KR20210112283A - Adhesive composition and adhesive film - Google Patents

Abstract

Provided is an adhesive composition that can form an adhesive layer having extremely excellent antistatic performance with a surface resistivity of the adhesive layer of 1.0 × 10^(+9) Ω/square or less while not impairing its durability and an adhesive film using the same. The adhesive composition contains: an acrylic polymer which is a copolymer produced by copolymerizing (A) n-butyl acrylate, (B) at least one type selected from t-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, and methyl acrylate, (C) a copolymerizable vinyl monomer containing a hydroxyl group and/or a carboxyl group, (D) a copolymerizable vinyl monomer containing an aromatic group, and (E) an alkoxy group-containing vinyl monomer or a nitrogen-containing vinyl monomer; (F) an antistatic agent; (G) a crosslinking agent comprising a tri- or higher functional isocyanate compound or a di- or higher functional epoxy compound; and (H) a silane coupling agent having an epoxy group, a mercapto group or an acid anhydride group.

Description

Adhesive composition and adhesive film {ADHESIVE COMPOSITION AND ADHESIVE FILM}

This invention relates to the adhesive composition and adhesive film used for the use which bonds an optical member together.

More specifically, a pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive layer having very excellent antistatic performance of ^{1.0 × 10 +9} Ω/□ or less in which the surface resistivity of the pressure-sensitive adhesive layer cannot be achieved with the prior art, and an adhesive film using the same it's about

Various adhesive films for bonding optical members, such as a polarizing plate and retardation plate, to to-be-adhered bodies, such as a liquid crystal cell, through an adhesive layer are proposed (for example, refer patent documents 1-2).

Patent Document 1 discloses (A) (meth)acrylic acid alkylester-based monomer, hydroxyl group-containing monomer and/or carboxyl group-containing monomer, and an acrylic polymer composed of an isocyanate-based crosslinking agent, and (B) an ionic solid solid at 25°C A pressure-sensitive adhesive composition for a polarizing plate containing According to the pressure-sensitive adhesive composition of the invention described in Patent Document 1, not only has excellent antistatic properties, but also has excellent antifouling properties of the polarizing plate obtained because protrusion of the pressure-sensitive adhesive is reduced when it is used for bonding of members for polarizing plates such as polarizing films. has been However, all the surface resistivity of the adhesive layer obtained with the adhesive composition concerning patent document 1 were ^2.0x10+11 ohm/square or more, and the antistatic performance of the adhesive layer was insufficient.

In addition, in Patent Document 2, as a water-dispersible acrylic pressure-sensitive adhesive composition, (meth)acrylate having an alkyl group having 4 to 8 carbon atoms as a monomer as a main component, and an acrylic polymer obtained by copolymerization of a carboxyl group-containing monomer and a nitrogen-containing vinyl monomer Optical containing A pressure-sensitive adhesive composition for use is disclosed. ADVANTAGE OF THE INVENTION According to the adhesive composition of invention described in patent document 2, the liquid crystal display device and organic matter used for the polarizing film fixing use in the image display apparatus by which the outstanding environmental responsiveness and high functionality are calculated|required, especially small electronic terminals, such as a mobile phone. It is said that it can apply suitably to the polarizing film fixing use in an EL display apparatus etc. However, in patent document 2, description regarding the antistatic performance of an adhesive layer is not described at all, and there is no suggestion at all.

Japanese Patent Laid-Open No. 2009-251281 Japanese Laid-Open Patent Publication No. 2012-201734

By the way, in the pressure-sensitive adhesive layer for bonding a polarizing plate and a liquid crystal panel, when the liquid crystal panel is an in-cell panel to which the function of a touch panel is added, the surface resistivity of the pressure-sensitive adhesive layer is set to a lower value than that of the conventional surface resistivity that is being demanded

For this reason, as for the adhesive layer for the use of bonding a polarizing plate to a liquid crystal panel, ^{it is desired that the surface resistivity of the said adhesive layer shall be 1.0x10 +9} ohm/square or less, In the adhesive layer which concerns on the prior art, this very excellent antistatic Demonstrating the performance was a very difficult task.

Moreover, even when such very excellent antistatic performance can be expressed, it was difficult to maintain the antistatic performance of an adhesive layer, and to maintain durability of an adhesive layer at the same time.

The present invention provides a pressure-sensitive adhesive composition capable of forming an adhesive layer having a surface resistivity of the pressure-sensitive adhesive layer of 1.0×10 ⁺⁹ Ω/□ or less and having very excellent antistatic performance and not impairing durability, and an adhesive film using the same make it a task

In order to solve the difficult subject of achieving both such very excellent antistatic performance and durability at the same time, the present inventors worked hard on this subject. As a result, the number of carbon atoms of the alkyl group of the alkyl (meth) acrylate constituting the acrylic polymer of the pressure-sensitive adhesive composition is limited to a specific range, and an acrylic polymer composed of a copolymer obtained by copolymerizing two or more types of alkyl (meth) acrylates in a specific combination. It became possible to solve this subject by setting it as the adhesive composition which further contained at least 1 or more types selected from an alkoxy group containing vinyl monomer and a nitrogen containing vinyl monomer, and melting|fusing point 25 degreeC or more antistatic agent.

The present inventors contain the acrylic polymer and the ionic compound having a melting point of 25° C. or more and 90° C. or less in a ratio of 10 parts by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the acrylic polymer, compared with the conventional pressure-sensitive adhesive composition. The present invention was completed by discovering that a pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive layer having excellent antistatic performance, no antistatic agent precipitation, no deterioration over time, and excellent durability can be obtained.

The pressure-sensitive adhesive composition according to the present invention contains 10 parts by weight of an ionic compound having a melting point of 25° C. or higher with respect to 100 parts by weight of the acrylic polymer in order to make ^{the surface resistivity of the pressure-sensitive adhesive layer a very good antistatic performance of 1.0 × 10 +9 Ω/□ or less.} It is contained in the above ratio. Thus, in this invention, content of the antistatic agent is remarkably increased compared with content in the conventional adhesive composition so that the very excellent antistatic performance which cannot be achieved in the prior art can be acquired.

For this reason, after the durability test in a high-temperature and high-humidity environment of the pressure-sensitive adhesive layer, the antistatic agent contained in a large amount in the pressure-sensitive adhesive layer precipitates on the surface of the pressure-sensitive adhesive layer, and for the purpose of avoiding deterioration in durability, it is contained in the pressure-sensitive adhesive composition With respect to the acrylic polymer, n-butyl acrylate (BA) is the main component, and while selecting and copolymerizing a monomer having good copolymerizability with BA, the technical idea is to contain a specific silane coupling agent.

