KR20240037376A - Adhesive resin composition, adhesive sheet, active energy ray curable adhesive sheet, optical member, laminate for image display device and image display device - Google Patents

Abstract

Regarding the adhesive resin composition, the blending amount of the initiator and crosslinking agent can be reduced, and after crosslinking, the remaining amount of low molecular weight compounds such as the initiator and its decomposition products can be reduced, cohesion can be increased, and especially UV-resistant foaming reliability can be improved. Provides an adhesive resin composition that can increase the corrosion resistance of metals and has properties that do not promote corrosion of metals. (meth)acrylic polymer or (meth)acrylic copolymer (A) (referred to as “(meth)acrylic (co)polymer (A)”), a radical polymerizable functional group having a carbon-carbon double bond and a radical generator are contained within the molecule. An adhesive resin composition comprising a compound (B) and an initiator (C) made of a compound other than the compound (B).

Description

Adhesive resin composition, adhesive sheet, active energy ray-curable adhesive sheet, optical member, laminate for image display device, and image display device AND IMAGE DISPLAY DEVICE}

The present invention relates to a pressure-sensitive adhesive resin composition that can be suitably used for bonding members constituting an image display device, and an adhesive sheet formed from the pressure-sensitive adhesive resin composition, particularly, having active energy ray curability. It relates to a pre-curable adhesive sheet, an optical member, a laminate for an image display device, and an image display device.

Recently, in order to improve the visibility of image display devices, an image display panel such as a liquid crystal display (LCD), plasma display (PDP), or electroluminescence display (ELD), and a protection panel placed on the front side (viewer side) of the image display panel are used. It has been implemented to suppress reflection of incident light or emitted light from a display image at the air layer interface by filling the gap between the surface and the touch panel member with a pressure-sensitive adhesive sheet or liquid adhesive.

As a method of filling the voids between such structural members for an image display device using an adhesive, for example, in Patent Document 1, the voids are filled with a liquid photocurable adhesive resin composition containing an ultraviolet curable resin, A method of curing by irradiating ultraviolet rays is disclosed.

Additionally, a method of bonding structural members for an image display device together using an adhesive sheet is also known. For example, Patent Document 2 discloses a method for manufacturing a laminate for an image display device having a structure in which an image display device component is laminated on at least one side of a transparent double-sided adhesive sheet, which is first crosslinked by ultraviolet rays. A method is disclosed in which two image display device structural members are laminated through a chemical conversion adhesive sheet, and then the photocurable adhesive sheet is irradiated with ultraviolet rays through the image display device structural member to cause secondary crosslinking and curing.

Additionally, Patent Document 3 states that the temperature at which the maximum loss tangent (Tanδ) obtained by measuring dynamic viscoelasticity by a shear method is -20°C or higher, and that the weight average molecular weight is 50,000 to 800,000 acrylic copolymers 50 to 90. 10 to 50 masses of a polyfunctional (meth)acrylate monomer having a mass part and molecular weight of 700 or more and a temperature showing the maximum value of the loss tangent (Tanδ) obtained by dynamic viscoelasticity measurement using the shear method of homopolymers is less than 0°C and an active energy ray-curable adhesive composition, that is, a photocurable adhesive resin composition, including a hydrogen abstraction type photopolymerization initiator.

Additionally, Patent Document 4 discloses an ultraviolet crosslinkable pressure-sensitive adhesive sheet comprising a (meth)acrylic copolymer, which is a monomer containing a (meth)acrylic acid ester having an ultraviolet crosslinkable site, and the ultraviolet rays of the pressure-sensitive adhesive sheet. The storage elastic modulus before crosslinking is 5.0×10 ⁴ to 1.0×10 ⁶ Pa at 30°C and 1 Hz, and is 5.0×10 ⁴ Pa or less at 80°C and 1 Hz, and the ultraviolet ray crosslinking of the pressure-sensitive adhesive sheet It discloses an ultraviolet crosslinkable pressure-sensitive adhesive sheet, that is, a photocurable pressure-sensitive adhesive sheet, which has a post-storage elastic modulus of 1.0×10 ³ Pa or more at 130° C. and 1 Hz.

International Publication No. 2010/027041 Japanese Patent No. 4971529 Publication Japanese Patent Laid-Open No. 2008-248103 Japanese Patent Publication No. 2013-522393

With the recent trend of image display devices becoming thinner and lighter, image display components such as surface protection panels, which were conventionally made of glass materials, are being replaced with plastic materials such as acrylic and polycarbonate. And with the change in materials, new challenges are arising. For example, when a laminate of a plastic plate and a double-sided adhesive sheet is exposed to high temperature and high humidity conditions or is exposed to ultraviolet rays, outgass is generated from the plastic plate, causing bubbles, lifting, peeling, etc. A task is emerging.

In order to suppress such bubbles, lifting, and peeling, it is required to further increase the cohesive force of the adhesive sheet.

In addition, in image display devices equipped with a touch panel, for example, a touch panel and other structural members, such as a touch panel and a liquid crystal module, a touch panel and a surface protection panel, are integrated by bonding them together through an adhesive sheet.

However, it has been pointed out that the transparent conductive layer and conductor pattern provided in the touch panel are vulnerable to corrosion, and are easily corroded by outgassing from the adhesive sheet or acidic components derived from eluted components.

Among them, in the case of a pressure-sensitive adhesive resin composition with active energy ray curing (crosslinking) properties, the initiator is activated by irradiation with active energy rays, for example, light to generate radicals, and these radicals react with silver in the metal material, There is a risk of corrosion occurring.

Therefore, in particular, active energy ray-curable adhesive resin compositions are required to have the performance of not promoting metal corrosion.

Therefore, in the present invention, in order to further increase the cohesion of the adhesive sheet, especially the active energy ray-curable adhesive sheet as described above, the influence of the initiator and its decomposition products, etc., remaining after curing (crosslinking) was studied.

As a result, in the active energy ray-curable adhesive resin composition containing low molecular weight compounds such as an initiator and a crosslinking agent, if the initiator and its decomposition products, and further low molecular weight compounds such as a crosslinking agent, remain in the adhesive sheet after active energy ray curing, It was found that the cohesion of the adhesive sheet decreased and had a negative effect on heat-resistant foaming reliability, moist heat-resistant foaming reliability, and ultraviolet-resistant foaming reliability.

Additionally, if acidic components or halogens are contained in the residue after cleavage of an initiator or crosslinking agent, for example, a cleavage type initiator, and if they remain as low molecular weight compounds, these acidic components or halogens, for example, ITO or Cu. , it was also found to be a cause of corrosion of metal parts such as Ag.

Additionally, it was found that if a large amount of hydrogen abstraction type initiator or unreacted cleavage type initiator, etc. remains as a low molecular weight compound, radicals generated by light irradiation become a cause of corrosion of the metal.

Therefore, the present invention relates to an adhesive resin composition, particularly an adhesive resin composition having active energy ray curing properties. In order to reduce as much as possible the amount of low molecular weight compounds such as initiators and their decomposition products remaining after active energy ray curing, The amount of initiator and cross-linking agent can be reduced, and at the same time, the cohesion after curing with active energy rays can be sufficiently increased. In particular, the reliability of foaming against ultraviolet rays can be increased, and furthermore, it has the property of not promoting metal corrosion. The object is to provide an adhesive resin composition.

The present invention relates to a (meth)acrylic polymer or (meth)acrylic copolymer (A) (referred to as “(meth)acrylic (co)polymer (A)”), a radically polymerizable functional group and a radical having a carbon-carbon double bond. It relates to a pressure-sensitive adhesive resin composition comprising a compound (B) having a generative group in the molecule, and an initiator (C) made of a compound other than the compound (B).

The present invention further provides a combination of a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, and an initiator (C) consisting of a compound other than the compound (B), It relates to a method of using compound (B) as an initiator, characterized in that it is used by mixing with an acrylic (co)polymer (A).

The compound (B), which has a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, has both the property of functioning as a so-called initiator, which generates radicals by irradiation of active energy rays, and the property of a crosslinking agent. Since one compound can simultaneously serve as an initiator and a cross-linking agent, the amount of the initiator and the cross-linking agent used can be reduced.

However, when the compound (B) is actually used by mixing it with the (meth)acrylic (co)polymer (A), the compound (B) alone does not function as an initiator, or the function is significantly low. It became clear.

Additionally, when the compound (B) was used in combination with another initiator (C), particularly a cleavage type photoinitiator, it became clear that the compound (B) functioned as an initiator.

In addition, it was also found that the total content of the compound (B) and the initiator (C) can be made smaller than the total content of the initiator and crosslinking agent conventionally used in photocurable adhesive resin compositions.

Additionally, when the compound (B) and an initiator (C) made of a compound other than the compound (B) are combined and mixed with the (meth)acrylic (co)polymer (A), the compound (B) is: Due to the action of the initiator (C), the radically polymerizable functional group reacts to increase the molecular weight (acts as a crosslinking agent), so it does not remain as a low molecular weight compound, and the compound with which the radically polymerizable functional group reacted (acts as a crosslinking agent) Since B) also functions as an initiator, the content of initiator (C) can be suppressed to a very small amount.

Therefore, the amount of low molecular weight compounds in the system can be significantly suppressed, the cohesion of the pressure-sensitive adhesive resin composition can be increased, and the ultraviolet ray resistance foaming property can be improved.

In addition, since the adverse effect on the metal caused by the initiator is extremely reduced, it can be provided with the property of not promoting corrosion of the metal.

