JP2015028607A - Active energy ray-curable adhesive for polarizing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable adhesive for a polarizing plate, which comprises a urethane (meth)acrylamide having a high curing rate, and which exhibits good wetting property and adhesiveness to polyvinyl alcohol-based polarizing films, various protective films, retardation films and optical compensation films, has a low viscosity and workability without inducing adhesion irregularity upon manufacturing a polarizing plate, and which has high adhesion strength, high heat resistance and excellent transparency.SOLUTION: An active energy ray-curable adhesive is prepared by compounding a urethane (meth)acrylamide synthesized from N-hydroxyalkyl (meth)acrylamide, as an essential component. A polarizing plate excellent in polarizing property, transparency and heat resistance can be manufactured by using the above adhesive and by bonding a polarizing film with a polarizing layer protective film and/or a retardation film, or with an optical compensation film, and curing the adhesive by irradiation with active energy rays.

Description

The present invention relates to an active energy ray-curable adhesive suitable for bonding a polyvinyl alcohol polarizing film and various protective films, retardation films, and optical compensation films when producing a polarizing plate. Specifically, the present invention relates to an active energy ray-curable adhesive containing urethane (meth) acrylamide and a polarizing plate produced using the active energy ray-curable adhesive.

A polarizing film is an indispensable material for a liquid crystal display device, and is generally produced by adsorbing and blending iodine (I) compound molecules mainly containing polyvinyl alcohol (PVA). The role of the polarizing film is to allow the light in the polarization direction to pass and block the light other than the polarization direction. However, since the PVA-based film is easily affected by moisture and heat, it can be decomposed or dimensionally changed. The polarization performance may be deteriorated. In order to prevent this, a protective film or the like is bonded to the surface (one side or both sides) of the PVA polarizing film using an adhesive. A laminate of (protective film / adhesive / PVA polarizing film / adhesive / protective film) produced in this manner is a polarizing plate that is usually used.

Conventionally, aqueous solutions of polyvinyl alcohol resins (PVA adhesives) have been widely used as adhesives used for bonding PVA polarizing films and protective films. Further, as a protective film, a film made of a triacetyl cellulose (TAC) cellulose derivative which is transparent and has a small retardation and is excellent in adhesiveness with a PVA polarizing film and a PVA adhesive is generally used ( Patent Documents 1 to 3). However, since the TAC film has high moisture permeability, it is easy to operate the adhesive drying after being bonded by wet lamination of the PVA adhesive aqueous solution. On the other hand, the dimensional change of the polarizing plate due to temperature and humidity is large, and uneven brightness occurs. There was a problem that the change in optical characteristics was large.

As a method for solving such a problem, instead of TAC, a transparent film made of a low moisture-permeable cyclic polyolefin resin, norbornene resin, acrylic resin, polycarbonate resin or the like is being used on one or both sides of the PVA polarizing film. However, since the moisture permeability is low, it is necessary to use a protective film and a polarizing film, and after bonding together via an aqueous PVA solution as an adhesive, heating and drying are required to remove water. There was a problem that it was consumed and productivity was low. Moreover, in order to prevent the deterioration of the optical characteristics of the polarizing plate due to heating, a complicated drying process such as heating in several steps is required (Patent Document 4). Further, these protective films have a strong hydrophobicity, and there is a problem that sufficient adhesive strength cannot be obtained when bonding with a hydrophilic PVA polarizing film or PVA adhesive. Therefore, in order to improve the adhesiveness, various modification methods have been examined both in the protective film and in the PVA adhesive. For example, cyclic polyolefin modified with styrene or acrylate ester (Patent Document 5), TAC modified with cyclopentanone (Patent Document 6), alkali treatment of acrylic film or polycarbonate film, corona treatment of norbornene film (Patent Document 7), A protective film coating treatment with water-soluble cellulose (Patent Document 8), an adhesive composed of a modified PVA and an aqueous crosslinking agent (Patent Documents 9 and 10), and the like have been proposed. However, these reforming methods increase equipment costs, complicate the production process and quality control, greatly reduce productivity, and are not sufficient in adhesive strength.

For these reasons, many proposals have been made to use cross-linked adhesives such as isocyanate compounds and active energy ray-curable adhesives such as UV and EB as substitutes for aqueous PVA solutions that are aqueous adhesives. . By the way, many isocyanate cross-linking adhesives are water-dispersed or solvent-based, and after bonding the polarizing film and the protective film, the drying process by heating cannot be omitted, and the cross-linking reaction is completed, In many cases, aging is required (Patent Documents 11 and 12). On the other hand, active energy ray-curable adhesives require special UV and EB irradiation equipment, but they are particularly advantageous for high-speed production of polarizing plates because they are solvent-free and can be firmly bonded in a short time. It is actively done. For example, a branched polyester having at least six (meth) acrylate groups using hydroxyethylacrylamide, acryloylmorpholine (Patent Document 13), or non-urethane polyfunctional monomer such as ditrimethylolpropane tetraacrylate (Patent Document 14) Adhesives prepared in combination with polyfunctional monomers (Patent Document 15) or polyfunctional acrylamides (Patent Document 16) such as methylenebisacrylamide have been reported. Furthermore, urethane acrylate and amide and ester acrylic monomers An adhesive made of a mixture of bodies is disclosed (Patent Documents 17 and 18).

However, since hydroxyethyl acrylamide has a structure having both a strongly polar hydroxyl group and an amide group, for a PVA polarizing film having a hydroxyl group on the surface, a highly hydrophilic TAC protective film, a retardation film, and an optical compensation film, Excellent wettability and adhesion, but very low wettability and adhesion to various films made of hydrophobic cyclic polyolefin resin, norbornene resin, acrylic resin, polycarbonate resin, etc. It was. As described in Patent Documents 13 to 18, by improving the adhesion to the hydrophobic protective film and the like by adding the second component and the third component such as a polyfunctional monomer, hydroxyethyl acrylamide has been observed. Is a highly hydrophilic monomer, so there was a problem in the water resistance of the polarizing plate after bonding. Moreover, the adhesiveness with respect to a hydrophobic protective film etc. cannot fully be improved, but adhesive strength is still low. In particular, in the proposal of Patent Document 15, the branched polyester polyfunctional monomer having at least six (meth) acrylate groups has high hydrophobicity, so that it is incompatible with hydroxyethylacrylamide having high hydrophilicity, and thus obtained polarized light. There is a problem that the transparency of the plate is significantly reduced.

In addition, as an active energy ray-curable adhesive for polarizing plates having good adhesion and water resistance, a hydroxyl group-containing monofunctional monomer and an isocyanate compound are mixed and cured with active energy rays (Patent Document 19, 20, 21), and the use of a compound obtained by reacting the hydroxyl group-containing monomer with an isocyanate compound has been proposed (Patent Document 21).

However, although the adhesive for polarizing plate can improve the adhesion and water resistance to some extent, the addition reaction between the hydroxyl group-containing monomer and the isocyanate compound gradually proceeds even after the curing reaction by active energy ray irradiation is completed. When a long cured product is formed into a take-up roll shape, curling occurs due to dark reaction (post-polymerization) during storage, and there is a problem that productivity in the processing step is remarkably reduced. Even when using a compound obtained by reacting a hydroxyl group-containing monomer with an isocyanate compound, even if the isocyanate group ratio is adjusted to be too small so that the hydroxyl group-containing monomer remains, it remains slightly. As the unreacted isocyanate compound reacts with the hydroxyl group-containing monomer gradually, an increase in viscosity or the like occurs, the product composition lacks stability, and it is difficult to continue to develop a uniform cured state.

Thus, there was no adhesive having both high adhesion and water resistance for both the hydrophobic protective film and the hydrophilic PVA film.

JP 2004-109657 A JP 2007-241152 A JP 2009-242786 A JP 2005-309394 A JP 2009-108286 A JP 2007-004123 A JP 2009-169333 A JP 2011-057985 A JP 2009-237388 A JP 2009-092857 A JP 2003-177247 A JP 2010-117516 A JP 2008-287207 A JP 2010-78700 A JP 2010-78699 A JP 2010-77199 A Japanese Patent Laid-Open No. 04-159317 JP 2008-174667 A JP 2011-218616 A JP 2012-82288 A JP 2010-054720 A

The present invention has good wettability and adhesion to a PVA polarizing film and various protective films, retardation films, and optical compensation films when producing a polarizing plate. It is an object of the present invention to provide an active energy ray-curable adhesive for polarizing plates, which has both heat resistance and excellent transparency and has a high curing rate.
Moreover, this invention makes it a subject to produce and provide the polarizing plate excellent in polarizing property, heat resistance, durability, and moisture resistance using such an active energy ray hardening adhesive.

As a result of intensive studies to solve these problems, the present inventor has found an active energy ray-curable adhesive containing urethane (meth) acrylamide, and the polarizing film and the polarizing layer are protected through the adhesive. The above-mentioned problems were solved by laminating a film, a retardation film, or an optical compensation film, and curing the film by irradiation with active energy rays, thereby reaching the present invention.

