TWI837777B - Adhesive composition, adhesive layer and optical member attached with the same - Google Patents

Abstract

The present application provides an adhesive composition, an adhesive layer comprising the adhesive composition, and an optical member attached with the adhesive layer comprising the adhesive composition. The adhesive composition contains: a (meth)acrylic resin (A) of 100 parts by weight, containing constituent unit of 3.5 wt % or less, derived from a (meth)acrylic monomer having a hydroxyl group, having a glass transition temperature of -25 ℃ or less; an aromatic isocyanate-based crosslinking agent (B) of 0.3-1 parts by weight; and a compound (C) containing at least one selected from an organic acid salt (C-1) and a compound containing an alkyleneoxy group (C-2); wherein the organic acid salt (C-1) is of 0.0001 to 5 parts by weight when being contained, and a compound containing an alkyleneoxy group (C-2) is of 0.1-5 parts by weight when being contained.

Description

Adhesive composition, adhesive layer, and optical component with adhesive layer attached

The present invention relates to an adhesive composition, an adhesive layer comprising the adhesive composition, and an optical component having the adhesive layer.

Polarizing plates formed by laminating protective films on one or both sides of polarizers are widely used in image display devices such as liquid crystal display devices and organic electroluminescent (organic EL) display devices, especially in recent years, optical components of various mobile devices such as mobile phones, smart phones, and tablet terminals. Optical components such as polarizing plates are mostly used by laminating to other components (such as optical components such as liquid crystal cells of liquid crystal display devices) through an adhesive layer (for example, refer to Japanese Patent Publication No. 2010-229321). Therefore, for example, polarizing plates are circulated on the market in the form of polarizing plates with adhesive layers pre-set on one side of the surface.

Adhesive compositions used in adhesive layers for bonding optical components are required to be durable. That is, adhesive layers bonded to optical components and built into image display devices are sometimes placed in high temperature or high temperature and high humidity environments, or in environments with repeated high and low temperatures. However, even in such environments, the adhesive layer is required to suppress defects caused by dimensional changes of adjacent optical components. Such defects include floating and peeling of the interface between the adhesive layer and the adjacent optical component, and bubbling of the adhesive layer.

However, conventional adhesive compositions sometimes have insufficient durability when bonded to optical components as adhesive layers, and the surface of the optical component to which the adhesive layer is bonded is difficult to be effectively activated even by surface activation treatment such as corona treatment, and in particular, the durability is sometimes insufficient.

The purpose of the present invention is to provide an adhesive composition having good durability when attached to an optical component surface as an adhesive layer, an adhesive layer including the adhesive composition, and an optical component having the adhesive layer, even if the surface of the optical component surface is not easily activated by surface activation treatment.

The present invention provides the adhesive composition, adhesive layer and optical component with adhesive layer as shown below.

[1] The adhesive composition includes:

100 parts by weight of a (meth)acrylic resin (A) containing a constituent unit derived from a (meth)acrylic monomer having a hydroxyl group in an amount of 3.5% by weight or less and having a glass transition temperature of -25°C or less;

Aromatic isocyanate crosslinking agent (B) 0.3 to 1 parts by weight; and

A compound (C) selected from at least one of an organic acid salt (C-1) and a compound (C-2) containing an alkoxy group;

When the aforementioned organic acid salt (C-1) is contained, its content is 0.0001 to 5 parts by weight relative to 100 parts by weight of the aforementioned (meth) acrylic resin (A),

When the aforementioned alkoxy-containing compound (C-2) is contained, its content is 0.1 to 5 parts by weight relative to 100 parts by weight of the aforementioned (meth)acrylic resin (A).

[2] The adhesive composition as described in [1], wherein the aforementioned alkoxy-containing compound (C-2) is a compound containing at least one double bond and at least one alkylenedioxy group in the molecule.

[3] An adhesive composition as described in [1] or [2], wherein the content of the constituent unit derived from the (meth) acrylic monomer having a hydroxyl group is 0.5% by weight or more.

[4] The adhesive composition described in any one of [1] to [3] further contains an ionic compound (D).

[5] The adhesive composition described in any one of [1] to [4] further contains a silane compound (E).

[6] An adhesive composition as described in any one of [1] to [5], wherein the adhesive composition is formed into a layer on a film composed of a cyclic polyolefin resin, the layered adhesive composition is layered on an alkali-free glass plate and stored at a temperature of 23°C for 24 hours, and the peeling force when peeling from the alkali-free glass plate is set to P(CO)23, and

The adhesive composition is formed into a layer on a film composed of a cyclic polyolefin resin, and the layered adhesive composition is laminated on an alkali-free glass plate and stored in an environment at a temperature of 50°C for 48 hours. When the peeling force when peeling from the alkali-free glass plate is set to P(CO)50, the ratio of the P(CO)50 to the P(CO)23 (P(CO)50/P(CO)23) is 3.2 or more.

[7] An adhesive composition as described in any one of [1] to [5], wherein the adhesive composition is formed into a layer on a film composed of a (meth) acrylic resin, the layered adhesive composition is layered on an alkali-free glass plate and stored at a temperature of 23°C for 24 hours, and the peeling force when peeling from the alkali-free glass plate is set to P(AC)23, and

The adhesive composition is formed into a layer on a film made of a (meth) acrylic resin, and the layered adhesive composition is laminated on an alkali-free glass plate and stored in an environment at a temperature of 50°C for 48 hours. When the peeling force when peeling from the alkali-free glass plate is set to P(AC)50, the ratio of the P(AC)50 to the P(AC)23 (P(AC)50/P(AC)23) is 3.2 or more.

[8] An adhesive composition as described in any one of [1] to [7], which contains the aforementioned organic acid salt (C-1) and the aforementioned compound containing an alkoxy group (C-2);

The content of the aforementioned organic acid salt (C-1) is 0.0001 to 0.1 parts by weight relative to 100 parts by weight of the aforementioned (meth) acrylic resin (A);

The content of the aforementioned alkoxy-containing compound (C-2) is 0.1 to 5 parts by weight relative to 100 parts by weight of the aforementioned (meth)acrylic resin (A).

[9] An adhesive layer comprising an adhesive composition described in any one of [1] to [8].

[10] An optical component with an adhesive layer, comprising an optical component and the adhesive layer described in [9] laminated on the optical component.

[11] An optical component with an adhesive layer as described in [10], wherein the contact angle variation rate of the surface of the optical component with the laminated adhesive layer is less than 40% when subjected to a corona treatment.

[12] An optical component with an adhesive layer as described in [11], wherein the optical component includes a polarizer and a protective film laminated on the polarizer, and the surface is the surface of the protective film.

[13] An optical component with an adhesive layer as described in [11] or [12], wherein the surface is a corona-treated surface.

[14] The optical component with an adhesive layer as described in any one of [11] to [13] further comprises a glass substrate laminated on the adhesive layer.

[15] An optical component with an adhesive layer, comprising a resin film and an adhesive layer laminated on at least one side of the resin film;

The aforementioned adhesive layer comprises an adhesive composition described in any one of [1] to [8];

The adhesive layer is deposited on an alkali-free glass plate and stored at a temperature of 23°C for 24 hours. The peeling force when peeling off the alkali-free glass plate is set to P23, and

When the adhesive layer is laminated on an alkali-free glass plate and stored at a temperature of 50°C for 48 hours, the peeling force when peeling from the alkali-free glass plate is set to P50, and the ratio of the P50 to the P23 (P50/P23) is 3.2 or more.

According to the present invention, an adhesive composition with good durability, an adhesive layer containing the adhesive composition, and an optical component having an adhesive layer attached thereto can be provided.

1: Polarizer

2: Surface treatment layer

3,4: Protective film

7: Phase difference film

8: Interlayer adhesive

10: Polarizing plate

20: Adhesive layer

25: Polarizing plate with adhesive layer

30: Glass Plate

Figure 1 is a schematic cross-sectional view showing an example of an optical component with an adhesive layer attached according to the present invention.

Figure 2 is a schematic cross-sectional view of another example of an optical component with an adhesive layer according to the present invention.

Figure 3 is a schematic cross-sectional view showing yet another example of an optical component with an adhesive layer attached according to the present invention.

Figure 4 is a schematic cross-sectional view showing yet another example of an optical component with an adhesive layer attached according to the present invention.

〈Adhesive composition〉

[1] (Meth) acrylic resin (A)

The (meth)acrylic resin (A) is a polymer containing a constituent unit derived from a (meth)acrylic monomer having a hydroxyl group, and preferably contains the following formula (I) in addition to the constituent unit:

The polymer shown is mainly composed of a structural unit derived from (meth)acrylate. In this specification, "(meth)acrylic acid" refers to acrylic acid and/or methacrylic acid, and "(meth)" when referring to (meth)acrylate, etc., has the same meaning.

In the above formula (I), ^R1 represents a hydrogen atom or a methyl group, and ^R2 represents an alkyl group having 1 to 14 carbon atoms which may be substituted by an alkoxy group having 1 to 10 carbon atoms, or an aralkyl group having 7 to 21 carbon atoms which may be substituted by an alkoxy group having 1 to 10 carbon atoms. Preferably ^{, R2} is an alkyl group having 1 to 14 carbon atoms which may be substituted by an alkoxy group having 1 to 10 carbon atoms.

As the (meth)acrylate represented by formula (I), for example, alkyl (meth)acrylate, specific examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-octyl (meth)acrylate, and lauryl (meth)acrylate, wherein the alkyl portion of which is a straight chain; and isopropyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and isooctyl (meth)acrylate, wherein the alkyl portion of which is a branched chain. The carbon number of the alkyl portion of the alkyl (meth)acrylate is preferably 1 to 8, and more preferably 1 to 6.

When R ² is an alkyl group substituted by an alkoxy group, that is, when R ² is an alkoxyalkyl group, specific examples of the (meth)acrylate represented by formula (I) include 2-methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, etc. The carbon number of the alkyl group of the above alkoxyalkyl group is preferably 1 to 8, more preferably 1 to 6. The carbon number of the alkoxy group of the above alkoxyalkyl group is preferably 1 to 8, more preferably 1 to 4. Specific examples of the (meth)acrylate represented by formula (I) when R ² is an aralkyl group having 7 to 21 carbon atoms include benzyl (meth)acrylate. The carbon number of the above aralkyl group is preferably 7 to 11.

The (meth)acrylate represented by formula (I) may be used alone or in combination of two or more. The (meth)acrylate preferably includes an alkyl (meth)acrylate, more preferably includes an alkyl acrylate, and even more preferably includes n-butyl acrylate. The (meth)acrylic resin (A) preferably includes 50% by weight of n-butyl acrylate in all the constituent units thereof. Of course, in addition to n-butyl acrylate, other (meth)acrylates represented by formula (I) may also be used in combination.

The content of the constituent units derived from the (meth)acrylate represented by formula (I) is usually 60% by weight or more and less than 100% by weight, preferably 70 to 99.9% by weight, and more preferably 80 to 99.6% by weight, in all the constituent units constituting the (meth)acrylic resin (A).

The (meth)acrylic resin (A) contains a constituent unit derived from a (meth)acrylic monomer having a hydroxyl group. The inclusion of the constituent unit is advantageous in improving the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer. The (meth)acrylic monomer having a hydroxyl group is preferably a (meth)acrylate having a hydroxyl group. Specific examples of (meth)acrylates having a hydroxyl group include alkyl esters of (meth)acrylic acid containing a hydroxyl group such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-(2-hydroxyethoxy)ethyl (meth)acrylate, 2- or 3-chloro-2-hydroxypropyl (meth)acrylate, and partial esters of (meth)acrylic acid with multifunctional alcohols such as diethylene glycol mono(meth)acrylate. From the viewpoint of the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer (especially heat resistance), the monomer having a hydroxyl group is preferably a (meth)acrylate having a hydroxyl group, and more preferably an alkyl ester of (meth)acrylate containing a hydroxyl group. The carbon number of the alkyl part of the alkyl ester of (meth)acrylate containing a hydroxyl group is preferably 1 to 8, and more preferably 1 to 6.