1 is a diagram for explaining the evaluation test method for ITO corrosion resistance and Cu corrosion resistance performed in the examples described later, and (A) is a top view or internal view of the ITO pattern of the ITO glass substrate. (B) is a top view of the copper pattern on a copper glass substrate for corrosion-resistant reliability evaluation, (B) is a top view showing an adhesive sheet covered on an ITO glass substrate for corrosion-resistant ITO corrosion reliability evaluation, or on a copper glass substrate for Cu-resistant corrosion reliability evaluation. A top view showing a state covered with an adhesive sheet, (C) is a cross-sectional view of a sample for evaluating ITO corrosion resistance reliability, and (D) is a cross-sectional view of a sample for evaluating Cu corrosion resistance reliability.
Figure 2 is a diagram for explaining a test method for evaluating Ag corrosion resistance reliability performed in an example described later.

Next, the present invention will be explained based on embodiment examples. However, the present invention is not limited to the embodiment described below.

<<This composition>>

The pressure-sensitive adhesive resin composition (also referred to as “this composition”) related to an example of an embodiment of the present invention includes a (meth)acrylic (co)polymer (A), a radically polymerizable functional group having a carbon-carbon double bond, and a radical generator. It contains a compound (B) having in the molecule, and an initiator (C) made of a compound other than the compound (B), and if necessary, further contains a rust inhibitor (D), a crosslinking agent (E), and other components. It is an adhesive resin composition.

The compound (B), which has a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, is a compound that can function as an initiator or a crosslinking agent, and generates a radical that initiates a polymerization reaction under excitation by an active energy ray. In addition to functioning as an initiator through the action of a radical generator, the compound (B) polymerizes with each other through a reaction with a radical polymerizable functional group, thereby also functioning as a crosslinking agent.

However, compound (B) does not function as an initiator alone, or its function is significantly low, but when used in combination with another initiator (C), it functions as an initiator.

That is, when the active radical species generated from the initiator (C) cleaves the carbon-carbon double bond of the compound (B), thereby polymerizing the compounds (B), a radical generator acts and also functions as an initiator.

In addition, in the present invention, “active energy ray” means an energy ray that can generate active species by decomposing a compound that generates active species. Such active energy rays include, for example, visible light, ultraviolet rays, infrared rays, Examples include X-rays, α-rays, β-rays, γ-rays, and electron rays. Among them, ultraviolet rays and electron beams are preferable.

As described above, in the present composition, the compounds (B) polymerize with each other to increase the molecular weight, so the production of low molecular weight compounds can be suppressed and the cohesion of the adhesive resin composition can be improved.

In addition, when the radical generator has a structure that generates radicals by generating a hydrogen abstraction reaction, a cross-linked structure can be formed between the (meth)acrylic copolymer (A) molecules, and cohesion can be further improved.

As described above, the compound (B) alone has no or significantly low function as an initiator and crosslinking agent, but when used in combination with an initiator (C) other than the compound (B), the compound (B) By cleaving the radical polymerizable functional group, both functions as an initiator and a crosslinking agent can be expressed.

Additionally, the mechanism of expression of the above function is inferred as follows.

The compound (B), which has both a radically polymerizable functional group having a carbon-carbon double bond and a radical generator, reduces the reactivity of the radical generator due to the influence of the π electrons possessed by the radically polymerizable functional group or its primary structure. It works in the direction you tell it to.

Therefore, an initiator (C) other than the compound (B) is used in combination, and the double bond of the radical polymerizable functional group of the compound (B) is reacted (cleaved) by the action of the initiator (C), resulting in the above-mentioned The effect of lowering the reactivity of the radical generator disappears, and the reaction by the radical generator proceeds.

In particular, when a compound having a (meth)acryloyl group and a benzophenone structure is used as the compound (B) as an example, the mechanism of action is explained in more detail, and it is inferred that it is as follows.

When the benzophenone structure, which is a radical generator, is irradiated with an active energy ray and brought into an excited state, the unpaired electron of the carbonyl group in the benzophenone structure is localized on the oxygen atom side, thereby improving the hydrogen extraction reactivity of the excited benzophenone structure. do.

However, as in the compound (B), if a (meth)acryloyl group having π electrons, which is a radically polymerizable functional group, is included in the same molecule, the deflection of the charge of the carbonyl group described above is suppressed due to its influence.

In other words, the compound (B) alone significantly reduces its function as an initiator of the benzophenone structure, that is, the radical reactivity due to hydrogen extraction.

On the other hand, when the double bond of the radically polymerizable functional group of the compound (B) is reacted (cleaved), the effect of lowering the reactivity described above is lost, so the hydrogen abstraction reactivity of the excited benzophenone structure of (B) is reduced. As this improves, the radical reaction due to hydrogen extraction progresses.

This composition not only increases the cohesive force due to the mechanism of action described above, but also prevents the compound (B) from remaining in a low molecular weight state, thereby suppressing a decrease in the cohesive force and providing excellent anti-foaming properties. Reliability can be achieved.

Additionally, the content of the initiator (C) can be suppressed, and the adverse effect on the metal due to the initiator is extremely reduced, so it can be provided with the property of not promoting corrosion of the metal.

Furthermore, the total content of the compound (B) and the initiator (C) can be made smaller than the total content of the initiator and crosslinking agent conventionally used in photocurable adhesive resin compositions.

<(meth)acrylic (co)polymer (A)>

As the (meth)acrylic (co)polymer (A), the formula 1 below (wherein R ₁ represents a hydrogen atom or a methyl group, and R ₂ is a straight chain or branched polymer having 4 to 18 carbon atoms ( It is preferable to contain 50% by mass or more of the structural unit represented by (represents an alkyl group of the fraction), the so-called monomer component.

Among them, the (meth)acrylic (co)polymer (A) more preferably contains 55% by mass or more of the monomer component, and particularly preferably contains 60% by mass or more.

In addition, in the present invention, “(meth)acrylic” refers to acrylic and methacrylic, “(meth)acryloyl” refers to acryloyl and methacryloyl, and “(meth)acrylate” refers to acrylic. It is meant to encompass rate and methacrylate, respectively, and “(co)polymer” is meant to encompass polymers and copolymers.

[Formula 1]

Examples of the monomer represented by Formula 1 include n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, and pentyl (meth)acrylate. Acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate , 2-ethylhexyl EO modified (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, t-butylcyclohexyl. (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate Acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, isobornyl (meth)acrylate, 3,5,5-trimethylcyclohexane (meth)acrylate , dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, etc. These may be used one type or in combination of two or more types. These can be used singly or in combination of two or more types. Among the above, it is particularly preferable to include at least one of butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and lauryl (meth)acrylate.

The (meth)acrylic (co)polymer (A) preferably has “another copolymerizable monomer” other than the monomer component as a copolymerization component.

The above-mentioned "other copolymerizable monomer" is preferably contained in the (meth)acrylic (co)polymer (A) in an amount of 1 to 30% by mass, and in particular, it is contained in a ratio of 2% by mass or more or 25% by mass or less. It is more desirable.

Examples of the “other copolymerizable monomer” include (a) a carboxyl group-containing monomer (hereinafter also referred to as “copolymerizable monomer A”), (b) a hydroxyl group-containing monomer (hereinafter also referred to as “copolymerizable monomer B”), (c) Amino group-containing monomer (hereinafter also referred to as “copolymerizable monomer C”), (d) epoxy group-containing monomer (hereinafter also referred to as “copolymerizable monomer D”), (e) amide group-containing monomer (hereinafter referred to as “copolymerizable monomer D”) (also referred to as “monomer E”), (f) vinyl monomer (hereinafter also referred to as “copolymerizable monomer F”), (g) (meth)acrylate monomer with a side chain having 1 to 3 carbon atoms (hereinafter referred to as “copolymerizable monomer G”) "), (h) macro monomer (hereinafter also referred to as "copolymerizable monomer H"), (i) aromatic-containing monomer (hereinafter referred to as "copolymerizable monomer I"), (j) containing other functional groups. and monomers (hereinafter “copolymerizable monomer J”). These can be used singly or in combination of two or more types.

Examples of the copolymerizable monomer A include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypropyl (meth)acrylate, carboxybutyl (meth)acrylate, and ω-carboxypolycaprolactone mono(meth)acrylic. Rate, 2-(meth)acryloyloxyethylhexahydrophthalic acid, 2-(meth)acryloyloxypropylhexahydrophthalic acid, 2-(meth)acryloyloxyethylphthalic acid, 2-(meth)acryloyl Oxypropylphthalic acid, 2-(meth)acryloyloxyethylmaleic acid, 2-(meth)acryloyloxypropylmaleic acid, 2-(meth)acryloyloxyethylsuccinic acid, 2-(meth)acryloyl Examples include oxypropylsuccinic acid, crotonic acid, fumaric acid, maleic acid, and itaconic acid. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer B include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate. ) Hydroxyalkyl (meth)acrylates such as acrylate can be mentioned. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer C include aminoalkyl (meth)acrylates such as aminomethyl (meth)acrylate, aminoethyl (meth)acrylate, aminopropyl (meth)acrylate, and aminoisopropyl (meth)acrylate. N,N-dialkylaminoalkyl (meth)acrylate, N-alkylaminoalkyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, etc. ) Acrylates can be mentioned. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer D include glycidyl (meth)acrylate, methylglycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. ) Acrylate glycidyl ether can be mentioned. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer E include (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-methylol(meth)acrylamide, and N-methylol. Propane (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide, diacetone (meth)acrylamide, maleic acid amide, and maleimide can be mentioned. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer F include compounds having a vinyl group in the molecule. Such compounds include (meth)acrylic acid alkyl esters in which the alkyl group has 1 to 12 carbon atoms, functional monomers having functional groups such as hydroxyl group, amide group, and alkoxyalkyl group in the molecule, and polyalkylene glycol di(meth) Acrylates, vinyl ester monomers such as vinyl acetate, N-vinyl-2-pyrrolidone, vinyl propionate, and vinyl laurate, and styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, and other substituted styrenes. An example may be an aromatic vinyl monomer. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer G include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and i-propyl (meth)acrylate. These may be used alone or in combination of two or more types.