（３）化合物（Ａ）と化合物（Ｂ）の付加反応は、化合物（Ａ）の水酸基の合計に対して化合物（Ｂ）のイソシアネート基の合計は当量以下で行うことを特徴とする前記（１）または（２）に記載の偏光板用接着剤、
（４）化合物（Ａ）が、Ｎ−ヒドロキシアルキレン（メタ）アクリルアミド、Ｎ，Ｎ−ジヒドロキシアルキレン(メタ)アクリルアミド、及びＮ−アルキル−Ｎ−ヒドロキシアルキレン(メタ)アクリルアミドからなる群から選ばれる１種または２種以上の化合物であることを特徴とする前記（１）乃至（３）のいずれか一項に記載の偏光板用接着剤、
（５）化合物（Ｂ）は１分子内に１個のイソシアネート基を有する単官能イソシアネート、及び／又は、１分子内に２個以上のイソシアネート基を有する多官能イソシアネートであることを特徴とする前記（１）乃至（４）のいずれか一項に記載の偏光板用接着剤、
（６）多官能イソシアネートは、脂肪族、芳香族、脂環族またはこれらの多量体、アダクトタイプであることを特徴とする前記（１）乃至（５）のいずれか一項に記載の偏光板用接着剤、
（７）１分子中に１個以上のイソシアネート基を有する化合物（Ｂ）は、１分子内に１個以上の水酸基を有する化合物と１分子内に２個以上のイソシアネート基を有する化合物との付加反応物であり、かつ、水酸基の合計に対してイソシアネート基の合計は当量以上であることを特徴とする前記（１）乃至（６）のいずれか一項に記載の偏光板用接着剤、
（８）１分子中に１個以上のイソシアネート基を有する化合物（Ｂ）は、１分子内に１個以上のカルボキシル基を有する化合物と１分子内に２個以上のイソシアネート基を有する化合物との付加反応物であり、かつ、カルボキシル基の合計に対してイソシアネート基の合計は当量以上であることを特徴とする前記（１）乃至（６）のいずれか一項に記載の偏光板用接着剤、
（９）１分子中に１個以上のイソシアネート基を有する化合物（Ｂ）は、１分子内に１個以上のチオール基を有する化合物と１分子内に２個以上のイソシアネート基を有する化合物との付加反応物であり、かつ、チオール基の合計に対してイソシアネート基の合計は当量以上であることを特徴とする前記（１）乃至（６）のいずれか一項に記載の偏光板用接着剤、
（１０）１分子中に１個以上のイソシアネート基を有する化合物（Ｂ）は、１分子内に１個以上のアミン基を有する化合物と１分子内に２個以上のイソシアネート基を有する化合物との付加反応物であり、かつ、アミン基の合計に対してイソシアネート基の合計は当量以上であることを特徴とする前記（１）乃至（６）のいずれか一項に記載の偏光板用接着剤、
（１１）前記ウレタン（メタ）アクリルアミドが、重量平均分子量２００乃至４，０００の単量体またはオリゴマーであることを特徴とする前記（１）乃至（１０）のいずれか一項に記載の偏光板用接着剤、
（１２）前記ウレタン（メタ）アクリルアミドが、重量平均分子量４，０００を超えて、かつ２００，０００以下のポリマーであることを特徴とする前記（１）乃至（１０）のいずれか一項に記載の偏光板用接着剤、
（１３）さらに水酸基を有するアクリルモノマー（Ｃ）を含有する前記（１）乃至（１２）のいずれかに記載の偏光板用接着剤、
（１４）さらにエポキシ基を有するアクリルモノマー（Ｄ）を含有する前記（１）乃至（１３）のいずれかに記載の偏光板用接着剤、
（１５）前記偏光板用接着剤中のウレタン（メタ）アクリルアミドと水酸基を含有するアクリルモノマー（Ｃ）の含有量比が、ウレタン（メタ）アクリルアミド／（Ｃ）が１０乃至６０重量％／４０乃至９０重量％であることを特徴とする偏光板用接着剤、
（１６）前記偏光板用接着剤中のウレタン（メタ）アクリルアミドとエポキシ基を含有するアクリルモノマー（Ｄ）の含有量比が、ウレタン（メタ）アクリルアミド／（Ｄ）が３０乃至９５重量％／５乃至７０重量％であることを特徴とする偏光板用接着剤、
（１７）偏光フィルムの少なくとも片面に透明樹脂からなる保護フィルムを貼り合せるために用いる活性エネルギー線硬化型偏光板用接着剤であって、該接着剤が前記（１）乃至（１６）のいずれかに記載の偏光板用接着剤により形成されていることを特徴とする偏光板
を提供するものである。 That is, the present invention
(1) An active energy ray-curable adhesive for polarizing plate used for bonding a protective film made of a transparent resin to at least one surface of a polarizing film made of a polyvinyl alcohol-based resin, wherein the adhesive is at least one ( An adhesive for polarizing plates, characterized by containing urethane (meth) acrylamide having a (meth) acryloyl group,
(2) The urethane (meth) acrylamide may be represented by the general formula [1] (R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ are the same or different and may be substituted with a hydrogen atom or a hydroxyl group. A linear or branched alkyl group having 1 to 6 carbon atoms, an aliphatic or aromatic ring having 3 to 6 carbon atoms, and R ₂ and R ₃ together with the nitrogen atom supporting them. To form a saturated or unsaturated 5- to 7-membered ring which may further contain an oxygen atom or a nitrogen atom, provided that R ₂ and R ₃ are hydrogen atoms at the same time, and R ₂ and R ₃ is obtained by an addition reaction of the compound (A) represented by the formula (A) except that it is not substituted with a hydroxyl group at the same time and a compound (B) having one or more isocyanate groups in one molecule. Characterized by the above ( The adhesive for polarizing plate according to),

(3) The addition reaction of the compound (A) and the compound (B) is carried out in such a manner that the total of isocyanate groups of the compound (B) is not more than the equivalent to the total of hydroxyl groups of the compound (A) (1 ) Or (2) the polarizing plate adhesive,
(4) The compound (A) is selected from the group consisting of N-hydroxyalkylene (meth) acrylamide, N, N-dihydroxyalkylene (meth) acrylamide, and N-alkyl-N-hydroxyalkylene (meth) acrylamide Or an adhesive for polarizing plate according to any one of (1) to (3), wherein the adhesive is a compound of two or more types,
(5) The compound (B) is a monofunctional isocyanate having one isocyanate group in one molecule and / or a polyfunctional isocyanate having two or more isocyanate groups in one molecule. (1) The adhesive agent for polarizing plates as described in any one of (4),
(6) The polarizing plate according to any one of (1) to (5), wherein the polyfunctional isocyanate is aliphatic, aromatic, alicyclic, or a multimer thereof, or an adduct type. Adhesives,
(7) Compound (B) having one or more isocyanate groups in one molecule is an addition of a compound having one or more hydroxyl groups in one molecule and a compound having two or more isocyanate groups in one molecule The adhesive for polarizing plates according to any one of (1) to (6), wherein the adhesive is a reaction product, and the total of isocyanate groups is equal to or greater than the total of hydroxyl groups,
(8) The compound (B) having one or more isocyanate groups in one molecule is composed of a compound having one or more carboxyl groups in one molecule and a compound having two or more isocyanate groups in one molecule. The adhesive for polarizing plates according to any one of (1) to (6), wherein the adhesive is an addition reaction product, and the total of isocyanate groups is equal to or more than the total of carboxyl groups. ,
(9) The compound (B) having one or more isocyanate groups in one molecule is composed of a compound having one or more thiol groups in one molecule and a compound having two or more isocyanate groups in one molecule. The adhesive for polarizing plates according to any one of (1) to (6), wherein the adhesive is an addition reaction product, and the total of isocyanate groups is equal to or greater than the total of thiol groups. ,
(10) The compound (B) having one or more isocyanate groups in one molecule is composed of a compound having one or more amine groups in one molecule and a compound having two or more isocyanate groups in one molecule. The adhesive for polarizing plates according to any one of (1) to (6), wherein the adhesive is an addition reaction product, and the total of isocyanate groups is equal to or greater than the total of amine groups. ,
(11) The polarizing plate according to any one of (1) to (10), wherein the urethane (meth) acrylamide is a monomer or oligomer having a weight average molecular weight of 200 to 4,000. Adhesives,
(12) The urethane (meth) acrylamide is a polymer having a weight average molecular weight of more than 4,000 and not more than 200,000, according to any one of (1) to (10), Adhesive for polarizing plate,
(13) The adhesive for polarizing plates according to any one of (1) to (12), further comprising an acrylic monomer (C) having a hydroxyl group,
(14) The polarizing plate adhesive according to any one of (1) to (13), further comprising an acrylic monomer (D) having an epoxy group,
(15) The urethane (meth) acrylamide / hydroxy group-containing acrylic monomer (C) content ratio in the polarizing plate adhesive is urethane (meth) acrylamide / (C) of 10 to 60% by weight / 40 to 90% by weight adhesive for polarizing plate,
(16) The content ratio of urethane (meth) acrylamide and acrylic monomer (D) containing an epoxy group in the adhesive for polarizing plate is 30 to 95% by weight of urethane (meth) acrylamide / (D). An adhesive for polarizing plate, characterized in that it is from 70 to 70% by weight,
(17) An active energy ray-curable polarizing plate adhesive used for bonding a protective film made of a transparent resin on at least one surface of a polarizing film, wherein the adhesive is any one of (1) to (16) The polarizing plate is characterized by being formed by the polarizing plate adhesive described in 1. above.

化合物（Ａ）に起因するアミド基を有するため、活性エネルギー線硬化速度が非常に速い上、表面に水酸基を有するＰＶＡ系偏光フィルムや親水性の高いＴＡＣ系保護フィルムや位相差フィルム、光学補償フィルムに対して、ぬれ性や密着性に優れている。また、１分子中に１個以上のイソシアネート基を有する化合物（Ｂ）に疎水性のセグメントを付与させることにより、化合物（Ａ）の課題点であった、疎水性である環状ポリオレフィン樹脂やノルボルネン樹脂、アクリル樹脂、ポリカーボネート樹脂等からなる各種フィルムに対するぬれ性や密着性の低さに起因する接着力の低下が改善され、親水性及び疎水性の両フィルムに対して優れた接着性を持つ。更に、該接着剤は、水酸基を有するアクリルモノマー並びにエポキシ基を有するモノマーを混合して使用することによって、接着性、耐水性の更なる向上が得られる。また、必要に応じて第３級アミン化合物、有機系イオン性化合物、硬化性の多官能化合物を混合して使用することによって様々な付加機能を提供することができる。例えば、特殊の位相差フィルムや光学補償フィルムに対するぬれ性、密着性の一層向上、耐水性の更なる改善、導電性や帯電防止性付与等の機能を提供することができる。 The active energy ray-curable adhesive for polarizing plates of the present invention has excellent wettability and adhesion to PVA polarizing films, various protective films, retardation films, and optical compensation films, and causes uneven adhesion. It has both high curing speed, high adhesive strength, high heat resistance and excellent transparency. The adhesive of the present invention has the general formula [1] (R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ are the same or different and may be substituted with a hydrogen atom or a hydroxyl group. A linear or branched alkyl group having 1 to 6 carbon atoms, an aliphatic or aromatic ring having 3 to 6 carbon atoms, and R ₂ and R ₃ together with the nitrogen atom supporting them. In addition, a saturated or unsaturated 5- to 7-membered ring which may further contain an oxygen atom or a nitrogen atom may be formed, provided that R ₂ and R ₃ are hydrogen atoms at the same time, and R ₂ and R ₃ Are not substituted with a hydroxyl group at the same time.) And at least one compound (A) obtained by an addition reaction between the compound (A) represented by (A) and a compound (B) having one or more isocyanate groups in one molecule. Ureta having a (meth) acryloyl group (Meth) are configured acrylamide as an essential component.

Since it has an amide group derived from the compound (A), the active energy ray curing rate is very fast, and a PVA polarizing film having a hydroxyl group on the surface, a highly hydrophilic TAC protective film, a retardation film, and an optical compensation film In contrast, it has excellent wettability and adhesion. In addition, by adding a hydrophobic segment to the compound (B) having one or more isocyanate groups in one molecule, a hydrophobic cyclic polyolefin resin or norbornene resin, which was a problem of the compound (A) In addition, a decrease in adhesive strength due to poor wettability and adhesion to various films made of acrylic resin, polycarbonate resin, etc. is improved, and excellent adhesion to both hydrophilic and hydrophobic films. Further, the adhesive can be further improved in adhesion and water resistance by using a mixture of an acrylic monomer having a hydroxyl group and a monomer having an epoxy group. Moreover, various additional functions can be provided by mixing and using a tertiary amine compound, an organic ionic compound, and a curable polyfunctional compound as required. For example, it is possible to provide functions such as wettability and adhesion to special retardation films and optical compensation films, further improvement of water resistance, and imparting conductivity and antistatic properties.

By using the active energy ray-curable adhesive for polarizing plates of the present invention, expensive special equipment, complicated drying processes, PVA polarizing films, various protective films, retardation films, optical compensation film surface modifications or anchors A polarizing plate excellent in transparency, polarization, heat resistance, durability, and moisture resistance can be easily produced and provided without requiring a coating process.

The present invention is described in detail below.
The active energy ray-curable adhesive of the present invention contains urethane (meth) acrylamide having at least one (meth) acryloyl group as an essential component.

The urethane (meth) acrylamide used in the present invention has the general formula [1] (R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ are the same or different and are substituted with a hydrogen atom or a hydroxyl group. Represents a straight or branched alkyl group having 1 to 6 carbon atoms, an aliphatic or aromatic ring having 3 to 6 carbon atoms, and R ₂ and R ₃ together with the nitrogen atom supporting them. To form a saturated or unsaturated 5- to 7-membered ring which may further contain an oxygen atom or a nitrogen atom, provided that R ₂ and R ₃ are simultaneously hydrogen atoms, and R ₂ And R ₃ are not substituted with a hydroxyl group at the same time.) And a compound (B) having one or more isocyanate groups in one molecule.

