhesive layer to obtain a third laminate In forming the second pressure-sensitive adhesive layer 13 on the surface opposite to the first pressure-sensitive adhesive layer side, for example, the second pressure-sensitive adhesive composition is applied onto the support, and a solvent or the like is applied. The second pressure-sensitive adhesive layer 13 is formed by removing by drying and, if necessary, performing a cross-linking treatment. The second pressure-sensitive adhesive layer 13 may be transferred, and the second pressure-sensitive adhesive composition is applied directly onto the surface of the second laminate opposite to the surface of the first pressure-sensitive adhesive layer side to form the second pressure-sensitive adhesive layer. Two adhesive layers 13 may be formed to obtain a third laminate.

When the second adhesive layer 13 is directly provided on the first adhesive layer side surface of the second laminate, for example, the second adhesive composition is applied to the first adhesive layer of the second laminate. The second pressure-sensitive adhesive layer 13 can be formed by coating the adhesive layer side surface and removing the solvent and the like by drying.
In applying the second pressure-sensitive adhesive composition, one or more solvents may be added as appropriate. Further, when the second pressure-sensitive adhesive composition is active energy ray-curable, a prepolymer obtained by polymerizing a part of the second pressure-sensitive adhesive composition is prepared and applied, and active energy such as ultraviolet rays is applied to the coating layer. A third laminate can be obtained by forming the second pressure-sensitive adhesive layer 13 by irradiating with rays.

A release liner may be provided on the surface of the third laminate on the second pressure-sensitive adhesive layer 13 side to protect the second pressure-sensitive adhesive layer 13 until it is used.

(IV) Step of adhering the second pressure-sensitive adhesive layer side surface of the third laminate to the third laminate As shown in FIG. When the functional layer 12 is provided between the first substrate 14 and the second adhesive layer 13, as shown in FIG. , and the surface of the optical function layer 12 side of the laminate 4 (second laminate) laminated with the optical function layer 12, and the second adhesive layer 13, and the second adhesive layer 13 side The laminate 1 shown in FIG. 1 may be formed by bonding the surface and the second substrate 11 together.
Further, the surface of the optical function layer 12 side of the laminate 4 (second laminate) in which the first adhesive layer 15, the print layer 16, the first substrate 14, and the optical function layer 12 are laminated, and the second A laminate (not shown) in which the second adhesive layer 13 is formed on the substrate 11 of the second adhesive layer 13 side is attached by bonding together, and the laminate 1 shown in FIG. may be formed.

As shown in FIG. 2, when the laminate 1 according to the embodiment of the present invention has the optical function layer 12 between the first substrate 14 and the first adhesive layer 15, as shown in FIG. In addition, the surface of the first substrate 14 side of the laminate 6 (second laminate) in which the first adhesive layer 15, the printing layer 16, the optical function layer 12, and the first substrate 14 are laminated, and the first The laminate 1 shown in FIG. 2 may be formed by bonding the two adhesive layers 13 together, and bonding the surface on the second adhesive layer 13 side and the second substrate 11 together.
In addition, the first adhesive layer 15, the printed layer 16, the optical function layer 12, and the laminate 6 (second laminate) in which the first substrate 14 is laminated, the surface on the first substrate 14 side, The surface of the second adhesive layer 13 side of the laminate (not shown) in which the second adhesive layer 13 is formed on the substrate 11 of No. 2 is attached by bonding together, and the laminate shown in FIG. 1 may be formed.

<Goods>
The article according to this embodiment is obtained by bonding the laminate according to this embodiment to a transparent molded body.
FIG. 5 is a schematic cross-sectional view of an article according to one embodiment of the invention. In the article 10, the laminate 1 having the configuration shown in FIG. 5 is attached to a transparent member 20 which is a transparent molded body. In FIG. 5, the laminate 1 is attached to the surface of the transparent member 20 on the opposite side (hereinafter also referred to as the inner side) from the visible side (hereinafter also referred to as the outer side) through the first adhesive layer 15. The printed layer 16 is visually recognized through the transparent member 20 and the first adhesive layer 15 . In addition, the second adhesive layer 13 is visible through the transparent member 20, the first adhesive layer 15 and the first substrate 14 in the portion where the printed layer 16 is not formed. That is, in the laminate 1 of the present embodiment, the printed layer 16 can be visually recognized without passing through the second adhesive layer 13, so that the printed layer 16 and the second adhesive layer 13 can be clearly visually recognized. became. In addition, since the article 10 of the present embodiment is obtained by attaching the laminate 1 to the inner side of the transparent member 20, the article 10 is less likely to be damaged. Moreover, the transparent member 20 can be decorated while keeping the texture of the transparent member 20 as it is.