The macromonomer as the copolymerizable monomer H is a polymer monomer having a terminal functional group and a high molecular weight skeleton component, and is preferably a monomer whose side chain has 20 or more carbon atoms when polymerized into a (meth)acrylic acid ester copolymer. .

By using the copolymerizable monomer H, a macromonomer can be introduced as a branch component of the graft copolymer, and the (meth)acrylic acid ester copolymer can be converted into a graft copolymer. For example, it can be a (meth)acrylic acid ester copolymer (a) made of a graft copolymer having a macromonomer as a branching component.

Therefore, the characteristics of the main chain and side chains of the graft copolymer can be changed by selection and mixing ratio of the copolymerizable monomer H and other monomers.

The skeleton component of the macromonomer is preferably composed of an acrylic acid ester polymer or a vinyl polymer. Examples include linear or branched alkyl (meth)acrylates having 4 to 18 carbon atoms in the side chain, copolymerizable monomer A, copolymer B, copolymer G, etc., which can be used alone. It can be used in combination or in combination of two or more types.

Examples of the copolymerizable monomer I include benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, and nonylphenol EO modified (meth)acrylate. Rates, etc. can be mentioned. These may be used alone or in combination of two or more types.

Examples of the copolymerizable monomer J include (meth)acrylic modified silicone, 2,2,2-trifluoroethyl (meth)acrylate, and 2,2,3,3-tetrafluoropropyl (meth)acrylate. Late, 2,2,3,3-tetrafluoropropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, 1H,1H,2H,2H-tridecafluoro-n -Fluorine-containing monomers such as octyl (meth)acrylate, etc. can be mentioned. These may be used alone or in combination of two or more types.

The (meth)acrylic (co)polymer (A) preferably does not contain or substantially does not contain the above-mentioned “copolymerizable monomer A” from the viewpoint of metal corrosion resistance and moist heat whitening resistance, etc. .

In addition, “does not contain or substantially does not contain copolymerizable monomer A” means not only when it does not contain completely, but also when the copolymerizable monomer A is less than 0.5% by mass in the (meth)acrylic acid ester (co)polymer. Preferably, this means that it is allowed to contain less than 0.1% by mass.

The (meth)acrylic (co)polymer (A) preferably contains a hydroxyl group-containing monomer and/or a nitrogen atom-containing monomer from the viewpoint of providing adhesive strength and cohesion to the adhesive. Therefore, it is particularly preferable that the (meth)acrylic (co)polymer (A) has the above-mentioned “copolymerizable monomer B” or a nitrogen atom-containing monomer, especially “copolymerizable monomer E” as a copolymerization component.

<Compound (B)>

Compound (B) is a compound that has a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule.

Here, examples of the “radical polymerizable functional group having a carbon-carbon double bond” include functional groups having an unsaturated double bond, such as a (meth)acryloyl group and a vinyl group.

Meanwhile, in compound (B), the “radical generator” means a group that generates a radical that initiates a polymerization reaction under excitation by an active energy ray.

As the "radical generator", a structure that is excited by irradiation of active energy rays and generates radicals by generating a hydrogen abstraction reaction is particularly preferable.

Since the compound (B) has a radical generator, for example, the compounds (B) can be polymerized or a cross-linked structure can be formed between the (meth)acrylic (co)polymer (A) molecules. The cohesion of the adhesive resin composition can be improved.

The compound (B) may be any that has a radical polymerizable functional group having a carbon-carbon double bond in the molecule and also has a radical generator, that is, a functional group that generates a radical when irradiated with an active energy ray.

In particular, it is preferable to have a structure capable of generating radicals by extracting hydrogen from molecules of the (meth)acrylic (co)polymer (A), etc.

Examples of the compound (B) include (meth)acryloyl group, benzophenone structure, benzyl structure, o-benzoylbenzoic acid ester structure, thioxanthone structure, 3-ketocoumarin structure, and 2-ethylanthraquinone. Compounds having one structure or two or more structures among the structure and camphorquinone structure can be mentioned.

Among the above, it is preferable that compound (B) is a compound having a (meth)acryloyl group and a benzophenone structure.

More specifically, 4-acryloyloxybenzophenone, 4-acryloyloxyethoxybenzophenone, 4-acryloyloxy-4'-methoxybenzophenone, 4-acryloyloxyethoxy-4 '-methoxybenzophenone, 4-acryloyloxy-4'-bromobenzophenone, 4-acryloyloxyethoxy-4'-bromobenzophenone, 4-methacryloyloxybenzophenone, 4 -Methacryloyloxyethoxybenzophenone, 4-methacryloyloxy-4'-methoxybenzophenone, 4-methacryloyloxyethoxy-4'-methoxybenzophenone, 4-methacrylo Examples include yloxy-4'-bromobenzophenone, 4-methacryloyloxyethoxy-4'-bromobenzophenone, and mixtures thereof.

The lower limit of the content of the compound (B) is preferably 0.2% by mass or more, more preferably 0.3% by mass or more, and most preferably 0.5% by mass or more, based on the total mass of the composition. Additionally, the upper limit is preferably 5% by mass or less, more preferably 2% by mass or less, and most preferably 1% by mass or less, based on the total mass of the composition.

<Initiator (C)>

The initiator (C) may be any initiator composed of a compound other than the compound (B). For example, a thermal initiator or a photoinitiator consisting of a compound other than the above compound (B) can be mentioned.

Examples of the thermal initiator include organic or inorganic peroxides, or 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(isobutyronitrile), 2,2'-azobis( 2,4-dimethylvaleronitrile), 2,2'-azobis-2-hydroxymethylpropionitrile, dimethyl-2,2'-azobis(2-methylpropionate) and 2,2'- Azo-based compounds such as azobis (4-methoxy-2,4-dimethylvaleronitrile) can also be used.

The photoinitiator is a compound that generates active radical species by irradiating light such as ultraviolet rays or visible light, more specifically, light with a wavelength of 200 nm to 780 nm, and either a cleavage type photoinitiator or a hydrogen abstraction type initiator can be used. You can.

Examples of the cleavage type photoinitiator include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexylphenylketone, and 2-hydroxy-2-methyl-1-phenyl-propane. -1-one, 1-(4-(2-hydroxyethoxy)phenyl)-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-[4-{4 -(2-hydroxy-2-methyl-propionyl)benzyl}phenyl]-2-methyl-propan-1-one, oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl) )phenyl)propanone), methyl phenylglyoxylate, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 2-methyl-1-[4-(methylthio) )phenyl]-2-morpholinopropan-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1- Butanone, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide , bis(2,6-dimethoxybenzoyl)2,4,4-trimethylpentylphosphine oxide, and their derivatives.

Examples of the hydrogen abstraction type photoinitiator include benzophenone, 4-methyl-benzophenone, 2,4,6-trimethylbenzophenone, 4-phenylbenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 4 -(meth)acryloyloxybenzophenone, methyl 2-benzoylbenzoate, methyl benzoylformate, bis(2-phenyl-2-oxoacetic acid)oxybisethylene, 4-(1,3-acryloyl-1,4 ,7,10,13-pentaoxotridecyl)benzophenone, thioxanthone, 2-chlorothioxanthone, 3-methylthioxanthone, 2,4-dimethylthioxanthone, 2-methylanthraquinone, 2- Ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone and derivatives thereof can be mentioned.

Among these, a cleavage type photoinitiator is preferable from the viewpoint of its excellent property of opening the unsaturated double bond of the radically polymerizable functional group having a carbon-carbon double bond in the compound (B). Among them, a cleavage-type photoinitiator with an aminoketone structure, a cleavage-type photoinitiator with an acylphosphine oxide structure, a cleavage-type photoinitiator with a hydroxyketone structure, a cleavage-type photoinitiator with a titanocene structure, a cleavage-type photoinitiator with an oxime ester structure, etc. can be particularly preferably exemplified.

In addition, since the cleaved decomposition product of the cleavage type photoinitiator has a lower molecular weight, if a large amount of the cleavage type photoinitiator remains in a low molecular state after photocuring (crosslinking), it may cause a further decrease in cohesion.

However, in the present composition, since the initiator (C) is used to cleave the double bond of the radically polymerizable functional group having a carbon-carbon double bond of the compound (B), the amount used can be significantly reduced, In addition, the compound (B) functions as a cross-linking agent, and the compound (B) itself can polymerize to increase the molecular weight, so even if an initiator (C) is used, the remaining low molecular weight compounds in the system are prevented. It can be suppressed to a minimum and a decrease in the cohesion of the adhesive resin composition can be prevented.

Meanwhile, in the present composition, a hydrogen abstraction type photoinitiator is also useful.

UV-resistant foaming is thought to be a phenomenon in which the cohesive force of the adhesive or the interfacial adhesion of the adherend cannot withstand the outgassing from the adhesive or the adherend, causing foaming. The pressure-sensitive adhesive containing a large amount of the initiator (C) can cause ultraviolet ray foaming due to a decrease in cohesion due to its decomposition product or outgassing. Additionally, an adhesive containing a large amount of a hydrogen abstraction type photoinitiator generates radicals when irradiated with ultraviolet rays, which is a cause of further increasing the generation of outgassing from the adhesive resin composition.

However, in the present composition, as described above, the amount of the initiator (C) can be reduced as much as possible and the cohesive force can be increased, so that the ultraviolet ray resistance foaming property can be especially improved. In this regard, hydrogen abstraction type photoinitiators that tend to generate outgass can also be effectively used.

The lower limit of the content of the initiator (C) is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, and most preferably 0.05% by mass or more, based on the total mass of the composition. Additionally, the upper limit is preferably 1% by mass or less, more preferably 0.3% by mass or less, and most preferably 0.2% by mass or less, based on the total mass of the composition.