In addition, in order to solve the above problems, the present invention provides an acrylic polymer, (F) an antistatic agent, and (G) a pressure-sensitive adhesive composition containing a crosslinking agent, wherein the acrylic polymer is (A) n-butyl acrylate, (B ) at least one selected from the group consisting of t-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, and methyl acrylate, and (C) at least one of a copolymerizable vinyl monomer containing a hydroxyl group and/or a carboxyl group. The weight average molecular weight of the copolymer obtained by copolymerizing at least one species, (D) at least one copolymerizable vinyl monomer containing an aromatic group, and (E) at least one selected from the group consisting of an alkoxy group-containing vinyl monomer and a nitrogen-containing vinyl monomer is 1,000,000 It is an acrylic polymer of 3 million, and (F) as the antistatic agent, an ionic compound having a melting point of 25°C or more and 90°C or less is contained in a ratio of 10 parts by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the acrylic polymer, , the (G) crosslinking agent is made by containing at least one crosslinking agent selected from the group consisting of a trifunctional or more functional isocyanate compound and a bifunctional or more functional epoxy compound, wherein the pressure-sensitive adhesive composition is (H) an epoxy group, a mercapto group, an acid anhydride group is made to further contain a selected at least one silane coupling agent of the monomer-type or oligomer-type containing at least one functional group from, and the surface resistivity of the pressure-sensitive adhesive layer crosslinked with the pressure-sensitive adhesive composition 1.0 × 10 ⁺⁹ Ω / □ or less, wherein After subjecting an adhesive layer to the durability test in the test environment of 85 degreeC x 750 hr, or after using it to the durability test in the test environment of 60 degreeC x 90%RH x 750 hr, the said antistatic agent on the said adhesive layer surface It provides a pressure-sensitive adhesive composition, characterized in that does not precipitate.

The acrylic polymer is 40 to 89 parts by weight of (A) n-butyl acrylate, and (B) t-butyl acrylate, isobutyl acrylate, n-butyl methacrylic with respect to 100 parts by weight of the acrylic polymer. rate and at least one total selected from the group consisting of methyl acrylate in a ratio of 5 to 40 parts by weight, and the ratio (A)/(B) of (A) to (B) is 1.0 to 17.8 it is preferable

When a polarizing plate having a total thickness of 80 µm is bonded to alkali-free glass through a pressure-sensitive adhesive layer having a thickness of 20 µm in which the pressure-sensitive adhesive composition is crosslinked, the adhesive force of the pressure-sensitive adhesive layer to alkali-free glass is 1.0 to 6.0 N/25 mm , a test piece formed by bonding a polarizing plate having a total thickness of 10 cm and a total thickness of 80 μm to an alkali-free glass through a pressure-sensitive adhesive layer having a thickness of 20 μm in which the pressure-sensitive adhesive composition is crosslinked, 85° C. × 750 hr Durability in a test environment It is preferable that there is no foaming and peeling after subjecting it to a test or after subjecting it to the durability test in the test environment of 60 degreeCx90%RHx750hr.

With respect to a total of 100 parts by weight of (A) and (B) and (D), the copolymerizable vinyl monomer containing (C) a hydroxyl group and/or a carboxyl group, a copolymerizable monomer containing a hydroxyl group and a carboxyl group At least one selected from the group consisting of copolymerizable monomers containing Roxyhexyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, N-hydroxy (meth)acrylamide, N-hydroxymethyl (meth)acrylamide , N-hydroxyethyl (meth) at least one selected from the group consisting of acrylamide, the copolymerizable monomer containing the carboxyl group is (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) Acrylate, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxypropylhexahydrophthalic acid, 2-(meth)acryloyloxyethylphthalic acid, 2-(meth)acrylo At least one selected from the group consisting of yloxyethyl succinic acid, 2-(meth)acryloyloxyethyl maleic acid, carboxypolycaplactone mono(meth)acrylate, and 2-(meth)acryloyloxyethyltetrahydrophthalic acid. More than one species is preferred.

At least one selected from the above (E) alkoxy group-containing vinyl monomer and nitrogen-containing vinyl monomer is alkoxyalkyl (meth)acrylate, alkoxypolyalkylene glycol mono(meth)acrylate, N-vinyl-substituted lactams, dialkyl-substituted amino at least one selected from alkyl (meth)acrylamide, dialkyl-substituted aminoalkyl (meth)acrylate, and dialkyl-substituted (meth)acrylamide, the sum of (A), (B) and (D) above It is preferable to contain with respect to 100 weight part at least 1 sort(s) selected from the said (E) alkoxy group containing vinyl monomer and a nitrogen containing vinyl monomer in the ratio of 1-20 weight part.

It is preferable that the said (F) antistatic agent is an ionic compound other than the alkali metal salt whose melting|fusing point is 25 degreeC or more and 90 degrees C or less.

It is preferable that the initial surface resistivity of the said adhesive layer and the surface resistivity after using for the durability test in the test environment of 85 degreeCx750hr all are 1.0x10 ⁺⁹ ohm/square or less.

In addition, the present invention provides a pressure-sensitive adhesive film characterized in that the pressure-sensitive adhesive layer crosslinked with the pressure-sensitive adhesive composition is laminated on one side of the resin film.

In addition, the present invention provides an adhesive film for a polarizing plate in which the adhesive film is used.

Moreover, this invention is used for bonding of a polarizing plate and an in-cell panel, The said adhesive film for polarizing plates characterized by the above-mentioned.

In addition, the present invention provides a pressure-sensitive adhesive film characterized in that the release film / pressure-sensitive adhesive layer / release film is formed on one side of the release film, the pressure-sensitive adhesive layer crosslinked with the pressure-sensitive adhesive composition to a thickness of 1㎛ ~ 25㎛ do.

In addition, the present invention provides an optical film with a pressure-sensitive adhesive layer formed on at least one side of the optical film, characterized in that the pressure-sensitive adhesive layer crosslinked with the pressure-sensitive adhesive composition is laminated, and is composed of a release film/adhesive layer/optical film. do.

In addition, the present invention provides a polarizing plate with a pressure-sensitive adhesive layer, characterized in that, on one side of the polarizing plate, the pressure-sensitive adhesive layer crosslinked with the pressure-sensitive adhesive composition is laminated, and is composed of a release film/adhesive layer/polarizing plate.

In addition, the present invention provides a liquid crystal panel characterized in that the polarizing plate formed with the pressure-sensitive adhesive layer is used.

