TWI782896B - Adhesive composition, adhesive layer and optical component having adhesive layer - Google Patents

Abstract

The present invention provides an adhesive composition having excellent endurance when the composition is used as an adhesive layer attached to the surface of an optical component, an adhesive layer having the adhesive composition, and an optical component having the adhesive layer.

The present invention also provides an adhesive composition, an adhesive layer having the adhesive composition, and an optical component having the adhesive layer, wherein the adhesive composition contains: 0.2-4 wt% of a construction unit originated from a (meth)acrylic monomer having a hydroxyl group, 0-4 wt% of a construction unit originated from a (meth)acrylic monomer having a carboxylic group, 100wt/parts of a (meth)acrylic resin (A) having a glass transition temperature of -55℃ or higher, and 0.1-1 wt/parts of an isocyanate base crosslinking agent (B) having an isocyanate group bonded to a carbon atom which constitutes an aliphatic skeleton. This invention further provides an adhesive layer contains above said adhesive composition, and an optical member having such adhesive layer.

Description

Adhesive composition, adhesive layer and optical component with adhesive layer

The present invention relates to an adhesive composition, an adhesive layer containing the adhesive composition, and an optical member provided with the adhesive layer.

The polarizing plate, which is laminated on one side or both sides of the polarizer and bonded with a protective film, is an optical component widely used in image display devices such as liquid crystal display devices or organic electroluminescence (organic EL) display devices, especially in recent years. Widely used in optical components of various portable devices such as mobile phones, smart phones, and tablet terminals. Optical components such as polarizing plates are mostly used by bonding to other components (such as optical components such as liquid crystal cells in liquid crystal display devices) via an adhesive layer [for example, refer to Japanese Patent Laid-Open No. 2010-229321 (Patent Document 1)] . Therefore, for example, a polarizing plate is circulated on the market in the form of a polarizing plate with an adhesive layer provided in advance on one side of the surface in many cases.

[Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2010-229321

Durability is required for an adhesive composition used for an adhesive layer for laminating optical members. That is, the adhesive layer attached to the optical member and assembled in the image display device, etc., is sometimes placed in a high temperature or high temperature and high humidity environment, or placed in an environment where high temperature and low temperature alternately appear. The layer is required to suppress the loss that may be caused by the dimensional change of the adjacent optical member even under these circumstances. This defect is caused by the floating or peeling of the interface between the adhesive layer and the optical member adjacent thereto, and the foaming of the adhesive layer.

However, the conventional adhesive composition sometimes has insufficient durability when attached to an optical member as an adhesive layer. Activation treatment is also difficult to effectively activate the surface, especially the durability is sometimes insufficient.

The object of the present invention is to provide an adhesive composition, an adhesive layer containing the adhesive composition, and an optical member with the adhesive layer provided with the adhesive layer, wherein even if the surface of the optical member is difficult to pass through The surface activated effectively by the surface activation treatment also has good durability when the adhesive composition is attached to the surface as an adhesive layer.

The present invention provides an adhesive composition, an adhesive layer, and an optical member with an adhesive layer shown below.

[1] An adhesive composition comprising: 0.2 to 4% by weight of constituent units derived from a (meth)acrylic monomer having a hydroxyl group, and derived from a (meth)acrylic monomer having a carboxyl group 100 parts by weight of (meth)acrylic resin (A) having a constituent unit content of 0 to 4% by weight and a glass transition temperature of -55°C or higher; and isocyanate groups bonded to the carbon atoms constituting the aliphatic skeleton 0.1 to 1 part by weight of the isocyanate-based crosslinking agent (B).

[2] The adhesive composition according to [1], wherein the isocyanate group is bonded to a carbon atom constituting a methylene group.

[3] The adhesive composition according to [1] or [2], wherein the content of the structural unit derived from the (meth)acrylic monomer having a hydroxyl group is 3.5% by weight or less.

[4] The adhesive composition according to any one of [1] to [3], which further contains an ionic compound (C).

[5] The adhesive composition according to any one of [1] to [4], which further contains a silane compound (D).

[6] An adhesive layer comprising the adhesive composition according to any one of [1] to [5].

[7] An optical member with an adhesive layer, comprising: an optical member, and the adhesive layer according to [6] laminated on the optical member.

[8] The optical member with an adhesive layer according to [7], wherein the surface of the optical member on which the adhesive layer is to be laminated has a contact angle change rate of 40% or less when corona-treated .

[9] The optical member with an adhesive layer according to [8], which is In the present invention, the aforementioned optical member includes a polarizer and a protective film laminated on the polarizer; the aforementioned surface is the surface of the aforementioned protective film.

[10] The optical member with an adhesive layer according to [8] or [9], wherein the surface is a corona-treated surface.

According to the present invention, there can be provided an adhesive composition with good durability, an adhesive layer containing the adhesive composition, and an optical member with an adhesive layer including the adhesive layer.

1‧‧‧Polarizer

2‧‧‧Surface treatment layer

3.4‧‧‧Protective film

7‧‧‧retardation film

8‧‧‧Interlayer adhesive

10‧‧‧polarizer

20‧‧‧adhesive layer

25‧‧‧Polarizing plate with adhesive layer

30‧‧‧Glass substrate

Fig. 1 is a schematic cross-sectional view showing an example of an optical member with an adhesive layer of the present invention.

Fig. 2 is a schematic cross-sectional view showing another example of the optical member with an adhesive layer of the present invention.

Fig. 3 is a schematic cross-sectional view showing another example of the optical member with an adhesive layer of the present invention.

Fig. 4 is a schematic cross-sectional view showing another example of the optical member with an adhesive layer of the present invention.

<Adhesive composition> [1] (meth)acrylic resin (A)

(Meth) acrylic resin (A) contains The polymer of the structural unit of an acrylic monomer is preferably a polymer containing, as a main component, a structural unit derived from a (meth)acrylate represented by the following formula (I) in addition to the structural unit.

In this specification, "(meth)acrylic acid" means acrylic acid and/or methacrylic acid, and "(meth)" when called (meth)acrylate etc. has the same meaning.

In the above formula (I), R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkyl group with 1 to 14 carbons that may be substituted by an alkoxy group with 1 to 10 carbons, or an alkyl group with 1 to 10 carbons that may be substituted by an alkoxy group with 1 to 10 carbons. An aralkyl group having 7 to 21 carbon atoms substituted with an alkoxy group. R ² is preferably an alkyl group having 1 to 14 carbons which may be substituted with an alkoxy group having 1 to 10 carbons.

Specific examples of (meth)acrylate represented by formula (I) include: methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-propyl (meth)acrylate Linear alkyl (meth)acrylates such as butyl, n-octyl (meth)acrylate and lauryl (meth)acrylate; isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate esters, branched alkyl acrylates such as isooctyl (meth)acrylate, etc.

When R ² is an alkyl group substituted by an alkoxy group, that is, when R ² is an alkoxy alkyl group, a specific example of the (meth)acrylate represented by formula (I) includes (meth)acrylic acid 2 - Methoxyethyl ester, ethoxymethyl (meth)acrylate and the like. Specific examples of the (meth)acrylate represented by the formula (I) when R ² is an aralkyl group having 7 to 21 carbon atoms include benzyl (meth)acrylate and the like.

The (meth)acrylate represented by formula (I) may be used alone or in combination of two or more. Among them, the (meth)acrylate preferably contains n-butyl acrylate. The (meth)acrylic resin (A) preferably contains 50% by weight or more of n-butyl acrylate-derived structural units among all structural units constituting it. Of course, other than n-butyl acrylate, the (meth)acrylate represented by formula (I) other than that can also be used together.

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

The (meth)acrylic resin (A) contains a structural unit derived from a (meth)acrylic monomer having a hydroxyl group. Containing such a constituent unit is advantageous in improving the adhesion between the adhesive layer and the optical member and the durability of the adhesive layer. A suitable example of a (meth)acrylic monomer having a hydroxyl group is a (meth)acrylate having a hydroxyl group. Specific examples of (meth)acrylates having hydroxyl groups include: 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, (meth)acrylate base) 2-(2-hydroxyethoxy)ethyl acrylate, 2- or 3-chloro-2-hydroxypropyl (meth)acrylate, diethylene glycol mono(meth)acrylate, etc.