Examples of the compound (A) represented by the general formula [1] used in the present invention include N-hydroxymethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, and N-hydroxypropyl (meth) acrylamide. N-hydroxyisopropyl (meth) acrylamide, N-methylhydroxymethyl (meth) acrylamide, N-methylhydroxyethyl (meth) acrylamide, N-methylhydroxypropyl (meth) acrylamide, N-methylhydroxyisopropyl (meth) acrylamide, N-ethylhydroxymethyl (meth) acrylamide, N-ethylhydroxyethyl (meth) acrylamide, N-ethylhydroxypropyl (meth) acrylamide, N-ethylhydroxyisopropyl (meth) acryl Amide, N-propylhydroxymethyl (meth) acrylamide, N-propylhydroxyethyl (meth) acrylamide, N-propylhydroxypropyl (meth) acrylamide, N-propylhydroxyisopropyl (meth) acrylamide, N-isopropylhydroxyethyl (meth) Acrylamide, N-isopropylhydroxypropyl (meth) acrylamide, N-isopropylhydroxyisopropyl (meth) acrylamide, N, N-dihydroxymethyl (meth) acrylamide, N, N-dihydroxyethyl (meth) acrylamide, N, N-dihydroxypropyl (Meth) acrylamide, N, N-dihydroxyisopropyl (meth) acrylamide, N- [2- (3,4-dihydroxyphenyl) ethyl] acryl Amide, 4- (hydroxy) methacrylanilide, N- [1,1-bis (hydroxymethyl) ethyl] acrylamide, N- [1- (hydroxymethyl) propyl] methacrylamide, N- (2-hydroxyphenyl) methacrylamide N- (2-hydroxy-5-methylphenyl) acrylamide, 1- [4- (2-hydroxyethyl) -1-piperazinyl] -2-propen-1-one, 1-acryloyl-4-hydroxypiperidine. It is done. In particular, since N-hydroxyethyl (meth) acrylamide has a high refractive index (1.502), it can provide excellent transparency, and since skin irritation (PII = 0) is low, it is highly safe and easy to handle. Moreover, since a highly purified industrial product can be obtained easily, it is preferable. These monomers can be used alone or in combination of two or more.

The compound (B) having one or more isocyanate groups in one molecule used in the present invention is a monofunctional isocyanate having one isocyanate group in one molecule and two or more isocyanates in one molecule. The polyfunctional isocyanate which has group is mentioned, These can be used individually by 1 type or in combination of 2 or more types.

Examples of the compound having one isocyanate group in one molecule include monofunctional isocyanate compounds such as n-butyl isocyanate, isopropyl isocyanate, phenyl isocyanate, benzyl isocyanate, (meth) acryloyl isocyanate, and 2- (meth). (Meth) acryloyloxyalkyl such as acryloyloxyethyl isocyanate, 3- (meth) acryloyloxypropyl isocyanate, 2- (meth) acryloyloxy-1-methylethyl isocyanate, 2- (meth) acryloyloxy-2-methylethyl isocyanate Isocyanates. Specific examples of these product names include Karenz MOI and AOI (both manufactured by Showa Denko KK). These monofunctional isocyanates can be used singly or in combination of two or more.

As a polyfunctional isocyanate having two or more isocyanate groups in one molecule, for example,
Trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4 Aliphatic isocyanates such as 4-trimethylhexamethylene diisocyanate and 2,2,4-trimethylhexamethylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6- Aromatic isocyanates such as tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-diphenylmethane diisocyanate, xylylene diisocyanate Alicyclic isocyanates such as nates, cyclopentylene diisocyanate, cyclohexylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, methylcyclohexylene diisocyanate, 2,5-norbornane diisocyanate, 2,6-norbornane diisocyanate, Alternatively, multimers such as these adduct types, isocyanurate types, burette types and the like can be mentioned. Specific product names include trimethylolpropane / tolylene diisocyanate adduct type coronate L, trimethylolpropane / hexamethylene diisocyanate adduct type coronate HL, hexamethylene diisocyanate isocyanurate type coronate HX ( Examples thereof include Nippon Polyurethane Industry Co., Ltd.), Duranate 24A-100 (Asahi Kasei Kogyo Co., Ltd.), which is a biuret type of hexamethylene diisocyanate. These polyfunctional isocyanates can be used alone or in combination of two or more.

As the compound (B) having one or more isocyanate groups in one molecule, the polyfunctional isocyanate having two or more isocyanate groups in one molecule can be reacted with the isocyanate group in the molecule. An addition reaction product obtained by reacting with a compound having one or more active hydrogen-containing groups is exemplified.

The active hydrogen means a hydrogen atom in —OH, —COOH, —SH, —NH—, —NH 2, etc., and means a hydrogen atom having a reaction activity with the isocyanate group of the compound (B).

As a compound having one or more active hydrogen-containing groups capable of reacting with an isocyanate group in the molecule, a compound having one or more hydroxyl groups in one molecule, a compound having one or more carboxyl groups in one molecule, A compound having one or more thiol groups in one molecule or a compound having one or more amine groups in one molecule can be mentioned.

Examples of the compound having one or more hydroxyl groups in one molecule include methanol, ethanol, propanol, butanol, pentanol, hexanol, cyclohexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, and tetradecanol. , Alkanols such as pentadecanol, hexadecanol, heptadecanol, octadecanol, propylene glycol monomethyl ether, propylene glycol monopropyl ether, ethylene glycol monobutyl ether, polyethylene glycol monomethyl ether, polyethylene glycol monoethyl ether, polypropylene glycol Monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether, etc. Ether group-containing monools, ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, butanediol, polytetramethylene glycol, methylpropanepentanediol, methylpentanediol, hexanediol, neopentylglycol, 2-butyl-2-ethyl -1,3-propanediol, 2,2′-diethyl-1,3-propanediol, 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, 2-ethyl-1,3-hexanediol, 2,2 , 4-trimethyl-1,3-pentanediol, hydroxypivalic acid-neopentyl glycol ester, diols such as dimethylolpropanoic acid, dimethylolbutanoic acid, trimethylolethane, trimethylo Polyols such as propane, polytrimethylolpropane, trimethylolbutane, trimethyloloctane, glycerin, pentaerythritol, polypentaerythritol, polybutadienepolyol, hydrogenated polybutadienepolyol, polyethylene oxide, polypropylene oxide, ethylene oxide / propylene oxide block or Polyether polyol having at least one structure of random copolymerization, condensation of the polyol or polyether polyol with a polybasic acid such as maleic anhydride, fumaric acid, itaconic anhydride, itaconic acid, adipic acid, isophthalic acid Polyester polyols, caprolactone-modified polytetramethylene polyols, and other caprolactone-modified polyols, polyolefin polyols , Polycarbonate polyol, epoxy polyol and the like, and these can be used alone or in combination of two or more.

Examples of the compound having one or more carboxyl groups in one molecule include aliphatic unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, propiolic acid and crotonic acid, and aromatic unsaturated monocarboxylic acids such as cinnamic acid. Aliphatic unsaturated dicarboxylic acids such as acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid Such as aromatic dicarboxylic acid, monomethyl maleate, monoethyl maleate, monobutyl maleate, monohexyl maleate, monooctyl maleate, mono-2-ethylhexyl maleate and the like and corresponding fumaric acid monoester And saturated dicarboxylic acid monoesters. These can be used alone or in combination of two or more.