As the transparent member, a member made of glass or plastic can be used from the viewpoint of transparency.

The thickness of the transparent member is appropriately selected according to its use, but is preferably 100 μm to 2000 μm.

Although the method of attaching the laminate 1 to the transparent member 20 is not particularly limited, it can be attached by vacuum forming, for example. Vacuum forming means that the laminate 1 is heated and softened while being stretched, the space on the side of the transparent member of the laminate 1 is decompressed, and the space on the opposite side is pressurized as necessary, thereby forming the laminate 1 on the surface of the transparent member. It is a method of laminating while molding along the three-dimensional shape of.
As for the laminate 1, the above description can be used as it is.

<Use of goods>
Applications of the laminate and articles of the present embodiment include, for example, electronic device housings, vehicle structural parts, vehicle-mounted goods, home appliance housings, structural parts, mechanical parts, various automotive parts, electronic Apparatus parts, household goods such as furniture and kitchen utensils, medical equipment, building material parts, other structural parts and exterior parts.
More specifically, electronic devices and home appliances include household appliances such as refrigerators, washing machines, vacuum cleaners, microwave ovens, air conditioners, lighting equipment, electric water heaters, televisions, clocks, ventilation fans, projectors, speakers, personal computers, and mobile phones. , smart phones, digital cameras, tablet PCs, portable music players, portable game machines, battery chargers, electronic information devices such as batteries, and the like.
For vehicles, instrument panels, console boxes, door knobs, door trims, shift levers, pedals, glove boxes, bumpers, bonnets, fenders, trunks, doors, roofs, pillars, seats, steering wheels, ECU boxes, electrical parts , engine peripheral parts, drive system/gear peripheral parts, intake/exhaust system parts, cooling system parts, etc.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.

(Press deformation resistance evaluation)
A jig was attached so that the compression load cell (ELM-10N) was in contact with the decorative film side of an article (sample) in which the laminate was laminated to a transparent molded body (transparent member: glass). The load applied to the decorative film was adjusted to 0.4 N while tightening the bolt attached to the jig.
Also, the load was measured by an amplifier (EZT) connected to the load cell.

(Appearance evaluation)
A light beam was applied from the transparent member side of an article in which the laminate was bonded to a transparent molded body (transparent member), and the presence or absence of pressure deformation was visually observed from the transparent member side and evaluated according to the following criteria.
O: No pressure deformation was observed, and no distortion was observed in the reflected light beam. ×: Pressure deformation was observed, and there was distortion in the reflected light beam.

[Example 1]
(Polymerization of prepolymer composition A)
57 parts of n-butyl acrylate (BA), 16 parts of cyclohexyl acrylate (CHA), 23 parts of 4-hydroxybutyl acrylate (4HBA), 7 parts of hydroxyethyl acrylate (HEA) as monomer components, trade name as photopolymerization initiator After incorporating 0.075 parts of "Irgacure 651" (manufactured by BASF) and 0.075 parts of the trade name "Irgacure 184" (manufactured by BASF), the monomer mixture was partially cured by exposing it to ultraviolet light under a nitrogen atmosphere. A prepolymer composition A (polymerization rate of about 10%) was obtained by photopolymerization.
(Preparation of adhesive composition A)
To 100 parts of the resulting prepolymer composition A, 0.14 parts of dipentaerythritol hexaacrylate (trade name "KAYARAD DPHA", manufactured by Nippon Kayaku Co., Ltd.), a silane coupling agent (trade name "KBM-403", Shin-Etsu Chemical Kogyo Co., Ltd.) was added and uniformly mixed to obtain an adhesive composition A. The gel fraction was 84%.

[Preparation of first adhesive layer]
A 75 μm-thick polyethylene terephthalate (PET) film ("Diafoil MRF75" manufactured by Mitsubishi Chemical) having a silicone-based release layer on the surface is used as a second release film (heavy release film), and the above-mentioned is applied on the second release film. A coating layer was formed by applying the pressure-sensitive adhesive composition A to a thickness of 20 μm. On this coating layer, a 75 μm thick PET film (“Diafoil MRE75” manufactured by Mitsubishi Chemical Co., Ltd.) having one side subjected to silicone release treatment was laminated as a first release film (light release film). From the side of the first release film, this laminate is irradiated with ultraviolet rays by a black light whose position is adjusted so that the irradiation intensity on the irradiated surface directly below the lamp is 5 mW/cm ² , and photocuring is performed, resulting in a 20 μm thick adhesive. A pressure-sensitive adhesive sheet 1 having an agent layer A (first pressure-sensitive adhesive layer) was obtained.