The content of the structural unit derived from the (meth)acrylic monomer having a hydroxyl group is 4% by weight or less, preferably 3.5% by weight or less, in all the structural units constituting the (meth)acrylic resin (A), preferably 3 Weight% or less. When the content of the structural unit derived from the (meth)acrylic monomer having a hydroxyl group exceeds 4% by weight, the durability of the adhesive layer, especially the heat resistance is insufficient. On the other hand, the content of the constituent unit derived from a (meth)acrylic monomer having a hydroxyl group is usually at least 0.2% by weight, preferably at least 0.5% by weight, and particularly preferably at least 1.0% by weight. When the content of the constituent unit derived from the (meth)acrylic monomer having a hydroxyl group is less than 0.2% by weight, the adhesiveness between the adhesive layer and the optical member, the durability of the adhesive layer, and the like are insufficient.

(Meth)acrylic resin (A) may contain the structural unit derived from the monomer which has other polar functional groups other than the (meth)acrylic monomer which has a hydroxyl group. The monomer having a polar functional group is preferably a (meth)acrylic monomer having a polar functional group.

The polar functional group which this monomer has includes a carboxyl group (free carboxyl group), an amine group, a heterocyclic group (such as an epoxy group), and the like.

Specific examples of monomers with other polar functional groups include: monomers with carboxyl groups such as (meth)acrylic acid, methacrylic acid, and β-carboxyethyl (meth)acrylate; acrylmorpholine, vinylhexyl Lactam, N-vinyl-2-pyrrolidone, vinylpyridine, tetrahydrofuryl methyl acrylate, tetrahydrofuryl methyl acrylate modified by caprolactone, 3,4-cyclo(meth)acrylate Oxycyclohexyl methyl ester, glycidyl (meth)acrylate, 2,5-dihydrofuran and other monomers with heterocyclic groups; (meth)aminoethyl acrylate, (meth)acrylic acid N,N - Monomers having an amino group different from that of a heterocycle, such as dimethylaminoethyl ester and dimethylaminopropyl (meth)acrylate, etc. Monomers having other polar functional groups may be used alone or in combination of two or more.

In addition to the (meth)acrylic monomers with hydroxyl groups, the use of monomers with other polar functional groups, especially the use of (meth)acrylic monomers with carboxyl groups, can improve the adhesion between the adhesive layer and the optical member. Adhesiveness and durability (especially heat resistance) of the adhesive layer are advantageous.

The content of the constituent units derived from monomers having other polar functional groups (preferably (meth)acrylic monomers having a carboxyl group) in all constituent units constituting the (meth)acrylic resin (A) is 0% by weight or more, preferably 4% by weight or less. As mentioned above, the (meth)acrylic resin (A) preferably contains a structural unit derived from a (meth)acrylic monomer having a carboxyl group. In the whole constitutional unit, it is preferably at least 0.02% by weight, particularly preferably at least 0.05% by weight, and more preferably at least 0.1% by weight. When the content of the constituent units derived from monomers having other polar functional groups is less than 0.02% by weight, it is difficult to observe the effect of use. On the other hand, the content of constituent units derived from monomers having other polar functional groups (preferably (meth)acrylic monomers having a carboxyl group) is important in the overall composition of the (meth)acrylic resin (A). In the unit, it is preferably at most 4% by weight, particularly preferably at most 3.5% by weight. When the content of the constituent units derived from monomers having other polar functional groups exceeds 4% by weight, the durability, especially the heat resistance, of the adhesive layer tends to be insufficient. Constituent units derived from monomers having polar functional groups including all (meth)acrylic monomers having hydroxyl groups are usually 1 to 10 in all structural units constituting the (meth)acrylic resin (A). % by weight, preferably 1.1 to 8% by weight.

The (meth)acrylic resin (A) may further contain: derived from a monomer having one olefinic double bond and at least one aromatic ring in the molecule (except for the above-mentioned formula (I) or the above-mentioned polar functional The structural unit of the monomer of the base). A suitable example includes a (meth)acrylic monomer having an aromatic ring. Among the (meth)acrylic monomers having aromatic rings, although neopentyl glycol benzoate (meth)acrylates are included, the phenoxy group represented by the following formula (II) is particularly preferred. Ethyl (meth)acrylate:

and other (meth)acrylates with aryloxyalkyl groups.

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 aryl group. When R ⁴ is an alkyl group, its carbon number may be about 1 to 9, when it is an aralkyl group, its carbon number may be about 7 to 11, and when it is an aryl group, its carbon number may be about 6 to 10.

The alkyl group with 1 to ⁹ carbons constituting R in the formula (II) can include methyl, butyl, nonyl, etc., and the aralkyl group with 7 to 11 carbons can include benzyl, benzene, etc. Examples of the ethyl group, naphthylmethyl group, etc., and the aryl group having 6 to 10 carbon atoms include phenyl, tolyl, naphthyl and the like.

Specific examples of (meth)acrylic esters containing phenoxyethyl represented by formula (II) include: 2-phenoxyethyl (meth)acrylate, 2-(2-phenyl (meth)acrylate Oxyethoxy)ethyl ester, (meth)acrylate of nonylphenol modified with ethylene oxide, 2-(o-phenylphenoxy)ethyl (meth)acrylate, etc. (Meth)acrylates containing phenoxyethyl, may be used alone1 species or in combination of two or more species. Among them, (meth)acrylates containing phenoxyethyl preferably include: 2-phenoxyethyl (meth)acrylate, 2-(o-phenylphenoxy)ethyl (meth)acrylate esters and/or 2-(2-phenoxyethoxy)ethyl (meth)acrylate.

Content of the structural unit derived from the monomer which has an aromatic ring is 0 to 20 weight% (for example, 6 to 12 weight%) normally in the whole structural unit which comprises a (meth)acrylic-type resin (A). However, in order to set the glass transition temperature of (meth)acrylic-type resin (A) in the predetermined range mentioned later, it may be preferable not to contain the structural unit derived from the monomer which has an aromatic ring.

The (meth)acrylic resin (A) may also contain monomers other than (meth)acrylic acid esters, monomers with polar functional groups and monomers with aromatic rings ( Hereinafter also referred to as the structural unit of other monomers). Examples of other monomers include: a structural unit derived from (meth)acrylate having an alicyclic structure in the molecule, a structural unit derived from a styrene-based monomer, a structural unit derived from a vinyl-based monomer, A structural unit derived from a monomer having multiple (meth)acrylamide groups in a molecule, a structural unit derived from a (meth)acrylamide compound, etc. Other monomers may be used alone or in combination of two or more.

The alicyclic structure in (meth)acrylates having an alicyclic structure in the molecule refers to a cycloparaffin structure with carbon number usually 5 or more, preferably about 5 to 7. Specific examples of (meth)acrylates having an alicyclic structure include: isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, (meth) Cyclododecyl acrylate, Methylcyclohexyl (meth)acrylate, Trimethylcyclo(meth)acrylate Hexyl ester, tertiary butylcyclohexyl (meth)acrylate, cyclohexylphenyl (meth)acrylate, α-ethoxycyclohexyl acrylate, etc.

Specific examples of styrene-based monomers include: styrene; methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, propyl Alkylstyrenes such as styrene, butylstyrene, hexylstyrene, heptylstyrene, octylstyrene, etc.; halogenated benzenes such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, iodostyrene, etc. Ethylene; nitrostyrene, acetylstyrene, methoxystyrene, divinylbenzene, etc.

Specific examples of vinyl-based monomers include: fatty acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, and vinyl laurate; halogenated vinyl chloride, vinyl bromide, etc. Ethylene; vinylidene halides such as vinylidene chloride; nitrogen-containing aromatic vinyls such as vinylpyridine, vinylpyrrolidone, vinylcarbazole, etc.; butadiene, isoprene, chloroprene, etc. vinyl monomers; acrylonitrile, methacrylonitrile, etc.

Specific examples of monomers having multiple (meth)acryl groups in the molecule include: 1,4-butanediol di(meth)acrylate, 1,6-hexane di(meth)acrylate Diol ester, 1,9-nonanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetra(meth)acrylate Ethylene glycol ester and tripropylene glycol di(meth)acrylate are equal to monomers with 2 (meth)acryl groups in the molecule; trimethylolpropane tri(meth)acrylate is equal to the monomer with 3 ( Meth)acryl monomer, etc.