In addition, the present invention provides an in-cell liquid crystal panel, characterized in that the polarizing plate with the pressure-sensitive adhesive layer is used.

ADVANTAGE OF THE INVENTION According to this invention, the surface resistivity of an adhesive layer has ^{very excellent antistatic performance of 1.0x10+9} ohm/square or less which cannot be achieved in the prior art, and the adhesive composition which can form the adhesive layer which does not impair durability. and an adhesive film using the same.

On the other hand, in this invention, content of the antistatic agent is remarkably increased compared with content in the conventional adhesive composition so that the very excellent antistatic performance which cannot be achieved in the prior art can be acquired. For this reason, in this invention, after the durability test in the high temperature and high humidity environment of an adhesive layer, the antistatic agent contained in a large amount in an adhesive layer precipitates on the adhesive layer surface, For the purpose of avoiding that durability falls, an adhesive composition About the acrylic polymer contained in n-butylacrylate (BA) as a main component, while selecting and copolymerizing the monomer with good copolymerizability with BA, it is made to contain a specific silane coupling agent.

Hereinafter, the present invention will be described according to preferred embodiments.

The pressure-sensitive adhesive composition of the present embodiment is a pressure-sensitive adhesive composition containing an acrylic polymer, (F) an antistatic agent, and (G) a crosslinking agent, wherein the acrylic polymer is (A) n-butyl acrylate and (B) t-butyl acryl rate, isobutyl acrylate, n-butyl methacrylate, at least one selected from the group consisting of methyl acrylate, (C) at least one copolymerizable vinyl monomer containing a hydroxyl group and/or a carboxyl group, (D ) An acrylic polymer having a weight average molecular weight of 1 million to 3 million of a copolymer obtained by copolymerizing at least one of the aromatic group-containing copolymerizable vinyl monomers and (E) at least one selected from the group consisting of an alkoxy group-containing vinyl monomer and a nitrogen-containing vinyl monomer. and, as the (F) antistatic agent, an ionic compound having a melting point of 25° C. or higher is contained in a ratio of 10 parts by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the acrylic polymer, and as the (G) crosslinking agent, It consists of containing at least one crosslinking agent selected from the group consisting of a trifunctional or more functional isocyanate compound and a bifunctional or more functional epoxy compound, wherein the pressure-sensitive adhesive composition is (H) at least one functional group selected from an epoxy group, a mercapto group, and an acid anhydride group. and containing as monomer type, or adding a silane coupling agent, an oligomer type which contains made and the surface resistivity of which the pressure-sensitive adhesive layer cross-linked to the pressure-sensitive adhesive composition is 1.0 × 10 ⁺⁹ Ω / □ or less, the pressure-sensitive adhesive layer 85 ℃ × 750hr The antistatic agent does not precipitate on the surface of the pressure-sensitive adhesive layer after being subjected to a durability test under a test environment of do.

At least one selected from the group consisting of (A) n-butyl acrylate and (B) t-butyl acrylate, isobutyl acrylate, n-butyl methacrylate and methyl acrylate is an alkyl (meth) acrylate It corresponds to the monomer. It is preferable to make the monomer of the alkyl (meth)acrylate which comprises an acrylic polymer into the combination of (A) and (B) specific 2 or more types as for the adhesive composition of this embodiment.

It is preferable that the acrylic polymer of this embodiment contains (A) n-butyl acrylate as a main component, and contains (A) n-butyl acrylate in a ratio of 40 to 89 parts by weight with respect to 100 parts by weight of the acrylic polymer. . Further, the acrylic polymer is (A) an alkyl (meth) acrylate monomer other than n-butyl acrylate, (B) t-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, methyl acrylate It is preferable to contain the sum total of at least 1 or more types selected from the group which consists of 5-40 weight part. Moreover, it is preferable that the ratio (A)/(B) of (A) and (B) is 1.0-17.8 in weight ratio.

(C) the copolymerizable vinyl monomer containing a hydroxyl group and/or a carboxyl group is selected from the group consisting of a copolymerizable monomer containing a hydroxyl group (a hydroxyl group-containing monomer) and a copolymerizable monomer containing a carboxyl group (a carboxyl group-containing monomer) At least 1 type or more is mentioned. That is, either a hydroxyl group-containing monomer or a carboxyl group-containing monomer may be selected and copolymerized, and both a hydroxyl group-containing monomer and a carboxyl group-containing monomer may be copolymerized. It is preferable that (C) is contained in the ratio of 0.1-5 weight part with respect to a total of 100 weight part of (A) and (B) and (D).

As the hydroxyl group-containing monomer, for example, 8-hydroxyoctyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl ( Hydroxyalkyl (meth)acrylates, such as meth)acrylate, N-hydroxy (meth)acrylamide, N-hydroxymethyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, etc. At least 1 type or more of hydroxyl-group containing (meth)acrylamide, etc. are mentioned.

In addition, the hydroxyl group-containing monomer contained in the pressure-sensitive adhesive composition according to the present embodiment contains a carboxyl group-containing monomer that is considered to have an effect on the corrosive properties of the obtained pressure-sensitive adhesive layer to an adherend that is easily corroded, such as the ITO surface of the transparent conductive film. It can be used as a copolymerizable monomer to reduce For this reason, the hydroxyl group-containing monomer can help improve the adhesive force of an adhesive layer, and also reduce corrosion property. It is preferable that it is a ratio of 0.1-5.0 weight part with respect to 100 weight part of acrylic polymers, and, as for the ratio of the hydroxyl-containing monomer made into the adhesive composition of this embodiment, it is more preferable that it is a ratio of 0.1-4.4 weight part, 0.1 A proportion of -3.8 parts by weight is particularly preferred.

Examples of the carboxyl group-containing monomer include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, 2-(meth)acryloyloxyethylhexahydrophthalic acid, 2-(meth)acryl Royloxypropylhexahydrophthalic acid, 2-(meth)acryloyloxyethylphthalic acid, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl maleic acid, carboxypolycaplactone mono At least 1 type or more of (meth)acrylate, 2-(meth)acryloyloxyethyl tetrahydrophthalic acid, etc. are mentioned.

Moreover, the carboxyl group-containing monomer contained in the adhesive composition which concerns on this embodiment can provide the cohesive force required with respect to the adhesive layer obtained. It is preferable that the ratio of the carboxyl group-containing monomer in the pressure-sensitive adhesive composition according to the present embodiment is 0 to 5.0 parts by weight (when not copolymerizing the carboxyl group-containing monomer is acceptable) with respect to 100 parts by weight of the acrylic polymer, and the carboxyl group-containing monomer In the case of copolymerizing , it is more preferably 0.01 to 2.3 parts by weight, particularly preferably 0.01 to 1.2 parts by weight, and most preferably 0.01 to 0.8 parts by weight.