The content of the constituent units derived from the (meth)acrylic monomer having a hydroxyl group is 3.5% by weight or less, preferably 3% by weight or less, more preferably 2.5% by weight or less, and even more preferably 2% by weight or less, in all the constituent units constituting the (meth)acrylic resin (A). When the content of the constituent units derived from the (meth)acrylic monomer having a hydroxyl group exceeds 3.5% by weight, the durability of the adhesive layer, especially the heat resistance, is insufficient. On the other hand, the content of the constituent units derived from the (meth)acrylic monomer having a hydroxyl group is usually 0.1% by weight or more, preferably 0.2% by weight or more, and even more preferably 0.5% by weight or more. When the content of the constituent unit derived from the (meth) acrylic monomer having a hydroxyl group is less than 0.1% by weight, the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer are insufficient.

The (meth)acrylic resin (A) may contain a constituent unit derived from a monomer having other polar functional groups other than the (meth)acrylic monomer having a hydroxyl group. The monomer having a polar functional group is preferably a (meth)acrylic monomer having a polar functional group. Examples of the polar functional group possessed by the monomer include a carboxyl group (free carboxyl group), an amine group, a heterocyclic group (e.g., an epoxy group), and the like.

Specific examples of monomers having other polar functional groups include (meth)acrylic acid, (meth)acrylic acid β-carboxyethyl ester, monomers having carboxyl groups; acrylamide, vinyl caprolactam, N-vinyl-2-pyrrolidone, vinylpyridine, tetrahydrofuranmethyl (meth)acrylate, caprolactone-modified tetrahydrofuranmethyl (meth)acrylate, (meth)acrylate 3,4-epoxycyclohexylmethyl ester, (meth)acrylate glycidyl, 2,5-dihydrofuran, monomers having heterocyclic groups; (meth)acrylic acid aminoethyl ester, (meth)acrylic acid N,N-dimethylaminoethyl ester, (meth)acrylic acid dimethylaminopropyl ester, etc. Monomers having other polar functional groups may be used alone or in combination of two or more.

In addition to (meth)acrylic monomers having hydroxyl groups, monomers having other polar functional groups are used in combination. Among them, (meth)acrylic monomers having carboxyl groups are advantageous in improving the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer (especially heat resistance).

The content of the constituent units derived from monomers having other polar functional groups, preferably (meth)acrylic monomers having carboxyl groups, in all the constituent units constituting the (meth)acrylic resin (A) is preferably 5% by weight or less, and more preferably 4% by weight or less. When the content of the constituent units derived from monomers having other polar functional groups exceeds 5% by weight, the durability of the adhesive layer, especially the heat resistance, tends to be insufficient. On the other hand, the content of the constituent units derived from monomers having other polar functional groups, when contained, is generally 0.1% by weight or more, preferably 0.2% by weight or more, and more preferably 0.3% by weight or more. When the content of the constituent units derived from monomers having other polar functional groups is less than 0.1% by weight, it is difficult to see the effect of use. The constituent units of all monomers having polar functional groups derived from (meth) acrylic monomers having hydroxyl groups are generally 0.1 to 8.5% by weight, preferably 0.2 to 7% by weight, in the total constituent units constituting the (meth) acrylic resin (A).

The (meth)acrylic resin (A) may also further include constituent units from monomers having one olefinic double bond and at least one aromatic ring in the molecule (but other than the monomers represented by the above formula (I) or the above monomers having polar functional groups). As a suitable example, a (meth)acrylic monomer having an aromatic ring can be cited. Such (meth)acrylic monomers having an aromatic ring also include neopentyl glycol benzoate (meth)acrylate, etc., especially the following formula (II):

The (meth)acrylate containing phenoxyethyl group shown is preferably a (meth)acrylate having an aromatic oxyalkyl group. Monomers having one olefinic double bond and at least one aromatic ring in the molecule of (meth)acrylate containing phenoxyethyl group, etc., can be used alone or in combination of two or more.

In the above formula (II), R ³ represents a hydrogen atom or a methyl group, n represents an integer from 1 to 8, and R ⁴ represents a hydrogen atom, an alkyl group, an aralkyl group, or an aromatic group. When R ⁴ is an alkyl group, the carbon number thereof may be about 1 to 9, when it is an aralkyl group, the carbon number thereof may be about 7 to 11, or when it is an aromatic group, the carbon number thereof may be about 6 to 10.

Examples of the alkyl group having 1 to 9 carbon atoms constituting ^R4 in formula (II) include methyl, butyl, nonyl, etc., examples of the aralkyl group having 7 to 11 carbon atoms include benzyl, phenethyl, naphthylmethyl, etc., and examples of the aromatic group having 6 to 10 carbon atoms include phenyl, tolyl, naphthyl, etc.

Specific examples of (meth)acrylates containing phenoxyethyl groups represented by formula (II) include 2-phenoxyethyl (meth)acrylate, 2-(2-phenoxyethoxy)ethyl (meth)acrylate, ethylene oxide-modified nonylphenol (meth)acrylate, 2-(o-phenylphenoxy)ethyl (meth)acrylate, etc. Among them, (meth)acrylates containing phenoxyethyl groups include 2-phenoxyethyl (meth)acrylate, 2-(o-phenylphenoxy)ethyl (meth)acrylate and/or 2-(2-phenoxyethoxy)ethyl (meth)acrylate.

The content of the constituent units derived from monomers having an aromatic ring is generally 0 to 20% by weight (e.g., 6 to 12% by weight) in all the constituent units constituting the (meth)acrylic resin (A). However, in order to make the glass transition temperature of the (meth)acrylic resin (A) within the specified range described below, it is sometimes preferred not to contain constituent units derived from monomers having an aromatic ring.

The (meth)acrylic resin (A) may also contain constituent units from monomers other than the (meth)acrylic monomer represented by formula (I) described above, monomers having polar functional groups, and monomers having aromatic rings (hereinafter also referred to as other monomers). Specific examples of other monomers include constituent units from (meth)acrylic monomers having alicyclic structures in the molecule (preferably (meth)acrylates having alicyclic structures in the molecule), constituent units from styrene monomers, constituent units from vinyl monomers, constituent units from monomers having multiple (meth)acryl groups in the molecule, constituent units from (meth)acrylamide compounds, and the like. Other monomers may be used alone or in combination of two or more.

The alicyclic structure of the (meth)acrylate having an alicyclic structure in the molecule refers to a cycloalkane structure with a carbon number of usually 5 or more, preferably 5 to 7 or so. Specific examples of (meth)acrylate having an alicyclic structure include isoborneol (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, cyclododecyl (meth)acrylate, methylcyclohexyl (meth)acrylate, trimethylcyclohexyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, cyclohexylphenyl (meth)acrylate, α-ethoxycyclohexyl acrylate, etc.

Specific examples of styrene monomers include styrene; alkyl styrenes such as methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, and octyl styrene; halogenated styrenes such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, and iodostyrene; nitrostyrene, acetylstyrene, methoxystyrene, divinylbenzene, etc.

Specific examples of vinyl monomers include fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, and vinyl laurate; halogenated vinyls such as vinyl chloride and vinyl bromide; halogenated vinyls such as vinyl chloride; nitrogen-containing aromatic vinyls such as vinyl pyridine, vinyl pyrrolidone, and vinyl carbazole; conjugated diene monomers such as butadiene, isoprene, and chloroprene; acrylonitrile, methacrylonitrile, etc.

Specific examples of monomers having multiple (meth)acryloyl groups in the molecule include monomers having two (meth)acryloyl groups in the molecule such as 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate; and monomers having three (meth)acryloyl groups in the molecule such as trihydroxymethylpropane tri(meth)acrylate.

Specific examples of the (meth)acrylamide compound include N-hydroxymethyl (meth)acrylamide, N-(2-hydroxyethyl) (meth)acrylamide, N-(3-hydroxypropyl) (meth)acrylamide, N-(4-hydroxybutyl) (meth)acrylamide, N-(5-hydroxypentyl) (meth)acrylamide, N-(6-hydroxyhexyl) (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, N-isopropyl ...4-hydroxybutyl) (meth)acrylamide, N-(4-hydroxybutyl) (meth)acrylamide, N-(4-hydroxybutyl) ( Acrylamide, N-(3-dimethylaminopropyl)(methyl)acrylamide, N-(1,1-dimethyl-3-oxybutyl)(methyl)acrylamide, N-[2-(2-oxy-1-imidazolidinyl)ethyl](methyl)acrylamide, 2-acrylamino-2-methyl-1-propanesulfonic acid, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)(methyl)acrylamide, N-(propoxymethyl)(methyl)acrylamide, N-(1 -methylethoxymethyl)(methyl)acrylamide, N-(1-methylpropoxymethyl)(methyl)acrylamide, N-(2-methylpropoxymethyl)(methyl)acrylamide [alias: N-(isobutoxymethyl)(methyl)acrylamide], N-(butoxymethyl)(methyl)acrylamide, N-(1,1-dimethylethoxymethyl)(methyl)acrylamide, N-(2-methoxyethyl)(methyl)acrylamide, N-(2-ethoxyethyl)(methyl)acrylamide, N- (2-propoxyethyl) (methyl) acrylamide, N-[2-(1-methylethoxy) ethyl] (methyl) acrylamide, N-[2-(1-methylpropoxy) ethyl] (methyl) acrylamide, N-[2-(2-methylpropoxy) ethyl] (methyl) acrylamide [alias: N-(2-isobutoxyethyl) (methyl) acrylamide], N-(2-butoxyethyl) (methyl) acrylamide, N-[2-(1,1-dimethylethoxy) ethyl] (methyl) acrylamide, etc. Among them, N-(methoxymethyl) acrylamide, N-(ethoxymethyl) acrylamide, N-(propoxymethyl) acrylamide, N-(butoxymethyl) acrylamide, and N-(2-methylpropoxymethyl) acrylamide are preferably used.

The (meth)acrylic resin (A) generally contains 0 to 20% by weight, preferably 0 to 10% by weight, of the constituent units of the (meth)acrylic resin (A).

The adhesive composition may contain two or more (meth)acrylic resins belonging to the (meth)acrylic resin (A). Furthermore, the adhesive composition may also contain other (meth)acrylic resins different from the (meth)acrylic resin (A). Examples of other (meth)acrylic resins are (meth)acrylic resins having constituent units from a (meth)acrylic monomer represented by formula (I) and having no polar functional groups. However, the adhesive composition preferably contains the (meth)acrylic resin (A) as the main component, and the content of the (meth)acrylic resin (A) is preferably 60% by weight or more, more preferably 80% by weight or more, and even more preferably 90% by weight or more in the total of all (meth)acrylic resins.

The glass transition temperature (Tg) of the (meth)acrylic resin (A) measured by a differential scanning calorimeter (DSC) is below -25°C, preferably below -30°C. The adhesive composition of the present invention containing the (meth)acrylic resin (A) having a Tg of below -25°C can improve the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer. From the perspective of durability, the Tg of the (meth)acrylic resin (A) is usually above -55°C, preferably above -50°C.

Furthermore, according to the adhesive composition of the present invention containing a (meth) acrylic resin (A) having a Tg of -25°C or less, it is possible to shorten the aging time of the adhesive layer. That is, in order to obtain a suitable degree of operability and processability, the adhesive layer (adhesive sheet) is generally aged, and according to the adhesive composition of the present invention, the aging time of the adhesive layer required for the crosslinking reaction to fully proceed can be shortened.

The (meth)acrylic resin (A) preferably has a weight average molecular weight (Mw) in the range of 500,000 to 2,000,000, and more preferably 600,000 to 1,800,000, as measured by gel permeation chromatography (GPC) in terms of standard polystyrene. When the Mw is 500,000 or more, the adhesion between the adhesive layer and the optical component in a high temperature and high humidity environment is improved, the possibility of floating or peeling between the adhesive layer and the optical component tends to be reduced, and the reworkability of the adhesive layer tends to be improved. Moreover, when the Mw is less than 2 million, when the adhesive layer is attached to the optical component, even if the size of the optical component changes, the adhesive layer can easily move to follow the size change, which is advantageous in terms of the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer. Moreover, due to the above-mentioned tracking property, when the optical component with the adhesive layer is applied to a liquid crystal display device, the difference between the brightness of the peripheral part and the brightness of the central part of the liquid crystal unit will disappear, and there is a tendency to suppress whitening and color unevenness. The molecular weight distribution shown by the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is usually about 2 to 10, preferably 3 to 7.