Specific examples of (meth)acrylamide compounds 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-di Methyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-(3-dimethylaminopropyl) (Meth)acrylamide, N-(1,1-dimethyl-3-oxobutyl)(meth)acrylamide, N-[2-(2-oxo-1-imidazole Pyridyl)ethyl](meth)acrylamide, 2-acrylamino-2-methyl-1-propanesulfonic acid, N-(methoxymethyl)acrylamide, N-(ethyl Oxymethyl)(meth)acrylamide, N-(propoxymethyl)(meth)acrylamide, N-(1-methylethoxymethyl)(meth)acrylamide , N-(1-methylpropoxymethyl)(meth)acrylamide, N-(2-methylpropoxymethyl)(methyl)acrylamide [alias: N-(isobutyl oxymethyl)(meth)acrylamide], N-(butoxymethyl)(meth)acrylamide, N-(1,1-dimethylethoxymethyl)(methyl) ) acrylamide, N-(2-methoxyethyl)(meth)acrylamide, N-(2-ethoxyethyl)(meth)acrylamide, N-(2-propoxy Ethyl)(meth)acrylamide, N-[2-(1-methylethoxy)ethyl](meth)acrylamide, N-[2-(1-methylpropoxy) )ethyl](meth)acrylamide, N-[2-(2-methylpropoxy)ethyl](meth)acrylamide [alias: N-(2-isobutoxyethyl )(meth)acrylamide], N-(2-butoxyethyl)(meth)acrylamide, N-[2-(1,1-dimethylethoxy)ethyl]( Meth)acrylamide, etc. Among them, N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N-(butylene) can be preferably used Oxymethyl)acrylamide, N-(2-methylpropoxymethyl)acrylamide.

(Meth)acrylic resin (A), in the overall structure constituting this In the constituent units, other monomers are usually contained in a ratio of 0 to 20% by weight, preferably 0 to 10% by weight.

The adhesive composition may contain two or more (meth)acrylic resins belonging to the (meth)acrylic resin (A). In addition, the adhesive composition may contain other (meth)acrylic resins different from the (meth)acrylic resin (A). Examples of other (meth)acrylic resins are (meth)acrylic resins having a structural unit derived from a (meth)acrylate ester of formula (I) and not having a polar functional group. However, the adhesive composition preferably contains (meth)acrylic resin (A) as the main component, and the content of (meth)acrylic resin (A) is equal to the total amount of all (meth)acrylic resins. , preferably more than 60% by weight, more preferably more than 80% by weight, more preferably more than 90% by weight.

The (meth)acrylic resin (A) has a glass transition temperature (Tg) measured by a differential scanning calorimeter (DSC) of -55°C or higher, preferably -50°C or higher. According to the adhesive composition of the present invention containing the (meth)acrylic resin (A) having a Tg of -55°C or higher, the adhesion between the adhesive layer and the optical member and the durability of the adhesive layer can be improved, from the point of view of adhesion From the viewpoint of the adhesiveness between the agent layer and the optical member, Tg of the (meth)acrylic resin (A) is usually -20°C or lower, preferably -25°C or lower, particularly preferably -30°C or lower.

The (meth)acrylic resin (A) preferably has a weight average molecular weight (Mw) in terms of standard polystyrene based on gel permeation chromatography (GPC) in the range of 500,000 to 2 million, more preferably in the range of 600,000 to 1.8 million range. When the Mw is more than 500,000, the adhesiveness between the adhesive layer and the optical member in a high-temperature and high-humidity environment is improved, and it is effective in the bond between the adhesive layer and the optical member. There is a tendency to reduce the possibility of floating or peeling between them, and there is a tendency to improve the reworkability of the adhesive layer. In addition, when Mw is 2 million or less, even if the size of the optical member changes when the adhesive layer is bonded to the optical member, the adhesive layer is likely to follow the dimensional change. Therefore, the gap between the adhesive layer and the optical member It is advantageous in terms of adhesion and durability of the adhesive layer. In addition, due to the above followability, when the optical member with the adhesive layer is applied to the liquid crystal display device, the brightness and the brightness of the peripheral part of the liquid crystal cell are eliminated. There is a tendency to suppress blanking or color unevenness due to the difference in brightness at the center. The molecular weight distribution represented by the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is usually about 2-10, preferably 3-8.

The (meth)acrylic resin (A) or 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 manufacture of (meth)acrylic resins, a polymerization initiator is generally used. The polymerization initiator is used at about 0.001 to 5 parts by weight with respect to a total of 100 parts by weight of all the monomers used in the production of the (meth)acrylic resin. In addition, (meth)acrylic resin can also be manufactured using the method of superposing|polymerizing with active energy rays, such as an ultraviolet-ray.

As a polymerization initiator, a thermal polymerization initiator, a photopolymerization initiator, or the like can be used. As a photoinitiator, 4-(2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone etc. are mentioned, for example. Examples of thermal polymerization initiators include: 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclo Hexane-1-carbonitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azo Bis(2,4-dimethyl-4-methoxyvaleronitrile), dimethyl-2,2'-azobis(dimethylpropionate), and 2,2'-azobis( 2-hydroxymethylpropionitrile) and other azo compounds; lauryl peroxide, tertiary butyl hydroperoxide, benzoyl peroxide, tertiary butyl peroxybenzoate, cumene hydroperoxide, peroxide Diisopropyl oxydicarbonate, dipropyl peroxydicarbonate, tertiary butyl peroxyneodecanoate, tertiary butyl peroxypivalate, and peroxide (3,5,5-trimethylhexyl Acyl) and other organic peroxides; potassium persulfate, ammonium persulfate, and hydrogen peroxide and other inorganic peroxides. In addition, a redox system initiator in which a peroxide and a reducing agent are used in combination can also be used as a polymerization initiator.

The method for producing the (meth)acrylic resin is preferably a solution polymerization method among the methods shown above. An example of the solution polymerization method, such as mixing the monomers and organic solvents used, adding a thermal polymerization initiator under a nitrogen atmosphere, and stirring at about 40 to 90°C, preferably at about 50 to 80°C for 3 to 15 hours . In order to control the reaction, a monomer or a thermal polymerization initiator may be added continuously or intermittently during polymerization, or may be added in a state of being dissolved in an organic solvent. Organic solvents such as aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propanol and isopropanol; acetone, methyl ethyl ketone, methyl isobutyl ketone, etc. etc. Ketones etc.

[2] Isocyanate-based crosslinking agent (B)

The adhesive composition further contains an isocyanate-based crosslinking agent (B). This isocyanate crosslinking agent (B) is an isocyanate crosslinking agent which has 2 or more isocyanate groups in a molecule|numerator, and at least 1 isocyanate group is bonded to the carbon atom which comprises an aliphatic skeleton. By using the isocyanate-based crosslinking agent (B) as The crosslinking agent can improve the adhesion between the adhesive layer and the optical member, and the durability of the adhesive layer.

The aforementioned aliphatic skeleton means a skeleton other than an aromatic ring, and includes, for example, an alicyclic structure in addition to a chain or branched hydrocarbon group. The isocyanate-based crosslinking agent (B) may contain an aromatic ring as long as it has an isocyanate group bonded to a carbon atom constituting the aliphatic skeleton.

A suitable example of the isocyanate-based crosslinking agent (B) is an isocyanate-based crosslinking agent in which an isocyanate group is bonded to a carbon atom of a methylene group constituting an aliphatic skeleton.

The number of methylene groups constituting the aliphatic skeleton, that is, the number of carbon atoms constituting the aliphatic skeleton, is usually 1-15, preferably 1-10.

A specific example of the isocyanate-based crosslinking agent (B) is an aliphatic isocyanate-based crosslinking agent composed of an aliphatic skeleton and not containing an aromatic ring. Examples of aliphatic isocyanate-based crosslinking agents include: 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2-methyl-1,5-pentane diisocyanate, 3- Methyl-1,5-pentane diisocyanate, lysine diisocyanate, isophorone diisocyanate, cyclohexyl diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate , Hydrogenated tetramethylxylylene diisocyanate, etc.

Another specific example of the isocyanate-based crosslinking agent (B) is an isocyanate-based crosslinking agent having an isocyanate group bonded to a carbon atom constituting the aliphatic skeleton and containing an aromatic ring. Examples of the isocyanate-based crosslinking agent include xylylene diisocyanate and the like.

Among them, those composed of aliphatic skeleton and not containing aromatic ring The aliphatic isocyanate-based crosslinking agent is beneficial for further improving the adhesion between the adhesive layer and the optical member.

In addition, the isocyanate-based crosslinking agent (B) includes: a polyol compound adduct of the above-mentioned isocyanate compound (for example, an adduct of trimethylolpropane), an isocyanurate compound, and a biuret-type compound, And polyether polyols or polyester polyols, acrylic polyols, polybutadiene polyols, polyisoprene polyols, etc. Derivatives such as isocyanate compounds. The isocyanate crosslinking agent (B) may be used alone or in combination of two or more.