(D) Examples of the copolymerizable vinyl monomer containing an aromatic group include benzyl (meth) acrylate, naphthyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxybutyl (meth) acrylate, 2-(1-naphthyloxy)ethyl (meth)acrylate, 2-(2-naphthyloxy)ethyl (meth)acrylate, 6-(1-naphthyloxy)hexyl (meth)acrylate, 6- At least one of (2-naphthyloxy)hexyl (meth)acrylate, 8-(1-naphthyloxy)octyl (meth)acrylate, 8-(2-naphthyloxy)octyl (meth)acrylate, etc. more can be mentioned. (D) When a (meth)acrylate monomer containing an aromatic group is contained as a copolymerizable vinyl monomer containing an aromatic group, copolymerizable with an alkyl (meth)acrylate monomer comprising a combination of (A) and (B) Since this is excellent, it is preferable.

In order for (D) to be distinguished from (C) and (E), it is preferable that (D) does not contain a hydroxyl group, a carboxyl group, an alkoxy group and nitrogen.

In order to obtain an adhesive layer with a high refractive index, it is preferable to mix|blend at least 1 or more types among the (meth)acrylate monomers containing an aromatic group with the adhesive composition which concerns on this embodiment. By copolymerizing the (meth)acrylate monomer containing these aromatic groups with the acrylic polymer, the refractive index of the pressure-sensitive adhesive layer obtained can be increased and adjusted, and the total light transmittance can be improved by reducing the refractive index difference between optical members and reducing total reflection. In the pressure-sensitive adhesive composition according to the present embodiment, the (meth)acrylate monomer containing an aromatic group is preferably contained in a proportion of 5 to 30 parts by weight, and contained in a proportion of 6 to 28 parts by weight, with respect to 100 parts by weight of the acrylic polymer. More preferably, it is particularly preferable to contain it in a proportion of 6 to 24 parts by weight.

(E) As at least 1 type selected from an alkoxy group containing vinyl monomer and a nitrogen containing vinyl monomer, at least 1 type or more selected from the group which consists of an alkoxy group containing vinyl monomer and a nitrogen containing vinyl monomer is mentioned. That is, either one of the alkoxy group-containing vinyl monomer or the nitrogen-containing vinyl monomer may be selected and copolymerized, or both the alkoxy group-containing vinyl monomer and the nitrogen-containing vinyl monomer may be copolymerized. It is preferable that (E) is contained in the ratio of 1-20 weight part with respect to a total of 100 weight part of (A), (B), and (D), It is more preferable that it contains in the ratio of 1-18 weight part. and it is particularly preferably contained in a ratio of 2 to 16 parts by weight.

In order for (E) to be distinguished from (C), it is preferable that (E) does not contain a hydroxyl group and a carboxyl group. Moreover, in order for (E) to be distinguished from (D), it is preferable that (E) does not contain an aromatic group. The alkoxy group-containing vinyl monomer does not need to contain nitrogen, and the nitrogen-containing vinyl monomer does not need to contain an alkoxy group. (E) may be, for example, a vinyl monomer containing an alkoxy group and nitrogen, such as alkoxyalkyl (meth)acrylamide.

Examples of the alkoxy group-containing vinyl monomer include at least one selected from alkoxyalkyl (meth)acrylate and alkoxypolyalkylene glycol mono(meth)acrylate.

Specific examples of the alkoxyalkyl acrylate include 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-propoxyethyl (meth)acrylate, 2-isopropoxyethyl ( meth) acrylate, 2-butoxyethyl (meth) acrylate, 2-methoxypropyl (meth) acrylate, 2-ethoxypropyl (meth) acrylate, 2-propoxypropyl (meth) acrylate, 2 -Isopropoxypropyl (meth) acrylate, 2-butoxypropyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 3-propoxypropyl ( meth) acrylate, 3-isopropoxypropyl (meth) acrylate, 3-butoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 4-ethoxybutyl (meth) acrylate, 4-propoxybutyl (meth)acrylate, 4-isopropoxybutyl (meth)acrylate, 4-butoxybutyl (meth)acrylate, etc. are mentioned.

Specific examples of the alkoxy polyalkylene glycol mono (meth) acrylate include methoxy polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol (meth) acrylate, methoxy polypropylene glycol (meth) acrylate, ethoxy Polypropylene glycol (meth)acrylate, methoxy polybutylene glycol (meth)acrylate, ethoxy polybutylene glycol (meth)acrylate, etc. are mentioned. On the other hand, the alkoxy polyalkylene glycol mono(meth)acrylate is a monomer in which the hydroxyl group at one end of polyalkylene glycol is an alkyl ether and the hydroxyl group at the other end of the polyalkylene glycol is (meth)acrylate.

As the nitrogen-containing vinyl monomer, at least one selected from N-vinyl-substituted lactams, dialkyl-substituted aminoalkyl (meth)acrylamide, dialkyl-substituted aminoalkyl (meth)acrylate, and dialkyl-substituted (meth)acrylamide; can be heard

Examples of the N-vinyl-substituted lactams include N-vinyl-2-pyrrolidone, N-vinylcaprolactam, and N-vinyl-2-piperidone.

Examples of dialkyl-substituted aminoalkyl (meth)acrylamide include dimethylaminoethyl (meth)acrylamide, diethylaminoethyl (meth)acrylamide, dimethylaminopropyl (meth)acrylamide, diethylaminopropyl (meth)acrylamide, Dipropylaminopropyl (meth)acrylamide, diisopropylaminopropyl (meth)acrylamide, ethylmethylaminopropyl (meth)acrylamide, methylpropylaminopropyl (meth)acrylamide, methylisopropylaminopropyl (meth)acrylamide amide etc. are mentioned.

Examples of the dialkyl-substituted aminoalkyl (meth)acrylate include dimethylaminomethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, dimethylaminoisopropyl (meth)acrylate, and dimethyl Aminobutyl (meth)acrylate, diethylaminomethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, ethylmethylaminoethyl (meth)acrylate, methylpropylaminoethyl (meth)acrylate, methyliso Propylaminoethyl (meth)acrylate, dibutylaminoethyl (meth)acrylate, t-butylaminoethyl (meth)acrylate, etc. are mentioned.

