JP6969503B2 - Adhesive composition, adhesive polarizing plate and liquid crystal display device - Google Patents

Description

The present invention relates to a pressure-sensitive adhesive composition, a pressure-sensitive polarizing plate and a liquid crystal display device.

Silane coupling agents have two or more different functional groups in the molecule and act as an intermediary for linking organic and inorganic materials that are normally difficult to bond.
One of the functional groups of the silane coupling agent is a hydrolyzable silyl group, which produces a silanol group in the presence of water, and the silanol group reacts with a hydroxyl group on the surface of the inorganic material to chemically interact with the surface of the inorganic material. Form a bond. Further, the other functional group is an organic reaction group such as a vinyl group, an epoxy group, an amino group, a (meth) acrylic group, and a mercapto group that form a chemical bond with an organic material such as various synthetic resins.
Utilizing the characteristics of these reactive groups, they are widely used as modifiers for organic / inorganic resins, adhesive aids, various additives, and the like.

Among the uses of the silane coupling agent, the use as an adhesive modifier of the pressure-sensitive adhesive is typical. For example, the pressure-sensitive adhesive used for attaching a liquid crystal cell and an optical film is a liquid crystal display device (LCD). ) Is becoming larger and wider, and the required adhesive performance is becoming higher.
For example, in the case of LCDs, contrary to the initial expectation that it is difficult to increase the size by 20 inches or more, the size is rapidly increasing. Until now, major manufacturers have focused on producing small panels of 20 inches or less, but in response to recent trends, they are actively introducing the latest technology and expanding the product range to large sizes of 20 inches or more. ..

As described above, in various optical films, the glass used in the manufacture of the liquid crystal display board tends to be increased in size. Under such circumstances, if a defective product occurs at the time of initial pasting, and it becomes necessary to reuse the liquid crystal cell after removing the optical film from the liquid crystal cell and cleaning the liquid crystal cell, the conventional high adhesive strength is applied. Due to the strong adhesive strength of the adhesive, not only is it difficult to re-peel or remove the optical film, but there is also a high possibility of destroying expensive liquid crystal cells, resulting in a significant increase in production costs. It will be.

Therefore, with the increase in size of LCDs, attempts to develop highly functional adhesives that have both adhesiveness, reworkability, and other adhesive performance are continuing.
For example, Patent Document 1 proposes an acrylic pressure-sensitive adhesive composition containing an epoxysilane for the purpose of providing a polarizing plate having excellent durability in a high temperature and high humidity environment.
Not only can the polarizing plate be adhered to the surface of the substrate with good adhesive strength, but the polarizing plate can be peeled off from the surface of the substrate as needed without damaging the substrate or leaving the adhesive remaining. In order to obtain the above, Patent Documents 2 and 3 propose a pressure-sensitive adhesive composition containing an acrylic polymer, a compound having a β-ketoester group and a hydrolyzed silyl group, or a hydrolyzed condensate thereof. In Nos. 4 to 7, pressure-sensitive adhesive compositions containing an acrylic polymer and a compound having a heterocyclic structural group, a urethane or urea linking group, and a hydrolyzed silyl group are proposed.
Further, in Patent Documents 8 to 10, the initial adhesive strength is low and the reworkability is excellent, while the adhesive strength is enhanced under high temperature and high humidity after attachment, and the adhesive has excellent long-term durability as a pressure-sensitive adhesive at the end of the polyether. An acrylic pressure-sensitive adhesive containing an organosilicon compound having an alkoxysilyl group has been proposed.

By using the pressure-sensitive adhesive containing the silane compound as described above, the substrate and the polarizing plate can maintain an appropriate adhesive strength to the extent required in the environment in which they are actually used, but the adhesive strength is heated. It is said that the polarizing plate can be easily peeled off without being excessively high due to such factors and without damaging the liquid crystal element.

However, the performance required for adhesives to support the large-scale tendency of LCDs is not only low initial adhesive strength when attached to glass and excellent reworkability, but also high adhesive strength is exhibited under high temperature and humidity. If it is not necessary, there is a risk that air bubbles, peeling phenomenon, etc. will occur and the durability will be weakened.
In this regard, Patent Document 11 describes an acrylic monomer in the presence of a silane compound in order to provide a pressure-sensitive adhesive composition having a small change in cohesive force and adhesive force with time even under high temperature and humidity and excellent curved adhesive force. A technique of blending a curing agent with an acrylic resin obtained by polymerizing the above has been proposed.
By blending this silane compound, the substrate and the polarizing plate can maintain an appropriate adhesive strength to the extent required in the environment actually used, and the adhesive strength does not become excessively high due to heating or the like. It is described that the polarizing plate can be easily peeled off without damaging the liquid crystal element.

However, it can be said that it is preferable that the adhesive force is high, there are no bubbles or peeling phenomenon, and the durability is excellent, rather than the change in cohesive force and adhesive force with time being small under high temperature and high humidity. That is, it shows an appropriate initial adhesive strength enough to be peeled off at the initial stage of sticking to glass, but it is not necessary to peel off over time, so it should maintain a strengthened and stabilized adhesive strength. Can be said to be necessary.

From this point of view, it cannot be said that the adhesive modifier made of an organosilicon compound described in Patent Documents 2 to 10 has sufficient reworkability, moisture resistance after attachment, adhesive strength, and the like. , There is room for improvement.
From the above, it has been desired to develop a well-balanced pressure-sensitive adhesive that has good initial reworkability and maintains high adhesive strength under high temperature and high humidity.

Japanese Patent No. 3022993 Japanese Patent No. 3533446 Japanese Patent No. 5262672 Japanese Patent No. 4771102 Japanese Patent No. 5365609 Japanese Patent No. 5365610 Japanese Patent Publication No. 2008-506028 Japanese Unexamined Patent Publication No. 2011-219765 Japanese Patent No. 4840888 International Publication No. 2010/26995 Japanese Unexamined Patent Publication No. 8-199144

The present invention has been made in view of the above circumstances, and when it is attached to an object to be adhered such as glass, the initial adhesive force is low and the reworkability is excellent. A pressure-sensitive adhesive composition that increases the adhesive strength with an object to be adhered such as glass and provides a pressure-sensitive adhesive layer having excellent long-term durability, a pressure-sensitive adhesive polarizing plate having a pressure-sensitive adhesive layer formed from this composition, and the pressure-sensitive adhesive polarization. It is an object of the present invention to provide a liquid crystal display device having a plate.