The content of the isocyanate-based crosslinking agent (B) is 0.1 to 1 part by weight, preferably 0.2 to 0.9 parts by weight relative to 100 parts by weight of the (meth)acrylic resin (A). When the content of the isocyanate-based crosslinking agent (B) is less than 0.1 parts by weight, the adhesiveness between the adhesive layer and the optical member may become insufficient depending on the surface material of the optical member on which the adhesive layer is laminated. In addition, depending on the surface material of the optical member on which the adhesive layer is laminated, the durability when the adhesive layer is bonded to the optical member decreases. When content of an isocyanate type crosslinking agent (B) exceeds 1 weight part, even if sufficient aging time is given, the adhesiveness of an adhesive agent layer and an optical member will not be enough. Moreover, durability, especially heat resistance at the time of bonding an adhesive layer to an optical member will fall.

[3] Ionic compound (C)

The adhesive composition may further contain an ionic compound (C) as an antistatic agent for imparting antistatic properties to the adhesive layer. An ionic compound (C) having an inorganic cation or an organic cation, and an inorganic anion or an organic anion Ionic compounds. Two or more types of ionic compounds (C) can be used.

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

Examples of organic cations include imidazolium cations, pyridinium cations, pyrrolidinium cations, ammonium cations, permalium cations, phosphonium cations, and the like.

Among the above cationic components, organic cationic components are preferably used because they have excellent compatibility with the adhesive composition. Among the organic cation components, especially pyridinium cations and imidazolium cations are preferably used from the viewpoint of being less likely to be charged when the peeling film provided on the adhesive layer is peeled off.

Examples of inorganic anions include: chloride anion [Cl ^- ], bromide anion [Br ^- ], iodide anion [I ^- ], tetrachloroaluminate anion [AlCl ₄ ^- ], heptachlorodialuminate 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 ^- ], hexafluorotantalate anion [TaF ₆ ^- ], dicyanoimide anion [(CN) ₂ N ^- ] etc.

Examples of organic anions 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(trifluoromethane Sulfonyl)imide anion [(CF ₃ SO ₂ ) ₂ N ^- ], tris(trifluoromethanesulfonyl)methanide anion [(CF ₃ SO ₂ ) ₃ C ^- ], dimethylphosphinate anion [(CH ₃ ) ₂ POO ^- ], (poly) hydrofluoride 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- ], etc.

Among the above-mentioned anionic components, those containing fluorine atoms are particularly preferably used because they impart an ionic compound (C) excellent in antistatic performance. Specifically, bis(fluorosulfonyl)imide anion, hexafluorophosphate anion, or bis(trifluoromethanesulfonyl)imide anion can be mentioned.

Specific examples of the ionic compound (C) can be appropriately selected from combinations of the aforementioned cationic components and anionic components. When classifying and revealing the example of the ionic compound (C) which has an organic cation according to the structure of an organic cation, what is shown below is mentioned.

Pyridinium salts: N-hexylpyridinium hexafluorophosphate, N-octylpyridinium hexafluorophosphate, N-octyl-4-methylpyridinium hexafluorophosphate, N-butyl-4-methyl Pyridinium 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)imine, N-tetradecyl-4-methylpyridinium bis(fluorosulfonyl)imine, N-hexadecyl-4-methylpyridinium bis(fluorosulfonyl) base) imine, N-benzyl-2-methylpyridinium bis(fluorosulfonyl)imine, N-benzyl-4-methylpyridinium bis(fluorosulfonyl)imine, N -hexylpyridinium bis(trifluoromethanesulfonyl)imide, N-octylpyridinium bis(trifluoromethanesulfonyl)imide, N-octyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide sulfonyl)imine, N-butyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imine.

Imidazolium salt: 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium p-toluenesulfonate, 1-ethyl-3-methylimidazolium bis( Fluorosulfonyl)imine, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imine 1-butyl-3-methylimidazolium mesylate, -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.

Quaternary ammonium salts: tetrabutylammonium hexafluorophosphate, tetrabutylammonium p-toluenesulfonate, (2-hydroxyethyl)trimethylammonium bis(trifluoromethanesulfonyl)imine, (2- Hydroxyethyl)trimethylammonium dimethylphosphinate.

Moreover, when the example of the ionic compound (C) which has an inorganic cation is given, it is as follows.

Lithium bromide, lithium iodide, lithium tetrafluoroborate, lithium hexafluorophosphate, lithium thiocyanate, lithium perchlorate, lithium triflate, lithium bis(fluorosulfonyl)imide , lithium bis(trifluoromethylsulfonyl)imide, lithium bis(pentafluoroethanesulfonyl)imide, lithium tris(trifluoromethylsulfonyl)methanide, lithium p-toluenesulfonate, sodium hexafluoro Phosphate, 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 (C) is preferably solid at room temperature. Compared with the case of using the ionic compound (C) which is liquid at normal temperature, the antistatic performance can be maintained for a long time. From the viewpoint of long-term stability of antistatic properties, the ionic compound (C) preferably has a melting point of 30°C or higher, more preferably 35°C or higher. On the other hand, if the melting point is too high, the compatibility with the (meth)acrylic resin (A) will deteriorate, so the melting point is preferably 90°C or lower, particularly preferably 70°C or lower, more preferably less than 50°C.

Relative to 100 parts by weight of (meth)acrylic resin (A), the content of the ionic compound (C) in the adhesive composition is preferably 0.2 to 8 parts by weight, especially preferably 0.2 to 5 parts by weight, and more preferably 0.3 to 5 parts by weight, particularly preferably 0.5 to 3 parts by weight. When the content of the ionic compound (C) is 0.2 parts by weight or more, it is advantageous for improving the antistatic performance, and when it is 8 parts by weight or less, it is advantageous for maintaining the durability of the adhesive layer.

[4] Silane compound (D)

The adhesive composition may further contain a silane compound (D). Thereby, the adhesion between the adhesive layer and optical components such as glass substrates can be improved.

Silane compounds (D), for example, include: vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxysilane) base) silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-amine Propyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclo Hexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercapto Propyltrimethoxysilane, 3-Glycidoxypropyltrimethoxysilane, 3-Glycidoxypropyltriethoxysilane, 3-Glycidoxypropyldimethoxymethyl silane, 3-glycidoxypropylethoxydimethylsilane, etc. Two or more types of silane compounds can be used.

The silane compound (D) may be in the form of a polysiloxane oligomer. When the polysiloxane oligomer is expressed as a (monomer) oligomer, for example, the following ones are mentioned.

3-Mercaptopropyltrimethoxysilane-Tetramethoxysilane Copolymer, 3-Mercaptopropyltrimethoxysilane-Tetraethoxysilane Copolymer, 3-Mercaptopropyltriethoxysilane-Tetramethoxysilane Mercaptopropyl silane copolymer, 3-mercaptopropyltriethoxysilane-tetraethoxysilane copolymer and other mercaptopropyl-containing copolymers; mercaptomethyltrimethoxysilane-tetramethoxysilane copolymer, mercaptomethyl Trimethoxysilane-tetraethoxysilane copolymer, mercaptomethyltriethoxysilane-tetramethoxysilane copolymer, mercaptomethyltriethoxysilane-tetraethoxysilane copolymer, etc. Methyl copolymers; 3-Glycidoxypropyltrimethoxysilane-Tetramethoxysilane Copolymer, 3-Glycidoxypropyltrimethoxysilane-Tetraethoxysilane Copolymer, 3-Glycidoxypropyltrimethoxysilane Copolymer, 3-Glycidoxypropyltrimethoxysilane Propyltriethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-glycidoxypropyl methyl Dimethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3-glycidoxypropyl methyl Diethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropyl methyldiethoxysilane-tetraethoxysilane copolymer, etc. containing 3-glycidoxypropyl Copolymer of 3-methacryloxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-methacryloxypropyltriethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-Methacryloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer 3-methacryloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropylmethyldiethoxysilane-tetraethoxy Silane copolymers and other copolymers containing methacryloxypropyl; 3-acryloxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3-acryloxypropyltrimethoxysilane -Tetraethoxysilane copolymer, 3-acryloxypropyltriethoxysilane-tetramethoxysilane copolymer, 3-acryloxypropyltriethoxysilane-tetraethoxysilane Copolymer, 3-acryloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-acryloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer , 3-acryloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-acryloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer, etc. Acryloxypropyl copolymer; Vinyltrimethoxysilane-tetramethoxysilane copolymer, vinyltrimethoxysilane-tetraethoxysilane copolymer, vinyltriethoxysilane-tetramethoxysilane copolymer, vinyl triethyl Oxysilane-tetraethoxysilane copolymer, vinylmethyldimethoxysilane-tetramethoxysilane copolymer, vinylmethyldimethoxysilane-tetraethoxysilane copolymer, vinyl Vinyl-containing copolymers such as methyldiethoxysilane-tetramethoxysilane copolymer, vinylmethyldiethoxysilane-tetraethoxysilane copolymer; 3-aminopropyltrimethoxysilane -Tetramethoxysilane copolymer, 3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-aminopropyltriethoxysilane-tetramethoxysilane copolymer, 3-aminopropyl Triethoxysilane-tetraethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetramethoxysilane Ethoxysilane copolymer, 3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer, etc. Amine-based copolymers, etc.