Examples of dialkyl-substituted (meth)acrylamide include dimethyl (meth)acrylamide, diethyl (meth)acrylamide, dipropylacrylamide, diisopropyl (meth)acrylamide, dibutyl (meth)acrylamide, ethylmethyl ( Meth)acrylamide, methylpropyl (meth)acrylamide, methyl isopropyl (meth)acrylamide, etc. are mentioned.

The manufacturing method of the acrylic polymer contained in the adhesive composition which concerns on this embodiment is not specifically limited, Well-known polymerization methods, such as a solution polymerization method and an emulsion polymerization method, can be used suitably. It is preferable that the weight average molecular weights of the copolymer of an acrylic polymer are 1 million-3 million.

The pressure-sensitive adhesive composition according to the present embodiment contains (F) an antistatic agent to obtain antistatic performance. (F) It is preferable to contain an ionic compound having a melting point of 25°C or more and 90°C or less as an antistatic agent in a proportion of 10 parts by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the acrylic polymer, in a ratio of 16 to 40 parts by weight. It is more preferable to contain, and it is especially preferable to contain in the ratio of 16-38 weight part. This antistatic agent is an ionic compound which consists of an anion and a cation. The ionic compound is an ionic compound having a melting point of 25°C or higher, and is preferably a solid at room temperature (eg, 25°C). Further, the ionic compound is more preferably an ionic compound having a melting point of 25°C to 90°C, which is solid at a temperature of 25°C, and particularly preferably an ionic compound having a melting point of 25°C to 50°C.

(F) An inorganic or organic anion is mentioned as an anion contained in antistatic agent. Examples of the inorganic anions include PF ₆ ^- , AsF ₆ ^- , SbF ₆ ^- , BF ₄ ^- , AlF ₄ ^- , (FSO ₂ ) ₂ N ^- , FSO ₃ ^- , SCN ^- , ClO ₄ ^- and the like. Organic anions include sulfonate anion (RSO ₃ ^- ), carboxylate anion (RCOO ^- ), alkoxide or phenoxide anion (RO ^- ), organic imide anion (R ₂ N ^- ), methide (R ₃ C ^- ) anion, an organic borate (R ₄ B ⁻ ) anion, etc., wherein R is at least 1 and an anion having an organic group is exemplified. Examples of the organic group include at least one of an alkyl group, an alkoxy group, an aromatic group (aryl group, aralkyl group, etc.), an alkylcarbonyl group, an aromatic carbonyl group, an alkylsulfonyl group, and an aromatic sulfonyl group. When the anion has two or more Rs, it may be a cyclic type having a bond between two or more Rs. It is preferable that the organic group R contains a fluorine atom (fluoro group). Among them, pentafluorobenzenesulfonate, hexafluorophosphate, bis(trifluoromethanesulfonyl)imide, bis(fluorosulfonyl)imide, triflate, nonafluorobutanesulfonate, and tetrakispenta It is preferable that it is 1 type selected from the group which consists of fluorophenyl borate and tris (pentafluorobenzenesulfonyl) methide.

(E) Examples of the cation contained in the antistatic agent include a pyridinium cation, an imidazolium cation, a pyrimidinium cation, a pyrazolium cation, a pyrrolidinium cation, an ammonium cation, a phosphonium cation, and a sulfonium cation. A cation having an organic group of 1 to 4 is preferable, and in particular, a quaternary ammonium cation (R ₄ N ⁺ ) having an organic group R at least at the nitrogen atom, an N-substituted pyridinium cation, an N-substituted imidazolium cation, or the like is preferable. do. Examples of R include hydrocarbon groups such as acyclic or cyclic alkyl groups and aromatic groups (aryl groups, aralkyl groups, etc.). When the cation has two or more Rs, it may be a cyclic type having a bond between two or more Rs.

The pressure-sensitive adhesive composition according to the present embodiment further contains (G) at least one crosslinking agent selected from the group consisting of a trifunctional or higher functional isocyanate compound and a bifunctional or higher functional epoxy compound as a crosslinking agent. The ratio of the (G) crosslinking agent contained in the pressure-sensitive adhesive composition according to the present embodiment is preferably 0.01 to 5 parts by weight, more preferably 0.01 to 3 parts by weight, more preferably 0.01 to 100 parts by weight of the acrylic polymer. It is particularly preferred that the proportion is -0.8 parts by weight.

The trifunctional or more functional isocyanate compound includes, for example, a buret-modified product or isocyanurate-modified product of diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate, and xylylene diisocyanate. , trimethylolpropane, and adducts with trivalent or higher polyols, such as glycerin, etc. are mentioned.

The diglycidyl ethers of glycols, diglycidyl ethers of bisphenols, triglycidyl ethers of triols, diglycidyl esters of dicarboxylic acids, and diglycidyl substituted and amines and tetraglycidyl-substituted diamines.

The pressure-sensitive adhesive composition according to the present embodiment further contains (H) a silane coupling agent. (H) As a silane coupling agent, it has at least 1 organic functional group and at least 1 hydrolysable group in 1 molecule, The compound which is the alkoxy group etc. which the said hydrolysable group couple|bonded with the silicon atom is mentioned. (H) The silane coupling agent contains at least one functional group selected from an epoxy group, a mercapto group, and an acid anhydride group. (H) A silane coupling agent can use at least 1 type or more of one or both of a monomer type and an oligomer type. It is preferable that the ratio of the silane coupling agent contained in the adhesive composition which concerns on this embodiment is a ratio of 0.01-0.5 weight part with respect to 100 weight part of acrylic polymers.

Examples of the silane coupling agent having an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxy Propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl) ) Ethylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 5,6-epoxyhexyltrimethoxysilane, 5,6-epoxyhexylmethyldimethoxysilane, 5,6- Epoxy hexyl methyl diethoxy silane, 5, 6- epoxy hexyl triethoxy silane, etc. are mentioned. As a silane coupling agent having a mercapto group, for example, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, 3-mercaptopropyltri Ethoxysilane etc. are mentioned. Examples of the silane coupling agent having an acid anhydride group include 3-trimethoxysilylpropyl succinic anhydride and 3-triethoxysilylpropyl succinic anhydride. Moreover, the oligomerized alkoxy oligomer (silicone alkoxy oligomer) etc. can be used as a silane coupling agent.

The pressure-sensitive adhesive composition of the present embodiment can be appropriately formulated with known additives such as antioxidants, surfactants, curing accelerators, plasticizers, fillers, crosslinking catalysts, crosslinking retarders, curing retarders, processing aids, and antioxidants as optional components. have. These may be used individually or in combination of 2 or more types.