(Meth)acrylic resin (A) and other (meth)acrylic resins that can be used in combination can be produced by known methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization. In the production of (meth)acrylic resin, a polymerization initiator can usually be used. The polymerization initiator can be used in an amount of about 0.001 to 5 parts by weight relative to a total of 100 parts by weight of all monomers used in the production of the (meth)acrylic resin. In addition, the (meth)acrylic resin can also be produced by a method in which it is polymerized by active energy rays such as ultraviolet rays.

As the polymerization initiator, a thermal polymerization initiator or a photopolymerization initiator can be used. As the photopolymerization initiator, for example, 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone can be used. As the thermal polymerization initiator, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethyl-4-methoxyvaleronitrile), dimethyl-2,2'-azobis(2-methylpropionate), 2,2'-azobis(2-hydroxymethylpropionitrile) ) azo compounds; organic peroxides such as lauryl peroxide, 3-butyl peroxide, benzoyl peroxide, 3-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, dipropyl peroxydicarbonate, 3-butyl peroxyneodecanoate, 3-butyl peroxypivalate, (3,5,5-trimethylhexyl) peroxide; inorganic peroxides such as potassium persulfate, ammonium persulfate, and hydrogen peroxide. In addition, redox initiators using peroxides and reducing agents can also be used as polymerization initiators.

As a method for manufacturing (meth) acrylic resin, the solution polymerization method is preferred among the methods shown above. An example of the solution polymerization method is to mix the monomers used with an organic solvent, add a thermal polymerization initiator in a nitrogen environment, and stir for about 3 to 15 hours at about 40 to 90°C, preferably about 50 to 80°C. In order to control the reaction, the monomers and thermal polymerization initiators can be added continuously or intermittently during the polymerization, or they can be added in a state dissolved in an organic solvent. As an organic solvent, for example, aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propanol and isopropanol; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone can be used.

[2] Aromatic isocyanate crosslinking agent (B)

The adhesive composition may further contain an aromatic isocyanate crosslinking agent (B). The aromatic isocyanate crosslinking agent (B) is a compound having an aromatic ring and having two or more isocyanate groups in the molecule. By using an aromatic isocyanate compound (B) as a crosslinking agent, the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer can be improved.

Specific examples of aromatic isocyanate crosslinking agents (B) include cresyl diisocyanate, chlorocresyl diisocyanate, diphenylmethane diisocyanate, cresyl diisocyanate, polymethylene polyphenyl isocyanate, naphthyl diisocyanate, etc. In addition, aromatic isocyanate crosslinking agents (B) include polyol adducts of such isocyanate compounds (e.g., adducts of trihydroxymethylpropane), isocyanurates, biuret-type compounds, and derivatives of polyurethane polymer-type isocyanate compounds that undergo addition reactions with polyether polyols, polyester polyols, acrylic polyols, polybutadiene polyols, polyisoprene polyols, etc. Aromatic isocyanate crosslinking agents (B) may be used alone or in combination of two or more.

Among the aromatic isocyanate crosslinking agents (B), aromatic isocyanate crosslinking agents in which the isocyanate group is bonded to an aromatic ring are preferably used to effectively improve the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer. Specific examples of aromatic isocyanate crosslinking agents in which the isocyanate group is bonded to an aromatic ring include cresyl diisocyanate, chlorocresyl diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, naphthyl diisocyanate, etc.

The content of the aromatic isocyanate crosslinking agent (B) is 0.3 to 1 part by weight, preferably 0.35 to 0.9 part by weight, based on 100 parts by weight of the (meth) acrylic resin (A). When the content of the aromatic isocyanate crosslinking agent (B) is less than 0.3 parts by weight, the adhesion between the adhesive layer and the optical component becomes insufficient even after sufficient aging time, depending on the surface material of the optical component on which the adhesive layer is laminated. In addition, the durability of the adhesive layer when attached to the optical component is reduced, depending on the surface material of the optical component on which the adhesive layer is laminated. When the content of the aromatic isocyanate crosslinking agent (B) exceeds 1 part by weight, the adhesion between the adhesive layer and the optical component becomes insufficient even after sufficient aging time. In addition, the durability, especially the heat resistance, of the adhesive layer when attached to the optical component is reduced.

〔3〕Compound (C)

The adhesive composition further contains at least one compound (C) selected from an organic acid salt (C-1) and a compound (C-2) containing an alkoxy group. According to the adhesive composition of the present invention containing compound (C), the adhesion between the adhesive layer and the optical component can be improved, and the durability of the adhesive layer when attached to the optical component, especially the heat resistance, can be improved. In addition, the aging time of the adhesive layer can be shortened. The adhesive composition can contain only an organic acid salt (C-1), only an alkoxy group-containing compound (C-2), or both.

The organic acid salt (C-1) is preferably a salt composed of an organic acid having a carboxylic acid terminal and a base, that is, an organic carboxylate salt. When an organic carboxylate salt is used as the organic acid salt (C-1), the relative cation of the carboxylate anion is preferably a relative cation of trivalence or less. The organic acid salt (C-1) may be used alone or in combination of two or more.

As the above-mentioned relative cations, for example, metal ions, ammonium ions, cations with a heterocyclic structure, etc. Preferred examples of metal ions include alkali metal ions and alkali earth metal ions. Preferred examples of cations with a heterocyclic structure include pyrrolinium ions, imidazolium ions, triazolium ions, pyrrolidinium ions, pyridinium ions, and piperidinium ions.

As carboxylate anions of organic acid salts (C-1), for example, straight-chain saturated and alkyl carboxylate anions such as formic acid ions, acetic acid ions, propionic acid ions, heptanoic acid ions, octanoic acid ions, and lauric acid ions; straight-chain unsaturated and alkyl carboxylate anions such as (meth) acrylic acid and oleic acid; aromatic carboxylate anions such as benzoic acid and cinnamic acid; carboxylate anions with a heterocyclic structure such as nicotinic acid; dicarboxylate anions such as succinic acid, fumaric acid, and phthalic acid; carboxylate anions with an oxyethylene skeleton such as 2-(2-ethoxy)ethoxycarboxylate anions, etc.

The content of the organic acid salt (C-1) is 0.0001 to 5 parts by weight relative to 100 parts by weight of the (meth) acrylic resin (A), preferably 0.0005 to 5 parts by weight, more preferably 0.0007 to 3 parts by weight, even more preferably 0.001 to 1 part by weight, and particularly preferably 0.0015 to 0.5 parts by weight. As long as the content is within this range, the adhesive composition can be obtained with good adhesion between the adhesive layer and the optical component, good durability when the adhesive layer is attached to the optical component, and shortened aging time of the adhesive layer.

The compound (C-2) containing an alkoxy group is preferably a compound containing at least one double bond and at least one alkylenedioxy group in the molecule. The alkylenedioxy group is preferably contained in the compound (C-2) as an alkylenedioxy group (-O-alkylenedioxy group). A preferred example of the above double bond is a double bond contained in a (meth)acryloyl group. The compound (C-2) containing an alkoxy group may be used alone or in combination of two or more. The adhesive layer composed of the adhesive composition containing the compound (C-2) containing an alkoxy group can also suppress the peeling force of the peeling film deposited on the surface of the adhesive layer from being accelerated by heat.

Preferred examples of the alkylenedioxy group are alkylenedioxy groups having 1 to 4 carbon atoms, more preferably linear or branched alkylenedioxy groups having 1 to 3 carbon atoms, and even more preferably ethylenedioxy groups (-OC 2 H 4 -O-), from the viewpoint of the adhesion between the adhesive layer and the optical member and the durability when the adhesive layer is attached to the optical member. The same is true for examples of alkoxy groups other than the _{alkylenedioxy} group, and the alkoxy group is preferably _an alkoxy group having 1 to 4 carbon atoms, more preferably a linear or branched alkoxy group having 1 to 3 carbon atoms, and even more preferably ethylenedioxy groups (-OC ₂ H ₄ -).

From the perspective of adhesion between the adhesive layer and the optical component, and durability when the adhesive layer is bonded to the optical component, the compound (C-2) comprises the following formula (C-2a):

The compound (C-2a) containing a (meth)acryloyl group is preferred, and the compound (C-2a) is more preferred. In the formula, h represents an integer from 1 to 6, ^Q1 represents a hydrogen atom or a methyl group, and ^Q0 represents an H-valent group having at least one alkylenedioxy group. The compound (C-2) may contain two or more compounds (C-2a), and h is preferably an integer from 1 to 3.

The H-valent group having at least one alkylenedioxy group represented by ^Q0 may be an H-valent alkyl group having at least one alkylenedioxy group, and is preferably a 1- to 3-valent alkyl group having at least one alkylenedioxy group. Examples of the alkyl group include the groups represented by ^Q01 , ^Q02 , ^Q03 and ^Q04 described below.

In Q ⁰¹ , Q ² represents an alkyl group, an aromatic group or an aralkyl group having 1 to 4 carbon atoms which may be substituted with an alkoxy group having 1 to 3 carbon atoms, L represents a single bond or an alkylene group having 1 to 4 carbon atoms, and i represents an integer of 1 to 50 (e.g., 1 to 30). The number of carbon atoms of the aromatic group which may become Q ² is preferably 6 to 20, and the number of carbon atoms of the aralkyl group is preferably 7 to 20. In Q ⁰² , j represents an integer of 1 to 40 (e.g., 1 to 30). In Q ⁰³ , y and z each independently represent an integer of 1 to 40 (e.g., 1 to 30), and y+z may be an integer of 1 to 40 (e.g., 1 to 30). In Q ⁰⁴ , e, f and g each independently represent an integer of 1 to 20 (e.g., 1 to 10), and e+f+g may be an integer of 1 to 30 (e.g., 1 to 25).

The compound (C-2a) preferably used is, for example, the following formula (C-2a-1):

The compound (C-2a-1) shown. Compound (C-2) may contain more than two kinds of compounds (C-2a-1). Compound (C-2a-1) is a compound wherein Q ⁰ in the above formula (C-2a) is Q ^01. In the formula, Q ¹ , L, i, and Q ² represent the same meanings as described above. In compound (C-2a-1), L is preferably a single bond, and i is preferably an integer from 7 to 35, and more preferably an integer from 9 to 25. Q ² is preferably an alkyl group having 1 to 3 carbon atoms or an aromatic group having 6 to 20 carbon atoms. Specific examples of Q ² include methyl, ethyl, n-propyl, isopropyl, phenyl, and biphenyl.

Specific examples of compound (C-2a-1) include Q ¹ , L, i, and Q ² as shown in Table 1 below.

Another example of the compound (C-2a) preferably used is a compound wherein ^Q0 in the above formula (C-2a) is ^Q04 . In this case, h in the above formula (C-2a) is 3. Compound (C-2) may contain two or more compounds wherein ^Q0 is ^Q04 . In ^Q04 , e+f+g is preferably an integer of 5 to 25.

Another example of the compound (C-2a) preferably used is a compound wherein ^Q0 in the above formula (C-2a) is ^Q03 . In this case, h in the above formula (C-2a) is 2. Compound (C-2) may contain two or more compounds wherein ^Q0 is ^Q034 . In ^Q03 , y+z is preferably an integer of 5 to 25.

The content of compound (C-2) is 0.1 to 5 parts by weight, preferably 0.15 to 5 parts by weight, more preferably 0.2 to 4.5 parts by weight, and even more preferably 0.5 to 4 parts by weight, relative to 100 parts by weight of (meth) acrylic resin (A). As long as the content is within this range, the adhesive layer can have good adhesion to the optical component, the durability of the adhesive layer when attached to the optical component is good, and the aging time of the adhesive layer can be shortened, and the effect of promoting the suppression of peeling force can be obtained.

〔4〕Ionic compounds (D)

The adhesive composition may further contain an ionic compound (D) as an antistatic agent to impart antistatic properties to the adhesive layer. The ionic compound (D) is a compound having an inorganic cation or an organic cation and an inorganic anion or an organic anion. Two or more ionic compounds (D) may be used.

Examples of the inorganic cations include alkali metal ions such as lithium cation [Li ⁺ ], sodium cation [Na ⁺ ], and potassium cation [K ⁺ ], and alkali earth metal ions such as palladium cation [Be ²⁺ ], magnesium cation [Mg ²⁺ ], and calcium cation [Ca ²⁺ ].

Examples of organic cations include imidazolium cations, pyridinium cations, pyrrolidinium cations, ammonium cations, sulfonium cations, and phosphonium cations.

Among the above cationic components, organic cationic components are preferred due to their excellent compatibility with the adhesive composition. Among the organic cationic components, pyridinium cations and imidazolium cations are particularly preferred because the peeling film disposed on the adhesive layer is not easily charged during peeling.