The compound having one or more thiol groups in one molecule is not particularly limited as long as it has an —SH group. For example, ethanethiol, mercaptocarboxylic acid, 2-aminoethanethiol, 2-mercaptoethanol, 2-mercaptoethanesulfonic acid, 1-propanethiol, 2-propene-1-thiol, 1-butanethiol, 1-pentanethiol, 1-hexanethiol, 1-heptanethiol, 1-octanethiol, 1-nonanethiol, 1-decanethiol, 1-undecanethiol, 1-dodecanethiol, 1-hexadecanethiol, 1-octadecanethiol, 2-propanethiol, 2-methyl-1-propanethiol, 2-methyl-2-propanethiol, 2- Butanethiol, 3-methyl-2-butanethio , T-dodecanethiol, 3-mercapto-2-butanol, 3-mercapto-1,2-propanediol, 2-mercaptopropionic acid, mercaptosuccinic acid, DL-homocysteine, thioacetic acid, 3-mercapto-2- Butanone, 3-mercapto-2-pentanone, methyl mercaptoacetate, ethyl mercaptoacetate, 2-ethylhexyl mercaptoacetate, isooctyl thioglycolate, 3-methoxybutyl mercaptoacetate, β-mercaptopropionic acid, methyl-3-mercaptopropio 2-ethylhexyl-3-mercaptopropionate, octyl-3-mercaptopropionate, methoxybutyl-3-mercaptopropionate, stearyl-3-mercaptopropionate, laurylthiop Lopionic acid, thioglycolic acid, methyl-3-mercaptopropionate, hexyl-3-mercaptopropionate, dodecyl-3-mercaptopropionate, tridecyl-3-mercaptopropionate, octadecyl-3-mercaptopropio 3-methoxybutyl-3-mercaptopropionate, cyclohexyl-3-mercaptopropionate, 2-mercaptoethyloctanoate, 2-furanmethanethiol, 2-phenylimidazole-4-carboxylic acid, 4,5 -Diphenyl-2-mercaptooxazole, 2-mercapto-2-thiazoline, 4-t-butyl-2-mercaptothiazole, 4,5-dimethyl-2-mercaptothiazole, 2-mercapto-4-methyl-5-thiazole acetic acid 1H-1,2,4- Riazole-3-thiol, 3-mercapto-4-methyl-4H-1,2,4-triazole, 4-amino-3-mercapto-4H-1,2,4-triazole, 4-amino-3-mercapto- 5-methyl-4H-1,2,4-triazole, 4-amino-3-mercapto-5- (trifluoromethyl) -4H-1,2,4-triazole, 4-amino-5-phenyl-4H- 1,2,4-triazole-3-thiol, 4-amino-3-mercapto-5- (methoxymethyl) -4H-1,2,4-triazole, 5- (4-pyridyl) -1,3,4 -Oxadiazol-2-thiol, 1-methyl-1,2,3,4-tetrazole-5-thiol, 1- {2- (dimethylamino) ethyl} -1H-tetrazol-5-thiol, 5-mer Put-1-phenyltetrazole, 1- (3,4-dichlorophenyl) -5-mercapto-1H-tetrazole, 1- (m-acetamidophenyl) -5-mercapto-1H-tetrazole, 1- (p-hydroxy Phenyl) -5-mercapto-1H-tetrazole, 5-mercapto-1- (p-methoxyphenyl) -1H-tetrazole, 1- (p-carbamoylphenyl) -5-mercapto-1H-tetrazole, 1- (p- Carboxyphenyl) -5-mercapto-1H-tetrazole, cyclohexanethiol, 8-mercaptomentone mixture, thiophenol, thiobenzoic acid, o-fluorobenzenethiol, m-fluorobenzenethiol, p-fluorobenzenethiol, o-chloro Thiophenol, m-chlorothi Ophenol, o-bromobenzenethiol, m-bromobenzenethiol, p-bromobenzenethiol, m-hydroxybenzenethiol, p-mercaptophenol, o-methoxythiophenol, m-methoxythiophenol, p-methoxythiophenol, 1,2-benzenedithiol, p-nitrobenzenethiol, 2-aminothiophenol, m-aminothiophenol, p-aminothiophenol, p- (trifluoromethyl) benzenethiol, o-methylbenzenethiol, m-methylbenzene Thiol, o-isopropylbenzenethiol, p-isopropylbenzenethiol, pt-butylthiophenol, thiosalicylic acid, p-mercaptobenzoic acid, methylthiosalicylate, p-mer Ptophenylacetic acid, p- (trimethylsilyl) benzenethiol, 2,4-dichlorobenzenethiol, 2,6-dichlorobenzenethiol, 2-amino-4-chlorobenzenethiol, 5-fluoro-2-mercaptobenzoic acid, 2,3 -Dimethylbenzenethiol, 2,4-dimethylbenzenethiol, 2,5-dimethylbenzenethiol, 2,6-dimethylthiophenol, 2,5-dimethoxythiophenol, 3,5-bis (trifluoromethyl) benzenethiol, 2,4,5-trichlorobenzenethiol, pentachlorothiophenol, p-chlorophenylmethanethiol, p-fluorobenzenemethanethiol, o-methyl-α-toluenethiol, m-methyl-α-toluenethiol, (p-methyl) Phenyl) Tanthiol, 4-methoxy-α-toluenethiol, p- (trimethylsilyl) phenylmethanethiol, 1,2-benzenedimethanethiol, 1,3-benzenedimethanethiol, 1,4-benzenedimethanethiol, 2,4 -Bis (mercaptomethyl) -1,3,5-trimethylbenzene, triphenylmethanethiol, 2-mercaptopyridine, 4-mercaptopyridine, 2-mercapto-5- (trifluoromethyl) pyridine, 2-mercapto-5 Nitropyridine, thionicotinic acid, 2-mercaptopyridine-N-oxide, 2-mercaptopyrimidine, 2-thiouracil, 6-methyl-2-thiouracil, 4,6-diamino-2-mercaptopyrimidine, 4,6-dimethyl-2 -Mercaptopyrimidine, 4,5-diamino-6 -Hydroxy-2-mercaptopyrimidine, trithiocyanuric acid, 2-mercaptobenzimidazole, 2-mercapto-5-methylbenzimidazole, 5-methoxy-2-benzimidazolethiol, 5- (difluoromethoxy) -2-mercapto-1H- Monofunctional thiol compounds such as benzimidazole, 2-benzoxazolethiol, 6-thioguanine, 1-naphthalenethiol, 2-naphthalenethiol, 2-naphthalenemethanethiol, 1,3-propanedithiol, 1,4-butanedithiol, 1 , 5-pentanedithiol, 1,6-hexanedithiol, 1,10-decanedithiol, 2,3-butanedithiol, 2,3-dimercapto-1-propanol, ethylene glycol bis (mercaptoacetate), 1,4 Butanediol bis (mercaptoacetate), trimethylolpropane tris (3-mercaptopropionate), trimethylolpropane tris (mercaptoacetate), tris-{(3-mercaptopropionyloxy) -ethyl} -isocyanurate, pentaerythritol tetrakis (Mercaptoacetate), pentaerythritol tetrakis (3-mercaptopropionate), tetraethylene glycol bis (3-mercaptopropionate), dipentaerythritol hexakis (3-mercaptopropionate), 2- {2,4 , 6-Trioxo-3,5-bis [2- (3-sulfanylpropanoyloxy) ethyl] -1,3,5-triazinan-1-yl} ethyl-3-sulfanylpropionate, 3,3′- H Dipropionic acid, 3,3′-thiodipropionic acid dimethyl, dithiodipropionic acid, ethylene glycol bis (3-mercaptopropionate), 1,4-butanediol bis (3-mercaptopropionate), tetraethylene Glycol bis (3-mercaptopropionate), trimethylolethane tris (3-mercaptopropionate), 4-imidazole dithiocarboxylic acid, 2-methylimidazole-4-dithiocarboxylic acid, 4-methylimidazole-5-di Thiocarboxylic acid, 5-methyl-1,3,4-thiadiazole-2-thiol, 2-mercapto-5-methylthio-1,3,4-thiadiazole, 5-mercapto-3- (methylthio) -1,2,4 -Thiadiazole, 2,5-dimercapto-1,3,4-thiadiazole 2-amino-5-mercapto-1,3,4-thiadiazole, 2- (5-mercapto-1,3,4-thiadiazol-2-ylthio) propionic acid, 3- (5-mercapto-1,3,4) -Thiadiazol-2-ylthio) propionic acid, 2- (5-mercapto-1,3,4-thiadiazol-2-ylthio) succinic acid, 2- (N-carboxymethyl-N-phenyl) amino-4,6- Dimercapto-1,3,5-triazine, 6- (dibutylamino) -1,3,5-triazine-2,4-dithiol, tris {2- (3-mercaptopropionyloxy) ethyl} isocyanurate, 2- Mercaptobenzothiazole, 5-chloro-2-mercaptobenzothiazole, 6-amino-2-mercaptobenzothiazole, 6-nitro-2-mer Hept benzothiazole include multifunctional thiols such as 2,6-di-mercaptopurine. These can be used alone or in combination of two or more.

The compound having one or more amine groups in one molecule is preferably a primary amine compound or a secondary amine compound, and more preferably a primary amine compound. The amine compound may have a hydroxyl group.

Examples of the primary amine compound include ethylamine, n-propylamine, isopropylamine, n-butylamine, sec-butylamine, tert-butylamine, n-pentylamine, 1-methylbutylamine, 1-ethylpropylamine, 2- Ethylbutylamine, hexylamine, n-octylamine, 2-ethylhexylamine, decylamine, stearylamine, cyclohexylamine, ethanolamine, 6-aminohexanol, p-methoxybenzylamine, methoxypropylamine, 3,4-dimethoxyphenylethylamine, 2,5-dimethoxyaniline, furfurylamine, tetrahydrofurfurylamine, benzylamine, aniline, hexamethylenediamine and the like can be mentioned. These are used alone or in combination of two or more. It can be used in conjunction look.

Examples of the secondary amine compound include diethylamine, dipropylamine, di-n-butylamine, di-sec-butylamine, di-tert-butylamine, diisopropylamine, diisobutylamine, dipentylamine, di-n-octylamine, Di-2-ethylhexylamine, didecylamine, distearylamine, N-ethyl-1,2-dimethylpropylamine, N-methylbutylamine, N-butylethylamine, diethanolamine, diisopropanolamine, 2- (methylamino) ethanol, 2 -(Isopropylamino) ethanol, 2- (ethylamino) ethanol, piperidine, hexamethyleneimine, morpholine and the like can be mentioned, and these can be used alone or in combination of two or more.

In obtaining the compound (B) having one or more isocyanate groups in one molecule, in particular, the active hydrogen-containing group of the compound having one or more active hydrogen-containing groups capable of reacting with an isocyanate group in the molecule. It is preferable to carry out the reaction so that the total of the isocyanate groups of the polyfunctional isocyanate having two or more isocyanate groups in one molecule is equal to or greater than the total, and among them, the equivalent ratio (active hydrogen-containing group / isocyanate group) ) Is preferably reacted at a ratio of 1 / 1.05 to 1/2.

The urethane (meth) acrylamide of the present invention comprises two compounds in one molecule and one compound having one or more active hydrogen-containing groups capable of reacting with the isocyanate group from the viewpoint of stability of reaction control and shortening of production time. After reacting the polyfunctional isocyanate having the above isocyanate group to obtain a compound (B) having one or more isocyanate groups in one molecule, the isocyanate group of the isocyanate group-containing compound (B) is It is obtained by forming a urethane bond with the hydroxyl group of the compound (A) represented by the general formula [1].

The reaction of the compound having one or more active hydrogen-containing groups capable of reacting with an isocyanate group in the molecule and the polyfunctional isocyanate having two or more isocyanate groups in one molecule is performed by mixing both The temperature can be increased by a known method. This reaction is desirably performed at a temperature of 5 to 100 ° C, preferably 20 to 80 ° C. The reaction components can be mixed by a known method. Moreover, the addition of the reaction components can be carried out in several stages as desired. Moreover, although the said reaction is possible even without a solvent, it can be implemented in an organic solvent or a reactive diluent as needed. Examples of the solvent that can be used include acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, ethyl acetate, butyl acetate, tetrahydrofuran, hexane, cyclohexane, benzene, toluene, xylene, and aliphatic hydrocarbon solvents ( For example, petroleum ether). The reactive diluent that can be used is not particularly limited as long as it does not react with isocyanate, but methyl acrylate, butyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, long-chain aliphatic acrylate, allyl acrylate, cyclohexyl acrylate 1,6-hexane diacrylate, tetraethylene glycol diacrylate, dipentaerythritol hexaacrylate, trimethylolpropane triacrylate, isobornyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dimethylacrylamide, diethylacrylamide, N-acryloyl Examples include morpholine. The usage-amount of an organic solvent or a reactive diluent is 0 to 200 weight% with respect to the hydroxyl-containing (meth) acrylamide represented by General formula [1], Preferably it is 0 to 100 weight%.

In such a reaction, a catalyst can be added for the purpose of promoting the reaction. Examples of the catalyst include potassium or sodium salts of alkylphosphonic acids; metal salts of fatty acids having 8 to 20 carbon atoms such as sodium, potassium, nickel, cobalt, cadmium, barium, calcium, zinc; dibutyltin dilaurate, dioctyl Organic tin compounds such as tin maleate, dibutyldibutoxytin, bis (2-ethylhexyl) tin oxide, 1,1,3,3-tetrabutyl-1,3-diacetoxydistanoxane, which may be used alone or Two or more types can be used in combination. The amount of the catalyst used is usually 0.01 to 5% by weight relative to the total weight of the compound (A) represented by the general formula [1] and the compound (B) having one or more isocyanate groups in one molecule. %, Preferably 0.1 to 3% by weight.

Moreover, in order to suppress radical polymerization of the polymerizable unsaturated double bond of the compound (A) represented by the general formula [1], a radical polymerization inhibitor can be used as necessary. Examples of the radical polymerization inhibitor include quinone polymerization inhibitors such as hydroquinone, methoxyhydroquinone, benzoquinone, and p-tert-butylcatechol; 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, Alkylphenol polymerization inhibitors such as 2-tert-butyl 4,6-dimethylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,4,6-tri-tert-butylphenol; alkylated diphenylamine; Amine polymerization inhibitors such as N, N'-diphenyl-p-phenylenediamine and phenothiazine; N-oxyls such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl; dimethyldithiocarbamic acid Copper, copper diethyldithiocarbamate, dibuty Copper dithiocarbamate-based polymerization inhibitors such as copper dithiocarbamate and the like. These may be used alone or in combination of two or more thereof.

The addition amount of these polymerization inhibitors may be appropriately set according to the type and blending amount of the compound (A) represented by the general formula [1]. From the viewpoint of property and economy, it is usually 0.001 to the total weight of the compound (A) represented by the general formula [1] and the compound (B) having one or more isocyanate groups in one molecule. It is preferably 5% by weight, and more preferably 0.01 to 1% by weight.