The surface resistivity of the pressure-sensitive adhesive layer crosslinked pressure-sensitive adhesive composition of the present embodiment, 1.0 × 10 ⁺⁹ Ω / □ or less it is preferred, more preferably 9.0 × 10 ⁺⁸ Ω / □ or less, 6.0 × 10 ⁺⁸ Ω / □ or less Especially preferred. In this pressure-sensitive adhesive layer, both the initial surface resistivity and the surface resistivity after the durability test ^{are preferably 1.0×10 +9} Ω/□ or less, more preferably 9.0×10 ⁺⁸ Ω/□ or less, and 6.0×10 ⁺⁸ Ω/□ or less. Especially preferred. Here, initial stage surface resistivity is the surface resistivity before subjecting an adhesive layer to a durability test. In addition, the surface resistivity after a durability test is the surface resistivity after using an adhesive layer for the durability test in the test environment of 85 degreeC x 750 hr. Here, dry conditions may be sufficient as the test environment of 85 degreeC x 750 hr.

The pressure-sensitive adhesive layer in which the pressure-sensitive adhesive composition of the present embodiment is crosslinked is subjected to a durability test under a test environment of 85° C. × 750 hr and a durability test under a test environment of 60° C. × 90%RH × 750 hr, and then applied to the pressure-sensitive adhesive layer surface. (F) The antistatic agent does not precipitate. Here, dry conditions may be sufficient as the test environment of 85 degreeC x 750 hr.

The precipitation prevention performance of the (F) antistatic agent in the adhesive composition of this embodiment produces two or more samples of the adhesive layer which bridge|crosslinked the same adhesive composition, and one sample is in the test environment of 85 degreeC x 750hr. (F) Antistatic agent does not precipitate after being subjected to the durability test of (F) Antistatic agent does not precipitate, and (F) antistatic agent does not precipitate after another sample is subjected to durability test under a test environment of 60°C x 90%RH x 750 hr it may be

When the adhesive layer which bridged|crosslinked the adhesive composition of this embodiment bonds a polarizing plate with a total thickness of 80 micrometers together to alkali-free glass through a 20-micrometer-thick adhesive layer, the adhesive force with respect to the alkali-free glass of an adhesive layer is 1.0-6.0 It is preferable that it is N/25mm.

Moreover, the test piece formed by bonding together a polarizing plate with a total thickness of 10 cm and a total thickness of 80 μm to an alkali-free glass through an adhesive layer having a thickness of 20 μm was subjected to a durability test and 60° C. in a test environment of 85° C. × 750 hr. After subjecting it to the durability test in the test environment of 90%RHx750hr, it is preferable that there is no foaming and peeling.

The performance without foaming and peeling in the pressure-sensitive adhesive composition of this embodiment produced two or more test pieces produced using the same pressure-sensitive adhesive composition, and one test piece was subjected to a durability test under a test environment of 85°C x 750 hr. There may be no foaming and peeling after application, and there may be no foaming and peeling after subjecting another test piece to a durability test in a test environment of 60°C x 90%RH x 750 hr.

After apply|coating the adhesive composition of this embodiment to base materials, such as a resin film and a release film, the adhesive layer which concerns on this embodiment can be obtained by bridge|crosslinking an adhesive composition.

When using the adhesive layer which concerns on this embodiment for bonding between layers of an optical member, etc., in order to reduce reflection of the light ray in the interface of an adhesive layer and an optical member, it is preferable that the difference in refractive index is as small as possible. For this reason, it is preferable that the refractive index of an adhesive layer is 1.47-1.50.

The adhesive film which concerns on this embodiment can be manufactured by forming the adhesive layer which concerns on this embodiment on one side of base materials, such as a resin film and a release film. A resin film, such as a polyester film, etc. can be used as a resin film used as a base material and a release film (separator). The release film may be subjected to a release treatment with a silicone-based or fluorine-based mold release agent or the like on the side surface aligned with the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer. In the resin film serving as the base material, on the opposite side to the side on which the pressure-sensitive adhesive layer of the resin film is formed, antifouling treatment with silicone or fluorine-based release agents or coating agents, silica particles, etc., antistatic treatment by application or mixing of antistatic agents, etc. can As thickness of an adhesive layer, the thickness of 1 micrometer - 25 micrometers is mentioned, for example.

It can also be set as the structure of "release film/adhesive layer/release film" by putting the surface to which the mold release process of the mold release film was given to both surfaces of one adhesive layer, respectively. In this case, bonding with optical members, such as an optical film, becomes possible by peeling the release film of both sides sequentially or simultaneously to expose an adhesion surface. Examples of the optical film include a polarizing film, a retardation film, an antireflection film, an anti-glare (anti-glare) film, an ultraviolet absorbing film, an infrared absorbing film, an optical compensation film, and a brightness improving film. As an apparatus to which an optical member is applied, a liquid crystal panel, an organic electroluminescent panel, a touch panel, an in-cell type liquid crystal panel, etc. are mentioned.

The adhesion film of this embodiment is preferable as an adhesion film for polarizing plates. In particular, you may use for bonding of a polarizing plate and an in-cell panel. Moreover, it can be set as the optical film in which the adhesive layer in which the said adhesive layer is laminated|stacked was formed on at least one surface of the said optical film. By using the adhesive film on one side of the polarizing plate, a polarizing plate with an adhesive layer can be provided. A liquid crystal panel such as an in-cell liquid crystal panel can be provided by using the polarizing plate having the pressure-sensitive adhesive layer formed thereon.

As a specific example of the laminated configuration of the optical film with an adhesive layer formed, "release film / adhesive layer / optical film", "release film / adhesive layer / optical film / adhesive layer / release film", "optical film / adhesive layer / optical Film", "optical film/adhesive layer", "adhesive layer/optical film/adhesive layer", etc. are mentioned. As a specific example of the laminated configuration of the polarizing plate with the pressure-sensitive adhesive layer formed, "Release film/Adhesive layer/Polarizing plate", "Release film/Adhesive layer/Polarizing plate/Adhesive layer/Release film", "Polarizing plate/Adhesive layer", "Adhesive layer/ A polarizing plate/adhesive layer" etc. are mentioned. These laminated structures may be included as partial structures, such as a liquid crystal panel.

Example

Hereinafter, the present invention will be specifically described by way of Examples.