Examples of the inorganic anion include chlorine anion [Cl ^- ], bromine anion [Br ^- ], iodine anion [I ^- ], tetrachloroaluminate anion [AlCl ₄ ^- ], heptachloroaluminate anion [Al ₂ Cl ₇ ^- ], tetrafluoroborate anion [BF ₄ ^- ], hexafluorophosphate anion [PF ₆ ^- ], perchlorate anion [ClO ₄ ^- ], nitrate anion [NO ₃ ^- ], hexafluoroarsenate anion [AsF ₆ ^- ], hexafluoroantimonate anion [SbF ₆ ^- ], hexafluoroniobate anion [NbF ₆ ^- ], and the like. 〕, hexafluorotantalum anion〔TaF ₆ ^- 〕, dicyanamide anion〔(CN) ₂ N ^- 〕, etc.

Examples of the organic anion include acetate anion [CH ₃ COO ^- ], trifluoroacetate anion [CF ₃ COO ^- ], methanesulfonate anion [CH ₃ SO ₃ ^- ], trifluoromethanesulfonate anion [CF ₃ SO ₃ ^- ], p-toluenesulfonate anion [p-CH ₃ C ₆ H ₄ SO ₃ ^- ], bis(fluorosulfonyl)imide anion [(FSO ₂ ) ₂ N ^- ], bis(trifluoromethanesulfonyl)imide anion [(CF ₃ SO ₂ ) ₂ N ^- ], tris(trifluoromethanesulfonyl)methanide anion [(CF ₃ SO ₂ ) ₃ C ^- ], dimethylphosphinate anion [(CH ₃ ) ₂ POO ^- ], polyhydrofluorinated fluoride anion [F(HF) _n ^- ] (n is about 1 to 3), thiocyanate anion [SCN ^- ], perfluorobutanesulfonate anion [C ₄ F ₉ SO ₃ ^{- ]} , bis(pentafluoroethanesulfonyl)imide anion [(C ₂ F ₅ SO ₂ ) ₂ N ^- ], perfluorobutyrate anion [C ₃ F ₇ COO ^- ], (trifluoromethanesulfonyl)(trifluoromethanecarbonyl)imide anion [(CF ₃ SO ₂ )(CF ₃ CO) N ^- ], perfluoropropane-1,3-disulfonate anion [ ^- O ₃ S(CF ₂ ) ₃ SO ₃ ^- ], carbonate anion [CO ₃ ^2- 〕wait.

Among the above-mentioned anionic components, anionic components containing fluorine atoms are particularly preferred because they can provide an ionic compound (D) with excellent antistatic function. Specifically, for example, bis(fluorosulfonyl)imide anions, hexafluorophosphate anions, or bis(trifluoromethanesulfonyl)imide anions.

Specific examples of the ionic compound (D) can be appropriately selected from the above-mentioned combination of cationic components and anionic components. When the examples of the ionic compound (D) having organic cations are disclosed by classifying them into the structure of the organic cations, for example, those shown below are shown.

Pyridinium salt:

N-Hexylpyridinium hexafluorophosphate,

N-octylpyridinium hexafluorophosphate,

N-octyl-4-methylpyridinium hexafluorophosphate,

N-butyl-4-methylpyridinium hexafluorophosphate,

N-decylpyridinium bis(fluorosulfonyl)imide,

N-dodecylpyridinium bis(fluorosulfonyl)imide,

N-Tetradecylpyridinium bis(fluorosulfonyl)imide,

N-hexadecylpyridinium bis(fluorosulfonyl)imide,

N-dodecyl-4-methylpyridinium bis(fluorosulfonyl)imide,

N-Tetradecyl-4-methylpyridinium bis(fluorosulfonyl)imide,

N-hexadecyl-4-methylpyridinium bis(fluorosulfonyl)imide,

N-Benzyl-2-methylpyridinium bis(fluorosulfonyl)imide,

N-Benzyl-4-methylpyridinium bis(fluorosulfonyl)imide,

N-hexylpyridinium bis(trifluoromethanesulfonyl)imide,

N-octylpyridinium bis(trifluoromethanesulfonyl)imide,

N-octyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide,

N-Butyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide.

Imidazolium salt:

1-Ethyl-3-methylimidazolium hexafluorophosphate,

1-Ethyl-3-methylimidazolium p-toluenesulfonate,

1-Ethyl-3-methylimidazolium bis(fluorosulfonyl)imide,

1-Ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide,

1-Butyl-3-methylimidazolium methanesulfonate,

1-Butyl-3-methylimidazolium bis(fluorosulfonyl)imide.

Pyrrolidinium salt:

N-butyl-N-methylpyrrolidinium hexafluorophosphate,

N-butyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide,

N-Butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide.

Level 4 ammonium salt:

Tetrabutylammonium hexafluorophosphate,

Tetrabutylammonium p-toluenesulfonate,

(2-Hydroxyethyl)trimethylammonium bis(trifluoromethanesulfonyl)imide,

(2-Hydroxyethyl)trimethylammonium dimethylphosphinate.

Furthermore, when citing examples of ionic compounds (D) having inorganic cations, for example, those shown below are given.

Lithium bromide,

Lithium iodide,

Lithium tetrafluoroborate,

Lithium hexafluorophosphonate,

Lithium thiocyanate,

Lithium perchlorate,

Lithium trifluoromethanesulfonate,

Lithium bis(fluorosulfonyl)imide,

Lithium bis(trifluoromethanesulfonyl)imide,

Lithium bis(pentafluoroethanesulfonyl)imide,

Lithium tris(trifluoromethanesulfonyl)methanide,

Lithium p-toluenesulfonate,

Sodium hexafluorophosphate,

Sodium bis(fluorosulfonyl)imide,

Sodium bis(trifluoromethanesulfonyl)imide,

Sodium p-toluenesulfonate,

Potassium hexafluorophosphate,

Potassium bis(fluorosulfonyl)imide,

Potassium bis(trifluoromethanesulfonyl)imide,

Potassium p-toluenesulfonate.

The ionic compound (D) is preferably solid at room temperature. Compared with the case where an ionic compound (D) is liquid at room temperature, the antistatic function can be maintained for a longer period of time. From the perspective of long-term stability of such antistatic properties, the ionic compound (D) preferably has a melting point of 30°C or more, and preferably 35°C or more. On the other hand, if the melting point is too high, the compatibility with the (meth) acrylic resin (A) deteriorates, and the melting point is preferably below 90°C, more preferably below 70°C, and even more preferably below 50°C.

The content of the ionic compound (D) in the adhesive composition is preferably 0.2 to 8 parts by weight, more preferably 0.2 to 5 parts by weight, more preferably 0.3 to 5 parts by weight, and particularly preferably 0.5 to 3 parts by weight relative to 100 parts by weight of the (meth) acrylic resin (A). A content of the ionic compound (D) of 0.2 parts by weight or more is beneficial for improving the anti-static function, and a content of 8 parts by weight or less is beneficial for maintaining the durability of the adhesive layer.

〔5〕Silane compounds (E)

The adhesive composition may further contain a silane compound (E). This can improve the adhesion between the adhesive layer and optical components such as glass substrates.

Examples of the silane compound (E) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycyrrhizic acid propyltrimethoxysilane, 3-glycyrrhizic acid propylmethyldimethoxysilane, 2-(3,4-Epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-butylenepropyltrimethoxysilane, 3-glycyrrhetinylpropyltrimethoxysilane, 3-glycyrrhetinylpropyltriethoxysilane, 3-glycyrrhetinylpropyldimethoxymethylsilane, 3-glycyrrhetinylpropylethoxydimethylsilane, etc. Two or more silane compounds may be used.

The silane compound (E) may also be a polysiloxane oligomer. When the polysiloxane oligomer is represented in the form of a (monomer) oligomer, for example, as shown below.

3-butylpropyltrimethoxysilane-tetramethoxysilane copolymer,

3-Hydroxypropyltrimethoxysilane-tetraethoxysilane copolymer,

3-butylpropyltriethoxysilane-tetramethoxysilane copolymer,

3-Benzylpropyltriethoxysilane-tetraethoxysilane copolymer and other Benzylpropyl copolymers;

Methyltrimethoxysilane-tetramethoxysilane copolymer,

Methyltrimethoxysilane-tetraethoxysilane copolymer,

Methyltriethoxysilane-tetramethoxysilane copolymer,

Copolymers containing methylbenzene, such as methylbenzene triethoxysilane-tetraethoxysilane copolymer;

3-Epoxypropylpropyltrimethoxysilane-tetramethoxysilane copolymer,

3-Epoxypropylpropyltrimethoxysilane-tetraethoxysilane copolymer,

3-Epoxypropylpropyltriethoxysilane-tetramethoxysilane copolymer,

3-Epoxypropylpropyltriethoxysilane-tetraethoxysilane copolymer,

3-Epoxypropylpropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-Epoxypropylpropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-Epoxypropylpropylmethyldiethoxysilane-tetramethoxysilane copolymer,

Copolymers containing 3-glycidylpropyl groups, such as 3-glycidylpropylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-Methacryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,

3-Methacryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,

3-Methacryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,

3-Methacryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,

3-Methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-Methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-Methacryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,

Copolymers containing methacryloyloxypropyl such as 3-methacryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-Acryloxypropyltrimethoxysilane-tetramethoxysilane copolymer,

3-Acryloxypropyltrimethoxysilane-tetraethoxysilane copolymer,

3-Acryloxypropyltriethoxysilane-tetramethoxysilane copolymer,

3-Acryloxypropyltriethoxysilane-tetramethoxysilane copolymer,

3-Acryloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-Acryloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-Acryloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,

Copolymers containing acryloxypropyl groups, such as 3-acryloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

Vinyltrimethoxysilane-tetramethoxysilane copolymer,

Vinyltrimethoxysilane-tetraethoxysilane copolymer,

Vinyl triethoxysilane-tetramethoxysilane copolymer,

Vinyl triethoxysilane-tetraethoxysilane copolymer,

Vinylmethyldimethoxysilane-tetramethoxysilane copolymer,

Vinylmethyldimethoxysilane-tetraethoxysilane copolymer,

Vinylmethyldiethylmethoxysilane-tetramethoxysilane copolymer,

Copolymers containing vinyl groups, such as vinylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer,

3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer,

3-aminopropyltriethoxysilane-tetramethoxysilane copolymer,

3-aminopropyltriethoxysilane-tetraethoxysilane copolymer,

3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer,

3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer,

3-aminopropylmethyldiethylmethoxysilane-tetramethoxysilane copolymer,

Copolymers containing amine groups such as 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer, etc.

Most of the silane compounds (E) exemplified above are liquid. The content of the silane compound (E) in the adhesive composition is 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, and more preferably 0.2 to 0.4 parts by weight, relative to 100 parts by weight of the (meth)acrylic resin (A). When the amount of the silane compound (E) is 0.01 parts by weight or more, it is easy to obtain an effect of improving the adhesion between the adhesive layer and optical components such as glass substrates. Moreover, when the content is 10 parts by weight or less, the permeation of the silane compound (E) from the adhesive layer can be suppressed.

[6] Other ingredients

The adhesive composition may contain additives such as crosslinking catalysts, weathering stabilizers, thickeners, plasticizers, softeners, dyes, pigments, inorganic fillers, light scattering microparticles, and resins other than (meth) acrylic resins (A). In addition, after the adhesive composition is mixed with a UV-curable compound and the adhesive layer is formed, it is irradiated with UV rays to cure it, which can also be used to form a harder adhesive layer. As a crosslinking catalyst, amine compounds such as hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, polyamine resins, and melamine resins can be used.

(Adhesive layer)

The adhesive layer of the present invention includes the adhesive composition of the present invention, and is typically composed of the adhesive composition of the present invention. The adhesive layer is obtained by dissolving or dispersing the components constituting the adhesive composition in a solvent to form an adhesive composition containing a solvent, and then applying the adhesive composition containing a solvent on a substrate film and drying it. The adhesive layer of the present invention has excellent adhesion and durability, and can shorten the required aging time.