As a result of diligent studies to solve the above problems, the present inventor has found that a composition containing a (meth) acrylic polymer having a predetermined crosslinkable functional group and a blocked isocyanate silane compound in a predetermined ratio has reworkability. The present invention has been completed by finding that the adhesive strength with an adherend such as glass is increased under high temperature or high temperature and high humidity conditions to provide an adhesive layer having excellent long-term durability. bottom.

（式中、Ｒ¹は、それぞれ独立して炭素原子数１〜８のアルキル基を表し、Ｌは、２価の連結基を表し、Ｘは、−Ｏ−または−ＮＲ²−を表し、Ｙは、水素原子または１価の有機基を表し、Ｒ²は、水素原子、炭素原子数１〜８のアルキル基またはＹと結合して環構造を形成することが可能な基を表し、ｍは１〜３の整数を表す。）
３． 前記（Ｂ）ブロック化イソシアネートシラン化合物が、下記式（２）または（３）で表される２の粘着剤組成物、

（式中、Ｒ¹、Ｒ²、Ｙおよびｍは、前記と同じ意味を表し、Ｒ³およびＲ⁴は、それぞれ独立して、水素原子または１価の有機基を表すが、Ｒ³とＲ⁴またはＲ²とＹが互いに連結して環構造を形成していてもよい。）
４． 前記（Ａ）架橋可能な官能基を有する（メタ）アクリル系ポリマーが、（ａ）モノマーと（ｂ）モノマーとの共重合物であり、前記（ａ）モノマーが、（メタ）アクリル酸の非置換炭素原子数１〜１２アルキルエステルモノマーであり、前記（ｂ）モノマーが、水酸基、カルボキシル基、酸無水物基およびアルコキシシリル基から選ばれる１種または２種以上の基を有する、ビニル系モノマー並びに（メタ）アクリル系モノマーの少なくとも一方のモノマーであり、前記（ａ）モノマーと（ｂ）モノマーとの合計１００質量部に占める（ｂ）モノマーの量が０．１〜１０質量部である１〜３のいずれかの粘着剤組成物、
５． 前記（ａ）モノマーが、ブチル（メタ）アクリレート、２−エチルヘキシル（メタ）アクリレート、エチル（メタ）アクリレート、メチル（メタ）アクリレート、ｎ−プロピル（メタ）アクリレート、イソプロピル（メタ）アクリレート、ｔ−ブチル（メタ）アクリレート、ペンチル（メタ）アクリレート、ｎ−オクチル（メタ）アクリレート、イソオクチル（メタ）アクリレート、およびイソノニル（メタ）アクリレートからなる群より選ばれる１種または２種以上のモノマーである４の粘着剤組成物、
６． 前記（ｂ）モノマーが、２−ヒドロキシエチル（メタ）アクリレート、３−ヒドロキシプロピル（メタ）アクリレート、４−ヒドロキシブチル（メタ）アクリレート、ジエチレングリコールモノ（メタ）アクリレート、ジプロピレングリコールモノ（メタ）アクリレート、（メタ）アクリロキシプロピルトリメトキシシラン、（メタ）アクリロキシプロピルトリエトキシシラン、（メタ）アクリロキシプロピルメチルジメトキシシラン、（メタ）アクリロキシプロピルメチルジエトキシシラン、（メタ）アクリロキシメチルトリメトキシシラン、（メタ）アクリロキシメチルトリエトキシシラン、（メタ）アクリロキシメチルメチルジメトキシシラン、（メタ）アクリロキシメチルメチルジエトキシシラン、（メタ）アクリル酸、（メタ）アクリル酸二量体、イタコン酸、マレイン酸、およびマレイン酸無水物からなる群より選ばれる１種または２種以上のモノマーである４または５の粘着剤組成物、
７． （Ｃ）イソシアネート系化合物、エポキシ系化合物、アジリジン系化合物および金属キレート系化合物からなる群より選ばれる１種または２種以上の多官能性架橋剤を、前記（Ａ）成分１００質量部に対して０．０１〜１０質量部含む１〜６のいずれかの粘着剤組成物、
８． 偏光フィルムと、この偏光フィルムの片面または両面に積層された粘着剤層を有し、
前記粘着剤層が、１〜６のいずれかの粘着剤組成物から形成された粘着偏光板、
９． 保護層、反射層、位相差板、光視野角補償フィルムおよび輝度向上フィルムから選ばれる１種以上の機能層を有する８の粘着偏光板、
１０． 一対のガラス基板と、これらの間に封入された液晶とを備える液晶セル、およびこの液晶セルの片面または両面に貼着された、８または９の粘着偏光板とを有する液晶パネルを含む液晶表示装置
を提供する。 That is, the present invention
1. 1. It contains (A) a (meth) acrylic polymer having a crosslinkable functional group and (B) a blocked isocyanate silane compound, and the crosslinkable functional group is a hydroxyl group, a carboxyl group, an acid anhydride group, and an alkoxy. A pressure-sensitive adhesive composition which is one kind or two or more kinds selected from silyl groups and contains 0.001 to 10 parts by mass of the component (B) with respect to 100 parts by mass of the component (A). Stuff,
2. 2. The pressure-sensitive adhesive composition of 1 in which the (B) blocked isocyanate silane compound is represented by the following formula (1).

(In the formula, R ¹ independently represents an alkyl group having 1 to 8 carbon atoms, L represents a divalent linking group, X represents −O− or −NR ²⁻ , and Y. Represents a hydrogen atom or a monovalent organic group, R ² represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a group capable of combining with Y to form a ring structure, and m represents a group. Represents an integer from 1 to 3)
3. 3. The pressure-sensitive adhesive composition of 2 in which the (B) blocked isocyanate silane compound is represented by the following formula (2) or (3).