<Production of acrylic polymer>

[Example 1]

Nitrogen gas was introduced into a reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and the air in the reaction apparatus was replaced with nitrogen gas. Thereafter, 70 parts by weight of n-butyl acrylate, 15 parts by weight of n-butyl methacrylate, 2.0 parts by weight of 8-hydroxyoctyl acrylate, 15 parts by weight of benzyl acrylate, and 15 parts by weight of methoxyethyl acrylate were added to the reactor. With the addition, a solvent (ethyl acetate) was added. Then, 0.1 weight part of azobisisobutyronitrile as a polymerization initiator was dripped over 2 hours, it was made to react at 65 degreeC for 6 hours, and the acrylic polymer solution used for Example 1 was obtained.

[Examples 2 to 6 and Comparative Examples 1 to 3]

Acrylic polymer solutions used in Examples 2 to 6 and Comparative Examples 1 to 3 were obtained in the same manner as in Example 1, except that the monomer composition was as described in Table 1 (A) to (E), respectively.

On the other hand, although the measurement result is not shown in particular, the weight average molecular weight of the copolymer contained in the acrylic polymer solution of Examples 1-6 and Comparative Examples 1-3 exists in the range of 1 million-3 million.

<Production of adhesive film>

[Example 1]

With respect to the acrylic polymer solution of Example 1 prepared as described above, 20 parts by weight of tetrabutylammonium triflate salt, 0.1 parts by weight of a crosslinking agent (D-110N), and 0.05 parts by weight of a silane coupling agent (KBM-403) It added in a negative ratio, it stirred and mixed, and the adhesive composition of Example 1 was obtained.

After apply|coating this adhesive composition so that the thickness of the adhesive layer after drying might be set to 20 micrometers on the release film which consists of a silicone resin-coated polyethylene terephthalate (PET) film, the solvent was removed by drying at 90 degreeC. Then, by aging in an atmosphere of 23 ° C. and 50% RH for 7 days, the pressure-sensitive adhesive layer crosslinked with the pressure-sensitive adhesive composition is on one side of the release film, and the pressure-sensitive adhesive of Example 1, which is a release film/adhesive layer/release film got a film.

[Examples 2 to 6 and Comparative Examples 1 to 3]

Except having made the composition of an additive as described in (F)-(H) of Table 1, respectively, it carried out similarly to the adhesive film of the said Example 1, and obtained the adhesive film of Examples 2-6 and Comparative Examples 1-3.

In Table 1, the numerical value listed after the abbreviation of each component represents parts by weight. This weight part was calculated|required by making the sum total of (A), (B), and (D) 100 weight part. In addition, the compound name of the abbreviation of each component used in Table 1 is shown in Table 2. IOAs are included in (B) for convenience. (C) classified the monomer containing a hydroxyl group as "(C)OH" and the monomer containing a carboxyl group as "(C)COOH".

In Table 2, Coronate (registered trademark) L is a trade name of Toso Corporation, D-110N is a trade name of Mitsui Chemicals Corporation, and TETRAD (registered trademark)-X is a trade name of Mitsubishi Gas Chemicals Corporation. In addition, TDI means tolylene diisocyanate, TMP means trimethylolpropane, and XDI means xylylene diisocyanate. In addition, KBM-403, X-12-967C, X-41-1805, and KBM-503 are all brand names of Shin-Etsu Chemical Industry Co., Ltd.|KK.

<Test method and evaluation>

From the adhesive film in Examples 1-6 and Comparative Examples 1-3, the mold release film (silicone resin-coated PET film) was peeled, and one side of the adhesive layer of the said adhesive film was exposed. Then, on one side of a 80-micrometer-thick polarizing plate (resin film), the said adhesive film was bonded through the said adhesive layer, and the adhesive layer which is the structure of a release film / adhesive layer / polarizing plate was obtained.

<Measuring method of adhesive force>

The release film of the polarizing plate with the pressure-sensitive adhesive layer obtained above is peeled off, and on the surface washed with acetone of alkali-free glass (Eagle XG (registered trademark) manufactured by Corning Corporation), through the pressure-sensitive adhesive layer, the polarizing plate with the pressure-sensitive adhesive layer is pressed It bonded together with a roll, and the test piece was created. Then, the said test piece was autoclaved under the conditions of 50 degreeC and 0.5 MPa x 20 minutes. Then, it returned to the atmosphere of 23 degreeC x 50%RH, and the peeling strength of the polarizing plate with an adhesive layer after 1 hour elapsed was measured based on JIS Z0237 "Adhesive tape and adhesive sheet test method" with a tensile tester, 180 The peeling strength at the time of peeling at the speed|rate of 0.3 m/min in ° direction was made into the adhesive force of the adhesive layer with respect to alkali-free glass.

<Measuring method of surface resistivity>

About the polarizing plate with an adhesive layer obtained above, using the resistivity measuring instrument Hirestar (trademark) UP-HT450 (made by Mitsubishi Chemical Analytech), in the atmosphere of 23 degreeC x 50%RH, the surface resistivity of the adhesive layer (Ω) /□) was measured to determine the initial surface resistivity. After doing the durability test in the test environment of 85 degreeC x 750 hr for the same polarizing plate with an adhesive layer, the surface resistivity was measured similarly and the surface resistivity after a durability test was calculated|required.

<Durability test method>

By the method similar to the measurement of adhesive force, the release film of the polarizing plate with an adhesive layer of 10 cm in width was peeled, it bonded together to the surface wash|cleaned with acetone of an alkali free glass, and the test piece was created. Thereafter, the test piece is subjected to a durability test in a test environment of 85°C × 750 hr and a durability test in a test environment of 60°C × 90%RH × 750 hr, and then taken out in an atmosphere of 23°C × 50%RH. , the state of the pressure-sensitive adhesive layer was visually observed after 1 hour to determine durability.

In addition, the judgment criterion of durability was carried out as follows.

○·· There is no foaming or peeling of the pressure-sensitive adhesive layer.

(triangle|delta)... Foaming and peeling have generate|occur|produced in a part of adhesive layer.

x... Foaming and peeling have generate|occur|produced in the whole of the adhesive layer.

<Evaluation method of precipitation state of antistatic agent>

By the method similar to the measurement of adhesive force, the release film of the polarizing plate with an adhesive layer of 10 cm in width was peeled, it bonded together to the surface wash|cleaned with acetone of an alkali free glass, and the test piece was created. Thereafter, the test piece is subjected to a durability test in a test environment of 85°C × 750 hr and a durability test in a test environment of 60°C × 90%RH × 750 hr, and then taken out in an atmosphere of 23°C × 50%RH. , the state of the pressure-sensitive adhesive layer was visually observed after 1 hour to determine the state of precipitation of the antistatic agent on the surface of the pressure-sensitive adhesive layer.