The weight average molecular weight of the urethane (meth) acrylamide of the present invention is preferably a monomer or oligomer of 200 to 4,000, or a polymer of 4,000 to 200,000, and more preferably 1,000 to It is preferable that it is 10,000. When the weight average molecular weight is less than 200, the tackiness is low, and when it exceeds 200,000, the coating property is deteriorated.

The adhesive for polarizing plate containing urethane (meth) acrylamide of the present invention may further contain an acrylic monomer (C) containing a hydroxyl group and / or an acrylic monomer (D) containing an epoxy group. It is preferable in terms of adhesive properties and coatability.

Examples of the acrylic monomer (C) containing a hydroxyl group include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, etc. in addition to the compound (A) represented by the general formula [1]. Diol compounds such as hydroxyalkyl (meth) acrylates having 2 to 8 carbon atoms, hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, ethylene glycol, 1,6-hexanediol, neopentyl glycol, polyethylene glycol, polypropylene glycol, and polybutylene glycol; Hydroxyl group-containing (meth) acrylate and glycidyl (meth) acrylate obtained by partial esterification reaction with (meth) acrylic acid, acetic acid, propionic acid, p-tert-butylbenzoic acid, fat Acid etc., or a hydroxyl group-containing (meth) obtained by reacting a monoamine such as an alkyl amine acrylate, and the like. These monomers may be used alone or in combination of two or more. Among these, hydroxyalkyl (meth) acrylates having an alkyl group of 2 to 8 are preferable from the viewpoint of adhesiveness and solubility with the urethane (meth) acrylamide of the present invention.

Examples of the acrylic monomer (D) containing an epoxy group include glycidyl (meth) acrylate.

About content of the acrylic monomer (C) containing urethane (meth) acrylamide and a hydroxyl group in the adhesive agent for polarizing plates of this invention, urethane (meth) acrylamide / (C) is 10-60 / 40-90 (weight). Ratio), more preferably 15 to 50/50 to 85 (weight ratio). Moreover, about content of the acrylic monomer (D) containing urethane (meth) acrylamide and an epoxy group in the adhesive agent for polarizing plates of this invention, urethane (meth) acrylamide / (D) is 30-95 / 5. It is preferably 70 (weight ratio), more preferably 40 to 80/10 to 60 (weight ratio). If the content of the acrylic monomer (C) having a hydroxyl group and / or the acrylic monomer (D) having an epoxy group is less than the above lower limit value, it may not be possible to provide an additional function by addition, and the above upper limit value. Exceeding the range is not preferred because the curability and adhesive strength of the adhesive may be reduced, or the adhesive strength, transparency, heat resistance, durability and the like may not be sufficiently obtained.

In the adhesive for polarizing plates of the present invention, it is preferable from the viewpoint of heat resistance and adhesion to the substrate that monofunctional (meth) acrylamide and / or monofunctional (meth) acrylate is further added. Examples of the monofunctional (meth) acrylamide used in the present invention include N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N -Methoxyethyl (meth) acrylamide, N-ethoxyethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide, N-isobutoxymethyl (meth) acrylamide, N-vinylpyrrolidone, N-vinylcaprolactam, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-acryloylmorpholine and the like can be mentioned. Moreover, these monomers may be used independently and may be used together 2 or more types. Among these, N, N-dimethylacrylamide, N, N-diethylacrylamide, N-acryloylmorpholine, Nn-butoxymethylacrylamide, and N-isobutoxymethylacrylamide have strong permeability and adhesion to protective films and the like. Is particularly preferred.

Examples of the monofunctional (meth) acrylate used in the present invention include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) ) Acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, tridecyl (meth) acrylate, Methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, propoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate Rate, methoxytriethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, phenoxyhexaethylene glycol (meth) Acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, tert-butylcyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, dicyclo Pentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, borne (Meth) acrylate, isobornyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, allyl (meth) acrylate. These monomers may be used alone or in combination of two or more.

The total amount of monofunctional (meth) acrylamide and / or monofunctional (meth) acrylate in the polarizing plate adhesive of the present invention is 1 to 40% by weight, and 5 to 30% by weight is particularly preferable. When the content is less than 1% by weight, the permeability and wettability to the protective film, retardation film, and optical compensation film cannot be sufficiently provided, the adhesion is insufficient, and the adhesive strength of the polarizing plate obtained as a laminate is lowered. It becomes easy to peel from the protective film interface. On the other hand, when it exceeds 40% by weight, the wettability with respect to the PVA polarizing film is lowered, and sufficient adhesive strength cannot be obtained, and the transparency, heat resistance, durability and the like intended by the present invention cannot be sufficiently obtained. there is a possibility.

In the polarizing plate adhesive of the present invention, various active ingredients can be further blended as necessary. In that case, other active ingredients are added so that the total blending amount of the acrylic monomer (C) containing urethane (meth) acrylamide and the hydroxyl group and / or the acrylic monomer containing epoxy group (D) is 40% by weight or more. Blend. When the amount is less than 40% by weight, the high adhesive strength, transparency, heat resistance, durability, and the like that are the object of the present invention may not be sufficiently obtained.

The adhesive for polarizing plates of the present invention can further contain a polymerizable tertiary amine compound. The polymerizable tertiary amine compound is a dialkylamino (meth) acrylamide monomer and a dialkylamino (meth) acrylate monomer represented by the general formula [2].

In the general formula [2], R ₄ is a hydrogen atom or a methyl group, R ₅ and R ₆ are each independently an alkyl group having 1 to 3 carbon atoms, which may be the same or different, and Y Represents an oxygen atom or NH-, and Z represents an alkylene group having 1 to 3 carbon atoms.

Examples of the dialkylaminoalkyl (meth) acrylamide include dimethylaminoethyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, diethylaminopropyl (meth) acrylamide, and methylethylaminoethyl (meth). Examples include acrylamide, methylpropylaminoethyl (meth) acrylamide, methylethylaminopropyl (meth) acrylamide, methylpropylaminopropyl (meth) acrylamide, and dipropylaminopropyl (meth) acrylamide.

Examples of the dialkylaminoalkyl (meth) acrylate include dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate, and methylethylaminoethyl (meth). Examples include acrylate, methylpropylaminoethyl (meth) acrylate, methylethylaminopropyl (meth) acrylate, methylpropylaminopropyl (meth) acrylate, and dipropylaminopropyl (meth) acrylate.

The polymerizable tertiary amine compound is a protective film, for example, a retardation film used for the purpose of improving response speed, brightness, contrast, viewing angle, etc., a liquid crystalline compound for large liquid crystal displays and 3D displays. It is excellent in wettability with respect to a coated optical compensation film, an obliquely stretched optical compensation film, etc., and by adhering these, the adhesiveness between the adhesive and the protective film is further improved, and an effect of improving adhesive strength can be imparted.

The compounding amount of these polymerizable tertiary amine compounds is not particularly limited. In general, it is preferably added in an amount of 0.01 to 50% by weight, particularly 0.1 to 30% by weight, based on urethane (meth) acrylamide which is the main component of the adhesive of the present invention. When the compounding amount of the polymerizable tertiary amine compound is less than 0.01% by weight, there is a possibility that the additional function due to the above addition cannot be provided. When the compounding amount exceeds 50% by weight, the polymerizable tertiary amine compound is not provided. Depending on the varieties, the adhesive may turn yellow over time.

An organic ionic compound can be further blended in the polarizing plate adhesive of the present invention. Examples of the organic ionic compound include ionic vinyl monomers and / or oligomers and polymers containing them as constituent components. The ionic vinyl monomer is an onium salt obtained by combining a cation and an anion. Specifically, the cation is a (meth) acrylate-based or (meth) acrylamide-based ammonium ion or imidazolium ion, the anion is Cl ⁻ , Hal ion such as Br ⁻ and I ⁻ or OH ⁻ , CH ₃ COO ⁻ , NO ₃ ⁻ , ClO ₄ ⁻ , PF ₆ ⁻ , BF ₄ ⁻ , HSO ₄ ⁻ , CH ₃ SO ₃ ⁻ , CF ₃ SO ₃ ⁻ , Examples include inorganic acid anions or organic acid anions such as CH ₃ C ₆ H ₆ SO ₃ ⁻ , C ₄ F ₉ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , and SCN ⁻ .

As a method for synthesizing the ionic vinyl monomer used in the present invention, generally, a tertiary amine having a polymerizable group is converted to a quaternizing agent such as an alkyl halide, dialkyl sulfates, or methyl p-toluenesulfonate. The quaternary ammonium salt obtained by quaternization is further subjected to anion exchange using a salt having the target anion, or the quaternary ammonium salt is converted to water using an anion exchange resin. There is a method of neutralizing with an acid having a target anion after conversion to an oxide, and the like. JP, 2011-140448, 2011-140455, 2011-153109) can be referred to.

The ions of the organic ionic compound easily form hydrogen bonds or ionic bonds with the hydroxyl groups on the surface of the PVA polarizing film, and can impart conductivity and antistatic properties. The inventors presume that the wettability of the polarizing layer to the protective film is improved, it can be applied more uniformly, and a film can be formed more stably. Furthermore, since the ionic vinyl monomer itself is an active energy ray-curable compound, it is permanently conductive without being bleeded out by copolymerizing with the main component of the active energy ray-curable polarizing plate adhesive of the present invention. And an auxiliary effect of imparting antistatic properties and an effect of improving adhesion to a polarizing film, a protective film and the like.

The organic ionic compound used in the present invention is one kind selected from a monomolecular compound having a molecular weight of several tens to several hundreds, an oligomer having a molecular weight of several hundreds to several thousand, and a polymer having a molecular weight of several thousand to tens of thousands, or as necessary. Two or more kinds can be used in combination. Since the compounding quantity of these organic ionic compounds can be adjusted with the number of functional groups and molecular weight of an ion pair, there is no restriction | limiting in particular. In general, it is preferably added in an amount of 0.01 to 50% by weight, particularly 0.1 to 20% by weight, based on urethane (meth) acrylamide, which is the main component of the adhesive of the present invention. If the blending amount of the organic ionic compound is less than 0.01% by weight, there is a possibility that the additional function by the addition described above may not be provided. However, the transparency of the adhesive may be reduced.

In the present invention, a bifunctional or higher curable component can be further used in the polarizing plate adhesive. As the bifunctional or higher curable component, polyfunctional (meth) acrylate, polyfunctional (meth) acrylamide, polyfunctional epoxy compound, and polyfunctional epoxy (meth) acrylate are preferable. Polyfunctional epoxy (meth) acrylate is obtained by reaction of a polyfunctional epoxy compound and (meth) acrylic acid.

Examples of the polyfunctional (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, ditetraethylene glycol di (Meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polytetramethylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (Meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,7-heptanediol di (meth) acrylate, 1,8- Kutandiol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate , Ethylene oxide-modified phosphoric acid di (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol Tetra (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, tricyclodecane dimethano Rudi (meth) acrylate, ethylene oxide modified bisphenol A di (meth) acrylate, propylene oxide modified bisphenol A di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, acrylate ester (dioxane glycol diacrylate), alkoxylated hexanediol Examples thereof include monomers and oligomers such as di (meth) acrylate, alkoxylated cyclohexanedimethanol di (meth) acrylate, epoxy (meth) acrylate, and urethane (meth) acrylate. Among these, 1,6-hexanediol diacrylate, dicyclopentenyl diacrylate, acrylate ester (dioxane glycol diacrylate), and ethylene oxide-modified bisphenol A diacrylate are adhesive to the base material, water resistance, adhesive composition It is particularly preferred from the viewpoint of compatibility.