Most of the silane compounds (D) exemplified above are liquid. The content of the silane compound (D) in the adhesive composition is usually 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, more preferably 0.2 parts by weight relative to 100 parts by weight of the (meth)acrylic resin (A). to 0.4 parts by weight. When content of a silane compound (D) is 0.01 weight part or more, the effect of improving the adhesiveness of an adhesive layer and optical members, such as a glass substrate, is easy to be acquired. In addition, content When the content is 10 parts by weight or less, the silane compound (D) can be suppressed from bleeding out from the adhesive layer.

[5] Other ingredients

The adhesive composition may contain a crosslinking catalyst, a weather-resistant stabilizer, a tackifier, a plasticizer, a softener, a dye, a pigment, an inorganic filler, light-scattering particles, and (meth)acrylic resin Additives such as resins other than (A). In addition, it is also useful to formulate an ultraviolet curable compound in the adhesive composition, and after forming the adhesive layer, irradiate it with ultraviolet rays to harden it, thereby forming a harder adhesive layer. Cross-linking catalysts, for example, hexamethylenediamine, ethylenediamine, polyethylenediamine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, Amine compounds such as amines, polyamine resins and melamine resins.

<Adhesive layer>

The adhesive layer of the present invention contains the above-mentioned adhesive composition of the present invention, and is typically composed of the adhesive composition of the present invention. The adhesive layer can be obtained by dissolving or dispersing the components constituting the above-mentioned adhesive composition in a solvent to form a solvent-containing adhesive composition, which is then coated on a base film and dried. The adhesive layer of the present invention is excellent in adhesiveness and durability.

The base film is generally a plastic film, and a typical example thereof includes a release film (separator) subjected to mold release treatment. The release film can be, for example, an adhesive layer to be formed on a film composed of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polyarylate. On the surface, apply a mold release treatment such as polysiloxane treatment. For example, the adhesive composition can be directly coated on the release-treated surface of the release film to form an adhesive layer, and the adhesive layer with the release film can be laminated on the optical member to obtain an optical member with the adhesive layer. In addition, the adhesive composition may be directly coated on the surface of the optical member to form an adhesive layer, and if necessary, a release film may be laminated on the outside of the adhesive layer to form an optical member with the adhesive layer attached. When the adhesive layer is arranged on the surface of the optical member, it is preferable to apply surface activation treatment to the bonding surface of the optical member and/or the bonding surface of the adhesive layer, such as plasma treatment, corona treatment, etc., especially The best is corona treatment.

The thickness of the adhesive layer is preferably 10 to 45 μm, more preferably 10 to 30 μm, more preferably 10 to 20 μm. When the thickness of the adhesive layer exists in this range, it is favorable for the durability of the adhesiveness of an adhesive layer and an optical member, and bonding an adhesive layer to an optical member. For the same reason, the gel fraction of the adhesive layer is preferably in the range of 30 to 85%.

<Optical member with adhesive layer>

The adhesive layer of the present invention can be suitably used as an adhesive layer for bonding members together, especially for bonding optical members together. The optical member with an adhesive layer of the present invention, for example, may not only have an adhesive layer laminated on a certain optical member, but also may have further laminated and bonded other optical members on the outside of the adhesive layer. By.

[1] First Embodiment

A preferred embodiment of the optical member with an adhesive layer of the present invention The state includes: a resin film as an optical member, and an adhesive layer laminated on at least one side thereof. Resin films include: optical films such as polarizers, protective films, retardation films, etc., or the surface used to protect the surface from damage or dirt by bonding to an optical film as a protected body. Protective film (protective film).

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

The protective film can be made of a light-transmitting (preferably optically transparent) resin, such as chain polyolefin resin (polypropylene resin, etc.), cyclic polyolefin resin (norbornene resin, etc.) Polyolefin-based resins such as cellulose triacetate, cellulose diacetate and other cellulose-based resins; polyester-based resins; polycarbonate-based resins; (meth)acrylic resins; polystyrene-based resins; polyetheretherketone Resin; a film made of thermoplastic resin such as polyester resin.

The chain polyolefin-based resin includes, in addition to homopolymers of chain olefins such as polyethylene resins and polypropylene resins, copolymers composed of two or more kinds of chain olefins.

Cyclic polyolefin resin is a general term for resins polymerized with cyclic olefins as polymerization units. Specific examples of cyclic polyolefin resins include ring-opening (co)polymers of cyclic olefins, addition polymers of cyclic olefins, and copolymerization of cyclic olefins with chain olefins such as ethylene and propylene. Compounds (represented by random copolymers), graft polymers modified with unsaturated carboxylic acids or their derivatives, and hydrogenated compounds of these. Comparable among Preferable use: A norbornene-based resin using a norbornene-based monomer such as norbornene or a polycyclic norbornene-based monomer as a cyclic olefin.

The cellulose-based resin is a partially or completely esterified product of cellulose, and examples thereof include acetate, propionate, butyrate, and mixed esters of cellulose. Among them, cellulose triacetate, cellulose diacetate, cellulose acetate propionate, and cellulose acetate butyrate are preferably used.

Polyester-based resins are resins other than the above-mentioned cellulose-based resins having ester bonds, and are generally composed of polycondensates of polyvalent carboxylic acids or their derivatives and polyhydric alcohols. As the polyvalent carboxylic acid or its derivative, dicarboxylic acid or its derivative can be used, and examples thereof include terephthalic acid, isophthalic acid, dimethyl terephthalate, and dimethyl naphthalene dicarboxylate. Diols can be used as the polyhydric alcohol, and examples thereof include ethylene glycol, propanediol, butanediol, neopentyl glycol, and cyclohexanedimethanol.

Specific examples of polyester-based resins include: polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and polyethylene terephthalate Methyl ester, polytrimethylene naphthalate, polycyclohexanedimethyl terephthalate, polycyclohexanedimethylene naphthalate.

Polycarbonate-based resins are composed of polymers in which monomer units are bonded through carbonate groups. The polycarbonate-based resin may be a resin called a modified polycarbonate in which a polymer skeleton is modified, or a copolymerized polycarbonate, or the like.

(Meth)acrylic resins can be polymers with methacrylate as the main monomer, preferably with a small amount of other comonomers sub-copolymerized copolymers. The (meth)acrylic resin is especially preferably a copolymer of methyl methacrylate and methyl acrylate, and the third monofunctional monomer can be further copolymerized.

The third monofunctional monomer, for example, can include: ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethyl methacrylate Methacrylates other than methyl methacrylate such as hexyl methacrylate and 2-hydroxyethyl methacrylate; ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, acrylic acid 2 Acrylic esters such as ethylhexyl ester and 2-hydroxyethyl acrylate; 2-(hydroxymethyl)methyl acrylate, 2-(1-hydroxyethyl)methyl acrylate, 2-(hydroxymethyl)ethyl acrylate Hydroxyalkyl acrylates such as esters and 2-(hydroxymethyl)butyl acrylate; unsaturated acids such as methacrylic acid and acrylic acid; halogenated styrenes such as chlorostyrene and bromostyrene; Substituted styrenes such as phenylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; unsaturated acid anhydrides such as maleic anhydride and methylmaleic anhydride; phenylmaleimide , unsaturated imides such as cyclohexylmaleimide, etc. The third monofunctional monomer may be used alone or in combination of two or more.