In addition, the judgment criterion of the precipitation state of an antistatic agent was carried out as follows.

○·· There is no precipitation of the antistatic agent on the surface of the pressure-sensitive adhesive layer.

(triangle|delta)... Precipitation of the antistatic agent has generate|occur|produced in a part of the surface of an adhesive layer.

* Precipitation of antistatic agent has generate|occur|produced on the whole surface of x... adhesive layer.

Table 3 shows the evaluation results.

As for the adhesive film of Examples 1-6, the adhesive force with respect to an alkali free glass was 1.0-6.0 N/25 mm. Moreover, the initial stage surface resistivity of an adhesive layer and the surface resistivity after the durability test in the test environment of 85 degreeCx750hr were all 1.0x10 ⁺⁹ ohm/square or less. In addition, there is no foaming and peeling after a durability test under a test environment of 85° C.×750 hr and a durability test under a test environment of 60° C.×90% RH×750 hr, and has durability, and an antistatic agent is added to the surface of the pressure-sensitive adhesive layer. There was no case of precipitation. That is, the evaluation result about the adhesive film of Examples 1-6 demonstrates that the subject of this invention was solvable.

In the adhesive film of Comparative Example 1, the alkyl (meth)acrylate monomer copolymerized with the acrylic polymer is not any of TBA, IBA, BMA, and MA, and (D) a copolymerizable vinyl monomer containing an aromatic group and (E) an alkoxy group At least one selected from the vinyl monomer containing nitrogen and the vinyl monomer containing nitrogen was not copolymerized. For this reason, although the adhesive force of the adhesive layer before a durability test was excessive, the adhesive film of the comparative example 1 was inferior in durability. In addition, since the pressure-sensitive adhesive film of Comparative Example 1 had a higher content ratio of (F) antistatic agent than Comparative Example 3, the surface resistivity of the pressure-sensitive adhesive layer became a low value, but after the durability test, the antistatic agent was completely applied to the surface of the pressure-sensitive adhesive layer. was precipitated

In the adhesive film of Comparative Example 2, at least one selected from (E) an alkoxy group-containing vinyl monomer and a nitrogen-containing vinyl monomer was not copolymerized with the acrylic polymer. And (H) Although a silane coupling agent is contained, it does not contain at least 1 or more types of functional group selected from an epoxy group, a mercapto group, and an acid anhydride group. For this reason, the adhesive film of Comparative Example 2 had poor durability of the adhesive layer, and after the durability test, the antistatic agent partially precipitated on the adhesive layer surface.

In the adhesive film of Comparative Example 3, the alkyl (meth)acrylate monomer copolymerized with the acrylic polymer was neither TBA, IBA, BMA, nor MA, and (D) a copolymerizable vinyl monomer containing an aromatic group was not copolymerized. For this reason, even if the adhesive film of the comparative example 3 did not contain the (H) silane coupling agent, although the adhesive force of the adhesive layer before a durability test was excessive, durability was inferior. Moreover, since the adhesive film of Comparative Example 3 had a small content rate of (F) antistatic agent, although the antistatic agent did not precipitate on the adhesive layer surface after a durability test, the surface resistivity of an adhesive layer became a high value.

Thus, in the adhesive film of Comparative Examples 1-3, the subject of this invention could not be solved.

ADVANTAGE OF THE INVENTION According to this invention, the surface resistivity of an adhesive layer has ^{very excellent antistatic performance of 1.0x10+9} ohm/square or less which cannot be achieved in the prior art, and the adhesive composition which can form the adhesive layer which does not impair durability. and an adhesive film using the same. For this reason, the adhesive film using the adhesive composition which concerns on this invention has a very excellent antistatic performance as an adhesive film for the use of bonding a polarizing plate and a liquid crystal panel, and it has a large industrial utility value from the point of having durability.

Claims (6)

An acrylic polymer, (F) an antistatic agent, and (G) a pressure-sensitive adhesive composition containing a crosslinking agent,
The acrylic polymer is
(A) n-butyl acrylate;
(B) at least one selected from the group consisting of t-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, and methyl acrylate;
(C) at least one of copolymerizable vinyl monomers containing a hydroxyl group and/or a carboxyl group;
(D) at least one of copolymerizable vinyl monomers containing no hydroxyl group, carboxyl group, alkoxy group, and nitrogen and containing an aromatic group;
(E) an acrylic polymer having a weight average molecular weight of 1,000,000 to 3,000,000 of a copolymer obtained by copolymerizing at least one selected from an alkoxy group-containing vinyl monomer and a nitrogen-containing vinyl monomer,
As said (F) antistatic agent, the ionic compound having a melting point of 25 ° C. or more and 90 ° C. or less is contained in a ratio of 10 parts by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the acrylic polymer,
As the (G) crosslinking agent, at least one crosslinking agent selected from the group consisting of a trifunctional or more functional isocyanate compound and a bifunctional or more functional epoxy compound is contained,
The pressure-sensitive adhesive composition comprises (H) an epoxy group, a mercapto group, and a silane coupling agent of a monomer type or an oligomer type containing at least one functional group selected from an acid anhydride group,
The pressure-sensitive adhesive composition, characterized in that the surface resistivity of the pressure-sensitive adhesive layer in which the pressure-sensitive adhesive composition is crosslinked is 1.0×10 ⁺⁹ Ω/□ or less. The method of claim 1,
The acrylic polymer is 40 to 89 parts by weight of (A) n-butyl acrylate, and (B) t-butyl acrylate, isobutyl acrylate, n-butyl methacrylic with respect to 100 parts by weight of the acrylic polymer. rate and at least one total selected from the group consisting of methyl acrylate in a ratio of 5 to 40 parts by weight, and the ratio (A)/(B) of (A) to (B) is 1.0 to 17.8 A pressure-sensitive adhesive composition, characterized in that. An adhesive film in which an adhesive layer obtained by crosslinking the adhesive composition of claim 1 or 2 is laminated on one surface of a resin film. The adhesive film for a polarizing plate using the adhesive film of claim 3 . On one side of the release film, the pressure-sensitive adhesive layer obtained by crosslinking the pressure-sensitive adhesive composition of claim 1 or 2 is formed to a thickness of 1 µm to 25 µm, and the pressure-sensitive adhesive film is composed of a release film/adhesive layer/release film. A liquid crystal panel in which a polarizing plate with an adhesive layer formed by laminating an adhesive layer obtained by crosslinking the adhesive composition of claim 1 or 2 is used on one surface of the polarizing plate.