In addition, from the viewpoint of cohesion of the adhesive composition and metal corrosion resistance, the lower limit of the content of the initiator (C) relative to 100 parts by mass of the compound (B) is preferably 1 part by mass or more, and 3 parts by mass. It is more preferable that it is more than 5 parts by mass, and it is most preferable that it is 5 parts by mass or more. Additionally, the upper limit is preferably 100 parts by mass or less, more preferably 80 parts by mass or less, and most preferably 50 parts by mass or less, based on the total mass of the composition.

Furthermore, with respect to 100 parts by mass of the (meth)acrylic (co)polymer (A), the total content of the compound (B) and the initiator (C) is preferably 0.2 to 5 parts by mass, especially 0.3 parts by mass or more. parts or less, and more preferably 0.5 parts by mass or more and 1.5 parts by mass or less.

<Rust preventive agent (D)>

This composition may contain a rust preventive agent (D) in order to suppress metal corrosion caused by low molecular weight compounds derived from the initiator (C) occurring in the system.

By containing the rust preventive agent (D), this composition can not only suppress metal corrosion caused by the acidic component of the monomer of the (meth)acrylic (co)polymer (A), but also can suppress corrosion of the metal derived from the initiator (C) generated in the system. Even if a molecular weight compound is present, corrosion of the metal caused by the low molecular weight compound can be suppressed.

The rust preventive agent (D) is preferably a triazole-based compound. Among them, one type or a mixture of two or more types selected from benzotriazole, 1,2,3-triazole and 1,2,4-triazole is particularly preferable.

The benzotriazole may be substituted or unsubstituted benzotriazole, for example, alkyl benzotriazole such as 1,2,3-benzotriazole, methyl-1H-benzotriazole, carboxybenzotriazole, etc. , 1-hydroxybenzotriazole, 5-aminobenzotriazole, 5-phenylthiolbenzotriazole, 5-methoxybenzotriazole, nitrobenzotriazole, chlorobenzotriazole, bromobenzotriazole, fluorobenzotriazole Halogenobenzotriazole such as benzotriazole, copper benzotriazole, silver benzotriazole, and benzotriazole silane compounds can be mentioned. Among these, 1,2,3-benzotriazole, 1-[N,N-bis(2-ethylhexyl)aminomethyl]benzotria from the viewpoint of dispersibility, ease of addition, and metal corrosion prevention effect to the present composition. Sol, 1-[N,N-bis(2-ethylhexyl)aminomethyl]methylbenzotriazole, 2,2'-[[(methyl-1H-benzotriazol-1-yl)methyl]imino]bis Any one type or a mixture of two or more types selected from the group consisting of ethanol is preferable.

Additionally, 1,2,4-triazole is a solid with a melting point of about 120°C, while 1,2,3-triazole has a melting point of about 20°C and is almost liquid at room temperature. Therefore, 1,2,3-triazole has excellent dispersibility when mixed in the present composition, can be mixed uniformly, and has excellent advantages such as being easy to form into a masterbatch.

In the present composition, the content of the rust preventive agent (D) is preferably 10 to 90 parts by mass relative to 100 parts by mass of the compound (B), especially 15 parts by mass or more or 80 parts by mass or less, and especially 20 parts by mass or more or 70 parts by mass. Parts by mass or less are particularly preferable.

The content of the rust preventive agent (D) contained in this composition is preferably 0.01 to 5% by mass, based on the total mass of the composition, and more preferably 0.1% by mass or more or 1% by mass or less, and especially 0.2% by mass. It is more preferable that it is more than % by mass or less than 0.5% by mass.

<Cross-linking agent (E)>

This composition may further contain a crosslinking agent (E), if necessary.

Examples of the crosslinking agent (E) include polyfunctional monomers, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hydrogenated tolylene diisocyanate, 1,3-xylylene diisocyanate, and 1,4-xylylene diisocyanate. , hexamethylene diisocyanate, diphenylmethane-4,4-diisocyanate, isophorone diisocyanate, 1,3-bis(isocyanate methyl)cyclohexane, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, tri Isocyanate-based compounds such as phenylmethane triisocyanate, adducts between these isocyanate-based compounds and polyol compounds such as trimethylolpropane, isocyanate-based crosslinking agents such as biuret and isocyanurate forms of these polyisocyanate compounds, and polyethylene glycol. Epoxy-based cross-linking agents such as diglycidyl ether, diglycidyl ether, and trimethylolpropane triglycidyl ether, melamine resin-based cross-linking agents, aziridine-based cross-linking agents, oxazoline-based cross-linking agents, urea-based cross-linking agents, metal salt-based cross-linking agents, and metal chelate-based cross-linking agents. , amino resin-based crosslinking agents, metal alkoxide-based crosslinking agents, and peroxide-based crosslinking agents.

These crosslinking agents (E) can be used one type or in combination of two or more types.

Additionally, a (meth)acrylate monomer having an organic functional group such as a glycidyl group, a hydroxyl group, or an isocyanate group may be used to coexist a crosslinked structure using different crosslinkable reactive groups.

Among the above, polyfunctional monomers are preferable, and examples of the polyfunctional monomers include 1,4-butanediol di(meth)acrylate, glycerin di(meth)acrylate, neopentyl glycol di(meth)acrylate, and glycerol glycol. Sidyl ether di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, tricyclodecane dimethacrylate, tricyclodecane dimethanol di. (meth)acrylate, bisphenol A polymethoxy di(meth)acrylate, bisphenol A polypropoxy di(meth)acrylate, bisphenol F polyethoxy di(meth)acrylate, ethylene glycol di(meth)acrylate, Neopentyl glycol di(meth)acrylate, trimethylolpropanetrioxyethyl(meth)acrylate, ε-caprolactone modified tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, pentaerythritol tri( Meth)acrylate, propoxylated pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, propoxylated pentaerythritol tetra(meth)acrylate, ethoxylated Sihwa pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, polyethylene glycol di(meth)acrylate, tris(acryloxyethyl)isocyanurate, dipentaerythritol hexa(meth)acrylate, Dipentaerythritol penta(meth)acrylate, tripentaerythritol hexa(meth)acrylate, tripentaerythritol penta(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, hydroxypivalic acid neophene Di(meth)acrylate of ε-caprolactone adduct of glycol, trimethylolpropane tri(meth)acrylate, trimethylolpropane polyethoxytri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, etc. In addition to UV-curable multifunctional (meth)acrylic monomers, multifunctional (meth)acrylic oligomers such as polyester (meth)acrylate, epoxy (meth)acrylate, urethane (meth)acrylate, and polyether (meth)acrylate. can be mentioned. These may be used one type or in combination of two or more types.

The content of the crosslinking agent (E) is preferably 10 parts by mass or less per 100 parts by mass of the (meth)acrylic (co)polymer (A), especially 0.05 parts by mass or more or 5 parts by mass or less, and especially 0.1 parts by mass or more. Alternatively, it is more preferable to have it in a ratio of 3 parts by mass or less. By using the cross-linking agent (E), negative effects such as lowering of cohesion due to remaining low molecular weight compounds can be avoided.

In addition, since compound (B) also functions as a cross-linking agent in this composition, high cohesive strength can be obtained without necessarily using a cross-linking agent.

Therefore, from this point of view, it is particularly preferable not to use the cross-linking agent (E).

<Other ingredients>

As "other ingredients" other than the above contained in this composition, for example, if necessary, a tackifying resin, antioxidant, light stabilizer, metal deactivator, anti-aging agent, moisture absorbent, polymerization inhibitor, ultraviolet absorber, It is possible to appropriately contain various additives such as silane coupling agents and inorganic particles.

Additionally, if necessary, a reaction catalyst such as a tertiary amine compound, a quaternary ammonium compound, or a tin laurate compound may be appropriately contained.

<Preparation of this composition>

This composition includes the (meth)acrylic (co)polymer (A), the compound (B) and initiator (C), optionally a rust inhibitor (D), optionally a crosslinking agent (E), and further, if necessary. It can be obtained by mixing the other ingredients in a predetermined amount.

The mixing method is not particularly limited, and the mixing order of each component is not particularly limited.

Additionally, a heat treatment process may be added when manufacturing this composition. In this case, it is preferable to perform heat treatment after mixing each component of the composition in advance. A masterbatch obtained by concentrating various mixed ingredients may be used.

Additionally, the equipment for mixing is not particularly limited, and for example, a universal kneader, planetary mixer, banbari mixer, kneader, gate mixer, pressure kneader, three rolls, or two rolls can be used. If necessary, it may be mixed using a solvent.

Additionally, this composition can be used as a solvent-free system that does not contain a solvent. By using it as a solvent-free system, it can be provided with the advantage that no solvent remains and heat resistance and light resistance are improved.

<<This adhesive sheet>>

The adhesive sheet (also referred to as “this adhesive sheet”) according to an example of an embodiment of the present invention has an adhesive layer formed from the present composition.

The pressure-sensitive adhesive layer in the present pressure-sensitive adhesive sheet may be a single layer or a multi-layer, and in the case of a multi-layer, another layer such as a so-called base layer may be interposed.

When the adhesive layer has a multilayer structure having different layers, it is preferable that the surface layer of the present adhesive sheet is an adhesive layer formed from the present composition.

Additionally, the pressure-sensitive adhesive layer may have active energy ray curability that leaves room for curing by active energy rays. In this case, it may contain reaction decomposition products of the initiator (C).

Additionally, when the present adhesive sheet has a multilayer structure, it is preferable that the adhesive layers on the front and back layers are formed from the present composition that does not contain a crosslinking agent (E) from the viewpoint of improving the adhesive strength and reliability of the adhesive sheet.

In addition, when the present adhesive sheet has a multilayer structure, the adhesive layers of layers other than the front and back layers are preferably formed of an adhesive resin composition containing a crosslinking agent (E) from the viewpoint of improving the handling and cutting properties of the adhesive sheet. At this time, the adhesive resin composition may be this composition or a conventionally known adhesive resin composition.