[Preparation of hard coat composition]
An ultraviolet curable urethane acrylate resin ("Aika Itron Z844-22HL" manufactured by Aica Kogyo Co., Ltd.) was dissolved in methyl isobutyl ketone to prepare a hard coat composition having a solid content of 25%.

[Preparation of base film with hard coat layer]
The hard coat composition was applied to one surface of a 50 μm-thick substrate film (polyethylene terephthalate substrate (PET) manufactured by Mitsubishi Chemical Corporation) as the first substrate and dried at 100° C. for 1 minute. After that, curing treatment was performed by irradiating ultraviolet rays to form a hard coat layer having a thickness of 1.5 μm, thereby obtaining a substrate film with a hard coat layer.

[Preparation of base film with optical function layer]
An Nb target (manufactured by Daido Steel Co., Ltd.) is attached to an AC sputtering device ₍ AC: 40 kHz), and sputtering is performed while introducing Ar gas and O gas to obtain the substrate film with a hard coat layer obtained above. ₅ layers of Nb ₂ O with a thickness of 60 nm were formed as an optical function layer on the hard coat layer.
A substrate film with an optical function layer was produced by the above method.

[Formation of printed layer]
Using a screen printer manufactured by Newlong Seimitsu Kogyo Co., Ltd. and an ink manufactured by Seiko Advance Co., Ltd., the surface of the base film with the optical function layer obtained above using a printing plate to have a thickness of 5 μm on which the optical function layer is formed. A laminate A was produced by forming a printed layer on a part of the surface on the opposite side.

The light release film of the pressure-sensitive adhesive sheet 1 prepared above was peeled off and laminated to the surface of the printed layer of the laminate A prepared above to prepare a laminate B (laminate 4 in FIG. 3).

[Preparation of Adhesive Sheet 2]
(Polymerization of prepolymer composition A)
57 parts of n-butyl acrylate (BA), 16 parts of cyclohexyl acrylate (CHA), 23 parts of 4-hydroxybutyl acrylate (4HBA), 7 parts of hydroxyethyl acrylate (HEA) as monomer components, trade name as photopolymerization initiator After incorporating 0.075 parts of "Irgacure 651" (manufactured by BASF) and 0.075 parts of the trade name "Irgacure 184" (manufactured by BASF), the monomer mixture was partially cured by exposing it to ultraviolet light under a nitrogen atmosphere. A prepolymer composition A (polymerization rate of about 10%) was obtained by photopolymerization.
(Preparation of colored adhesive composition B)
To 100 parts of the resulting prepolymer composition A, 0.14 parts of dipentaerythritol hexaacrylate (trade name "KAYARAD DPHA", manufactured by Nippon Kayaku Co., Ltd.), a silane coupling agent (trade name "KBM-403", Shin-Etsu Chemical Kogyo Co., Ltd.) 0.3 parts, dispersant (trade name “Ajisper PB821”, Ajinomoto Fine-Techno Co., Ltd.) 0.04 parts by mass, yellow pigment (trade name “Dalamar Yellow” manufactured by Oakwood Chemical) 0.21 parts by mass was added and uniformly mixed to obtain a colored pressure-sensitive adhesive composition B. The gel fraction was 84%.

(Preparation of Adhesive Sheet 2)
A 75 μm-thick polyethylene terephthalate (PET) film ("Diafoil MRF75" manufactured by Mitsubishi Chemical) having a silicone-based release layer on the surface is used as a second release film (heavy release film), and the above-mentioned is applied on the second release film. A coating layer was formed by applying the colored pressure-sensitive adhesive composition B to a thickness of 20 μm. A 75 μm-thick PET film (“Diafoil MRE75” manufactured by Mitsubishi Chemical Co., Ltd.) having one side subjected to silicone release treatment was laminated as a first release film (light release film) onto this coating layer. From the side of the first release film, this laminate is irradiated with ultraviolet rays by a black light whose position is adjusted so that the irradiation intensity on the irradiated surface directly below the lamp is 5 mW/cm ² , and photocuring is performed, resulting in a 20 μm thick adhesive. A pressure-sensitive adhesive sheet 2 having an agent layer B (second pressure-sensitive adhesive layer) was obtained.

<Production of laminate and article>
The surface of the pressure-sensitive adhesive sheet 2 prepared above from which the light release film has been removed is attached to the optical function layer side surface of the laminate B prepared above. A white polyethylene terephthalate film containing titanium oxide particles having a thickness of 38 μm (“Lumirror E-20” manufactured by Toray Industries, Inc.) was laminated to prepare a laminate of Example 1.