(In the formula, R ¹ , R ² , Y and m have the same meanings as described above, and R ³ and R ⁴ independently represent a hydrogen atom or a monovalent organic group, but R ³ and R have their respective meanings. ⁴ or R ² and Y may be connected to each other to form a ring structure.)
4. The (A) acrylic polymer having a crosslinkable functional group is a copolymer of (a) a monomer and (b) a monomer, and the (a) monomer is a non- (meth) acrylic acid. A vinyl-based monomer which is an alkyl ester monomer having 1 to 12 substituted carbon atoms, wherein the monomer (b) has one or more groups selected from a hydroxyl group, a carboxyl group, an acid anhydride group and an alkoxysilyl group. In addition, it is at least one of the (meth) acrylic monomers, and the amount of the (b) monomer in 100 parts by mass of the total of the (a) monomer and the (b) monomer is 0.1 to 10 parts by mass 1. The pressure-sensitive adhesive composition according to any one of 3 to 3.
5. The monomer (a) is butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, t-butyl. Adhesion of 4 which is one or more monomers selected from the group consisting of (meth) acrylate, pentyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, and isononyl (meth) acrylate. Agent composition,
6. The monomer (b) is 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, diethylene glycol mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, (Meta) Acryloxypropyltrimethoxysilane, (Meta) Acryloxypropyltriethoxysilane, (Meta) Acryloxypropylmethyldimethoxysilane, (Meta) Acryloxypropylmethyldiethoxysilane, (Meta) Acryloxymethyltrimethoxysilane , (Meta) Acryloxymethyltriethoxysilane, (Meta) Acryloxymethylmethyldimethoxysilane, (Meta) Acryloxymethylmethyldiethoxysilane, (Meta) Acrylic acid, (Meta) Acrylic acid dimer, Itaconic acid, A pressure-sensitive adhesive composition of 4 or 5 which is one or more monomers selected from the group consisting of maleic acid and maleic acid anhydride.
7. (C) One or more polyfunctional cross-linking agents selected from the group consisting of isocyanate compounds, epoxy compounds, aziridine compounds and metal chelate compounds are applied to 100 parts by mass of the component (A). The pressure-sensitive adhesive composition according to any one of 1 to 6 containing 0.01 to 10 parts by mass,
8. It has a polarizing film and an adhesive layer laminated on one or both sides of the polarizing film.
A pressure-sensitive polarizing plate in which the pressure-sensitive adhesive layer is formed from any of the pressure-sensitive adhesive compositions of 1 to 6.
9. Eight adhesive polarizing plates having one or more functional layers selected from a protective layer, a reflective layer, a retardation plate, an optical viewing angle compensating film, and a brightness improving film,
10. A liquid crystal display including a liquid crystal cell having a pair of glass substrates and a liquid crystal encapsulated between them, and a liquid crystal panel having 8 or 9 adhesive polarizing plates attached to one or both sides of the liquid crystal cell. Provide the device.

Since the pressure-sensitive adhesive composition of the present invention is a (meth) acrylic pressure-sensitive adhesive composition containing a blocked isocyanate silane compound as an adhesive modifier component, the initial adhesive strength is low when the pressure-sensitive adhesive composition is attached to glass or the like. It has excellent reworkability, exhibits high adhesive strength by moist heat treatment under high temperature or high temperature and high humidity after pasting, and has excellent long-term durability of the adhesive strength.
That is, by using a silane coupling agent having a blocked isocyanate group, the proportion of the organic part is increased as compared with the silane coupling agent used in the existing technology, and as a result, the compatibility with the resin is improved. As a result, the binding force and interaction with the matrix resin having a hydroxyl group are enhanced, and the adhesiveness between the pressure-sensitive adhesive containing the matrix resin and the substrate is improved. Further, since the silane coupling agent having a blocked isocyanate group has low hydrolyzability of the silyl group, the initial reworkability can be dramatically improved.

Hereinafter, the present invention will be specifically described. In the present invention, the "silane coupling agent" is included in the "organosilicon compound".
The pressure-sensitive adhesive composition according to the present invention contains (A) a (meth) acrylic polymer having a crosslinkable functional group and (B) a blocked isocyanate silane compound.

(A) Acrylic polymer having a crosslinkable functional group The acrylic polymer having a crosslinkable functional group of the component (A) is one selected from a hydroxyl group, a carboxyl group, an acid anhydride group, and an alkoxysilyl group. The present invention is not particularly limited as long as it is an acrylic polymer having two or more cross-linkable functional groups, preferably a hydroxyl group, but in the present invention, it is a copolymer of the following (a) monomer and (b) monomer. It is preferable to use.
(A) Monomer (meth) Acrylic acid unsubstituted alkyl ester monomer (The number of carbon atoms of this unsubstituted alkyl group is 1 to 12).
(B) Monomer At least one of a vinyl-based monomer and a (meth) acrylic-based monomer having one or more groups selected from a hydroxyl group, a carboxyl group, an acid anhydride group and an alkoxysilyl group. In, "(meth) acrylic" means "acrylic" and / or "methacryl".

(A) The unsubstituted alkyl ester monomer of (meth) acrylic acid of the monomer is to maintain the cohesive force at high temperature because the cohesive force of the pressure-sensitive adhesive may decrease when the alkyl group has a long chain form. The unsubstituted alkyl group has 1 to 12 carbon atoms, but 2 to 8 is preferable.
Specific examples of the monomer (a) include butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, n-propyl (meth) acrylate, and isopropyl (meth) acrylate. Examples thereof include t-butyl (meth) acrylate, pentyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, and these include two types even when used alone. The above may be used together.