The thickness of this adhesive sheet is preferably 10 μm to 500 μm, more preferably 15 μm or more or 400 μm or less, and especially 20 μm or more or 350 μm or less.

<<This curable adhesive sheet>>

An active energy ray-curable adhesive sheet (also referred to as “mainly curable adhesive sheet”) according to an example of an embodiment of the present invention is a composition in which the radical generator of the compound (B) is excited by irradiation of an active energy ray. , It has a structure that generates radicals by generating a hydrogen abstraction reaction.

At this time, when a cleavage type photoinitiator is used as the initiator (C), the present curable adhesive sheet may contain a reaction decomposition product of the initiator (C).

Since the compound (B) has the structure, a cross-linked structure can be formed between the molecules of the (meth)acrylic polymer, for example, by irradiation of active energy rays, so the compound (B) has (post-)curability. It can be provided.

By having such active energy ray curability, the adhesive sheet has relatively excellent flexibility before curing (e.g., before bonding to the adherend), and also increases cohesion after curing (e.g., after bonding to the adherend), It can provide excellent anti-foaming reliability.

<Usage form of main adhesive sheet or main curable adhesive sheet>

The present adhesive sheet or the present curable adhesive sheet can also be used as a single adhesive sheet. For example, the adhesive sheet or curable adhesive sheet can be used by directly applying the composition to an adherend to form a sheet, extruding the composition directly, or injecting it into a mold. there is. Furthermore, the present adhesive sheet or the present curable adhesive sheet can also be used by directly filling the present composition between members such as conductive members.

On the other hand, the present adhesive sheet or the present curable adhesive sheet can also be used as an adhesive sheet (also referred to as “adhesive sheet laminate”) provided with an adhesive layer formed from the present composition. For example, this composition can be used in the form of an adhesive sheet provided with a release film molded into a single- or multi-layer sheet shape on a release film.

Examples of the material of the release film include polyester film, polyolefin film, polycarbonate film, polystyrene film, acrylic film, triacetylcellulose film, and fluororesin film. Among these, polyester films and polyolefin films are particularly preferable.

The thickness of the release film is not particularly limited. Among them, for example, from the viewpoint of processability and handling, it is preferable that it is 25 ㎛ to 500 ㎛, especially 38 ㎛ or more or 250 ㎛ or less, and especially 50 ㎛ or more or 200 ㎛ or less.

<<Optical members>>

An optical member according to an example of an embodiment of the present invention includes a substrate having metal wiring on at least one side of the present adhesive sheet or the present curable adhesive sheet.

At this time, the metal wiring is, for example, made of metal such as ITO, Cu, or Ag.

Materials of the substrate include, in addition to glass, alicyclic polyolefin resins such as acrylic resins, polycarbonate resins, and cycloolefin polymers, styrene resins, polyvinyl chloride resins, phenolic resins, melamine resins, epoxy resins, etc. It may be made of plastic.

<<Main laminate>>

A laminate for an image display device (referred to as “main laminate”) related to an example of an embodiment of the present invention includes a main adhesive sheet or a main curable adhesive sheet interposed between two structural members for an image display device. It has a configuration that is accomplished.

At this time, the two image display device structural members are laminates in which at least one of them is any one of the group consisting of a touch sensor, an image display panel, a surface protection panel, a polarizing film, and a retardation film, or a combination of two or more types. You can pick up a chain.

Specific examples of the present laminate include, for example, release film/main adhesive sheet or main curable adhesive sheet/touch panel, image display panel/main adhesive sheet or main curable adhesive sheet/touch panel, image display panel/main adhesive sheet or main body. Curable adhesive sheet/touch panel/main adhesive sheet or main curable adhesive sheet/protection panel, polarizing film/main adhesive sheet or main curable adhesive sheet/touch panel, polarizing film/main adhesive sheet or main curable adhesive sheet/touch panel/main Configurations such as an adhesive sheet or a main curable adhesive sheet/protection panel can be mentioned.

The touch panel includes a structure in which a touch panel function is embedded in a protection panel and a structure in which a touch panel function is embedded in an image display panel.

Therefore, the present laminate may be, for example, a release film/main adhesive sheet or main curable adhesive sheet/protection panel, a release film/main adhesive sheet or main curable adhesive sheet/image display panel, an image display panel/main adhesive sheet or main It may be comprised of a curable adhesive sheet/protection panel, etc.

In addition, in the above configuration, all configurations that interpose the conductive layer between the main adhesive sheet or main curable adhesive sheet and adjacent members such as a touch panel, a protection panel, an image display panel, and a polarizing film can be mentioned. there is. However, it is not limited to these stacked examples.

Additionally, examples of the touch panel include those of a resistive film type, capacitance type, and electromagnetic induction type. Among them, the electrostatic capacitance method is preferable.

Materials of the protective panel include, in addition to glass, alicyclic polyolefin resins such as acrylic resins, polycarbonate resins, and cycloolefin polymers, styrene resins, polyvinyl chloride resins, phenolic resins, melamine resins, and epoxy resins. It may be made of plastic.

The image display panel is composed of other optical films such as polarizing films and retardation films, liquid crystal materials, and a backlight system (usually, the surface of the adhesive resin composition or adhesive article adhered to the image display panel is an optical film). , Depending on the control method of the liquid crystal material, there are STN method, VA method, IPS method, etc., and any method may be used.

This laminate can be used as a structural member of image display devices such as liquid crystal displays, organic EL displays, inorganic EL displays, electronic papers, plasma displays, and micro electromechanical system (MEMS) displays.

<<This image display device>>

An image display device (also referred to as “this image display device”) related to an example of an embodiment of the present invention is an image display device provided with the present laminate.

Specific examples of the image display device include liquid crystal displays, organic EL displays, inorganic EL displays, electronic papers, plasma displays, and microelectromechanical system (MEMS) displays.

<<Explanation of phrase>>

In the present invention, when expressed as “ It also includes the meaning of “smaller than Y.”

In addition, when expressed as “more than Includes.

In addition, in the present invention, “sheet” conceptually includes sheets, films, and tapes.

<Example>

Hereinafter, it will be described in more detail through examples and comparative examples. However, the present invention is not limited to these examples.

<Example 1>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of copolymer (A-1, mass average molecular weight 490,000, glass transition temperature (Tg) -19°C), and radical polymerization having a carbon-carbon double bond As a compound (B) having a sexual functional group and a radical generator, 5 g of 4-methacryloyloxybenzophenone (B-1, molecular weight 266, melting point 70°C), and as an initiator (C) other than (B), 2, 4 g of a mixture of 4,6-trimethylbenzophenone and 4-methylbenzophenone (C-1) and 3 g of 1,2,4-triazole (D-1) as a rust inhibitor (D) were uniformly melted and kneaded, Resin composition 1 was prepared.

In addition, the copolymer (A-1) was a (meth)acrylic acid ester (co)polymer that did not contain structural units derived from carboxyl group-containing monomers but also contained structural units derived from hydroxyl group-containing monomers. Here, “a structural unit derived from a certain monomer” means a structural unit as a result of a copolymerization reaction of the monomer, that is, a unit that constitutes a copolymer.

1,2,4-triazole (D-1) as a metal corrosion inhibitor has an extinction coefficient of 0.3 mL/(g·cm) at 365 nm and a water solubility of 1000 g/L at 25°C. It was higher than

The resin composition 1 was sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF” manufactured by Mitsubishi Chemical Corporation, thickness 75 μm/“Diafoil MRT” manufactured by Mitsubishi Chemical Corporation, thickness 38 μm), and the thickness was 100 μm. It is shaped into a sheet at a temperature of 80°C, irradiated with light from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm is 1500 mJ/cm2, and pre-cured to form a transparent double-sided adhesive sheet. 1 was prepared.

In addition, the adhesive layer in transparent double-sided adhesive sheet 1 still had room for photocuring by light irradiation (precured product).

<Example 2>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-1), and as a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, (B- 1) 5 g, and as an initiator (C) other than (B), 1 g of oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone)(C-2) As a rust preventive (D), 3 g of 1,2,3-triazole (D-2) was uniformly melt-kneaded to prepare resin composition 2.

In addition, 1,2,3-triazole (D-2) as a metal corrosion inhibitor has an extinction coefficient of 0.3 mL/(g·cm) at 365 nm, and a water solubility at 25°C of less than 1000 g/L. It was high.

As in the case of Example 1, the resin composition 2 was shaped into a sheet with a thickness of 100 μm, and from one side of the polyethylene terephthalate film, it was illuminated with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1500 mJ/cm2. Transparent double-sided adhesive sheet 2 was produced by irradiating light and pre-curing.

Additionally, the adhesive layer in the transparent double-sided adhesive sheet 2 still had room for photocuring by light irradiation (precured product).

<Example 3>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-1), and as a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, (B- 1) Resin composition 3 was prepared by uniformly melting and kneading 10 g of (C-2) as an initiator (C) other than (B), and 3 g of (D-2) as a rust preventive (D).

As in the case of Example 1, the resin composition 3 was shaped into a sheet to have a thickness of 100 μm, and from one side of the polyethylene terephthalate film, it was illuminated with a high-pressure mercury lamp so that the amount of integrated light at a wavelength of 365 nm was 1500 mJ/cm2. Transparent double-sided adhesive sheet 3 was produced by irradiating light and pre-curing.

In addition, the adhesive layer in transparent double-sided adhesive sheet 3 still had room for photocuring by light irradiation (precured product).

<Example 4>

Resin composition 3 was shaped into a sheet to a thickness of 100 μm, as in Example 1, and was illuminated from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 3500 mJ/cm2. was investigated to prepare a transparent double-sided adhesive sheet 4.