The heavy release film on the first pressure-sensitive adhesive layer side of the laminate of Example 1 was peeled off and attached to a transparent molded body (transparent member) to obtain an article of Example 1. Glass with a thickness of 1.3 mm was used as the transparent member. The specimen size is 45 mm x 50 mm.

The laminate according to the embodiment of the present invention can be used for various purposes, and the laminate is used as a decorative film and laminated to the transparent member 20 which is a transparent molded body via the first pressure-sensitive adhesive layer 15. can be used as a decorative member.

[Comparative Example 1]
Adhesive sheet 1 and a base film with a hard coat layer were prepared in the same manner as in Example 1, and a printed layer was formed on a base film having a thickness of 50 μm (polyethylene terephthalate base (PET) manufactured by Mitsubishi Chemical Corporation). A laminate C was produced.

The light release film of the pressure-sensitive adhesive sheet 1 prepared in the same manner as in Example 1 was peeled off, and laminated to the surface of the laminate C prepared above on which the printed layer was formed, to prepare a laminate D.

As a second substrate, a 38 μm thick white polyethylene terephthalate film containing titanium oxide particles (“Lumirror E-20” manufactured by Toray Industries, Inc.) was coated with the hard coat composition on one side and heated at 100° C. for 1 minute. Dried. Thereafter, a curing treatment was performed by irradiating ultraviolet rays to form a hard coat layer having a thickness of 1.5 μm, thereby obtaining a white polyethylene terephthalate film (white PET film) with a hard coat layer.

An Nb target (manufactured by Daido Steel Co., Ltd.) is attached to an AC sputtering device ₍ AC: 40 kHz), and sputtering is performed while introducing Ar gas and O gas to obtain a white PET film with a hard coat layer obtained above. Laminate E was obtained by depositing ₅ Nb ₂ O layers having a film thickness of 60 nm as an optical function layer on the hard coat layer.

The surface of the adhesive sheet 2 prepared in the same manner as in Example 1, from which the light release film was removed, was attached to the base film side surface of the laminate D prepared above. A laminate of Comparative Example 1 was produced by bonding the optical function layer side surface of the laminate E produced in .

An article of Comparative Example 1 was produced in the same manner as in Example 1 except that the laminate in Example 1 was changed to the laminate of Comparative Example 1.

Table 1 below shows the evaluation results.

As is clear from Table 1, in the laminate of Example 1, even when light is irradiated from the transparent member side of the article bonded to the transparent member, the reflected image is not distorted due to the displacement of the surface shape, and is good. Appearance is obtained.

On the other hand, in the laminate of Comparative Example 1, the reflected image was distorted due to the displacement of the surface shape, resulting in deterioration of the external appearance.

The present invention is not limited to the above embodiments, and can be embodied with appropriate modifications within the scope of the invention.

The laminate and article according to the present invention have an excellent appearance, and the decorative member provided with the laminate or article according to the present invention can be used for various devices, parts, and the like. For example, housings for electronic devices such as mobile phones, smartphones, and personal computers, structural parts for vehicles, articles mounted on vehicles, housings for home appliances, structural parts, machine parts, various automotive parts, electronic device parts, and furniture. , household goods such as kitchen utensils, medical equipment, building material parts, other structural parts and exterior parts, and various other applications that require design and cost reduction.

REFERENCE SIGNS LIST 1 laminate 10 article 11 second substrate 12 optical function layer 13 second pressure-sensitive adhesive layer 14 first substrate 15 first pressure-sensitive adhesive layer 16 printing layer

Claims (7)

A first pressure-sensitive adhesive layer, a first substrate, a second pressure-sensitive adhesive layer, and a second substrate provided in this order,
The second adhesive layer is made of a colored adhesive,
having an optical functional layer on at least one surface of the first substrate;
A laminate having a printed layer at least partly between the first pressure-sensitive adhesive layer and the first substrate or the optical functional layer. 2. The laminate according to claim 1, wherein the optical function layer is a high refractive index layer. 3. The laminate according to claim 2, wherein the high refractive index layer contains at least one selected from NbOx, SiNx, and _TiO2 . The laminate according to any one of claims 1 to 3, wherein the thickness of the first pressure-sensitive adhesive layer is 15 µm or more. 5. The laminate according to any one of claims 1 to 4, wherein said second substrate is a light diffusion layer. 6. The laminate according to claim 5, wherein the light diffusion layer contains zinc oxide particles or titanium oxide particles. An article obtained by bonding the laminate according to any one of claims 1 to 6 to a transparent molding.

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