(B) The monomer is a component that imparts cohesive force or adhesive strength by chemical bonding so that the cohesive force of the pressure-sensitive adhesive is not destroyed under high temperature or high temperature and high humidity conditions.
Specific examples of the monomer (b) include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, diethylene glycol mono (meth) acrylate, and dipropylene glycol mono (meth). ) A hydroxyl group-containing monomer such as acrylate; a carboxyl group-containing monomer such as (meth) acrylic acid, (meth) acrylic acid dimer, itaconic acid, maleic acid, and maleic acid anhydride; (meth) acryloxypropyltrimethoxy. Silane, (meth) acryloxypropyltriethoxysilane, (meth) acryloxypropylmethyldimethoxysilane, (meth) acryloxypropylmethyldiethoxysilane, (meth) acryloxymethyltrimethoxysilane, (meth) acryloxymethyltri Examples thereof include monomers containing an alkoxysilyl group such as ethoxysilane, (meth) acryloxymethylmethyldimethoxysilane, and (meth) acryloxymethylmethyldiethoxysilane, and these monomers may be used alone or as 2 types. A seed or more may be used in combination, but it is preferable to use a monomer containing at least a hydroxyl group.

The amount of the (b) monomer used is preferably 0.1 to 10 parts by mass, more preferably 1 to 9 parts by mass, out of a total of 100 parts by mass of the (a) monomer and the (b) monomer. (B) When the amount of the monomer used is 0.1 parts by mass or more, cohesive fracture is unlikely to occur under high temperature and high humidity, while when it is 10 parts by mass or less, surface transfer and fluidity due to a decrease in compatibility are reduced. It is possible to suppress the decrease in stress relaxation capacity due to the decrease in the amount and the increase in the cohesive force.

In the present invention, in order to adjust the glass transition temperature of the pressure-sensitive adhesive composition and impart other functionality during the production of an acrylic polymer having a crosslinkable functional group, other copolymerizability is required. Further monomers can be used.
Specific examples of other copolymerizable monomers include acrylonitrile, styrene, glycidyl (meth) acrylate, vinyl acetate and the like. The blending ratio of the other copolymerizable monomers is preferably 0.1 to 9.9 parts by mass, more preferably 0.5 to 8 parts by mass, out of 100 parts by mass of all the monomers to be copolymerized.

The (meth) acrylic polymer used in the present invention because the viscoelastic properties of the pressure-sensitive adhesive composition are determined mainly by the molecular weight, the molecular weight distribution, or the abundance of the molecular structure, particularly by the molecular weight. The molecular weight (weight average molecular weight: Mw) of is preferably 800,000 to 2,000,000, more preferably 900,000 to 1.9 million. Within such a range, desired viscoelastic properties can be obtained and the viscosity can be easily handled.
The weight average molecular weight is a standard polystyrene-equivalent value measured by gel permeation chromatography (GPC).

Such a (meth) acrylic polymer can be produced through a normal radical copolymerization process.
In the present invention, the polymerization method of the polymer is not particularly limited, and the polymer can be produced by a general method such as a solution polymerization method, a photopolymerization method, a bulk polymerization method, a suspension polymerization method, and an emulsion polymerization method. Among these, the solution polymerization method is preferable from the viewpoint of productivity, and it is particularly preferable to add the initiator in a state where the monomers are uniformly mixed. In this case, the polymerization temperature is preferably 50 to 140 ° C., and the reaction time is preferably 1 to 24 hours.

Specific examples of the initiator include di-tert-butyl peroxide, benzoyl peroxide, lauryl peroxide, tert-butyl peroxybenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, dipropylperoxydicarbonate, and tert. Peroxides such as -butylperoxyneodecanoate, tert-butylperoxypivalate, (3,5,5-trimethylhexanoyl) peroxide; azobisisobutyronitrile, azobisvaleronitrile, 1, 1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl Examples thereof include azobis compounds such as -2,2'-azobis (2-methylpropionate) and 2,2'-azobis (2-hydroxymethylpropionitrile), or high molecular weight azo polymerization initiators, which are used alone. It may be used in combination of two or more kinds.
The initiator is usually used in an amount of 0.01 to 10 parts by mass with respect to 100 parts by mass of the total amount of the monomers.

(B) Blocked Isocyanate Silane Compound The blocked isocyanate silane compound of the component (B) is a component that acts as an adhesive modifier of the pressure-sensitive adhesive composition, and is represented by the following formula (1) in the present invention. Organosilicon compounds having a blocked isocyanate group are preferred.
In addition to the blocked isocyanate silane alone, the structure in which the hydrolyzable silyl group is partially hydrolyzed and the partially hydrolyzed condensate that is further intermolecularly condensed to form an oligomer exhibit the same performance. It can be used as an adhesive modification component of the present invention.

In the formula (1), R ¹ independently represents an alkyl group having 1 to 8 carbon atoms, L represents a divalent linking group, and X represents −O− or −NR ^2−. , Y represent a hydrogen atom or a monovalent organic group, and R ² represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a group capable of combining with Y to form a ring structure. m represents an integer of 1 to 3, preferably 3.

The alkyl group having 1 to 8 carbon atoms of R ¹ may be linear, branched or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert. -Butyl, n-pentyl, neopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl group and the like can be mentioned, with methyl and ethyl groups being preferred.

Specific examples of the divalent linking group of L include an alkylene group, -O-, -S-, -NR-, CO-, -COO-, -NRCO-, -SO _2-, and a combination thereof. Can be mentioned. Here, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and a hydrogen atom is preferable. Examples of the alkyl group include those having 1 to 4 carbon atoms among the alkyl groups exemplified above.
_{Among these,-(CH 2} ) _n- (n is 1 to 10, preferably 1 to 6, more preferably 1) as a divalent linking group from the viewpoint of availability of a raw material for producing an organosilicon compound. An alkylene group represented by (an integer of ~ 4), or _{one or more methylene units of this-(CH 2} ) _n- is -O-, -S-, -NH-, -CO- and -COO-. A group substituted with is preferable, and − (CH ₂ ) ₃ − (trimethylene group) is more preferable.

X in formula (1) -O- or -NR ² - is but a group which forms a part of the protective groups of the blocked isocyanate silane compound, since desorbed by heating, the present invention is not particularly limited No.
In −NR ² − of ^{X, R 2} represents a group that can be bonded to a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or Y to form a ring structure.
Examples of the alkyl group having 1 to 8 carbon atoms of R ^{2 include the same groups as those exemplified in R 1} above, but among them, a linear or branched alkyl group having 1 to 5 carbon atoms is preferable, and methyl. Groups or ethyl groups are more preferred.
In −NR ² −, when R ² represents a group capable of binding to Y to form a ring structure, −NR ² − is one that forms a heterocyclic structure with Y in the formula (1). preferable. The heteroatom in such a heterocyclic structure preferably contains two or more nitrogen atoms, and more preferably contains two nitrogen atoms. As the heterocyclic structure, a 5-membered ring or a 6-membered ring structure is preferable, and a 5-membered ring structure is more preferable.