<Example 5>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-1), and as a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, (B- 1) Uniformly melt-knead 5 g of 2,2-dimethoxy-1,2-diphenylethan-1-one (C-3) as an initiator (C) other than (B), and prepare resin composition 4. was manufactured.

As in the case of Example 1, the resin composition 4 was shaped into a sheet with a thickness of 100 μm, and from one side of the polyethylene terephthalate film, it was illuminated with a high-pressure mercury lamp so that the amount of integrated light at a wavelength of 365 nm was 1500 mJ/cm2. Transparent double-sided adhesive sheet 5 was produced by irradiating light and pre-curing.

In addition, the adhesive layer in transparent double-sided adhesive sheet 5 still had room for photocuring by light irradiation (precured product).

<Example 6>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of copolymer (A-2, mass average molecular weight 510,000, Tg-18°C), a radical polymerizable functional group having a carbon-carbon double bond, and a radical generator 5 g of (B-1) as a compound (B) having in the molecule, 1 g of (C-2) as an initiator (C) other than (B), and 3 g of (D-1) as a rust inhibitor (D). Resin composition 5 was prepared by uniformly melt-kneading.

In addition, the copolymer (A-2) was a (meth)acrylic acid ester (co)polymer that did not contain structural units derived from carboxyl group-containing monomers but also contained structural units derived from hydroxyl group-containing monomers.

As in the case of Example 1, the resin composition 5 was shaped into a sheet with a thickness of 100 μm, and from one side of the polyethylene terephthalate film, it was illuminated with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1500 mJ/cm2. Transparent double-sided adhesive sheet 6 was produced by irradiating light and pre-curing.

Additionally, the adhesive layer in the transparent double-sided adhesive sheet 6 still had room for photocuring by light irradiation (precured product).

<Example 7>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-2), and as a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, (B- 1) 5 g of initiator (C) other than (B), 1 g of (C-2), 3 g of (D-1) as the rust inhibitor (D), and 1,10-decanediol as the crosslinking agent (E). Resin composition 6 was prepared by uniformly melting and kneading 10 g of diacrylate (E-1).

As in the case of Example 1, the resin composition 6 was shaped into a sheet with a thickness of 100 μm, and irradiated from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the amount of integrated light at a wavelength of 365 nm was 3500 mJ/cm2. Transparent double-sided adhesive sheet 7 was manufactured by irradiating light.

<Example 8>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of copolymer (A-3, mass average molecular weight 440,000, Tg-6°C), a radical polymerizable functional group having a carbon-carbon double bond, and a radical generator 5 g of (B-1) as a compound (B) having in the molecule, 1 g of (C-2) as an initiator (C) other than (B), and 3 g of (D-2) as a rust inhibitor (D). Resin composition 7 was prepared by uniformly melt-kneading.

In addition, the copolymer (A-3) was a (meth)acrylic acid ester (co)polymer that did not contain structural units derived from carboxyl group-containing monomers but also contained structural units derived from hydroxyl group-containing monomers.

As in the case of Example 1, the resin composition 7 was shaped into a sheet to have a thickness of 100 μm, and from one side of the polyethylene terephthalate film, it was illuminated with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1000 mJ/cm2. Transparent double-sided adhesive sheet 8 was produced by irradiating light and pre-curing.

Additionally, the adhesive layer in the transparent double-sided adhesive sheet 8 still had room for photocuring by light irradiation (precured product).

<Example 9>

Resin Composition 2 is sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF” with a thickness of 75 μm/“Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 25 μm to form a surface layer sheet. 9-1 was prepared.

Resin composition 2 is sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRV” with a thickness of 100 μm and “Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 25 μm to form a surface layer sheet. 9-1' was prepared.

As the (meth)acrylic acid ester (co)polymer (A), (A-1) 1 kg, as the initiator (C) other than (B), (C-2) 10 g, as the crosslinking agent (E), pentaerythritol triacryl Resin composition 8 was prepared by uniformly melting and kneading 120 g of rate (E-2).

The resin composition 8 is sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF” with a thickness of 75 μm/“Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 50 μm, forming a sheet for the intermediate layer. Sheet 9-2 was prepared.

The PET film on both sides of the intermediate layer sheet 9-2 is sequentially peeled and removed, and the adhesive surfaces of the surface layer sheets 9-1 and 9-1' are sequentially bonded to both surfaces to form 9-1/9-2/9. A laminate consisting of -1' was manufactured.

Through the PET film remaining on the surfaces of 9-1 and 9-1', light is irradiated with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm is 1500 mJ/cm2, and pre-cured to produce transparent double-sided adhesive sheet laminate 9. was manufactured.

In addition, the adhesive layer in the transparent double-sided adhesive sheet laminate 9 still had room for photocuring by light irradiation (precured product).

<Example 10>

As the (meth)acrylic acid ester (co)polymer (A), a copolymer (A-) consisting of n-butylacrylate (71% by mass)/2-ethylhexyl acrylate (26% by mass)/acrylic acid (3% by mass) 4, 1 kg of mass average molecular weight 490,000, Tg-30°C), 5 g of (B-1) as a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator in the molecule, ( Resin composition 9 was prepared by uniformly melting and kneading 1 g of (C-2) as an initiator (C) other than B) and 3 g of (D-2) as a rust preventive (D).

Resin Composition 9 is sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF” with a thickness of 75 μm/“Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 25 μm to form a surface layer sheet. 10-1 was prepared.

Resin composition 9 is sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRV” with a thickness of 100 μm and “Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 25 μm to form a surface layer sheet. 10-1' was prepared.

As the (meth)acrylic acid ester (co)polymer (A), (A-4) 1 kg, as the initiator (C) other than (B), (C-2) 10 g, as the crosslinking agent (E), propoxylated penta Resin composition 10 was prepared by uniformly melting and kneading 200 g of erythritol triacrylate (E-3).

The resin composition 10 is sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF” with a thickness of 75 μm/“Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 50 μm, forming a sheet for the intermediate layer. Sheet 10-2 was prepared.

The PET films on both sides of the intermediate layer sheet 10-2 are sequentially peeled and removed, and the adhesive surfaces of the surface layer sheets 10-1 and 10-1' are sequentially bonded to both surfaces to form 10-1/10-2/10. A laminate consisting of -1' was manufactured.

Through the PET film remaining on the surface of 10-1 and 10-1', light is irradiated with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm is 1000 mJ/cm2, and pre-cured, forming a transparent double-sided adhesive sheet laminate 10. was manufactured.

In addition, the adhesive layer in the transparent double-sided adhesive sheet laminate 10 still had room for photocuring by light irradiation (precured product).

<Comparative Example 1>

As the (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-2), and as the initiator (C) other than (B), 2,4,6-trimethylbenzophenone and 4-methylbenzophenone Resin composition 11 was prepared by uniformly melting and kneading 15 g of mixture (C-1) and 3 g of (D-1) as a rust inhibitor (D).

The resin composition 11 was sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF”, thickness 75 µm/“Diafoil MRT”, thickness 38 µm), and formed into a sheet at a temperature of 80°C to a thickness of 100 µm. was shaped, and irradiated with light from one side of the polyethylene terephthalate film using a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1500 mJ/cm2, and pre-cured to prepare a transparent double-sided adhesive sheet 11.

Additionally, the adhesive layer in the transparent double-sided adhesive sheet 11 still had room for photocuring by light irradiation (precured product).

<Comparative Example 2>

As the (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-3), and as the initiator (C) other than (B), 2,4,6-trimethylbenzophenone and 4-methylbenzophenone Resin composition 12 was prepared by uniformly melting and kneading 15 g of mixture (C-1) and 3 g of (D-1) as a rust inhibitor (D).

The resin composition 12 is sandwiched between two peeled polyethylene terephthalate films, “Diafoil MRF” with a thickness of 75 μm and “Diafoil MRT” with a thickness of 38 μm, and shaped into a sheet at a temperature of 80°C to a thickness of 100 μm. Then, light was irradiated from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1500 mJ/cm 2 and precured, thereby producing a transparent double-sided adhesive sheet 12.

In addition, the adhesive layer in the transparent double-sided adhesive sheet 12 still had room for photocuring by light irradiation (precured product).

<Comparative Example 3>

As the (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-2), and as the initiator (C) other than (B), 2,4,6-trimethylbenzophenone and 4-methylbenzophenone Resin composition 13 was prepared by uniformly melting and kneading 5 g of mixture (C-1) and 3 g of (D-1) as a rust inhibitor (D).

The resin composition 13 is sandwiched between two peeled polyethylene terephthalate films, “Diafoil MRF” with a thickness of 75 μm and “Diafoil MRT” with a thickness of 38 μm, and shaped into a sheet at a temperature of 80°C to a thickness of 100 μm. Then, light was irradiated from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1500 mJ/cm 2 and precured, thereby producing a transparent double-sided adhesive sheet 13.

In addition, the adhesive layer in the transparent double-sided adhesive sheet 13 still had room for photocuring by light irradiation (precured product).

<Comparative Example 4>

As a (meth)acrylic acid ester (co)polymer (A), (A-2) 1 kg, as an initiator (C) other than (B), (C-1) 7.5 g, and bis (2,4,6) Resin composition 14 was prepared by uniformly melting and kneading 7.5 g of -trimethylbenzoyl)-phenylphosphine oxide (C-4) and 10 g of (E-1) as a crosslinking agent (E).

The resin composition 14 is sandwiched between two peeled polyethylene terephthalate films, “Diafoil MRF” with a thickness of 75 μm and “Diafoil MRT” with a thickness of 38 μm, and shaped into a sheet at a temperature of 80°C to a thickness of 100 μm. Then, light was irradiated from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 3500 mJ/cm2, and a transparent double-sided adhesive sheet 14 was produced.