Examples of the polyfunctional (meth) acrylamide include methylenebis (meth) acrylamide, ethylenebis (meth) acrylamide, diallyl (meth) acrylamide and the like.

Examples of the polyfunctional epoxy compound include aromatic epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins.
Contains a polyfunctional epoxy compound and / or a linear compound having two or more epoxy groups at the terminal or side chain of bifunctional or higher and / or a branched compound having two or more epoxy groups at the terminal or side chain be able to. Examples of the epoxy compound include various types, and examples thereof include aromatic epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins.

Examples of the aromatic epoxy resin include bisphenol type diglycidyl ether, bisphenol F diglycidyl ether, bisphenol type epoxy resin such as bisphenol S diglycidyl ether, phenol novolac epoxy resin, cresol novolac epoxy resin, Examples thereof include novolak-type epoxy resins such as hydroxybenzaldehyde phenol novolac epoxy resins, glycidyl ethers of tetrahydroxyphenylmethane, glycidyl ethers of tetrahydroxybenzophenone, and polyfunctional epoxy resins such as epoxidized polyvinylphenol.

Examples of the alicyclic epoxy resin include hydrogenated aromatic epoxy resins, cyclohexane-based, cyclohexylmethyl ester-based, cyclocyclohexylmethyl ether-based, spiro-based, and tricyclodecane-based epoxy resins.

Examples of the aliphatic epoxy resin include polyglycidyl ethers of aliphatic polyhydric alcohols or alkylene oxide adducts thereof. Examples include 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, propylene. Polyethers of polyether polyols obtained by adding one or more alkylene oxides (ethylene oxide or propylene oxide) to aliphatic polyhydric alcohols such as glycol diglycidyl ether, ethylene glycol, propylene glycol, and glycerin A glycidyl ether etc. are mentioned.

Examples of the polyfunctional epoxy (meth) acrylate include aromatic epoxy resins, alicyclic epoxy resins, and epoxy (meth) acrylates of aliphatic epoxy resins.

These polyfunctional (meth) acrylates, polyfunctional (meth) acrylamides, polyfunctional epoxy compounds and polyfunctional epoxy (meth) acrylates may be used alone or in combination of two or more. Good.

In the present invention, the polarizing plate adhesive may further contain a linear and / or branched oligomer or polymer having a skeleton such as acrylic, ester, ether, urethane, or amide. Specifically, An oligomer composed of the above-mentioned polyfunctional (meth) acrylate and / or polyfunctional (meth) acrylamide having a weight average molecular weight of less than 10,000, and / or a curable resin having a weight average molecular weight of 10,000 or more. Can be mentioned.

Examples of the curable resin having a weight average molecular weight of 10,000 or more include bifunctional polyurethane (meth) acrylate, polyfunctional polyurethane (meth) acrylate, bifunctional polyester (meth) acrylate, and polyfunctional urethane (meth). Acrylate, bifunctional polyester (meth) acrylate, polyfunctional polyester (meth) acrylate, bifunctional polyether (meth) acrylate, polyfunctional polyether (meth) acrylate, bifunctional polyamide (meth) acrylate, polyfunctional polyamide (meth) Acrylate, Bifunctional poly (meth) acrylate (meth) acrylate, Multifunctional poly (meth) acrylate (meth) acrylate, Bifunctional poly (meth) acrylate (meth) acrylamide, Multifunctional poly (meth) acrylic Ester (meth) acrylamide, bifunctional poly (meth) acrylamide (meth) acrylate, polyfunctional poly (meth) acrylamide (meth) acrylate, bifunctional polystyrene (meth) acrylate, polyfunctional polystyrene (meth) acrylate, bifunctional polyacrylonitrile (Meth) acrylate, polyfunctional polyacrylonitrile (meth) acrylate, bifunctional epoxy acrylate (bisphenol A type), polyfunctional epoxy acrylate (bisphenol A type) and the like. Moreover, these polymers may be used individually by 1 type, and may be used in combination of 2 or more type.

It is preferable that the total compounding quantity of the polymerizable polyfunctional compound of the said paragraph numbers 0056-0066 in the adhesive composition for polarizing plates of this invention is 1 to 40 weight%. The polymerizable polyfunctional compound has an effect of appropriately adjusting the crosslinking density of the adhesive and an effect of improving water resistance, and can also provide a specific function depending on the molecular weight and the number of double bonds in the molecule. For example, when a polyfunctional monomer or oligomer is used, it is preferable to add 1% by weight or more because it has an effect of improving the strength, heat resistance, water resistance and durability of the adhesive. On the other hand, if the blending amount exceeds 40% by weight, the crosslinking rate is increased, so that the hardness of the adhesive layer is improved, but the elasticity is lost and it is easily broken.

In addition, the polyfunctional polymer can impart an anchor coating effect and a curing shrinkage suppressing effect, improve the wettability and adhesion to a protective film, a retardation film, an optical compensation film, etc., and the hardness of the adhesive layer after curing. There is an effect of adjusting the balance of elastic force. If the blending amount is less than 1% by weight, the above-mentioned effect of addition may not be sufficiently obtained. On the other hand, if the blending amount exceeds 40% by weight, the viscosity of the adhesive composition is remarkably increased. There is a risk that it cannot be applied smoothly.

In the adhesive for polarizing plates of the present invention, other polymerizable compounds can be added for adjusting the viscosity. Examples include unsaturated nitrile monomers, unsaturated carboxylic acids, amide group-containing monomers, methylol group-containing monomers, alkoxymethyl group-containing monomers, vinyl esters, radical polymerization compounds having reactive double bonds in the molecular chain such as olefins. .

Examples of the unsaturated nitrile monomer include acrylonitrile and methacrylonitrile.

Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, monoalkyl itaconate and the like.

The polymerizable compound is not limited to one type, and a plurality of types may be used in combination. Moreover, when using such a polymeric compound, it is preferable to make it contain 1 to 50weight% with respect to urethane (meth) acrylamide which is a main structural component of the adhesive agent of this invention, and contains 5 to 30weight% It is particularly preferred that If the content is less than 1% by weight, the effect of addition is not recognized, and if it exceeds 50% by weight, there is a problem that the strength of the adhesive cannot be sufficiently obtained.

By using the adhesive for polarizing plates of the present invention, a polarizing film and a polarizing layer protecting and / or retardation film, or an optical compensation film are bonded together and cured by irradiating with active energy rays, whereby an optical laminated film such as a polarizing plate is obtained. Can be produced. The glass transition temperature of the adhesive layer formed thereby is preferably 20 ° C. or higher and 200 ° C. or lower, and more preferably 30 ° C. or higher and 180 ° C. or lower. If the glass transition temperature of the adhesive layer is less than 20 ° C, the heat resistance and durability of the produced polarizing plate may not be sufficiently satisfied. If the glass transition temperature exceeds 200 ° C, the elasticity of the adhesive layer will rapidly increase. There exists a fault which falls and a polarizing plate becomes easy to break.

The active energy ray of the present invention is defined as an energy ray capable of decomposing a compound (photopolymerization initiator) that generates active species to generate active species. Examples of such active energy rays include light energy rays such as visible light, ultraviolet rays (UV), electron beams (EB), infrared rays, X rays, α rays, β rays, and γ rays. However, it is preferable to use ultraviolet rays because it has a certain energy level, has a high curing rate, is relatively inexpensive, and is compact.

When the polarizing plate adhesive of the present invention is cured, a photopolymerization initiator is added. The photopolymerization initiator is not particularly required when an electron beam is used as the active energy ray, but is required when ultraviolet rays are used. There is no restriction | limiting in particular as a photoinitiator, A photoradical polymerization initiator and / or a photocationic polymerization initiator are used.

As the radical photopolymerization initiator, for example, acetophenones, benzophenones, α-hydroxy ketones, benzyl methyl ketals, α-amino ketones, bisacylphosphine oxides and the like are used alone or in combination. Specific examples include Irgacure 184, Irgacure 651, Darocur 1173, Irgacure 907, Irgacure 369, Irgacure 819, and Lucirin TPO manufactured by Ciba Specialty Chemicals.

The photocationic polymerization initiator is not particularly limited as long as it generates a cationic polymerization catalyst such as Lewis acid by ultraviolet irradiation. For example, an onium salt such as a diazonium salt, an iodonium salt, or a sulfonium salt is used. it can. Specifically, aryldiazonium hexafluoroantimonate, aryldiazonium hexafluorophosphate, aryldiazonium tetrafluoroborate, diaryliodonium hexafluoroantimonate, diaryliodonium hexafluorophosphate, diaryliodonium tetrafluoroborate, triarylsulfonium hexa Examples include fluoroantimonate, triarylsulfonium hexafluorophosphate, and triarylsulfonium tetrafluoroborate. Commercially available cationic photopolymerization initiators include Union Carbide UVI-6990, Dow Chemical Japan UVI-6992, Daicel UCB Uvacure 1591, Asahi Denka Co., Ltd. Adekaoptomer SP-150, Adekaopter Mer-SP-170, DPI-101, DPI-105, MPI-103, MPI-105, BBI-101, BBI-103, BBI-105, TPS-102, TPS-103, TPS-105 manufactured by Midori Chemical Co., Ltd. MDS-103, MDS-105, DTS-102, DTS-103, Irgacure 250 manufactured by Ciba Specialty Chemicals, and the like. These photopolymerization initiators may be used alone or in combination of two or more.

The amount of these photopolymerization initiators is not particularly limited, but is generally 0.1 to 10% by weight, particularly 0.5 to 5% by weight, based on the active energy ray-curable adhesive composition or adhesive. Is preferably added. If it is less than 0.1% by weight, sufficient curability cannot be obtained, and if it exceeds 10% by weight, the adhesive strength may be lowered or the adhesive layer may be yellowed.

The polarizing plate adhesive of the present invention originally does not need to contain water or an organic solvent, but for the purpose of adjusting the viscosity of the adhesive and further improving the wettability and formability of the formed adhesive layer. Water or an organic solvent may be added. When an organic solvent is used, toluene, tetrahydrofuran, N-methylpyrrolidone, N-methylformamide, N, N-dimethylformamide, dimethylacetamide and the like can be mentioned. When adding water or an organic solvent, apply an adhesive on the protective film, retardation film, or optical compensation film, then remove the water or organic solvent by heating, and bond with a PVA polarizing film to irradiate active energy rays. Just do it.

In the range that does not hinder the properties of the adhesive, transparency, durability, moisture resistance, etc. of the molded product such as an optical film such as a polarizing plate and a polarizing plate produced therefrom, and a sheet, a surfactant, You may use together other arbitrary components, such as an antiblocking agent, a leveling agent, a dispersing agent, an antifoamer, antioxidant, a ultraviolet sensitizer, and an antiseptic | preservative.

The PVA polarizing film used in the present invention is usually obtained by dyeing and adsorbing a dichroic material such as iodine or an organic dye on a polyvinyl alcohol resin film and uniaxially stretching the dichroic material. The polyvinyl alcohol resin is usually obtained by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate, but is not necessarily limited to this in the present invention, and a small amount of unsaturated carboxylic acid (salt, ester, amide). And olefins (including nitriles), olefins having 2 to 30 carbon atoms (ethylene, propylene, n-butene, isobutene, etc.), vinyl ethers, unsaturated sulfonates, and the like, which are copolymerizable with vinyl acetate. A modified polyvinyl alcohol resin may be used. The weight average molecular weight of the polyvinyl alcohol resin is not particularly limited, but is preferably 60,000 to 300,000, more preferably 120,000 to 260,000, and the saponification degree is 80 mol% or more. In particular, 85 to 100 mol%, more preferably 98 to 100 mol%. Although the thickness of these polarizing films is suitably determined according to the use for which the polarizing plate is used, it is generally about 5 to 80 μm.