Y in the formula (1) is a hydrogen atom or a monovalent organic group, but is a group forming a part of the protecting group of the blocked isocyanate silane compound and is desorbed by heating, so that it is not particularly limited. No.
Specific examples of the monovalent organic group of Y include a monovalent hydrocarbon group having a substituent having 1 to 20 carbon atoms and an −OH group (where X is −O−). Excludes), N = R ⁵ (R ⁵ represents an alkylidene group having 1 to 10 carbon atoms which may be substituted with an aryl group having 6 to 20 carbon atoms) and the like.
The monovalent hydrocarbon group having 1 to 20 carbon atoms may be linear, branched or cyclic, and may be an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or carbon. Examples thereof include an aralkyl group having 7 to 20 atoms.
Specific examples of the above alkyl group include n-nonyl, n-decyl, undecylic, dodecyl, tridecylic, and icosyl groups in addition to the group exemplified in ^{R 1.}
Specific examples of the aryl group include phenyl, naphthyl groups and the like.
Specific examples of the above-mentioned aralkyl group include benzyl, phenylethyl group and the like.
Further, in these groups, at least a part of the hydrogen atom may be substituted with another substituent, and examples of the other substituent include a carboxyl group, an ester group, a hydroxyl group and the like.
The alkylidene group having 1 to 10 carbon atoms which may be substituted with an aryl group having 6 to 20 carbon atoms or a heteroaryl group in R ^{5 may be linear, branched or cyclic, and may be any of the linear, branched and cyclic groups.} Specific examples include methylidene, phenylmethylidene, diphenylmethylidene, ethylidene, propyridene, propan-2-iriden, butylidene, butane-2-iriden, pentylidene, 4-methylpentane-2-iriden, hexylidene, cyclohexylidene, Examples thereof include heptylidene, octylidene, nonylidene, and decylidene groups.
Specific examples of the heteroaryl group having 6 to 20 carbon atoms include pyrrole-1-yl, 1H-pyrrole-2-yl, imidazole-1-yl, imidazol-2-yl, pyrazole-1-yl, and pyrazole-. Examples thereof include 3-yl, pyridin-2-yl, and pyridin-3-yl groups.

In particular, the blocked isocyanate silane compound represented by the above formula (1) is preferably represented by the following formula (2) or (3).

（式中、Ｒ¹、Ｒ²、Ｙおよびｍは、上記と同じ意味を表し、Ｒ³およびＲ⁴は、それぞれ独立して、水素原子または１価の有機基を表すが、Ｒ³とＲ⁴またはＲ²とＹが互いに連結して環構造を形成していてもよい。）

(In the formula, R ¹ , R ² , Y and m have the same meanings as above, and R ³ and R ⁴ independently represent a hydrogen atom or a monovalent organic group, but R ³ and R have their respective meanings. ⁴ or R ² and Y may be connected to each other to form a ring structure.)

Examples of the ^{monovalent organic group of R 3} and R ⁴ include a monovalent hydrocarbon group having 1 to 20 carbon atoms and a heteroaryl group having 6 to 20 carbon atoms.
Specific examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include the same groups as those exemplified in Y above, but the alkyl group having 1 to 20 carbon atoms and the aryl having 6 to 20 carbon atoms. Groups are preferred, and specific examples thereof include the same as above.
The heteroaryl group having 6 to 20 carbon atoms, the same groups as those exemplified above R ⁵ and the like.
Examples of ^{the ring structure formed by connecting R 3} and R ⁴ to each other include a cyclopentane ring and a cyclohexane ring.
In addition, these hydrocarbon groups and heteroaryl groups may have a substituent. Specific examples of the substituent include a carboxyl group, a hydroxyl group, an ester group and the like.
Examples of the group represented by R ³ -methylidene-R ^{4 include the alkylidene group exemplified in R 5} above, among which diphenylmethylidene, propane-2-iriden, butane-2-iriden and 4-methylpentane- 2-Ilidene and cyclohexylidene groups are preferred.

Specific examples of R ² and Y are the same as described above, but it is preferable that they are bonded to each other to form a ring structure together with a nitrogen atom. As the ring structure, a 5-membered ring or a 6-membered ring is preferable, and a 5-membered ring is more preferable.
Further, this ring structure preferably has two nitrogen atoms, more preferably an imidazole ring, a pyrazole ring, a 1,2,3-triazole ring, and a 1,2,4-triazole ring, and even more preferably a pyrazole ring. ..
The ring structure has a substituent such as an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a carboxyl group, a hydroxyl group, an ester group, and an oxo group (= O). May be good.
Suitable ring structures include, but are not limited to, the following:

Preferred specific examples of the blocked isocyanate silane compound of the component (B) include, but are not limited to, the following compounds.

The pressure-sensitive adhesive composition of the present invention contains 0.001 to 10 parts by mass of the component (B) with respect to 100 parts by mass of the component (A).
When the content of the component (B) is less than the lower limit value, the desired adhesive modification effect is not exhibited, and when the content exceeds the upper limit value, the effect is saturated, the cost-effectiveness is lowered, and originally. The effect of the silane coupling agent on improving the adhesion is increased, and the initial adhesion may become too high.

[Adhesive composition]
The pressure-sensitive adhesive composition of the present invention contains the above-mentioned components (A) and (B) as essential components, but preferably further contains (C) a polyfunctional cross-linking agent. The polyfunctional cross-linking agent of the component (C) plays a role of enhancing the cohesive force of the pressure-sensitive adhesive by reacting with the carboxyl group, the hydroxyl group and the like of the component (A).
The content of the component (C) is not particularly limited, but in consideration of appropriately increasing the cohesive force of the pressure-sensitive adhesive, 0.01 to 10 parts by mass with respect to 100 parts by mass of the component (A). It is preferably 0.05 to 5 parts by mass.