Furthermore, a polyfunctional monomer can be copolymerized with (meth)acrylic resin. Polyfunctional monomers, for example, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, di(meth)acrylic acid Tetraethylene glycol ester, nonaethylene glycol di(meth)acrylate and tetradecylene glycol di(meth)acrylate, etc. use acrylic acid or methacrylic acid to convert the hydroxyl groups at both ends of ethylene glycol or its oligomers Esterified; with acrylic acid or Methacrylic acid esterifies the two terminal hydroxyl groups of propylene glycol or its oligomers; neopentyl glycol di(meth)acrylate, hexanediol di(meth)acrylate, butyl di(meth)acrylate Alkanediol esters, etc., which esterify the hydroxyl group of diols with acrylic acid or methacrylic acid; bisphenol A, the alkylene oxide adduct of bisphenol A, or replace these halogens with acrylic acid or methacrylic acid Those who esterify the hydroxyl groups at both ends of the compound; those who use acrylic acid or methacrylic acid to esterify polyols such as trimethylolpropane and neopentyl glycol, and those who use glycidyl acrylate or glycidyl methacrylate The ring-opening addition of the epoxy group to these terminal hydroxyl groups; diprotonic acids such as succinic acid, adipic acid, terephthalic acid, phthalic acid, and their halogen substitutes, and acrylic acid glycidyl Epoxy esters or glycidyl methacrylate ring-opening addition to these alkylene oxide adducts; (meth)aryl acrylate; aromatic divinyl compounds such as divinylbenzene, etc. . Among them, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and neopentyl glycol dimethacrylate are preferably used.

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

The (meth)acrylic resin may contain additives as needed. Additives, such as lubricants, anti-blocking agents, heat stabilizers, antioxidants, antistatic agents, light-resistant agents, impact-resistant modifiers, surfactants Wait.

The (meth)acrylic resin may contain acrylic rubber particles from the viewpoints of film forming properties of the film, impact resistance of the film, and the like. The so-called acrylic rubber particles are particles mainly composed of an elastic polymer mainly composed of acrylate, and examples include those having a single-layer structure substantially composed only of the elastic polymer, or those containing the elastic polymer as a component thereof. 1-layer multi-layer structure. Examples of the elastic polymer include cross-linked elastic copolymers containing alkyl acrylate as the main component, and other vinyl monomers and cross-linkable monomers copolymerizable with the alkyl acrylate. The alkyl acrylate used as the main component of the elastic polymer includes, for example, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc., with an alkyl group having about 1 to 8 carbon atoms, which is particularly preferred. Acrylic acid having an alkyl group having 4 or more carbon atoms can be used. Other vinyl monomers that can be copolymerized with the alkyl acrylate include compounds having one polymerizable carbon-carbon double bond in the molecule, more specifically, methacrylic acid such as methyl methacrylate. Aromatic vinyl compounds such as esters and styrene, vinyl cyanide compounds such as acrylonitrile, etc. The cross-linkable monomers include cross-linkable compounds having at least two polymerizable carbon-carbon double bonds in the molecule, more specifically, ethylene glycol di(meth)acrylate, di(meth)acrylate, (meth)acrylates of polyhydric alcohols such as butanediol meth)acrylate, enyl (meth)acrylic acid esters such as allyl (meth)acrylate, divinylbenzene, and the like.

A laminate of a film made of a (meth)acrylic resin not containing rubber particles and a film made of a (meth)acrylic resin containing rubber particles may also be used as the protective film.

Retardation film is an optical film showing optical anisotropy. In addition to the resins that can be used in the above-mentioned protective films, such as polyvinyl alcohol-based resins, polyarylate-based resins, polyimide-based resins, and polyether-based resins , polyvinylidene fluoride/polymethyl methacrylate resin, liquid crystal polyester resin, ethylene-vinyl acetate copolymer saponified product, polyvinyl chloride resin, etc., can be used to draw the resin film composed of these resins A stretched film obtained by stretching about 1.01 to 6 times. Among them, a stretched film obtained by uniaxially stretching or biaxially stretching a polycarbonate-based resin film, a cycloolefin-based resin film, a (meth)acrylic resin film, or a cellulose-based resin film is preferable. In addition, in this specification, the zero-retardation film is also included in the retardation film (however, it can also be used as a protective film). In addition, films called uniaxial retardation films, wide viewing angle retardation films, and low photoelasticity retardation films can also be applied as retardation films.

The zero retardation film refers to a film whose in-plane retardation value _Re and thickness direction retardation value R _th are both -15 to 15nm. This retardation film can be suitably used in an IPS mode liquid crystal display device. Both the in-plane retardation value _Re and the thickness direction retardation value R _th are preferably -10 to 10 nm, more preferably both are -5 to 5 nm. Here, the in-plane retardation value _Re and the thickness direction retardation value R _th are values at a wavelength of 590 nm.

The in-plane retardation value R _e and the thickness direction retardation value R _th are respectively defined by the following formula: _Re =(n _{x -ny} )×d

R _th =[(n _x +n _y )/2-n _z ]×d

In the formula, n _x is the refractive index in the direction of the slow axis (x-axis direction) in the film plane, and _ny is the refractive index in the direction of the fast axis in the film plane (the y-axis direction perpendicular to the x-axis in the plane), n _z is the refractive index in the film thickness direction (z-axis direction perpendicular to the film surface), and d is the film thickness.

Zero-retardation film, for example, polyolefin-based resins such as cellulose-based resins, chain-like polyolefin-based resins, and cyclic polyolefin-based resins, polyethylene terephthalate-based resins, or (meth)acrylic-based resins can be used. Resin film made of resin. In particular, cellulose-based resins, polyolefin-based resins, or (meth)acrylic resins can be preferably used from the viewpoint of easy control of the retardation value and ease of acquisition. For example, a (meth)acrylic resin may be laminated on one or both sides of a retardation display layer made of a resin different from the (meth)acrylic resin as a retardation film.

In addition, a film expressing optical anisotropy by coating/alignment of a liquid crystal compound, or a film expressing optical anisotropy by coating an inorganic layered compound can also be used as a retardation film. This type of retardation film is known as a temperature-compensating retardation film. In addition, there is a product name "NH Film" by JX Nippon Oil & Energy Co., Ltd. A film with oblique alignment of rod-shaped liquid crystals sold by Fuji Film Co., Ltd., a film of oblique alignment of discotic liquid crystals sold by Fuji Film Co., Ltd. under the trade name of "VAC Film" A fully biaxially aligned film sold under the trade name ", and a biaxially aligned film also sold under the trade name "new VAC Film" by Sumitomo Chemical Co., Ltd.

On the other hand, the surface protection film is a film used for the purpose of protecting the surface of an optical film or the like belonging to a protected body from being damaged or stained, for example, a polarizer belonging to an optical member for a liquid crystal display device, Various optical films such as protective films, retardation films, light-diffusing sheets, and reflective sheets are usually bonded with surface protection on the surface (when there is an adhesive layer on one side, the surface opposite to the adhesive layer) The state of the membrane is fluid. The surface protection film is generally peeled and removed after bonding the above-mentioned optical film to a liquid crystal cell or the like.

The base material of the surface protection film includes, for example: polyolefin-based resins such as polyethylene, polypropylene, and polymethylpentene; fluorinated polyolefin-based resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyfluoroethylene; Resin: Polyester-based resins such as polyethylene naphthalate, polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate/isophthalate copolymer, etc. ; Polyamides such as nylon 6 and nylon 6,6; polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, vinylon (Vinylon) Vinyl polymers such as cellulose triacetate, cellulose diacetate, cellophane and other cellulose resins; polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate and polybutyl acrylate (meth)acrylic resins such as esters; others include polystyrene, polycarbonate, polyarylate, polyimide, etc. The optical member with an adhesive layer of the present invention in which the resin film is a surface protection film is one in which an adhesive layer is provided on the base film.

In the optical member with an adhesive layer according to this embodiment, it is preferable to stick the above-mentioned release film on the surface of the adhesive layer in advance, and to temporarily protect the adhesive until use. In the optical member with an adhesive layer of this embodiment with a release film attached thereto, an adhesive layer can be formed by coating an adhesive composition on a release film, and a resin film can be laminated on the obtained optical member. The method of the adhesive layer; or the method of coating the adhesive composition on the resin film to form the adhesive layer, and attaching the release film to the adhesive surface.

[2] Second Embodiment

Another preferred embodiment of the optical member with an adhesive layer of the present invention is a laminate comprising a resin film and an adhesive layer laminated on at least one surface thereof. The laminate of resin films is preferably a laminate of optical films selected from optical films such as polarizers, protective films, and retardation films. A typical example of a laminate of optical films is a polarizing plate. In the optical member with an adhesive layer according to the present embodiment, it is preferable to stick a release film on the surface of the adhesive layer in advance, and temporarily protect the adhesive until use.

Polarizing plates include: a linear polarizing plate having the property of absorbing linearly polarized light having a vibrating plane incident in a certain direction on the film surface and transmitting linearly polarized light having a vibrating plane perpendicular to the direction; A polarized light separating plate that reflects linearly polarized light on a vibrating surface in a certain direction of the film surface and transmits linearly polarized light on a vibrating surface perpendicular to the direction; and an elliptical polarized light that laminates a retardation film on a linearly polarized plate board etc.