The substrate film is generally a plastic film, and a typical example thereof is a release film (separation film) subjected to release treatment. The release film may be subjected to release treatment such as silicone treatment on the surface formed by the adhesive layer of a film composed of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polyarylate. For example, an adhesive composition may be directly applied to the release-treated surface of the release film to form an adhesive layer, and an optical component with an adhesive layer may be obtained by laminating the adhesive layer with the release film on the optical component. Furthermore, an adhesive layer is formed by directly coating the adhesive composition on the surface of the optical component, and a film is peeled off on the outer surface of the adhesive layer as needed to form an optical component with an adhesive layer. When the adhesive layer is provided on the surface of the optical component, it is preferred to perform plasma treatment, corona treatment, etc. on the bonding surface of the optical component and/or the bonding surface of the adhesive layer, and it is more preferred to perform corona treatment.

The thickness of the adhesive layer is preferably 10 to 45 μm, more preferably 10 to 30 μm, and even more preferably 15 to 25 μm. When the thickness of the adhesive layer is within this range, it is beneficial to the adhesion between the adhesive layer and the optical component and the durability of the adhesive layer when it is attached to the optical component. For the same reason, the gel ratio is preferably in the range of 30 to 85%.

The adhesive composition of the present invention is formed into a layer on a film composed of a cyclic polyolefin resin, and the layered adhesive composition is layered on an alkali-free glass plate and stored at a temperature of 23°C for 24 hours. The peeling force when peeling the layered adhesive composition and the film composed of the cyclic polyolefin resin from the alkali-free glass plate is set to P(CO)23, and

The layered adhesive composition is formed into a layer on a film composed of a cyclic polyolefin resin, and the layered adhesive composition is deposited on an alkali-free glass plate and stored at a temperature of 50°C for 48 hours. When the peeling force when peeling the layered adhesive composition and the film composed of the cyclic polyolefin resin from the alkali-free glass plate is set to P(CO)50,

The ratio of the aforementioned P(CO)50 to the aforementioned P(CO)23 (P(CO)50/P(CO)23) is preferably 3.2 or more, more preferably 3.5 or more, and even more preferably 3.8 or more. When an optical component comprising a film composed of a cyclic polyolefin resin is bonded to a liquid crystal unit made of inorganic glass on the film side through an adhesive layer comprising such an adhesive composition, the optical component can be peeled off immediately after bonding and re-bonded to a new optical component, that is, the reworkability is good. At the same time, by heating after bonding, the peeling force is increased, and the optical component can be bonded to the liquid crystal unit more firmly, which is preferred.

Furthermore, in the adhesive composition of the present invention, it is formed into a layer on a film composed of a (meth) acrylic resin, and the layered adhesive composition is laminated on an alkali-free glass plate and stored in an environment at a temperature of 23°C for 24 hours. The peeling force when peeling the layered adhesive composition and the film composed of the cyclic polyolefin resin from the alkali-free glass plate is set to P(AC)23, and

The layered adhesive composition is formed into a layer on a film composed of a (meth) acrylic resin, and the layered adhesive composition is deposited on an alkali-free glass plate and stored at a temperature of 50°C for 48 hours. When the peeling force when peeling the layered adhesive composition and the film composed of the cyclic polyolefin resin from the alkali-free glass plate is set to P(AC)50,

The ratio of the aforementioned P(AC)50 to the aforementioned P(AC)23 (P(AC)50/P(AC)23) is preferably 3.2 or more, more preferably 3.5 or more, and even more preferably 3.8 or more. When an optical component comprising a film composed of a (meth) acrylic resin is bonded to a liquid crystal unit made of inorganic glass on the film side through an adhesive layer comprising such an adhesive composition, the optical component can be peeled off immediately after bonding and re-bonded to a new optical component, that is, the reworkability is good. At the same time, by heating after bonding, the peeling force is increased, and the optical component can be bonded to the liquid crystal unit more firmly, which is preferred.

The aforementioned P(CO)23 or P(AC)23 is preferably 0.3 to 5N/25mm, more preferably 0.5 to 5N/25mm, and even more preferably 0.5 to 3N/25mm. When P(CO)23 or P(AC)23 is within this range, the reworkability and adhesion to the liquid crystal unit are good. Moreover, the aforementioned P(CO)50 or P(AC)50 is preferably 1 to 15N/25mm, more preferably 1.5 to 15N/25mm, and even more preferably 2 to 13N/25mm. When P(CO)50 or P(AC)50 is within this range, the reworkability and adhesion to the liquid crystal unit are good.

The adhesive composition of the present invention contains an organic acid salt (C-1) and a compound (C-2). The content of the organic acid salt (C-1) is 0.0001 to 0.1 parts by weight, preferably 0.0005 to 0.05 parts by weight, and preferably 0.001 to 0.02 parts by weight relative to 100 parts by weight of the (meth) acrylic resin (A). The content of the compound (C-2) is 0.1 to 5 parts by weight, preferably 0.15 to 4 parts by weight, and preferably 0.2 to 3 parts by weight relative to 100 parts by weight of the (meth) acrylic resin (A).

By containing the above-mentioned amount of organic acid salt (C-1) and compound (C-2), the ratio of the aforementioned P(CO)50 to the aforementioned P(CO)23 (P (CO)50/P(CO)23) can be easily adjusted to preferably 3.2 or more, more preferably 3.5 or more, and even more preferably 3.8 or more.

Furthermore, by containing the above-mentioned amount of organic acid salt (C-1) and compound (C-2), the ratio of the aforementioned P(AC)50 to the aforementioned P(AC)23 (P(AC)50/P(AC)23) can be easily adjusted to preferably 3.2 or more, more preferably 3.5 or more, and even more preferably 3.8 or more.

〈Optical components with adhesive layer〉

The adhesive layer of the present invention can be used as an adhesive layer for bonding components to each other, especially optical components to each other. The optical component with the adhesive layer of the present invention, for example, can be laminated on a certain optical component, and other optical components can be laminated on the outside of the adhesive layer.

[1] The first implementation form

A preferred embodiment of the optical component with adhesive layer of the present invention includes a resin film as an optical component and an adhesive layer laminated on at least one side thereof. The resin film can be, for example, an optical film attached to a polarizer, a protective film, a phase difference film, etc., or an optical film of a protected body, etc., and is a surface protective film (protective film) used for the purpose of protecting the surface from damage or contamination.

A polarizer is a film that has the function of extracting linear polarized light from incident natural light. A suitable example is a uniaxially stretched polyvinyl alcohol resin film adsorbed and aligned with a dichroic pigment such as iodine or a dichroic dye. The thickness of the polarizer is not particularly limited, but is usually 0.5 to 35 μm.

The protective film can be a light-transmitting (preferably optically transparent) resin, such as a polyolefin resin such as a chain polyolefin resin (polypropylene resin, etc.), a cyclic polyolefin resin (norbornene resin, etc.); a cellulose resin such as triacetyl cellulose and diacetyl cellulose; a polyester resin; a polycarbonate resin; a (meth) acrylic resin; a polystyrene resin; a polyether acetyl ketone resin; a film made of a thermoplastic resin such as a polyester resin. .

As chain polyolefin resins, in addition to single polymers of chain olefins such as polyethylene resins and polypropylene resins, copolymers composed of two or more chain olefins can be cited.

Cyclic polyolefin resins are a general term for resins that use cyclic olefins as polymerized units. Specific examples of cyclic polyolefin resins include ring-opening (co)polymers of cyclic olefins, addition polymers of cyclic olefins, copolymers of cyclic olefins and chain olefins such as ethylene and propylene (representatively random copolymers), and graft polymers modified with unsaturated carboxylic acids or their derivatives, and hydrogenated products thereof. Among them, norbornene resins using norbornene monomers such as norbornene or polycyclic norbornene monomers as cyclic olefins are preferred.

The cellulose resin is a partially or completely esterified product of cellulose, such as cellulose acetate, propionate, butyrate, and mixed esters thereof. Among them, triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, cellulose acetate butyrate, etc. are preferably used.

Polyester resins are resins other than the above-mentioned cellulose resins having ester bonds, and are generally composed of condensates of polycarboxylic acids or their derivatives and polyols. As polycarboxylic acids or their derivatives, dicarboxylic acids or their derivatives can be used, such as terephthalic acid, isophthalic acid, dimethyl terephthalate, dimethyl naphthalene dicarboxylate, etc. As polyols, diols can be used, such as ethylene glycol, propylene glycol, butanediol, neopentyl glycol, cyclohexane dimethanol, etc.

Specific examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexane dimethyl terephthalate, and polycyclohexane dimethyl naphthalate.

Polycarbonate resins are composed of polymers with monomer units linked via carbonate groups. Polycarbonate resins can also be modified polycarbonates or copolymerized polycarbonates, etc.

The (meth)acrylic resin can be a polymer with methacrylate as the main monomer, preferably a copolymer with a small amount of other copolymer monomer components. The (meth)acrylic resin is more preferably a copolymer of methyl methacrylate and methyl acrylate, and can also be copolymerized with a third functional monomer.

As the third functional monomer, for example, methacrylates other than methyl methacrylate such as ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, and 2-hydroxyethyl methacrylate; acrylates other than methyl acrylate such as ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl acrylate; 2-(hydroxymethyl) methyl acrylate, Hydroxyl alkyl acrylates such as methyl 2-(1-hydroxyethyl)acrylate, ethyl 2-(hydroxymethyl)acrylate, and butyl 2-(hydroxymethyl)acrylate; unsaturated acids such as methacrylic acid and acrylic acid; halogenated styrenes such as chlorostyrene and bromostyrene; substituted styrenes such as vinyltoluene and α-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; unsaturated anhydrides such as maleic anhydride and maleic methyl maleic anhydride; unsaturated imides such as phenylmaleimide and cyclohexylmaleimide, etc. The third functional monomer can be used alone or in combination of two or more.

The (meth)acrylic resin can be further copolymerized with a multifunctional monomer. The multifunctional monomer includes ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, nonaethylene glycol di(meth)acrylate, tetradecaethylene glycol di(meth)acrylate, ethylene glycol or oligomer thereof whose two terminal hydroxyl groups are esterified with acrylic acid or methacrylic acid; propylene glycol or oligomer thereof whose two terminal hydroxyl groups are esterified with acrylic acid or methacrylic acid; divalent alcohol such as neopentyl glycol di(meth)acrylate, hexanediol di(meth)acrylate, butanediol di(meth)acrylate whose hydroxyl groups are esterified with acrylic acid or methacrylic acid; Phenol A, bisphenol A epoxy adducts or halogen substituted products thereof, both terminal hydroxyl groups of which are esterified with acrylic acid or methacrylic acid; polyols such as trihydroxymethylpropane and pentaerythritol esterified with acrylic acid or methacrylic acid, and epoxy groups of glycidyl acrylate or glycidyl methacrylate are added to the terminal hydroxyl groups; epoxy groups of glycidyl acrylate or glycidyl methacrylate are added to succinic acid, adipic acid, terephthalic acid, phthalic acid, dibasic acids of halogen substituted products thereof, and epoxy adducts thereof; aromatic (meth)acrylates; aromatic divinyl compounds such as divinylbenzene, etc. Among them, ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and neopentyl glycol di(meth)acrylate are preferably used.

(Meth) acrylic resins may be modified by further reacting the functional groups of the copolymer. Such reactions include, for example, a polymer chain demethylation condensation reaction between the methyl group of methyl acrylate and the hydroxyl group of methyl 2-(hydroxymethyl)acrylate, and a polymer chain dehydration condensation reaction between the carboxyl group of acrylic acid and the hydroxyl group of methyl 2-(hydroxymethyl)acrylate. In addition, (meth) acrylic resins may have any structure of a glutarimide derivative, a glutaric anhydride derivative, or a lactone ring structure.

(Meth) acrylic resins may contain additives as needed. Additives include lubricants, anti-caking agents, heat stabilizers, antioxidants, antistatic agents, light-resistant agents, impact resistance improvers, surfactants, etc.