Examples of the polyfunctional cross-linking agent include isocyanate-based, epoxy-based, aziridine-based, and metal chelate-based cross-linking agents. Among them, isocyanate-based cross-linking agents are preferable in consideration of ease of use.
Examples of the isocyanate-based cross-linking agent include polyisocyanate compounds having two or more isocyanate groups in one molecule, and specific examples thereof include tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoform diisocyanate, and tetra. Examples thereof include methylxylylene diisocyanate, naphthalene diisocyanate, and reactants of these with polyols such as trimethylolpropane (trimethylolpropanetrilenedisocyanate adduct, etc.), which may be used alone or in combination of two or more. May be good.

Examples of the epoxy-based cross-linking agent include polyglycidyl compounds having two or more glycidyl groups in one molecule, and specific examples thereof include ethylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, N, N, N'. , N'-tetraglycidyl ethylenediamine, glycerin diglycidyl ether, glycerin triglycidyl ether, polyglycerin polyglycidyl ether, sorbitol-based polyglycidyl ether, etc., which may be used alone or in combination of two or more. May be good.

Examples of the aziridine-based cross-linking agent include polyaziridine compounds having two or more aziridine groups in one molecule, and specific examples thereof include N, N'-toluene-2,4-bis (1-aziridinecarboxide). , N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxide), triethylenemelamine, bisisoprotaloyl-1- (2-methylaziridine), tri-1-aziridinylphosphine oxide, etc. These may be used alone or in combination of two or more.
Specific examples of the metal chelate-based cross-linking agent include compounds in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, and vanadium is coordinated with acetylacetone or ethyl acetoacetate. It may be used alone or in combination of two or more.

Further, (D) a tackifying resin can be added to the pressure-sensitive adhesive composition of the present invention in order to adjust the pressure-sensitive adhesive performance.
The content of the component (D) is not particularly limited, but from the viewpoint of sufficiently exerting the added effect and preventing a decrease in cohesiveness, 1 per 100 parts by mass of the component (A). ~ 100 parts by mass is preferable, and 5 to 90 parts by mass is more preferable.
Specific examples of the tackifying resin include (hydrocarbonated) hydrocarbon resin, (hydrogenated) rosin resin, (hydrogenated) rosin ester resin, (hydrogenated) terpene resin, (hydrogenated) terpene phenol resin, and polymerization. Examples thereof include rosin resin and polymerized rosin ester resin, which may be used alone or in combination of two or more.

In addition to the above components, the pressure-sensitive adhesive composition of the present invention requires low molecular weight substances such as a plasticizer and a leveling agent, an epoxy resin, a curing agent, and the like, as long as the object of the present invention is not impaired. It can be blended as an additional component depending on the situation, and an ultraviolet stabilizer, an antioxidant, a decolorizing agent, a reinforcing agent, a filler, a defoaming agent, a surfactant and the like can be added according to a general purpose. can.

The pressure-sensitive adhesive composition of the present invention can be obtained, for example, by mixing the above-mentioned essential components and optional components by a usual method.
The mixing conditions are not particularly limited, but are preferably 10 minutes to 10 hours at 10 to 150 ° C. In this case, even if the blocked isocyanate silane compound of the component (B) is added in the compounding step after polymerizing the acrylic polymer of the component (A), it is still in the manufacturing process of the acrylic polymer of the component (A). Even if it is added, it has the same effect.
Further, the polyfunctional cross-linking agent of the component (C) enables uniform coating when the functional group cross-linking reaction of the cross-linking agent hardly occurs in the compounding process of the pressure-sensitive adhesive composition. After coating, the process of drying and aging forms a crosslinked structure, and an elastic and cohesive pressure-sensitive adhesive layer is obtained.

The pressure-sensitive adhesive composition of the present invention thus obtained is applied to an adherend such as a glass plate, a plastic film, or paper, preferably at 25 to 150 ° C. and 20 to 90% RH for 5 minutes to 5 hours. , More preferably, it can be cured at 40 to 80 ° C. and 25 to 60% RH for 10 minutes to 3 hours to form a pressure-sensitive adhesive layer.

The pressure-sensitive adhesive composition of the present invention is preferably used after sufficiently removing components that induce bubbles such as volatile components and reaction residues inside.
When the crosslink density and molecular weight are excessively low and the elastic modulus of the pressure-sensitive adhesive layer is too low, small bubbles existing between the adherend such as a glass plate and the pressure-sensitive adhesive layer become large in a high temperature state. Scatterers will be formed inside the pressure-sensitive adhesive layer. Further, when the pressure-sensitive adhesive layer having an excessively large elastic modulus is used for a long period of time, a peeling phenomenon occurs at the terminal portion of the pressure-sensitive adhesive layer (sheet) due to an excessive cross-linking reaction.

Further, when considering the balance between the cohesive force of the pressure-sensitive adhesive layer and the adhesive durability, the cross-linking density of the pressure-sensitive adhesive layer is preferably 5 to 95% by mass, more preferably 7 to 93% by mass. The cross-linking density is a value obtained by mass% of the amount of a portion having a cross-linked structure that is not dissolved in a solvent by a generally known method for measuring the gel content of a pressure-sensitive adhesive.

[Adhesive polarizing plate]
The pressure-sensitive adhesive polarizing plate of the present invention has a polarizing film or a polarizing element, and a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition attached to one or both sides of the polarizing film or the polarizing element.
The polarizing film or polarizing element constituting the polarizing plate is not particularly limited, and conventionally known ones can be appropriately selected and used.
Specific examples of the polarizing film include a film obtained by adding a polarizing component such as iodine or a heterochromatic dye to a film made of a polyvinyl alcohol-based resin and stretching the film. The thickness of the polarizing film is not limited, and a normal thickness can be adopted.
As the polyvinyl alcohol-based resin, polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, saponified products of ethylene / vinyl acetate copolymer and the like are used.