<Comparative Example 5>

As the (meth)acrylic acid ester (co)polymer (A), (A-4) 1 kg, as the initiator (C) other than (B), (C-1) 15 g, and as the rust inhibitor (D), (D) -2) Resin composition 15 was prepared by uniformly melting and kneading 3g.

Resin composition 15 was sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRF” with a thickness of 75 μm and “Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 25 μm to form a surface layer sheet. 15-1 was prepared.

Resin composition 15 was sandwiched between two peeled polyethylene terephthalate films (“Diafoil MRV” with a thickness of 100 μm and “Diafoil MRT” with a thickness of 38 μm) and shaped into a sheet with a thickness of 25 μm, forming a surface layer sheet. 15-1' was prepared.

The PET film on both sides of the intermediate layer sheet 10-2 of Example 10 was sequentially peeled and removed, and the adhesive surfaces of the surface layer sheets 15-1 and 15-1' were sequentially bonded to both surfaces to form 15-1/ A laminate consisting of 10-2/15-1' was manufactured.

Through the PET film remaining on the surface of 15-1 and 15-1', light is irradiated with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm is 1000 mJ/cm2, and pre-cured, forming a transparent double-sided adhesive sheet laminate 15. was manufactured.

In addition, the adhesive layer in the transparent double-sided adhesive sheet laminate 15 still had room for photocuring by light irradiation (precured product).

<Comparative Example 6>

As a (meth)acrylic acid ester (co)polymer (A), 1 kg of (A-2), and as a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, (B- 1) Resin composition 16 was prepared by uniformly melting and kneading 5 g.

The resin composition 16 is sandwiched between two peeled polyethylene terephthalate films, “Diafoil MRF” with a thickness of 75 μm and “Diafoil MRT” with a thickness of 38 μm, and shaped into a sheet at a temperature of 80°C to a thickness of 100 μm. Then, light was irradiated from one side of the polyethylene terephthalate film with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 1500 mJ/cm 2 and precured, thereby producing a transparent double-sided adhesive sheet 16.

Additionally, the adhesive layer in the transparent double-sided adhesive sheet 16 still had room for photocuring by light irradiation (precured product).

[Physical property evaluation]

The physical properties of the transparent double-sided adhesive sheets obtained in Examples and Comparative Examples were measured as follows.

<Power of protection>

The transparent double-sided adhesive sheets 1 to 16 with a thickness of 100 μm were cut into 40 mm 38 ㎛) was stacked with a hand roller, and then cut into strips of 25 mm in width x 100 mm in length to prepare test pieces.

Next, the remaining release film was peeled off, and it was attached to a stainless steel plate (120 mm × 50 mm × thickness 1.2 mm) with a hand roller so that the adhesive area was 25 mm × 20 mm.

After that, the test piece was cured in an atmosphere of 40°C for 15 minutes, a weight of 500gf (4.9N) was installed on the test piece in the vertical direction, and the test piece was left to stand for 30 minutes. After that, the adhesive position of the SUS and the test piece was shifted downward ( mm), that is, the amount of deviation was measured.

<Step absorbency>

The transparent double-sided adhesive sheets 1 to 16 were cut to 50 × 80 mm using a Thompson punch with a release film laminated thereon. The release film on one side was peeled off, and the exposed adhesive surface was placed on the printed surface of soda lime glass (82 mm The four sides were pressed against the printing steps using a vacuum press (temperature 25°C, press pressure 0.1 MPa). Next, peel off the remaining release film, press-attach soda lime glass (82㎜ It adhered, and a glass/adhesive sheet/glass laminate with steps was manufactured.

The manufactured laminate was visually observed.

“△(usual)” indicates that the adhesive sheet does not follow the printing step and bubbles remain in the vicinity of the printing step, making it unsuitable for bonding at the printing step. “△(usual)” indicates that there were no air bubbles at a printing step of 10㎛ and the appearance was good, but at 25㎛, air bubbles remained. It was judged as “○ (good)”, and “◎ (very good)” with no bubbles and good appearance for both the 10㎛ and 25㎛ printing steps.

<Cutting processability>

Transparent double-sided adhesive sheets 1 to 16 were cut to 50 × 50 mm using a Thompson punch with a release film laminated thereon. After peeling off the single-sided release film, the adhesive alone is cut to 30 Manufactured.

When the release film is peeled, the glue that stretches like thread or falls off is considered defective. If the number of defective products exceeds 10, it is rated as “×(poor),” and if the number of defective products is limited to 10 or less, it is rated as ○ (good). 」, and in addition, a case where defective products were suppressed to 1 or less was judged as ◎ (very good).

<Storage stability>

The cut products of adhesive sheets 1 to 16 manufactured in the evaluation of cutting processability were laminated so as to be sandwiched between glass plates of 50 mm I worked for 200 hours.

If the adhesive sheet is noticeably crushed after curing and the glue sticks out more than 0.1 mm from the end, it is judged as “×(poor)”; if the glue sticks out is suppressed to 0.1 mm or less and there is no problem in practical terms, it is judged as “○ (good)” did.

<Moist heat resistance foaming>

Transparent double-sided adhesive sheets 1 to 16 were cut to 50 × 78 mm using a Thompson punch with a release film laminated thereon. The release film on one side was peeled off, and the exposed adhesive surface was bonded to soda lime glass 1 (54 x 82 mm, t 0.6 mm) with a hand roll. Next, the release film on the adhesive side of the polarizing plate (VLC2 manufactured by Sanritsu Corporation) with adhesive was peeled off, and the exposed adhesive surface was bonded to soda lime glass 2 (54 x 82 mm, t 0.6 mm) with a hand roll. Additionally, another release film of the transparent double-sided adhesive sheets 1 to 16 bonded to soda lime glass 1 was peeled, and the protective film on the polarizing plate side was bonded to the peeled polarizing plate using a hand roll.

Next, autoclave treatment (60°C, gauge pressure 0.2 MPa, 20 minutes) was performed to final attach.

For Examples 1 to 3, 5 to 6, and 8 to 10, and Comparative Examples 1 to 3 and 5 to 6, a high-pressure mercury lamp was used from one side of the soda lime glass, and the accumulated light amount at 365 nm was 2000 mJ/cm2. The adhesive sheet was photocured by irradiating as much light as possible (post-cured product). Afterwards, samples for evaluation of heat foaming resistance (soda lime glass 1/transparent double-sided adhesive sheet/polarizer with adhesive/soda lime glass 2) were prepared by curing at room temperature for 12 hours.

In addition, for the post-cured product, the holding power after post-curing was also measured in the same manner as the method described above.

These were left standing in an environment at 85°C for 300 hours, and the presence or absence of foaming was visually observed.

Those where bubbles were generated at the interface of the polarizer/transparent double-sided adhesive sheet were judged as “×(poor)”, and those where no bubbles were generated and the appearance was good were judged as “○ (good)”.

<UV-resistant foaming properties>

Transparent double-sided adhesive sheets 1 to 16 were cut to 200 × 150 mm using a Thompson puncher with release films laminated thereon. The release film on one side of the transparent double-sided adhesive sheet was peeled off, and the exposed adhesive surface was bonded to the entire surface of soda lime glass (200 x 150 mm, t 0.6 mm) with a hand roll. Next, another release film was peeled off, and the exposed adhesive surface was vacuum pressed with another sheet of soda lime glass (200 × 150 mm, t 0.6 mm) (23°C, press pressure 0.1 MPa, 1 minute). Next, autoclave treatment (60°C, gauge pressure 0.2 MPa, 20 minutes) was performed to final attach.

For Examples 1 to 3, 5 to 6, and 8 to 10, and Comparative Examples 1 to 3 and 5 to 6, a high-pressure mercury lamp was used from one glass side so that the accumulated light amount at 365 nm was 2000 mJ/cm2. The adhesive sheet was photocured by irradiating light (post-cured product). Afterwards, samples for evaluation of UV resistance foaming properties were prepared by curing at room temperature for 12 hours.

These were left to stand in the following environment for 3 hours, 8 hours, and 24 hours, and the presence or absence of foaming or microbubbles under a strong UV irradiation environment was visually observed over time.

<Device> Santest CPS+ (made by Toyomi Knight)

<Light source> Xenon arc lamp (air-cooled, wavelength 270㎚ cutoff filter)

<Irradiance> 765W/㎡ (wavelength 800nm or less)

<Temperature> BST 83℃

Then, ultraviolet foaming resistance was determined based on the following criteria.

After standing for 3 hours, large foam or a large number of micro-bubbles were formed as “×(poor)”. After standing for 3 hours, the appearance was good. Additionally, if foaming or micro-bubbles were formed after standing for 8 hours, it was marked as “△(usual)”, 8. After standing for a time, the appearance was good, and those with foaming or microbubbles after standing for 24 hours were judged as "○ (good"), and those with good appearance even after 24 hours were judged as "◎ (very good)."

<ITO corrosion resistance>

ITO200Å was deposited on a glass of 60 A substrate for evaluating corrosion resistance of ITO was prepared.

The single-sided release films of the double-sided adhesive sheets 1 to 16 were peeled off, roll-laminated to a PET film (Diafoil T100 manufactured by Mitsubishi Chemical Corporation, thickness 50 μm), and then cut to a width of 52 mm. After that, the release film on the other side was peeled off, and the adhesive sheet was glued to the substrate with a roll so that it was positioned between the electrodes, and then autoclaved (60°C, gauge pressure 0.2 MPa, 20 minutes) to final bond it. .

For Examples 1 to 3, 5 to 6, and 8 to 10, and Comparative Examples 1 to 3 and 5 to 6, light was irradiated from the PET film side with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 2000 mJ/cm2. and photocured (post-cured product). After that, a sample for evaluating ITO corrosion resistance, as shown in FIG. 1, was prepared by curing at room temperature for 12 hours.