The polarizing layer protective film used in the present invention is not particularly limited as long as its transparency, mechanical strength, thermal stability, isotropy, and the like are good. For example, a thermoplastic resin Can be used. Specific examples of these thermoplastic resins include (meth) acrylic resins, cyclic polyolefin resins, cellulose resins, polyester resins, polysulfonic acid resins, polyacrylic resins such as polymethyl methacrylate, acrylonitrile and styrene copolymers, and the like. Examples thereof include resins, polycarbonate resins, polyamide resins, and polyimide resins. These thermoplastic resins may be used alone or in combination of two or more.

Examples of the (meth) acrylic resin include poly (meth) acrylic acid esters such as polymethyl methacrylate, methyl methacrylate- (meth) acrylic acid ester copolymers, and the like. Examples of commercially available products include “Acripet VH”, “Acrypet VRL20A” manufactured by Mitsubishi Rayon Co., Ltd., “Sanduren” manufactured by Kaneka Corporation, and the like.

The cyclic polyolefin resin is a general term for resins that are polymerized using a cyclic olefin as a polymerization unit, and a cyclic olefin ring-opening (co) polymer, a cyclic olefin addition polymer, a cyclic olefin and an α such as ethylene and propylene. -Olefin and its copolymer (typically random copolymer), the graft polymer which modified these with unsaturated carboxylic acid or its derivative (s), those hydrides, etc. are mentioned. Specific examples of the cyclic olefin include norbornene monomers. Examples of commercially available products include trade names “ZEONEX” and “ZEONOR” manufactured by ZEON CORPORATION, product names “ARTON” manufactured by JSR Corporation, “TOPAS” manufactured by TICONA Corporation, and products manufactured by Mitsui Chemicals, Inc. "APEL" etc. are mentioned.

The cellulose resin is a general term for esters of cellulose and fatty acids, and examples thereof include cellulose triacetate (also called triacetyl cellulose), cellulose diacetate, cellulose tripropionate, and cellulose dipropionate. Examples of commercially available cellulose triacetate include Fuji Photo Film Co., Ltd .; trade names “UV-50”, “UV-80”, “SH-80”, “TD-80U”, and the like.

The retardation film used in the present invention is a transparent film having a retardation, and has a protective function for a polarizing layer, and therefore can also be used as a protective film having a retardation. As long as the physical properties such as retardation in the thickness direction, in-plane retardation, and transparency can be satisfied, the material is not particularly limited. Examples of commercially available retardation films include ZEONOR manufactured by Nippon Zeon Co., Ltd. using norbornene-based cyclic olefins, and n-TAC manufactured by Konica Minolta Opto Co., Ltd., which uses a polymer mainly composed of cellulose ester. V-TAC manufactured by Fuji Film Co., Ltd., and R-film (normal type) and R-40 film (thin film type) manufactured by Kaneka Co., Ltd. are examples of polycarbonate-based stretched films.

The optical compensation film of the present invention includes a liquid crystal compound-coated optical compensation film compatible with large liquid crystal displays and 3D displays, polyimide-oriented optical compensation films, cellulose-based and cycloolefin-based sequential biaxially stretched and obliquely stretched optical compensation films, and the like. Can be used. Since it has a protective function for the polarizing layer, it can also be used as a protective film having an optical compensation function. If the target optical compensation performance can be satisfied, the material is not particularly limited. As an example of a commercially available optical compensation film, WV film-SA (an alignment film made of a polyvinyl alcohol-based resin is formed on one side of a triacetyl cellulose film, and a discotic liquid crystal is coated thereon. And the like.).

In addition, when providing a protective film etc. on both sides of a PVA-type polarizing film, the same polymer material may be used by the front and back, and the protective film which consists of a different polymer material etc. may be used. Further, one or both surfaces may be a retardation film or an optical compensation film instead of the protective film.

In the protective film, retardation film and optical compensation film used in the present invention, the thickness can be appropriately determined. Generally, from the viewpoint of strength, workability during handling, thin layer properties, etc. It is about 500 μm. In particular, 1 to 300 μm is preferable, and 5 to 200 μm is more preferable.

An anchoring process such as applying an easy-adhesion layer is not particularly required on the surface where the protective film, retardation film, or optical compensation film of the present invention is bonded to the polarizing film, but the process may be performed. Examples of the anchor treatment include corona discharge treatment, atmospheric pressure plasma treatment, and a method of coating with a coating agent. The coating agent for coating should just provide the wettability and adhesiveness which were excellent to the protective film, retardation film, and optical compensation film. Specific examples include a polyester resin, a (meth) acrylic resin, a urethane acrylic resin, a silicon acrylic resin, a melamine resin, and a polysiloxane resin.

The thickness of the adhesive layer when the active energy ray-curable adhesive of the present invention is applied to the polarizing film, protective film and / or retardation film, or optical compensation film is not particularly limited, but is usually 0.01. ˜20 μm is preferable, 0.02 to 10 μm is more preferable, and 0.5 to 5 μm is particularly preferable. If the thickness of the adhesive layer is less than 0.01 μm, peeling may easily occur due to insufficient adhesive strength. On the other hand, if the thickness exceeds 20 μm, the transparency of the adhesive layer may be impaired.

If it can apply | coat uniformly so that the thickness of an adhesive bond layer may be 0.01-20 micrometers, the application | coating method is suitably selected according to the viscosity of an adhesive agent or the target thickness. Examples of the coating method include spin coating, spray coating, dipping, gravure roll, knife coating, reverse roll, screen printing, bar coater, and roll-to-roll. Further, the temperature of the adhesive before coating can be appropriately adjusted depending on the viscosity of the adhesive and the blending amount of the permeable component, but the heat resistance temperature of the polarizing film, the protective film, the retardation film, and the optical compensation film is considered, and 20 It is preferable that it is -80 degreeC.

The polarizing plate of the present invention is a laminated film in which the polarizing film and a protective film and / or a retardation film, or an optical compensation film are bonded together through an adhesive layer formed of an active energy ray-curable adhesive. The manufacturing method is not particularly limited. For example, a protective film or retardation film, a method of applying an adhesive on one side of an optical compensation film and then bonding to a polarizing film, a protective film or retardation film after applying an adhesive on one or both sides of the polarizing film, Examples of the method include laminating with an optical compensation film, and laminating a polarizing film with a protective film and / or a retardation film and an optical compensation film using a roll laminator. Since the penetrating power of the penetrating component in the adhesive is directly proportional to the temperature, it is preferable to heat the roll to 40 to 80 ° C. or heat-treat at 40 to 80 ° C. for 0.02 to 30 minutes after bonding.

EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to this. In the following synthesis examples, examples, and comparative examples, parts and% represent parts by weight and% by weight, respectively.

In the following synthesis examples and comparative synthesis examples,% other than yield represents weight% unless otherwise specified. Also, urethane (meth) acrylamide monomer or oligomer (hereinafter abbreviated as urethane acrylamide oligomer (UAAmO)) and urethane (meth) acrylamide polymer (hereinafter abbreviated as urethane acrylamide polymer (UAAmP)) obtained in Synthesis Examples and Comparative Synthesis Examples. The physical property analysis was performed by the following method.

Molecular weight measurement: The weight average molecular weight of the obtained UAAmP was measured by high performance liquid chromatography (manufactured by Shimadzu Corporation, “LC-10A”, column: Shodex GPC KF-806L (exclusion limit molecular weight: 2 × 10 ⁷ , separation range). : 100 to 2 × 10 ⁷ , theoretical plate number: 10,000 plate / piece, filler material: styrene-divinylbenzene copolymer, filler particle size: 10 μm in series), measured in terms of standard polystyrene molecular weight Calculated by
Viscosity measurement: Cone plate type viscometer (device name: RE550 type viscometer manufactured by Toki Sangyo Co., Ltd.) is used and obtained in each synthesis example and comparative synthesis example at a predetermined temperature according to JIS K5600-2-3. The viscosity of UAAmP was measured.
Measurement of glass phase transition temperature (Tg): UAAmP obtained in each synthesis example and comparative synthesis example was dissolved in an appropriate solvent and coated on a PET film. After removing the solvent by heating, it was cured by irradiating with ultraviolet rays in the same manner as the production of the polarizing plate described later. 10 mg was taken out from the obtained hardened layer, put in an aluminum pan, sealed, and measured at a rate of temperature increase of 10 ° C./min using a differential scanning calorimeter (EXSTAR 6000, manufactured by SII Nanotechnology Co., Ltd.). .

Synthesis Example 1 Synthesis of urethane acrylamide oligomer UAAmO-1 122.8 g (0.87 mol) of AOI in a 1 L five-necked flask equipped with a stirrer, thermometer, cooler, dropping funnel and dry air introduction tube, dibutyltin 0.1 g of dilaurate and 180 g of dimethylformamide (DMF) were charged. Next, under dry air flow, 100.0 g (0.87 mol) of N-hydroxyethylacrylamide (KJ Chemicals, trade name “HEAA”) to which 0.3 g of methylhydroquinone (MHQ) was added, while paying attention to heat generation, 5 The solution was gradually added dropwise at 2 ° C. over 2 hours to carry out a urethanization reaction. After completion of the dropping, aging was performed at 10 ° C. for 4 hours. The solvent was distilled off by a reduced pressure method to obtain 220 g of urethane acrylamide oligomer UAAmO-1 as a pale yellow liquid, and the yield was 98.6%. It was analyzed by infrared absorption spectrum (IR), specific absorption of the isocyanate group of AOI, which is a raw material (2260cm ^-1) disappeared completely, also, "HEAA" specific absorption of the double bond derived from (1620cm ^-1 ), The specific absorption (1650 cm ⁻¹ ) of the amide group derived from “HEAA” and the specific absorption (1740 cm ⁻¹ ) of the urethane bond formed were detected, confirming the production of the desired UAAmO-1.

Synthesis Example 2 Synthesis of Urethane Acrylamide Oligomer UAAmO-2 Dicyclohexylmethane 4,4′-diisocyanate (HMDI, hydrogenated 4, hydrogenated in a 1 L 5-neck flask equipped with a stirrer, thermometer, cooler and dry gas introduction tube 4'-diphenylmethane diisocyanate) 223.0 g (0.85 mol), dibutyltin dilaurate 0.2 g, DMF 300 g and butyl acetate 200 g were charged. Next, under a dry air stream, 224.5 g (1.74 mol) of N-methylhydroxyethylacrylamide (MHEAA) added with 0.3 g of methylhydroquinone (MHQ) was gradually added over 2 hours at 20 ° C. while paying attention to heat generation. The urethanization reaction was carried out dropwise. After completion of the dropping, aging was performed at 40 ° C. for 4 hours. The solvent was distilled off by a reduced pressure method to obtain 429.2 g of urethane acrylamide oligomer UAAmO-2 as a pale yellow liquid, and the yield was 95.8%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-2 was confirmed by IR analysis.