(Meth) acrylic resins may contain acrylic rubber particles from the viewpoint of film-forming properties and impact resistance of the film. The so-called acrylic rubber particles refer to particles in which an elastic polymer mainly composed of acrylic ester is an essential component, such as a single-layer structure substantially composed of the elastic polymer alone, and a multi-layer structure in which the elastic polymer is one layer. Examples of the elastic polymer include crosslinked elastic copolymers in which an alkyl acrylate is a main component and other vinyl monomers and crosslinking monomers can be copolymerized therewith. The alkyl acrylate that is the main component of the elastic polymer, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, etc., has an alkyl group with a carbon number of about 1 to 8, and acrylic acid having an alkyl group with a carbon number of 4 or more is particularly preferred. As other vinyl monomers copolymerizable with the alkyl acrylate, for example, compounds having one polymerizable carbon-carbon double bond in the molecule, more specifically, methacrylates such as methyl methacrylate, aromatic vinyl compounds such as styrene, vinyl cyanide compounds such as acrylonitrile, etc. As crosslinking monomers, for example, crosslinking compounds having at least two polymerizable carbon-carbon double bonds in the molecule, more specifically, (meth)acrylates of polyols such as ethylene glycol di(meth)acrylate and butanediol di(meth)acrylate, (meth)acrylates such as allyl (meth)acrylate, divinylbenzene, etc.

A laminate of a film composed of a (meth) acrylic resin containing no rubber particles and a film composed of a (meth) acrylic resin containing rubber particles may be used as a protective film.

The phase difference film is an optical film showing optical anisotropy. In addition to the resins used in the above-mentioned protective film, the phase difference film can be a stretched film obtained by stretching a resin film composed of a polyvinyl alcohol resin, a polyarylate resin, a polyimide resin, a polyether sulfone resin, a polyvinylidene fluoride/polymethyl methacrylate resin, a liquid crystal polyester resin, an ethylene-vinyl acetate copolymer saponification product, a polyvinyl chloride resin, etc. to about 1.01 to 6 times. Among them, a stretched film of a polycarbonate resin film, a cyclic polyolefin resin film, a (meth) acrylic resin film or a cellulose resin film stretched in one axis or two axes is preferred. Moreover, in this specification, the phase difference film also includes a zero retardation film (however, the zero retardation film can also be used as a protective film). In addition, films called uniaxial phase difference films, wide viewing angle phase difference films, low light elasticity phase difference films, etc. may also be used as phase difference films.

The so-called zero hysteresis film refers to a film with an in-plane phase difference value _Re and a thickness direction phase difference value _Rth of -15 to 15nm. The phase difference film is suitable for use in IPS (in-plane switching) mode liquid crystal display devices. The in-plane phase difference value _Re and the thickness direction phase difference value _Rth are preferably -10 to 10nm, and more preferably -5 to 5nm. The in-plane phase difference value _Re and the thickness direction phase difference value _Rth here refer to the values at a wavelength of 590nm.

The in-plane phase difference value _Re and the thickness direction phase difference value _Rth are respectively expressed as follows:

_Re =( _nx - _ny )×d

_Rth is defined as [( _nx + _ny )/2- _nz ]×d. In the formula, _nx is the refractive index in the direction of the delayed phase axis (x-axis direction) in the film plane, _ny is the refractive index in the direction of the forward phase axis (y-axis direction perpendicular to the x-axis in the plane), _nz is the refractive index in the thickness direction (z-axis direction perpendicular to the film plane), and d is the thickness of the film.

For the zero hysteresis film, for example, a resin film composed of polyolefin resins such as cellulose resins, chain polyolefin resins and cyclic polyolefin resins, polyethylene terephthalate or (meth)acrylic resins can be used. In particular, since the phase difference value is easy to control and obtain, it is better to use cellulose resins, polyolefin resins or (meth)acrylic resins. For example, a phase difference display layer composed of a resin different from (meth)acrylic resin and having a (meth)acrylic resin layer laminated on one or both sides can be used as a phase difference film.

Furthermore, films that exhibit optical anisotropy by coating/alignment of liquid crystal compounds or films that exhibit optical anisotropy by coating of inorganic layered compounds can also be used as phase difference films. Such phase difference films include those called temperature compensation phase difference films, films with tilted alignment of rod-shaped liquid crystals sold by JX Nippon Mining & Petrochemical Co., Ltd. under the trade name "NH FILM", films with tilted alignment of discotic liquid crystals sold by Fuji Film Co., Ltd. under the trade name "WV FILM", films with complete biaxial alignment sold by Sumitomo Chemical Co., Ltd. under the trade name "VAC FILM", and films with biaxial alignment sold by Sumitomo Chemical Co., Ltd. under the trade name "new VAC FILM".

On the other hand, the surface protection film is a film used to protect the surface of the optical film of the protected body from damage and contamination. For example, various optical films such as polarizers, protective films, phase difference films, light diffusion films, and reflective films used in liquid crystal display devices are usually circulated with the surface protection film attached to their surface (when there is an adhesive layer on one side, the surface opposite to the adhesive layer). The surface protection film is generally peeled off and removed after the above optical film is attached to the liquid crystal unit, etc.

As the substrate of the surface protective film, for example, polyolefin resins such as polyethylene, polypropylene, and polymethylpentene; fluorinated polyolefin resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyvinyl fluoride; polyester resins such as polyethylene naphthalate, polyethylene terephthalate, polybutylene terephthalate, and polyethylene terephthalate/isophthalate copolymer; polyamides such as nylon 6 and nylon 6,6; polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, and ethylene-vinyl acetate; Ethylene ester copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, vinyl polymer of vinyl (vinylon); cellulose resin of triacetyl cellulose, diacetyl cellulose, cellophane (cellophane); (meth) acrylic resin of polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate; other films composed of thermoplastic resins such as polystyrene, polycarbonate, polyarylate, polyimide, etc. The optical component with adhesive layer of the present invention, in which the resin film is a surface protective film, is provided with an adhesive layer on the substrate.

In the optical component with adhesive layer of this embodiment, the above-mentioned peeling film is attached to the surface of the adhesive layer for better temporary protection until use. The optical component with adhesive layer of this embodiment with peeling film attached can be manufactured by coating an adhesive composition on the peeling film to form an adhesive layer, and then depositing a resin film on the obtained adhesive layer, or by coating an adhesive composition on a resin film to form an adhesive layer, and then attaching a peeling film to the adhesive surface.

The optical component with adhesive layer in this embodiment is

When the adhesive layer is laminated on an alkali-free glass plate and stored at a temperature of 23°C for 24 hours, the peeling force when peeled off from the alkali-free glass plate is P23, and

By forming this adhesive layer, when it is layered on an alkali-free glass plate and stored at a temperature of 50°C for 48 hours, when the peeling force when peeling from the alkali-free glass plate is P50,

The ratio of P50 to P23 (P50/P23) is 3.2 or more, 3.5 or more, and especially 3.8 or more. The so-called reworkability becomes good, and the peeling force is increased by heating after bonding, so the optical component can be more firmly bonded to the liquid crystal unit, so it is better.

The aforementioned P23 is preferably 0.3 to 5N/25mm, more preferably 0.5 to 5 N/25mm, and even more preferably 0.5 to 3N/25mm. When P23 is within this range, the reworkability and adhesion to the liquid crystal unit become good. Moreover, the aforementioned P50 is preferably 1 to 15N/25mm, more preferably 1.5 to 15N/25mm, and even more preferably 2 to 13N/25mm. When P50 is within this range, the reworkability and adhesion to the liquid crystal unit become good.

[2] Second implementation form

Another preferred embodiment of the optical component with adhesive layer of the present invention comprises a laminate of resin film and an adhesive layer laminated on at least one side thereof. The laminate of resin film is preferably a laminate of optical film selected from polarizer, protective film, phase difference film and the like. A representative example of the laminate of optical film is polarizing plate. In the optical component with adhesive layer of this embodiment, a release film is preferably attached to the surface of the adhesive layer for temporary protection until use.

As polarizing plates, for example, there are linear polarizing plates that absorb linear polarized light with a vibration plane in a certain direction of the incident film surface and transmit linear polarized light with a vibration plane perpendicular to the incident film surface; polarizing separators that reflect linear polarized light with a vibration plane in a certain direction of the incident film surface and transmit linear polarized light with a vibration plane perpendicular to the incident film surface; and elliptical polarizing plates with a phase difference film laminated on a linear polarizing plate.

The linear polarizing plate generally has a structure in which the protective film is laminated to one or both sides of the polarizer. When the protective film is laminated to both sides of the polarizer, an adhesive layer is formed on the surface of at least one side of the protective film. When the protective film is laminated to only one side of the polarizer, an adhesive layer can be formed on the surface of the polarizer (the side without the protective film laminated). The elliptical polarizing plate is a phase difference film laminated on the linear polarizing plate, but the linear polarizing plate generally has the same structure as above. When the adhesive layer is laminated on the elliptical polarizing plate, the adhesive layer is usually laminated on the phase difference film side.

A specific example of an optical component with an adhesive layer when the optical component is a polarizing plate is described with reference to the drawings. In the example shown in FIG. 1, a protective film 3 having a surface treatment layer 2 is attached to a single surface of a polarizing plate 1 with the surface opposite to the surface treatment layer 2 to form a polarizing plate 10. An adhesive layer 20 is provided on the surface opposite to the protective film 3 of the polarizing plate 1 to form a polarizing plate with an adhesive layer (optical component with an adhesive layer) 25. The adhesive layer 20 can be attached to a glass substrate 30 on the surface opposite to the polarizing plate 10. The glass substrate 30 will be described later.

The optical component 25 with adhesive layer shown in FIG. 2 is the same as FIG. 1 except that the polarizing plate 10 includes the second protective film 4 attached to the surface of the other side of the polarizing plate 1. The adhesive layer 20 is laminated on the outside of the second protective film 4. The optical component 25 with adhesive layer shown in FIG. 3 is the same as FIG. 1 except that the polarizing plate 10 includes the phase difference film 7 attached to the surface of the other side of the polarizing plate 1 via the interlayer adhesive 8. The optical component 25 with adhesive layer shown in FIG. 4 is the same as FIG. 2 except that the polarizing plate 10 includes the phase difference film 7 attached to the outside of the second protective film 4 via the interlayer adhesive 8. In the examples shown in FIG. 3 and FIG. 4, the adhesive layer 20 is attached to the phase difference film 7.

The surface treatment layer 2 formed on the surface of the protective film 3 may be a hard coating layer, an anti-glare layer, an anti-reflection layer, an anti-static layer, etc. Among them, a plurality of layers may be provided. As shown in the examples of FIG. 3 and FIG. 4, when the polarizing plate 10 includes a phase difference film 7, in the case of small and medium-sized liquid crystal display devices, a suitable example of the phase difference film 7 is, for example, a 1/4 wavelength plate. In this case, the absorption axis of the polarizing plate 1 and the delayed phase axis of the phase difference film 7 are generally configured to intersect at about 45 degrees, and depending on the characteristics of the liquid crystal unit, the angle may deviate to a certain extent from 45 degrees. On the other hand, in the case of large liquid crystal display devices such as televisions, the phase difference compensation or viewing angle compensation of the liquid crystal unit is for the purpose, and the phase difference film 7 with various phase difference values can be used in accordance with the characteristics of the liquid crystal unit. In this case, the absorption axis of the polarizer 1 and the delayed phase axis of the phase difference film 7 are generally arranged in an approximately perpendicular or parallel relationship. When the phase difference film 7 is composed of a 1/4 wavelength plate, it is suitable to use a one-axis or two-axis stretched film. Moreover, for the purpose of phase difference compensation or viewing angle compensation of the liquid crystal unit, when the phase difference film 7 is set, in addition to the one-axis or two-axis stretched film, in addition to the one-axis or two-axis stretched film, the film is also oriented in the thickness direction, and the film is coated on the support film with a phase difference-detecting substance such as liquid crystal and fixedly oriented, which is called an optical compensation film, can also be used as the phase difference film 7.

The interlayer adhesive 8 in Figures 3 and 4 is generally a general (meth) acrylic adhesive, but the adhesive layer of the present invention can also be used. In the case of the large liquid crystal display device described above, when the absorption axis of the polarizer 1 and the delayed phase axis of the phase difference film 7 are arranged in an approximately perpendicular or parallel relationship, an adhesive can be used instead of the interlayer adhesive 8. As an adhesive, for example, a water-based adhesive that is composed of an aqueous solution or a water dispersion and exhibits adhesiveness by evaporating water as a solvent, and an ultraviolet-curing adhesive that hardens and exhibits adhesiveness by ultraviolet irradiation. The bonding of the polarizer 1 and the protective films 3, 4 is also usually performed using an adhesive.