For this sample, an environmental test was performed in a moist heat environment at 65°C, 90% RH x 500h, and an increase in the resistance value between electrodes was confirmed.

In the above environmental test, “× (poor)” indicates that the increase in resistance value exceeds 5%, “○ (good”) indicates that the increase in resistance value is suppressed to 4% or less, and “○ (good”) indicates that the increase in resistance value is suppressed to 3% or less. The result was judged as “◎ (very good)”.

<Cu corrosion resistance>

On a glass of 60 A substrate for evaluating Cu corrosion resistance was prepared by forming a Cu 3000Å film in the order of thickness.

The single-sided release films of the double-sided adhesive sheets 1 to 16 were peeled off, roll-laminated to a PET film (Diafoil T100 manufactured by Mitsubishi Chemical Corporation, thickness 50 μm), and then cut to a width of 52 mm. After that, the release film on the other side was peeled off, and the adhesive sheet was glued to the substrate with a roll so that it was positioned between the electrodes, and then autoclaved (60°C, gauge pressure 0.2 MPa, 20 minutes) to final bond it. .

For Examples 1 to 3, 5 to 6, and 8 to 10, and Comparative Examples 1 to 3 and 5 to 6, light was irradiated from the PET film side with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 2000 mJ/cm2. and photocured (post-cured product). After that, a sample for evaluating Cu corrosion resistance, as shown in FIG. 1, was prepared by curing at room temperature for 12 hours.

For this sample, an environmental test was performed in a moist heat environment at 65°C, 90% RH x 500h, and an increase in the resistance value between electrodes was confirmed.

In the above environmental test, “× (poor)” indicates that the increase in resistance value exceeds 5%, “○ (good”) indicates that the increase in resistance value is suppressed to 3% or less, and additionally, “○ (good”) indicates that the increase in resistance value is suppressed to 1% or less. The result was judged as “◎ (very good)”.

<Ag corrosion resistance>

As a conductive member containing silver, silver nanowire film (Activgrid Film manufactured by C3nano, base polyethylene terephthalate (thickness 50㎛), surface resistance value 50Ω/□, equipped with overcoating layer, total light transmittance>91%, haze≤0.9%, b *≤1.3) was prepared.

As shown in Figure 2, the silver nanowire film was cut to 45 mm in length x 80 mm in width, and silver paste (Dodite D-550, manufactured by Fujikura Kasei Co., Ltd.) was applied about 3 to 5 mm in the longitudinal direction so that the spacing between electrodes was 50 mm. It was applied to a width of 9 mm, dried, and cut laterally so that the sheet had a vertical width of 9 mm. This silver nanowire film including 9 mm x 80 mm x 5 silver paste electrodes was placed in parallel on soda lime glass.

The single-sided release films of the double-sided adhesive sheets 1 to 16 were peeled off, roll-laminated to a PET film (Diafoil T100 manufactured by Mitsubishi Chemical Corporation, thickness 50 μm), and then cut to a width of 50 mm. After that, the release film on the other side is peeled off, rolled and bonded to soda lime glass so that the adhesive sheet is positioned between the electrodes, and then autoclaved (60°C, gauge pressure 0.2 MPa, 20 minutes) to finish. It was stuck.

For Examples 1 to 3, 5 to 6, and 8 to 10, and Comparative Examples 1 to 3 and 5 to 6, light was irradiated from the PET film side with a high-pressure mercury lamp so that the accumulated light amount at a wavelength of 365 nm was 2000 mJ/cm2. and photocured (post-cured product). Afterwards, a sample for evaluating Ag corrosion resistance was prepared by curing at room temperature for 12 hours.

For this sample, an environmental test was performed in a moist heat environment of 65°C, 90% RH x 300h, and an increase in the resistance value between electrodes was confirmed.

In the above environmental test, “× (poor)” indicates that the increase in resistance value exceeds 30%, “△ (usual)” indicates that the increase in resistance value exceeds 10% and is below 30%, and the increase in resistance value is suppressed to 10% or less. Those where the resistance value increase was suppressed to 2% or less were judged as “◎ (very good)”.

The evaluation results of examples and comparative examples are shown in Table 1.

In addition, in each example and comparative example in Table 1, the numerical value described in each item of the adhesive resin composition is a mass part.

The transparent double-sided adhesive sheets of Examples 1 to 10 were composed of a (meth)acrylic (co)polymer (A), a compound (B) having a radical polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule, and the (B) ) Since it is an adhesive sheet made of an adhesive resin composition containing an initiator (C) other than It was also excellent in corrosion resistance to metal components mainly used in transparent conductive layers, such as ITO, Cu, and Ag.

Among them, in Examples 2, 6, and 9, the foaming resistance reliability and durability were particularly improved by selecting the addition amount and type of compound (B) and initiator (C) other than (B), their use in combination with the rust preventive agent (D), etc. It was excellent in terms of metal corrosion resistance.

Examples 9 and 10 have excellent foaming resistance reliability and metal corrosion resistance by using an adhesive layer using the adhesive resin composition for the front and back layers, and an adhesive layer with a high crosslinking degree to which a crosslinking agent (E) is added is used for the middle layer, In addition, it was excellent in cutting processability and storage stability.

In contrast, in Comparative Examples 1, 2, and 5, a large amount of (hydrogen abstraction type) initiator was added, and the ultraviolet foaming resistance and metal corrosion resistance were inferior.

In addition, as in Comparative Example 3, if an attempt is made to reduce the amount of initiator added in an attempt to suppress ultraviolet foaming resistance or metal corrosion resistance, sufficient curing cannot be achieved during pre-curing or post-curing, the holding power decreases, and the cutting and workability decreases. It was inferior in storage stability, moist heat foaming resistance, and UV resistance foaming properties.

Additionally, in Comparative Example 4, a hydrogen abstraction type initiator and a cleavage type initiator were used together, but metal corrosion caused by the initiator or its residue could not be suppressed.

Additionally, in Comparative Example 6, compound (B) was used alone, but it could hardly be cured even when irradiated with light. If it was not used together with an initiator (C) other than (B), (B) would hardly function as an initiator.

Claims (20)

(meth)acrylic polymer or (meth)acrylic copolymer (A) (referred to as “(meth)acrylic (co)polymer (A)”), a radical polymerizable functional group having a carbon-carbon double bond and a radical generator are contained within the molecule. Branches include a compound (B) and an initiator (C) made of a compound other than the compound (B),
An adhesive resin composition characterized in that the content of the initiator (C) is 1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the compound (B). According to claim 1,
The compound (B) is an adhesive resin composition that is excited by irradiation of active energy rays and has a structure that generates radicals by generating a hydrogen abstraction reaction. According to claim 1,
The compound (B) has a (meth)acryloyl group, a benzophenone structure, a benzyl structure, an o-benzoylbenzoic acid ester structure, a thioxanthone structure, a 3-ketocoumarin structure, a 2-ethylanthraquinone structure, and camphorquinone. An adhesive resin composition, which is a compound having one structure or two or more structures. According to claim 1,
An adhesive resin composition in which the (meth)acrylic (co)polymer (A) does not contain or substantially does not contain a monomer having a carboxyl group. According to claim 1,
The (meth)acrylic (co)polymer (A) is an adhesive resin composition comprising a hydroxyl group-containing monomer and/or a nitrogen atom-containing monomer. According to claim 1,
An adhesive resin composition further comprising a rust inhibitor (D). According to claim 1,
An adhesive resin composition wherein the initiator (C) is a cleavage type photoinitiator. According to claim 1,
An adhesive resin composition wherein the total content of the compound (B) and the initiator (C) is 0.2 to 5 parts by mass based on 100 parts by mass of the (meth)acrylic (co)polymer (A). A pressure-sensitive adhesive sheet provided with an adhesive layer formed from the pressure-sensitive adhesive resin composition according to claim 1. A pressure-sensitive adhesive sheet provided with a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive resin composition according to claim 1, wherein the pressure-sensitive adhesive layer has active energy ray curability. According to claim 10,
An active energy ray-curable adhesive sheet containing a reaction decomposition product of the initiator (C). An optical member comprising a substrate having metal wiring on at least one side of the adhesive sheet according to claim 9 or the active energy ray-curable adhesive sheet according to claim 10 or 11. A laminate for an image display device having a structure in which the adhesive sheet according to claim 9 or the active energy ray-curable adhesive sheet according to claim 10 or 11 is interposed between two structural members for an image display device. According to claim 13,
At least one of the two image display device structural members is a laminate made of any of the group consisting of a touch sensor, an image display panel, a surface protection panel, a polarizing film, and a retardation film, or a combination of two or more types. Laminate for display device. An image display device provided with the laminate for an image display device according to claim 13. A compound (B) having a radically polymerizable functional group having a carbon-carbon double bond and a radical generator group in the molecule and an initiator (C) made of a compound other than the compound (B) are combined to form a (meth)acrylic (co)polymer. Use by mixing with (A),
A method of using compound (B) as an initiator, characterized in that the content of the initiator (C) is 1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the compound (B). According to claim 16,
A method of using compound (B), wherein the compound (B) is excited by irradiation of active energy rays and has a structure that generates radicals by generating a hydrogen abstraction reaction. The method of claim 16 or 17,
The compound (B) has a (meth)acryloyl group, a benzophenone structure, a benzyl structure, an o-benzoylbenzoic acid ester structure, a thioxanthone structure, a 3-ketocoumarin structure, a 2-ethylanthraquinone structure, and camphorquinone. Method of using compound (B), which is a compound having any one structure or two or more structures. The method of claim 16 or 17,
A method of using compound (B), wherein the initiator (C) is a cleavage type photoinitiator. The method of claim 16 or 17,
A method of using compound (B), wherein the total mixing amount of the compound (B) and the initiator (C) relative to 100 parts by mass of the (meth)acrylic (co)polymer (A) is 0.2 to 5 parts by mass.