A linear polarizing plate generally has a structure in which the above-mentioned protective film is bonded to one or both sides of the above-mentioned polarizer. When the protective film is pasted on both sides of the polarizer, an adhesive layer can be formed on at least one surface of the protective film. When the protective film is bonded to only one side of the polarizer, an adhesive layer may be formed on the surface of the polarizer (the surface to which the protective film is not bonded). Elliptical polarizers will be The retardation film is laminated on the linear polarizing plate, but the linear polarizing plate generally has the same configuration as above. When laminating the adhesive layer on the elliptically polarizing plate, the adhesive layer is usually laminated on the retardation film side.

A specific example of an optical member with an adhesive layer when the optical member is a polarizing plate will be described with reference to the drawings. In the example shown in FIG. 1 , the protective film 3 having the surface treatment layer 2 is attached to one side of the polarizer 1 with the surface opposite to the surface treatment layer 2 to form the polarizer 10 . An adhesive layer 20 is provided on the surface of the polarizer 1 opposite to the protective film 3 to form a polarizing plate with an adhesive layer (an optical member with an adhesive layer) 25 . The adhesive layer 20 can be attached to the glass substrate 30 through the surface opposite to the polarizing plate 5, and the glass substrate 30 will be described in detail later.

The polarizing plate 25 with an adhesive layer shown in FIG. 2 is the same as that in FIG. 1 except that the polarizing plate 10 includes a second protective film 4 bonded to the other side of the polarizing plate 1 . The adhesive layer 20 is laminated on the outer surface of the second protective film 4 . The polarizing plate 25 with an adhesive layer shown in FIG. 3 is the same as that in FIG. 1 except that the polarizing plate 10 includes a retardation film 7 attached to the other side of the polarizing plate 1 via an interlayer adhesive 8. . The polarizing plate 25 with an adhesive layer shown in FIG. 4 is the same as that shown in FIG. same. In the example shown in FIG. 3 and FIG. 4 , the adhesive layer 20 is attached to the retardation film 7 .

The surface treatment layer 2 formed on the surface of the protective film 3 can be a hard coat layer, an anti-glare layer, an anti-reflection layer, an anti-static layer, and the like. A plurality of layers among these may also be provided. As in the examples shown in Figure 3 and Figure 4, when the partial When the optical plate 10 includes the retardation film 7, a suitable example of the retardation film 7 is a 1/4 wavelength plate in the case of a small-to-medium sized liquid crystal display device. At this time, it is generally arranged so that the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 intersect at almost 45 degrees, but this angle may be slightly deviated from 45 degrees depending on the characteristics of the liquid crystal cell. To a certain degree. On the other hand, in the case of a large liquid crystal display device such as a TV, the retardation film 7 with various retardation values is used for the purpose of retardation compensation or viewing angle compensation of the liquid crystal cell, and in accordance with the characteristics of the liquid crystal cell. At this time, it is generally arranged so that the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 are substantially perpendicular to or substantially parallel to each other. When the retardation film 7 is constituted by a 1/4 wavelength plate, a uniaxial or biaxial stretched film can be suitably used. In addition, when the phase difference film 7 is provided for the purpose of phase difference compensation or viewing angle compensation of the liquid crystal cell, in addition to the uniaxially or biaxially stretched film, it is also possible to use not only the uniaxially or biaxially stretched film but also the thickness direction An aligned film, or a film in which a retardation material such as liquid crystal is coated on a support film and its alignment is fixed, is called an optical compensation film as the retardation film 7 .

The interlayer adhesive 8 in Fig. 3 and Fig. 4 is generally an ordinary (meth)acrylic adhesive, but of course the adhesive layer of the present invention can also be formed. As in the aforementioned large liquid crystal display device, when the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 are arranged in such a manner that they are almost perpendicular or almost parallel, the following can also be used. agent to replace the interlayer adhesive 8. Adhesives include, for example, water-based adhesives that are composed of an aqueous solution or a water dispersion, and that exhibit adhesive force by evaporating water that is a solvent, or that exhibit adhesive force when hardened by ultraviolet irradiation. Focus on UV-curable adhesives, etc. The bonding of the polarizer 1 and the protective films 3 and 4 is usually performed using an adhesive.

In the optical member with an adhesive layer of this embodiment, since the adhesive layer contains the above-mentioned adhesive composition of the present invention, the adhesiveness and durability between the adhesive layer and the optical member are good. According to the present invention, even if the surface of the optical member to which the adhesive layer is to be bonded is a surface that is difficult to be activated by conventional surface activation treatments such as corona treatment or plasma treatment, the bond between the adhesive layer and the optical member can still be obtained. An optical member with an adhesive layer with good adhesion and durability. Here, the surface that is difficult to be activated by surface activation treatment is, for example, a surface that has a contact angle change rate of 40% or less, further 30% or less when corona treatment has been performed. The contact angle change rate is usually at least 0.1%, preferably at least 0.5%.

The contact angle change rate is defined by the following formula: contact angle change rate (%)={(contact angle before corona treatment-contact angle after corona treatment)/contact angle before corona treatment}×100

The so-called contact angle after corona treatment refers to the contact angle after corona treatment is performed once on the above surface under the conditions of output 0.3kW and line speed 10m/min, and then placed in an environment with a temperature of 23°C and a relative humidity of 60% for 24 hours. horn. The contact angle is the contact angle with water, and the unit is "°".

The rate of change of the contact angle after corona treatment described above differs depending on the constituent material of the surface of the optical member. Thermoplastic resins whose rate of change in contact angle is 40% or less include (meth)acrylic resins, cellulose resins, polyester resins, polycarbonate resins, and the like. The surface of the optical member made of such thermoplastic resin can be protective film, The surface of optical films such as phase difference films.

[3] The third embodiment

Another preferred embodiment of the optical member with an adhesive layer of the present invention is to laminate the outer surface of the adhesive layer of the optical member with an adhesive layer in the first or second embodiment above. Other optical components. The other optical member is preferably a glass substrate, and Figs. 1 to 4 collectively show the appearance of bonding the polarizing plate with the adhesive layer in the second embodiment to the glass substrate 30 .

As the glass substrate 30, a glass substrate of a liquid crystal cell, anti-glare glass, glass for sunglasses, etc. are mentioned, for example. As for the material of the glass substrate 30, a soda-lime glass, a low-alkali glass, an alkali-free glass etc. are mentioned, for example. Among them, the glass substrate is preferably a glass substrate of a liquid crystal cell.

A liquid crystal cell usually has a polarizing plate laminated on both sides through an adhesive layer. Among these polarizing plates, only the polarizing plate disposed on the front side (viewing side) of the liquid crystal cell can be the adhesive layer attached in the present invention. or only the polarizing plate disposed on the back side (backlight side) of the liquid crystal cell is the polarizing plate with the adhesive layer of the present invention, or both of them are the adhesive layer of the present invention The polarizer. The driving method of the liquid crystal unit can be any method known in the past. The polarizing plate arranged on the back side (backlight side) usually does not have the surface treatment layer 2 . Various optical films known to be arranged on the back side of the liquid crystal cell, such as a brightness enhancement film, a light-condensing film, and a diffusion film, may also be provided on the outer surface of the polarizing plate arranged outside the back side.

Adhesive-coated polarizers, etc. Adhesive-coated light It can be suitably used in liquid crystal display devices. Liquid crystal display devices, for example, can be suitably used as personal computers including notebook type, desktop type, PDA (Personal Digital Assistant: personal digital assistant), various portable devices such as smart phones and tablet terminals; televisions; Monitors; electronic dictionaries; digital cameras; digital cameras; electronic desktop computers; clocks and other liquid crystal display devices.

[Example]

The following series give examples and comparative examples to illustrate the present invention more specifically, but the present invention is not limited to these examples. In the following examples, the parts and % indicating the usage or content are based on weight unless otherwise stated.

<Production Examples 1 to 9: Production of (meth)acrylic resin for adhesive layer>

Put the monomer composition shown in Table 1 (wt% when the total amount of the monomer is taken as 100wt%) and diluted with ethyl acetate into a cooling tube, a nitrogen inlet tube, a thermometer and a stirrer The reaction vessel was configured to be free of oxygen by replacing the air in the apparatus with nitrogen, and the internal temperature was raised to 55°C. Then, a solution obtained by dissolving azobisisobutyronitrile (polymerization initiator) in ethyl acetate was added in its entirety. Keep the temperature for 1 hour after adding the initiator, then continuously add ethyl acetate into the reaction vessel while keeping the internal temperature at 54 to 56°C, until the concentration of the (meth)acrylic resin becomes 35 Addition of ethyl acetate was stopped at the time point of % by weight, and the temperature was kept at this temperature until 12 hours from the start of addition of ethyl acetate. Finally, ethyl acetate was added to adjust the concentration of the (meth)acrylic resin to 20% by weight to prepare a (meth)acrylic resin. Ethyl acetate solution of fat.