With regard to the optical component with adhesive layer of the present invention, since the adhesive layer includes the adhesive composition of the present invention, the adhesive layer and the optical component have good adhesion and durability. According to the present invention, even if the surface of the optical component to which the adhesive layer is bonded is a surface that is difficult to activate by conventional surface activation treatment such as corona treatment or plasma treatment, an optical component with adhesive layer having good adhesion and durability between the adhesive layer and the optical component can be obtained. Here, the surface that is difficult to activate by surface activation treatment refers to, for example, a surface whose contact angle variation rate during corona treatment is less than 40% and less than 30%. The contact angle variation rate is usually above 0.1%, preferably above 0.5%.

The contact angle change rate is given by the following formula:

Contact angle change rate (%) = {(contact angle before corona treatment - contact angle after corona treatment) / contact angle after corona treatment} × 100. The so-called contact angle after corona treatment refers to the contact angle after the surface is subjected to one corona treatment at an output of 0.3kW and a line speed of 10m/min and then placed in an environment of temperature 23°C and relative humidity 60% for 24 hours. The contact angle is the contact angle to water and the unit is "°".

The contact angle variation rate during the above-mentioned corona treatment varies depending on the constituent material of the surface of the optical component. Thermoplastic resins with a contact angle variation rate of less than 40% include (meth) acrylic resins, cellulose resins, polyester resins, polycarbonate resins, etc. The surface of the optical component formed by these thermoplastic resins can be the surface of an optical film such as a protective film or a phase difference film.

[3] The third implementation form

Another preferred embodiment of the optical component with adhesive layer of the present invention is to laminate and bond other optical components on the outside of the adhesive layer in the optical component with adhesive layer of the first or second embodiment. The other optical component is suitable for a glass substrate. Figures 1 to 4 show the polarizing plate with adhesive layer of the second embodiment bonded to the glass substrate 30.

The glass substrate 30 may be a glass substrate for a liquid crystal unit, anti-glare glass, or glass for sunglasses. The material of the glass substrate 30 may be sodium calcium glass, low-alkali glass, or alkali-free glass. The glass substrate is preferably a glass substrate for a liquid crystal unit.

Polarizing plates are usually laminated on both sides of a liquid crystal cell with adhesive layers interposed therebetween. However, among these polarizing plates, only the polarizing plate disposed on the front side (identification side) of the liquid crystal cell is the optical component with adhesive layer of the present invention, or only the polarizing plate disposed on the back side (backlight side) of the liquid crystal cell is the optical component with adhesive layer of the present invention, or both of them are the optical components with adhesive layer of the present invention. The driving method of the liquid crystal cell can be any conventionally known method. The polarizing plate disposed on the back side (backlight side) usually does not have a surface treatment layer 2. On the outside of the polarizing plate disposed on the back side, various optical films such as a brightness enhancement film, a light focusing film, and a diffusion film, which are known to be disposed on the back side of the liquid crystal unit, can be disposed.

Optical components with adhesive layers such as polarizing plates with adhesive layers can be used in liquid crystal display devices. Liquid crystal display devices can be used, for example, as personal computers including notebooks, desktops, PDAs (personal digital assistants), various mobile devices such as smart phones and tablet terminals, televisions, car displays, electronic dictionaries, digital cameras, digital video cameras, electronic desktop computers, clocks, etc.

[Implementation example]

The following are examples and comparative examples to more specifically illustrate the present invention, but the present invention is not limited to these examples. The following refers to the amount and percentage of the content, which are based on weight unless otherwise specified.

<Production Examples 1 to 7: Production of (meth) acrylic resin for adhesive layer>

In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, a monomer mixture having the monomer composition shown in Table 2 (weight % when the total amount of monomers is 100 weight %) and diluted with ethyl acetate was placed, and after replacing the air in the apparatus with nitrogen to make it oxygen-free, the internal temperature was raised to 55°C. Then, the entire amount of a solution in which azobisisobutyronitrile (polymerization initiator) was dissolved in ethyl acetate was added. After adding the initiator, the temperature was maintained for 1 hour, and then ethyl acetate was continuously added to the reaction vessel while maintaining the internal temperature at 54 to 56°C until the concentration of the (meth)acrylic resin reached 35 weight %, at which time the addition of ethyl acetate was stopped and the temperature was maintained until 12 hours from the time when the addition of ethyl acetate was started. Finally, ethyl acetate was added to adjust the concentration of the (meth)acrylic resin to 20% by weight to prepare an ethyl acetate solution of the (meth)acrylic resin.

The weight average molecular weight (Mw) and glass transition temperature (Tg) of the obtained (meth) acrylic resin were measured. Mw was measured by converting to standard polystyrene at a temperature of 40°C and a flow rate of 1 mL/min using tetrahydrofuran as the eluent, a sample concentration of 5 mg/mL, and a sample introduction volume of 100 μL, with a total of 5 columns connected in series in a GPC apparatus as columns. Tg was measured using a differential scanning calorimeter (DSC) "EXSTAR DSC 6000" manufactured by SII Nanotech, in a nitrogen environment, at a temperature range of -80 to 50°C and a heating rate of 10°C/min. The monomer composition (weight %) of the monomer mixture used and the Mw and Tg of the obtained (meth)acrylic resin are summarized in Table 2.

The abbreviations in the "Monomer Composition" column of Table 2 refer to the following monomers.

BA: n-butyl acrylate

EHA: 2-ethylhexyl acrylate

MA: Methyl acrylate

AA: Acrylic acid

HEA: 2-Hydroxyethyl acrylate

〈Examples 1 to 10, Comparative Examples 1 to 8〉

(1) Preparation of adhesive composition

With respect to 100 parts by weight of the solid content of the (meth) acrylic resin (A) obtained in the above production example, the crosslinking agent (B), compound (C) and silane compound (E) shown in Table 2 were mixed in the amounts (parts by weight) shown in Table 3, and ethyl acetate was added to make the solid content concentration become 14% by weight to prepare a solution of the adhesive composition. The amount of each formulation component shown in Table 3 is the weight percentage of the active ingredient contained therein when the product used contains a solvent, etc.

In Table 3, the details of each blending ingredient represented by abbreviated names are as follows.

B1: Ethyl acetate solution of trihydroxymethylpropane adduct of cresyl diisocyanate (solid content concentration 75%), "CORONATE L" obtained from Nippon Polyurethane Co., Ltd.,

B2: Hexamethylene diisocyanate isocyanurate, liquid with about 100% active ingredient, "CORONATE HXR" obtained from Nippon Polyurethane Co., Ltd.

C1: Sodium acetate: obtained from Wako Junyaku Industries (in the adhesive composition, it is dissolved in ethanol and added to prepare a 0.5 wt% solution.)

C2: "AM-130G" acquired by Shin-Nakamura Chemical Industry Co., Ltd. (the following formula:

Methoxylated polyethylene glycol acrylate shown),

S1: 3-Epoxypropylpropyltrimethoxysilane, "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(2) Preparation of adhesive layer

Each adhesive composition prepared in the above (1) was applied to the release-treated surface of a release film made of polyethylene terephthalate (PLR-382051 obtained from LINTEC, also called a release film) using an applicator to a thickness of 20 μm after drying, and dried at 100°C for 1 minute to prepare an adhesive layer (adhesive sheet).

(3) Production of polarizing plate with adhesive layer

A first protective film composed of a thermoplastic resin listed in Table 4 was bonded to one side of a polarizer having a thickness of 23 μm and an iodine-adsorbed polyvinyl alcohol film stretched along one axis via an adhesive, and a second protective film composed of a (meth) acrylic resin was bonded to the other side via an adhesive different from the above-mentioned one, thereby producing a polarizing plate. Then, the outer surface of the first protective film was subjected to a corona treatment at an output of 0.3 kW and a line speed of 10 m/min. Then, the corona treated surface was laminated to the surface (adhesive layer surface) opposite to the separation film of the adhesive layer prepared in (2) above by a lamination machine, and then aged at a temperature of 23°C and a relative humidity of 65% to obtain a polarizing plate with an adhesive layer.

The abbreviations listed in the "Protective Film" column of Table 4 refer to the following thermoplastic resins.

AC: (Meth) acrylic resin (contact angle variation rate according to the above definition: 17.2%)

PE: Polyester resin (Contact angle variation rate according to the above definition: 14.7%)

CE: Cellulose resin (contact angle variation rate based on the above definition: 21.7%)

(4) Evaluation of durability

After peeling off the separator film from the polarizing plate with adhesive layer prepared in (3) above, the adhesive layer surface was attached to both sides of a glass substrate for a liquid crystal unit ("Eagle XG" manufactured by Corning) to form a cross Nicol, and a sample for evaluation was prepared. The following three durability tests were performed using this sample.

[Durability test]

‧Heat resistance test at 80℃ in dry conditions for 1000 hours;

‧1000 hours of moisture and heat resistance test in an environment with a temperature of 60°C and a relative humidity of 90%;

‧Keep it in a dry condition at 70℃ for 30 minutes, then keep it in a dry condition at -40℃ for 30 minutes as one cycle, and repeat this operation 500 times for heat shock (HS) test.

Visually observe the samples after each test and evaluate the durability according to the following evaluation criteria. The results are shown in Table 4.

A: No changes in appearance such as floating, peeling, or bubbling are visible

B: Almost no changes in appearance such as floating, peeling, and bubbling are visible

C: Observed many appearance changes such as floating, peeling, bubbling, etc.

D: Clearly noticeable changes in appearance such as floating, peeling, and bubbling

(5) Evaluation of the adhesion between the protective film and the adhesive layer and the aging period

The polarizing plate with adhesive layer prepared in (3) above was cut into a test piece with a width of 25 mm and a length of 150 mm. Then, after peeling off the separation film from the test piece, it was fixed on an adhesion evaluation jig made by Japan System Group Co., Ltd. and the following peeling test was performed. A test rubber sheet [material: chloroprene rubber, hardness: JIS A hardness 65] was pressed against the surface of the adhesive layer. The rubber sheet was moved back and forth on the test piece 20 times, and the surface of the adhesive layer was rubbed with the rubber sheet. The moving direction of the test rubber sheet was parallel to the width direction of the test piece.

Observe the surface of the adhesive layer side of the test piece after the above peeling test. In any embodiment/comparative example, the adhesive layer is peeled off at one end of the width direction of the test piece after the peeling test, and the adhesive layer remains at the other end. The position of the remaining adhesive layer (the position in the length direction of the test piece) is obtained, and the distance from the above one end to the position is measured as the peeling distance. The results are shown in Table 4.

In any of the embodiments/comparative examples, the adhesive layer was prepared by using the adhesive layer with a 3-day aging period or the adhesive layer with a 7-day aging period, and a peeling test was performed. When the peeling distance at the 7-day aging period was 15 mm or less, the adhesion between the protective film and the adhesive layer was good. When the difference between the peeling distance at the 3-day aging period and the peeling distance at the 7-day aging period was 5 mm or less, it was extremely advantageous in shortening the aging period. Furthermore, in Comparative Example 2, when a ring-shaped polyolefin resin film with a contact angle variation rate of 56.3% was used to replace the (meth)acrylic resin as a protective film, the peeling distances after aging for 3 days and 7 days were 14 mm and 11 mm, respectively, and the durability according to the above-mentioned measurement method was also better.

<Production Examples 8 to 10: Production of (meth) acrylic resin for adhesive layer>

In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer, a monomer mixture having the monomer composition shown in Table 5 (weight % when the total amount of monomers is 100 weight %) and diluted with ethyl acetate was placed, and after replacing the air in the apparatus with nitrogen to make it oxygen-free, the internal temperature was raised to 55°C, and then the entire amount of a solution in which azobisisobutyronitrile (polymerization initiator) was dissolved in ethyl acetate was added. After adding the initiator, the temperature was maintained for 1 hour, and then ethyl acetate was continuously added to the reaction vessel while maintaining the internal temperature at 54 to 56°C until the concentration of the (meth)acrylic resin reached 35 weight %, at which time the addition of ethyl acetate was stopped and the temperature was maintained until 12 hours from the time when the addition of ethyl acetate was started. Finally, ethyl acetate was added to adjust the concentration of the (meth)acrylic resin to 20% by weight to prepare an ethyl acetate solution of the (meth)acrylic resin.