In the present invention, there is no particular limitation on the method of forming the pressure-sensitive adhesive layer on the polarizing film.
For example, a method in which the pressure-sensitive adhesive composition is directly applied to the surface of a polarizing film using a bar coater or the like and dried, or the pressure-sensitive adhesive composition is once applied to the surface of a peelable substrate and dried, and then this peelability is achieved. Examples thereof include a method in which the pressure-sensitive adhesive layer formed on the surface of the substrate is transferred to the surface of the polarizing film and then aged. In this case, drying is preferably 25 to 150 ° C. and 20 to 90% RH for 5 minutes to 5 hours, and aging is preferably 25 to 150 ° C. and 20 to 90% RH for 5 minutes to 5 hours.

The thickness of the pressure-sensitive adhesive layer is not particularly limited, but 0.01 to 100 μm is preferable, and 0.1 to 50 μm is more preferable, considering that the effect required for the pressure-sensitive adhesive layer is appropriately exhibited.

The polarizing film (adhesive polarizing plate) having the pressure-sensitive adhesive layer of the present invention thus obtained has additional functions such as a protective layer, a reflective layer, a retardation plate, an optical viewing angle compensation film, and a brightness improving film. One or more layers can be laminated.

In particular, on both sides of a polarizing film having an adhesive layer, a cellulose-based film such as triacetyl cellulose; a polycarbonate film; a polyester-based film such as a polyethylene terephthalate film; a polyether sulfone-based film; It is preferable to form a multilayer film or the like in which a protective film such as a polyolefin film is laminated. At this time, the thickness of these protective films is not particularly limited, and a normal thickness may be adopted.

[Liquid crystal display device]
The adhesive polarizing plate of the present invention can be applied to a general liquid crystal display device in general, and the type of the liquid crystal panel is not particularly limited. In particular, a liquid crystal display device including a liquid crystal panel in which the adhesive polarizing plate of the present invention is bonded to one side or both sides of a liquid crystal cell in which a liquid crystal is enclosed between a pair of glass substrates is preferable.

In addition to the above-mentioned polarizing film, the pressure-sensitive adhesive composition of the present invention includes industrial sheets, particularly reflective sheets, structural pressure-sensitive adhesive sheets, photographic pressure-sensitive adhesive sheets, lane-displaying pressure-sensitive adhesive sheets, optical pressure-sensitive adhesive products, electronic components, and the like. , Can be used for various purposes.
It can also be applied to laminated products having a multi-layer structure, that is, general commercial adhesive sheet products, medical patches, heat activation, and the like, which have the same concept of action.

Hereinafter, the present invention will be described in more detail with reference to synthetic examples, examples and comparative examples, but the present invention is not limited to these examples.

[1] Synthesis of (meth) acrylic polymer [Synthesis Example 1]
98.1 g of n-butyl acrylate (BA), 0.6 g of acrylic acid (AA), 2-hydroxyethyl methacrylate (2-HEMA) in a 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer. ) 1.3 g was charged, and 100 g of ethyl acetate was charged as a solvent and dissolved. Then, nitrogen gas bubbling was performed for 1 hour to remove oxygen, and the inside of the reaction system was replaced with nitrogen and maintained at 62 ° C. 0.03 g of azobisisobutyronitrile as a polymerization initiator was added thereto with stirring, and the mixture was reacted at 62 ° C. for 8 hours to obtain a (meth) acrylic polymer (A-1).

[2] Preparation of Adhesive Composition and Formation of Adhesive Layer [Example 1]
The (meth) acrylic polymer (A-1) obtained in Synthesis Example 1, the compound shown in B-1 below, and (C) trimethylolpropane tolylene diisocyanate adduct (TDI) are blended in the composition shown in Table 1. They were mixed to prepare a pressure-sensitive adhesive composition.

[Examples 2 to 7, Comparative Examples 1 to 6]
A pressure-sensitive adhesive composition was prepared in the same manner as in Example 1 except that the blending amount and type of the component (B) were changed as shown in Table 1.

The abbreviations in Table 1 are as follows.
B-1: Silane compound represented by the above formula (4-a) B-2: Silane compound represented by the above formula (4-b) B-3: Silane represented by the above formula (8-a) Compound B-4: Silane compound represented by the above formula (8-b) B-5: Silane compound represented by the above formula (8-a) B-6: Represented by the above formula (8-b) Silane compound B'-1: Glycydoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Industry Co., Ltd., KBM-403)
B'-2: Silane compound represented by the following formula

B'-3: Double-ended alkoxysilyl-modified PO-type polyether compound (manufactured by Kaneka Corporation, Cyril SAT10)
TDI: Trimethylolpropane tolylene diisocyanate adduct

The pressure-sensitive adhesive compositions obtained in the above Examples and Comparative Examples were coated on a release paper and dried to obtain a uniform pressure-sensitive adhesive layer of 25 μm. The pressure-sensitive adhesive layer thus produced was pressure-bonded to an iodine-based polarizing plate having a thickness of 185 μm, and then the obtained polarizing plate was cut and used for each evaluation.
The manufactured polarizing plate test pieces were evaluated for durability, glass adhesiveness, reworkability, and changes in adhesive strength under high temperature and high temperature and humidity through the evaluation test methods shown below. The results are shown in Tables 2 and 3.

Evaluation test (1) Durability A polarizing plate (90 mm x 170 mm) coated with an adhesive is attached to a glass substrate (110 mm x 190 mm x 0.7 mm) with the optical absorption axes crossed on both sides, and the test piece is attached. Obtained. At this time, the applied pressure was about 5 kgf / cm ² , and the work was performed in a clean room so as not to generate air bubbles or foreign substances.
In order to evaluate the moisture resistance and heat resistance characteristics of this test piece, after leaving it for 1,000 hours under the condition of 60 ° C./90% relative humidity, the presence or absence of bubbles and peeling was confirmed. As for the heat resistance characteristics, after leaving it at 80 ° C./30% relative humidity for 1,000 hours, the state of bubbles and peeling was observed. Before evaluating the state of the test piece, it is allowed to stand at room temperature (25 ° C.) for 24 hours. The results are shown in Table 2.
The evaluation criteria for durability evaluation are as follows.
○: No bubbles or peeling phenomenon △: Slight bubbles or peeling phenomenon ×: Many bubbles or peeling phenomena