The weight average molecular weight (Mw) and glass transition temperature (Tg) of the obtained (meth)acrylic resin were measured. Mw is obtained by connecting four "TSKgel XL" made by Tosoh Co., Ltd. and one "Shodex GPC KF-802" made by Showa Denko Co., Ltd. and sold by Soko Tsusho Co., Ltd. in series. It is connected as a column and configured in a GPC device. Tetrahydrofuran is used as the eluent, the sample concentration is 5 mg/mL, the sample introduction volume is 100 μL, and the temperature is 40°C, and the flow rate is 1 mL/min. It is measured by standard polystyrene conversion . Tg was measured using a differential scanning calorimeter (DSC) "EXSTAR DSC6000" manufactured by SII Nanotechnology Co., Ltd. under a nitrogen atmosphere at a measurement temperature range of -80 to 50°C and a heating rate of 10°C/min. The monomer composition (% by weight) of the monomer mixture used, and the Mw and Tg of the obtained (meth)acrylic resin are collectively shown in Table 1.

The abbreviations in the column of "monomer composition" in Table 1 mean the following monomers.

BA: butyl acrylate, EHA: 2-ethylhexyl acrylate, MA: methyl acrylate, AA: acrylic acid, HEA: 2-hydroxyethyl acrylate.

<Examples 1 to 10, Comparative Examples 1 to 4> (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 amounts (parts by weight) shown in Table 2 Mix the crosslinking agent (B), ionic compound (C), and silane compound (D) shown in Table 2, and add ethyl acetate so that the solid content concentration becomes 28% by weight to prepare an adhesive composition The solution. The compounding amount of each compounding ingredient shown in Table 2 is the parts by weight of the active ingredients contained in the product used if it contains a solvent, etc.

The details of each compounded component indicated by the abbreviation in Table 2 are as follows.

B1: Ethyl acetate solution of trimethylolpropane adduct of m-xylylene diisocyanate (solid content concentration 75%), "Takenate D-110N" obtained from Mitsui Chemicals Co., Ltd., B2: Six Isocyanurate of methylene diisocyanate, liquid with almost 100% active ingredient, "Coronate HXR" obtained from Nippon Polyurethane Industry Co., Ltd., B3: Trimethylolpropane-added toluene diisocyanate Ethyl acetate solution of the finished product (solid content concentration 75%), "Coronate L" obtained from Nippon Polyurethane Industry Co., Ltd., B4: ethyl acetate solution of isocyanuric acid ester of toluene diisocyanate (solid Ingredient concentration 50%), "Takenate D-204N" obtained from Mitsui Chemicals Co., Ltd., C1: N-butyl-4-methylpyridinium hexafluorophosphate, S1: 3-glycidoxypropyl Trimethoxysilane, "KBM403" obtained from Shin-Etsu Chemical Co., Ltd.

(2) Production of adhesive layer

Using an applicator, apply each adhesive composition prepared in (1) above to a polyethylene terephthalate that has been subjected to mold release treatment so that the thickness after drying becomes 20 μm. The release-treated surface of the release film ["PLR-382051" obtained from Lintec Co., Ltd.] made of the film was dried at 100° C. for 1 minute to produce an adhesive layer (adhesive sheet).

(3) Manufacture of polarizing plate with adhesive layer

Manufactured by attaching a protective film made of the thermoplastic resin described in Table 3 to both sides of a polarizer with a thickness of 23 μm that has been uniaxially stretched with iodine adsorbed and aligned via an adhesive polarizer. Then, with a laminator, the surface (adhesive layer) of the adhesive layer produced in (2) above that is on the opposite side to the separator is attached to the outer surface of the protective film on one side, and then heated at a temperature of 23°C. Aging was carried out for 7 days at a relative humidity of 65%, and a polarizing plate with an adhesive layer was obtained.

The abbreviations written in the column of "Protective Film" in Table 3 refer to the following thermoplastic resins.

AC: (meth)acrylic resin (change rate of contact angle according to the above definition: 17.2%), PE: polyester resin (change rate of contact angle according to the above definition: 14.7%), CE: cellulose resin ( Contact angle change rate according to the above definition: 21.7%).

(4) Evaluation of durability

After peeling off the separator from the polarizing plate with the adhesive layer prepared in (3) above, the adhesive layer was attached to a glass substrate for a liquid crystal cell [manufactured by Corning Co. Eagle XG”] to make evaluation samples. Using this sample, the following three kinds of durability tests were carried out.

[Durability Test]

‧Heat resistance test for 500 hours under dry conditions at a temperature of 80°C, ‧Humidity and heat resistance tests for 500 hours at a temperature of 60°C and a relative humidity of 90%, ‧Keeping for 30 minutes under dry conditions at a temperature of 70°C Then keep the operation under the dry condition at -40°C for 30 minutes as one cycle, and repeat the heat shock (HS) test for 200 cycles.

The samples after each test were visually observed, and durability was evaluated according to the following evaluation criteria. The results are shown in Table 3.

A: No appearance change such as floating, peeling, or foaming was observed at all, B: Almost no appearance change such as floating, peeling, or foaming was observed, C: Many floating, peeling, or foaming were observed Appearance change, D: Appearance change such as floating, peeling, or foaming was remarkably observed.

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

From the polarizing plate with an adhesive layer produced in (3) above, a test piece with a width of 25 mm x a length of 150 mm was cut out. Then, after peeling off the separator sheet from this test piece, it fixed to the adhesive force evaluation jig (jig) made by Nippon System Group Co., Ltd., and implemented the following peeling test. Put the rubber sheet for the test [material: Xinping rubber, hardness: JIS A hardness 65] on the surface of the adhesive layer, and make the rubber sheet go back and forth 20 times on the test piece to rub the surface of the adhesive layer by the rubber sheet . The moving direction of the test rubber sheet is parallel to the width direction of the test piece.

Observe the adhesive layer side of the test piece after the above peel test s surface. In any of the examples and comparative examples, the adhesive layer was peeled off at one end side in the width direction of the test piece after the peeling test, and a part of the adhesive layer remained on the other end side. The position of the remaining adhesive layer (position in the longitudinal direction of the test piece) was obtained, and the distance from the above-mentioned one end to the position was measured as the peeling distance. The results are shown in Table 3. When the peeling distance (7 days during the aging period) is 15 mm or less, it can be considered that the adhesion between the protective film and the adhesive layer is good.

1‧‧‧Polarizer

2‧‧‧Surface treatment layer

3‧‧‧Protective film

10‧‧‧polarizer

20‧‧‧adhesive layer

25‧‧‧Polarizing plate with adhesive layer

30‧‧‧Glass substrate

Claims (9)

An adhesive composition comprising: 0.2 to 2% by weight of a constituent unit derived from a (meth)acrylic monomer having a hydroxyl group; 100 parts by weight of a (meth)acrylic resin (A) with a content of 3 to 4% by weight, an n-butyl (meth)acrylate content of 75% by weight or more, and a glass transition temperature of -55°C or higher; and isocyanate 0.1 to 1 part by weight of an isocyanate-based crosslinking agent (B) whose groups are bonded to carbon atoms constituting the aliphatic skeleton. The adhesive composition described in claim 1, wherein the aforementioned isocyanate group is bonded to a carbon atom constituting a methylene group. The adhesive composition as described in item 1 or 2 of the patent claims further contains an ionic compound (C). The adhesive composition as described in item 1 or 2 of the patent claims further contains a silane compound (D). An adhesive layer containing the adhesive composition described in any one of items 1 to 4 of the patent application. An optical component with an adhesive layer, comprising: an optical component, and the adhesive layer described in claim 5 of the patent application laminated on the optical component. The optical member with an adhesive layer as described in claim 6, wherein the surface of the optical member on which the adhesive layer is to be laminated has a contact angle change rate of 40% or less when corona treatment is performed . The optical component with an adhesive layer as described in claim 7 of the patent application, wherein the aforementioned optical component includes a polarizer and a protective film laminated on the polarizer; the aforementioned surface is the surface of the aforementioned protective film. The optical member with an adhesive layer as described in claim 7 or 8 of the patent claims, wherein the aforementioned surface is a corona-treated surface.

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