The weight average molecular weight (Mw) and glass transition temperature (Tg) of the obtained (meth) acrylic resin were measured. Mw was measured by converting to standard polystyrene at a temperature of 40°C and a flow rate of 1 mL/min using tetrahydrofuran as the eluent, a sample concentration of 5 mg/mL, and a sample introduction volume of 100 μL in a GPC apparatus with 4 "TSKgel XL" manufactured by Tosoh Corporation and 1 "Shodex GPC KF-802" manufactured by Showa Denko Corporation and sold by Showa Tsusho Corporation as columns. Tg was measured using a differential scanning calorimeter (DSC) "EXSTAR DSC 6000" manufactured by SII Nanotech, in a nitrogen environment, at a temperature range of -80 to 50°C and a heating rate of 10°C/min. The monomer composition (weight %) of the monomer mixture used and the Mw, Mw/Mn and Tg of the obtained (meth)acrylic resin are summarized in Table 5.

The abbreviations in the "Monomer Composition" column of Table 5 refer to the following monomers.

BA: n-butyl acrylate

EHA: 2-ethylhexyl acrylate

MA: Methyl acrylate

AA: Acrylic acid

HEA: 2-Hydroxyethyl acrylate

PEA: 2-phenoxyethyl acrylate

PEA2: 2-(2-phenoxyethoxy)ethyl acrylate

BMAM: N-(Butoxymethyl)acrylamide

<Examples 11 to 26>

(1) Preparation of adhesive composition

Relative to 100 parts by weight of the solid content of the (meth) acrylic resin (A) obtained in the above production example, the crosslinking agent (B), compound (C), ionic compound (D) and silane compound (E) shown in Table 6 are mixed in the amounts (parts by weight) shown in Table 6, and ethyl acetate is added to make the solid content concentration become 14% by weight to prepare a solution of the adhesive composition. The amount of each formulation component shown in Table 6 is the weight percentage of the active ingredient contained therein when the product used contains a solvent, etc.

In Table 6, the detailed contents of each blending ingredient represented by the abbreviation are as follows.

B1: Ethyl acetate solution of trihydroxymethylpropane adduct of cresyl diisocyanate (solid content concentration 75%), "CORONATE L" obtained from Nippon Polyurethane Co., Ltd.,

C1: Sodium acetate: obtained from Wako Junyaku Industries (dissolved in acetic acid to prepare a 3.3 wt% solution and added to the adhesive composition.)

C2-1: "AM-130G" acquired by Shin-Nakamura Chemical Industry Co., Ltd. (the following formula:

Methoxylated polyethylene glycol acrylate shown),

C2-2: "M-130G" obtained from Shin-Nakamura Chemical Industry Co., Ltd. (The following formula:

Methoxylated polyethylene glycol methacrylate as shown),

D1: N-octyl-4-methylpyridinium hexafluorophosphate,

S1: 3-Epoxypropylpropyltrimethoxysilane, "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(2) Preparation of adhesive layer

Each adhesive composition prepared in (1) above was applied to the release-treated surface of a release film ("PLR-382051" obtained from LINTEC, also called a release film) made of a release-treated polyethylene terephthalate film using an applicator so that the thickness after drying became 20 μm, and dried at 100°C for 1 minute to prepare an adhesive layer (adhesive sheet).

(3) Production of polarizing plate with adhesive layer

A first protective film composed of a thermoplastic resin listed in Table 7 is bonded to one side of a polarizer having a thickness of 23 μm and an iodine-adsorbed polyvinyl alcohol film stretched along one axis via an adhesive, and a second protective film composed of a (meth) acrylic resin is bonded to the other side via an adhesive different from the above to produce a polarizing plate. Then, the outer surface of the first protective film is subjected to a corona treatment at an output of 0.3 kW and a line speed of 10 m/min. Then, the surface opposite to the separation film of the adhesive layer prepared in (2) is laminated to the corona treated surface (adhesive layer surface) by a lamination machine, and then aged at a temperature of 23°C and a relative humidity of 65% to obtain a polarizing plate with an adhesive layer.

The abbreviations listed in the "Protective Film" column of Table 7 refer to the following thermoplastic resins.

CO: Cyclic polyolefin resin (contact angle variation rate according to the above definition: 56.3%)

AC: (Meth) acrylic resin (contact angle variation rate according to the above definition: 17.2%)

(4) Evaluation of durability

From the polarizing plate with adhesive layer prepared in (3) above, the separator film was peeled off and the adhesive layer surface was attached to both sides of a glass substrate for liquid crystal unit ("Eagle XG" manufactured by Corning) to form a cross Nicol, and a sample for evaluation was prepared. The following three durability tests were carried out using this sample.

[Durability test]

‧Heat resistance test at 80℃ for 1000 hours;

‧1000 hours of moisture and heat resistance test at 60℃ and 90% relative humidity;

‧Keep it in a dry condition at 70℃ for 30 minutes, then keep it in a dry condition at -40℃ for 30 minutes as one cycle, and repeat this operation 500 times for heat shock (HS) test.

Visually observe the samples after each test and evaluate the durability according to the following evaluation criteria. The results are shown in Table 7.

A: No noticeable changes in appearance such as floating, peeling, or bubbling.

B: Almost no changes in appearance such as floating, peeling, and bubbling are visible

C: Observed many appearance changes such as floating, peeling, bubbling, etc.

D: Clearly noticeable changes in appearance such as floating, peeling, and bubbling

(5) Evaluation of the peeling force of optical components with adhesive layers

The polarizing plate with adhesive layer prepared in (3) above was cut into a test piece with a width of 25 mm and a length of 150 mm. Then, after the separation film was peeled off from the test piece, the adhesive layer was attached to a glass substrate for a liquid crystal cell (trade name "EAGLE XG", obtained from Corning, alkali-free glass plate) by a bonding device ("LAMIPACKER" manufactured by FIJIPLA Co., Ltd.). The obtained test piece attached to the glass substrate (optical component with adhesive layer attached to the glass substrate) was pressurized in an autoclave at a temperature of 50°C and a pressure of 5 kg/ ^cm2 (490.3 kPa) for 20 minutes. Then, the samples were placed in an environment at a temperature of 23°C for 24 hours and in an environment at a temperature of 50°C for 48 hours. The samples after placing were clamped in a tensile testing machine ["AUTOGRAPH AGS-X" manufactured by Shimadzu Corporation] and peeled in a 180-degree direction at a temperature of 23°C, a relative humidity of 55%, and a tensile speed of 300 mm/min. The peel strength measured at this time was evaluated as the peel force. Here, the peel force under the condition of storage at a temperature of 23°C for 24 hours is P23, and the peel force under the condition of storage at a temperature of 50°C for 48 hours is P50. The results are shown in Table 7.

1: Polarizer

2: Surface treatment layer

3: Protective film

10: Polarizing plate

20: Adhesive layer

25: Polarizing plate with adhesive layer

30: Glass Plate

Claims (14)

An adhesive composition comprises: 100 parts by weight of a (meth)acrylic resin (A) containing a constituent unit derived from a (meth)acrylic monomer having a hydroxyl group in an amount of 0.1% by weight to 3.5% by weight and having a glass transition temperature of -25°C or below; 0.3 to 1 part by weight of an aromatic isocyanate crosslinking agent (B); and a compound (C) selected from at least one of an organic acid salt (C-1) and a compound containing an alkoxy group (C-2); The organic acid salt (C-1) comprises a carboxylate anion and a relative cation, wherein the carboxylate anion is selected from a linear saturated alkyl carboxylate ion, a linear unsaturated alkyl carboxylate ion, a carboxylate anion having a heterocyclic structure, a dicarboxylate ion, and a carboxylate ion having an oxyethyl skeleton, the relative cation is a metal ion, and the alkoxyl group-containing compound (C-2) is a (meth)acryloyl group-containing compound represented by the following formula (C-2a),

[In the formula, h represents an integer from 1 to 6, ^Q1 represents a hydrogen atom or a methyl group, and ^Q0 represents a group represented by ^Q01 , ^Q03 or ^Q04 ; ^Q01 :

Q ⁰³ :

Q ⁰⁴ :

wherein, in ^Q01 , ^Q2 represents an alkyl group, an aromatic group or an aralkyl group having 1 to 4 carbon atoms which may be substituted by an alkoxy group having 1 to 3 carbon atoms, L represents a single bond or an alkylene group having 1 to 4 carbon atoms, and i represents an integer from 1 to 50; in ^Q03 , y and z each independently represent an integer from 1 to 40; in ^Q04 , e, f and g each independently represent an integer from 1 to 20;] when the aforementioned organic acid salt (C-1) is contained, its content is 0.0001 to 5 parts by weight relative to 100 parts by weight of the aforementioned (meth)acrylic resin (A); when the aforementioned compound containing an alkoxyene group (C-2) is contained, its content is 0.1 to 5 parts by weight relative to 100 parts by weight of the aforementioned (meth)acrylic resin (A). The adhesive composition as described in Item 1 of the patent application, wherein the content of the constituent unit derived from the (meth) acrylic monomer having a hydroxyl group is 0.5% by weight or more. The adhesive composition described in Item 1 of the patent application further contains an ionic compound (D). The adhesive composition described in Item 1 of the patent application further contains a silane compound (E). The adhesive composition as described in item 1 of the patent application, wherein the adhesive composition is formed into a layer on a film composed of a cyclic polyolefin resin, the layered adhesive composition is laminated on an alkali-free glass plate and stored at a temperature of 23° C. for 24 hours, and the peeling force when peeling off from the alkali-free glass plate is set to P(CO)23, and the peeling force when peeling off from the alkali-free glass plate is set to P(CO)23. The adhesive composition is formed into a layer on the film, the layered adhesive composition is layered on an alkali-free glass plate and stored in an environment at a temperature of 50°C for 48 hours. When the peeling force when peeling from the alkali-free glass plate is set to P(CO)50, the ratio of the P(CO)50 to the P(CO)23 (P(CO)50/P(CO)23) is 3.2 or more. The adhesive composition as described in claim 1, wherein the adhesive composition is formed into a layer on a film composed of a (meth) acrylic resin, the layered adhesive composition is laminated on an alkali-free glass plate and stored at a temperature of 23° C. for 24 hours, and the peeling force when peeling off from the alkali-free glass plate is set to P(AC)23, and the peeling force when peeling off from the alkali-free glass plate is set to P(AC)23. The adhesive composition is formed into a layer on the film, and the layered adhesive composition is deposited on an alkali-free glass plate and stored in an environment at a temperature of 50°C for 48 hours. After that, when the peeling force when peeling from the alkali-free glass plate is set to P(AC)50, the ratio of the P(AC)50 to the P(AC)23 (P(AC)50/P(AC)23) is 3.2 or more. The adhesive composition as described in item 1 of the patent application contains the aforementioned organic acid salt (C-1) and the aforementioned compound containing an alkoxy group (C-2); wherein the content of the aforementioned organic acid salt (C-1) is 0.0001 to 0.1 parts by weight relative to 100 parts by weight of the aforementioned (meth) acrylic resin (A); and the content of the aforementioned compound containing an alkoxy group (C-2) is 0.1 to 5 parts by weight relative to 100 parts by weight of the aforementioned (meth) acrylic resin (A). An adhesive layer comprises an adhesive composition described in any one of items 1 to 7 of the patent application scope. An optical component with an adhesive layer, comprising an optical component and an adhesive layer as described in Item 8 of the patent application scope laminated on the optical component. An optical component with an adhesive layer as described in Item 9 of the patent application, wherein the surface of the optical component with the laminated adhesive layer has a contact angle variation rate of less than 40% when subjected to a corona treatment. An optical component with an adhesive layer as described in Item 10 of the patent application, wherein the optical component includes a polarizer and a protective film laminated on the polarizer; The surface is the surface of the protective film. An optical component with an adhesive layer as described in Item 10 of the patent application, wherein the aforementioned surface is a corona-treated surface. An optical component with an adhesive layer as described in any one of items 9 to 12 of the patent application scope further includes a glass substrate laminated on the aforementioned adhesive layer. An optical component with an adhesive layer, comprising a resin film and an adhesive layer laminated on at least one side of the resin film; the adhesive layer comprises an adhesive composition as described in any one of items 1 to 7 of the patent application; the adhesive layer is laminated on an alkali-free glass plate and stored at a temperature of 23°C for 24 hours. , the peeling force when peeling off the alkali-free glass plate is set to P23, and after the adhesive layer is layered on the alkali-free glass plate and stored at a temperature of 50°C for 48 hours, the peeling force when peeling off the alkali-free glass plate is set to P50, and the ratio of the above P50 to the above P23 (P50/P23) is 3.2 or more.

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