(2) Changes in glass adhesive strength and adhesive strength under high temperature and high temperature and high humidity conditions A polarizing plate coated with an adhesive is aged at room temperature (23 ° C./60% RH) for 7 days, and then the polarizing plate is used for 1 each. It was cut into an inch × 6 inch size and attached to 0.7 mm thick non-alkali glass using a 2 kg rubber roller. After storage at room temperature, the initial adhesive strength was measured 1 hour later, then aged at 50 ° C. for 4 hours, then stored at room temperature for 1 hour, and then the adhesive strength was measured. The results are shown in Table 2.
Further, in order to see the degree of increase in adhesive strength under high temperature and high temperature and high humidity conditions, the adhesive strength was measured by aging at 100 ° C./30% RH for each time and then allowing to cool at room temperature for 1 hour. The results are shown in Table 3.
At this time, a tensile tester was used to measure the adhesive strength, and the peel strength (gf / in) was measured at a speed of 300 mm / min and an angle of 180 °.

(3) Reworkability After attaching a polarizing plate (90 mm × 170 mm) coated with an adhesive to a glass substrate (110 mm × 190 mm × 0.7 mm), 1 hour has passed at room temperature (initial adhesive strength) and 50 ° C. × After aging for 4 hours and allowing to cool at room temperature for 1 hour, the polarizing plate was peeled off from the glass. The results are shown in Table 2.
The evaluation criteria for reworkability are as follows.
◯: Easy to peel off △: Slightly difficult to peel off ×: Cannot be peeled off, broken glass

As shown in Tables 2 and 3, it can be seen that in Comparative Example 1, since the blocked isocyanate silane compound was not blended, sufficient adhesiveness was not exhibited after heat curing.
Comparative Example 2 is a case where an epoxy silane coupling agent, which is an existing technique, is used, and it can be seen that the initial adhesive strength is too high and reworkability is not exhibited.
Comparative Examples 3 and 4 are existing silane materials that contribute to reworkability and adhesion after curing, but it can be seen that the final adhesion strength after curing is insufficient and reliability is lacking.
In Comparative Example 5, the effect is insufficient because the amount of the blocked isocyanate silane compound component used is too small, while in Comparative Example 6, since the amount of the component is too large, unnecessary adhesion is developed from the initial stage. It can be seen that the reworkability is insufficient.
On the other hand, in Examples 1 to 7, since the blocked isocyanate silane compound is used in a predetermined amount, it can be seen that the problems caused in each Comparative Example are solved.
From the above, it can be seen that the composition of the present invention is an adhesive composition having excellent initial reworkability, exhibiting sufficient adhesive strength with glass by high temperature and high temperature and high humidity treatment, and excellent in long-term durability. ..

Claims (8)

It contains (A) a (meth) acrylic polymer having a crosslinkable functional group and (B) a blocked isocyanate silane compound.
The crosslinkable functional group is one or more groups selected from a hydroxyl group, a carboxyl group, an acid anhydride group, and an alkoxysilyl group.
The component (B) is contained in an amount of 0.001 to 10 parts by mass with respect to 100 parts by mass of the component (A).
The adhesive characterized by the above-mentioned (B) blocked isocyanate silane compound being represented by the following formulas (2), (8-a), (8-b), (9-a) or (9-b). Agent composition.

(In the formula, R ¹ independently represents an alkyl group having 1 to 8 carbon atoms, and R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group, but R ³ And R ⁴ may be linked to each other to form a ring structure, where m represents an integer of 1 to 3, Me means a methyl group, and Et means an ethyl group.) The (meth) acrylic polymer having (A) a crosslinkable functional group is a copolymer of (a) a monomer and (b) a monomer.
The (a) monomer is an unsubstituted carbon atom number 1 to 12 alkyl ester monomer of (meth) acrylic acid.
The monomer (b) is at least one of a vinyl-based monomer and a (meth) acrylic-based monomer having one or more groups selected from a hydroxyl group, a carboxyl group, an acid anhydride group and an alkoxysilyl group. can be,
The pressure-sensitive adhesive composition according to claim 1, wherein the amount of the (b) monomer in 100 parts by mass of the total of the (a) and (b) monomers is 0.1 to 10 parts by mass. The monomer (a) is butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, t-butyl. 2. A monomer selected from the group consisting of (meth) acrylate, pentyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, and isononyl (meth) acrylate. The described pressure-sensitive adhesive composition. The monomer (b) is 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, diethylene glycol mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, (Meta) Acryloxypropyltrimethoxysilane, (Meta) Acryloxypropyltriethoxysilane, (Meta) Acryloxypropylmethyldimethoxysilane, (Meta) Acryloxypropylmethyldiethoxysilane, (Meta) Acryloxymethyltrimethoxysilane , (Meta) Acryloxymethyltriethoxysilane, (Meta) Acryloxymethylmethyldimethoxysilane, (Meta) Acryloxymethylmethyldiethoxysilane, (Meta) Acrylic acid, (Meta) Acrylic acid dimer, Itaconic acid, The pressure-sensitive adhesive composition according to claim 2 or 3, which is one or more monomers selected from the group consisting of maleic acid and maleic acid anhydride. (C) One or more polyfunctional cross-linking agents selected from the group consisting of isocyanate-based compounds, epoxy-based compounds, aziridine-based compounds, and metal chelate-based compounds are applied to 100 parts by mass of the component (A). The pressure-sensitive adhesive composition according to any one of claims 1 to 4, which contains 0.01 to 10 parts by mass. It has a polarizing film and an adhesive layer laminated on one or both sides of the polarizing film.
A pressure-sensitive polarizing plate in which the pressure-sensitive adhesive layer is formed from the pressure-sensitive adhesive composition according to any one of claims 1 to 5. The adhesive polarizing plate according to claim 6, further comprising one or more functional layers selected from a protective layer, a reflective layer, a retardation plate, an optical viewing angle compensating film, and a luminance improving film. A liquid crystal panel having a pair of glass substrates, a liquid crystal cell including a liquid crystal enclosed between them, and an adhesive polarizing plate according to claim 6 or 7, which is attached to one or both sides of the liquid crystal cell. Liquid crystal display including.