Synthesis Example 3 Synthesis of urethane acrylamide oligomer UAAmO-3 In a 5-liter flask having a capacity of 1 L equipped with a stirrer, thermometer, condenser, and dry gas introduction tube, 174.6 g (0.86 mol) of norbornane diisocyanate (NBDI), dibutyl 0.2 g of tin dilaurate, 250 g of acetonitrile, and 200 g of methyl ethyl ketone were charged. Next, under a dry air stream, 224.5 g (1.74 mol) of N-hydroxyethylmethacrylamide (HEMAA) added with 0.3 g of methylhydroquinone (MHQ) was gradually added at 20 ° C. over 2 hours while paying attention to heat generation. The urethanization reaction was carried out dropwise. After completion of the dropping, aging was performed at 40 ° C. for 4 hours. The solvent was distilled off under reduced pressure to obtain 370.8 g of urethane acrylamide oligomer UAAmO-3 as a pale yellow liquid, and the yield was 92.8%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-3 was confirmed by IR analysis.

Synthesis Example 4 Synthesis of Urethane Acrylamide Oligomer UAAmO-4 191.1 g (0.86 mol) of isophorone diisocyanate (IPDI) and dibutyl were added to a 2 L five-necked flask equipped with a stirrer, thermometer, condenser and dry gas introduction tube. 0.5 g of tin dilaurate, 300 g of acetonitrile, and 500 g of methyl ethyl ketone were charged. Next, under dry air flow, 276.6 g (1.74 mol) of N, N′-dihydroxyethylacrylamide (DHEAA) to which 0.5 g of methylhydroquinone (MHQ) was added was heated at 10 ° C. for 2 hours while paying attention to heat generation. The solution was gradually added dropwise to carry out a urethanization reaction. After completion of the dropping, aging was performed at 30 ° C. for 6 hours. The solvent was distilled off by a reduced pressure method to obtain 438.7 g of urethane acrylamide oligomer UAAmO-4 as a pale yellow liquid, and the yield was 93.6%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-4 was confirmed by IR analysis.

Synthesis Example 5 Synthesis of urethane acrylamide oligomer UAAmO-5 252.3 g of isocyanurate (trimer of HDI, abbreviated as TPA) was added to a 2 L 5-neck flask equipped with a stirrer, thermometer, condenser and dry gas introduction tube. (0.5 mol), 0.3 g of dibutyltin dilaurate, 300 g of DMF, and 300 g of ethyl acetate were charged. Next, under dry air flow, 387.0 g (1.74 mol) of N-hydroxypropylacrylamide (HPAA) added with 0.5 g of methylhydroquinone (MHQ) was gradually added at 30 ° C. over 2 hours while paying attention to heat generation. It was dripped and urethanation reaction was performed. After completion of the dropping, aging was performed at 50 ° C. for 6 hours. The solvent was distilled off by a reduced pressure method to obtain 601.7 g of urethane acrylamide oligomer UAAmO-5 as a pale yellow liquid, and the yield was 94.0%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-5 was confirmed by IR analysis.

Synthesis Example 6 Synthesis of urethane acrylamide polymer UAAmP-1 75.0 g of polypropylene glycol (PPG, number average molecular weight: 1500) was added to a 500 mL four-necked flask equipped with a stirrer, a thermometer, a cooler, and a dry gas introduction tube. 0.05 mol), 13.4 g (0.08 mol) of hexamethylene diisocyanate (HDI), 0.05 g of dibutyltin dilaurate, 60 g of DMF and 60 g of butyl acetate, and allowed to react at 70 ° C. for 2 hours while passing dry nitrogen. It was. Next, after cooling the reaction solution to 40 ° C., 0.2 g of MHQ was added, and dry air was bubbled for 10 minutes. Then, 5.8 g (0.05 mol) of “HEAA” was charged, and stirring was continued for 10 hours while maintaining the system temperature at 40 ° C. under an air stream of dry air. The solvent was distilled off by a reduced pressure method to obtain 93.0 g of urethane acrylamide polymer UAAmP-1 as a light yellow viscous liquid, and the yield was 98.7%. Analyzing by infrared absorption spectrum (IR), the characteristic absorption (2270 cm ⁻¹ ) of the isocyanate group of HDI as a raw material disappeared completely, and the characteristic absorption (1100 cm ⁻¹ ) of the ether group derived from PPG, “ HEAA "specific absorption of the double bonds derived from the (1620 cm ^-1), by specific absorption of amide groups derived from" HEAA "(1650 cm ^-1) and specific absorption of the urethane bond to generate (1740 cm ^-1) was detected The production of the target UAAmP-1 was confirmed. The obtained UAAmP-1 had a weight average molecular weight of 4000, a viscosity at 60 ° C. of 3200 mPa · s, and a Tg of −15.3 ° C.

Synthesis Example 7 Synthesis of Urethane Acrylamide Polymer UAAmP-2 Using the same apparatus as in Synthesis Example 6, 150 g (0.05 mol) of polytetramethylene ether glycol (PTMG) (number average molecular weight: 3000), HDI under a dry nitrogen stream. 5 g (0.11 mol), 0.1 g of dibutyltin dilaurate, 120 g of acetonitrile and 120 g of methyl ethyl ketone were charged and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, after cooling the reaction solution to 60 ° C., 0.2 g of MHQ was added, and dry air was bubbled for 10 minutes. Then, 15.5 g (0.12 mol) of MHEAA was charged, and stirring was continued for 10 hours while maintaining the system temperature at 40 ° C. under a stream of dry air. The solvent was distilled off by a reduced pressure method to obtain 181.2 g of urethane acrylamide polymer UAAmP-2 as a light yellow viscous liquid, and the yield was 98.5%. In the same manner as in Synthesis Example 6, formation of the desired UAAmP-2 was confirmed by IR analysis. The obtained UAAmP-2 had a weight average molecular weight of 5000, a viscosity at 60 ° C. of 9600 mPa · s, and a Tg of −15.9 ° C.

Synthesis Example 8 Synthesis of Urethane Acrylamide Polymer UAAmP-3 Using the same apparatus as Synthesis Synthesis Example 6, both ends hydroxyl group polybutadiene (G-1000, manufactured by Nippon Soda Co., Ltd., number average molecular weight: 1400, abbreviation PBD) under a dry nitrogen stream. 0 g (0.05 mol), IPDI 15.5 g (0.07 mol), dibutyltin dilaurate 0.1 g, DMF 150 g and ethyl acetate 100 g were charged and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, after cooling the reaction solution to 40 ° C., 0.2 g of MHQ was added, and dry air was bubbled for 10 minutes. Then, 4.6 g (0.04 mol) of “HEAA” was charged, and stirring was continued for 10 hours while maintaining the temperature in the system at 60 ° C. under a stream of dry air. The solvent was distilled off by a reduced pressure method to obtain 87.9 g of urethane acrylamide polymer UAAmP-3 as a light yellow viscous liquid, and the yield was 97.6%. In the same manner as in Synthesis Example 6, formation of the desired UAAmP-3 was confirmed by IR analysis. The obtained UAAmP-3 had a weight average molecular weight of 8,000, a viscosity at 60 ° C. of 8 million Pa · s, and a Tg of −5.1 ° C.

Synthesis Example 9 Synthesis of Urethane Acrylamide Polymer UAAmP-4 Using the same apparatus as in Synthesis Example 6, PBD 70.0 g (0.05 mol), HDI 11.8 g (0.07 mol), dibutyltin dilaurate 0. 2 g and 200 g of DMF were charged and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, after cooling the reaction solution to 40 ° C., 0.2 g of MHQ was added, and dry air was bubbled for 10 minutes. Then, 2.3 g (0.02 mol) of “HEAA” was charged, and stirring was continued for 10 hours while maintaining the system temperature at 40 ° C. under a stream of dry air. The solvent was distilled off by a reduced pressure method to obtain 82.6 g of urethane acrylamide polymer UAAmP-4 as a light yellow viscous liquid, and the yield was 98.2%. In the same manner as in Synthesis Example 6, formation of the desired UAAmP-4 was confirmed by IR analysis. The obtained UAAmP-4 had a weight average molecular weight of 12,000, a viscosity at 60 ° C. of 54,000 mPa · s, and a Tg of −12.7 ° C.

Synthesis Example 10 Synthesis of urethane acrylamide oligomer UAAmO-6 In a 300 mL four-necked flask equipped with a stirrer, a thermometer, a cooler, and a dry gas introduction tube, an aliphatic cyclic structure-containing polycarbonate polyol (manufactured by Ube Industries, Ltd.) UC-100) 50.0 g (0.05 mol) was added, IPDI 22.2 g (0.10 mol) and toluene 18.1 g were added, and the reaction was carried out at 80 ° C. for 3 hours while suppressing exotherm. A toluene solution of urethane prepolymer (I) having an isocyanate group was obtained. Next, 14.5 g of DMF was added to the toluene solution cooled to 40 ° C. and mixed. Thereafter, 7.4 g (0.04 mol) of isophoronediamine was charged and reacted at 60 ° C. for 3 hours to obtain a solution of urethane urea polymer (II) having an isocyanate group at the molecular end. Next, 0.05 g of MHQ and 8.0 g (0.07 mol) of “HEAA” were mixed in the urethane urea polymer (II) solution and reacted at 70 ° C. for 1 hour. The solvent was distilled off under reduced pressure to obtain 81.1 g of urethane acrylamide oligomer UAAmO-6 as a pale yellow liquid, and the yield was 92.5%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-6 was confirmed by IR analysis.

Synthesis Example 11 Synthesis of urethane acrylamide oligomer UAAmO-7 DMF 50.0 g, 1,2-ethanedithiol 7.06 g (0) in a 200 mL four-necked flask equipped with a stirrer, thermometer, cooler, dry gas inlet tube, and dropping funnel 0.08 mol) was added, and a mixture of 21.9 g (0.13 mol) of HDI and 0.04 g of dibutyltin dilaurate was added dropwise from the dropping funnel over 30 minutes while stirring at room temperature. Thereafter, the temperature was raised from room temperature to 40 ° C., and the reaction was continued for 3 hours to obtain a thiourethane solution. Subsequently, 0.05 g of MHQ and 16.8 g (0.13 mol) of HEMAA were added to the thiourethane solution and reacted at 70 ° C. for 1 hour. The solvent was distilled off by a vacuum method to obtain 89.7 g of urethane acrylamide oligomer UAAmO-7 as a pale yellow liquid, and the yield was 93.6%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-7 was confirmed by IR analysis.

Synthesis Example 12 Synthesis of urethane acrylamide oligomer UAAmO-8 In a 1 L four-necked flask equipped with a stirrer, a thermometer, a condenser, and a dry gas introduction tube, 58.1 g (0.35 mol) of isophthalic acid and 120.1 g of HDI (0. 71 mol) and 250 g of N-methylpyrrolidone were charged and the temperature was raised to 160 ° C., followed by reaction for 3 hours to obtain an amide solution. Subsequently, 0.2 g of MHQ and 91.6 g (0.71 mol) of HPAA were added to the amide solution and reacted at 70 ° C. for 1 hour. The solvent was distilled off under reduced pressure to obtain 248.4 g of urethane acrylamide oligomer UAAmO-8 as a pale yellow liquid, and the yield was 92.0%. In the same manner as in Synthesis Example 1, formation of the desired UAAmO-8 was confirmed by IR analysis.

Synthesis Example 13 Synthesis of urethane acrylamide polymer UAAmP-5 187.5 g (0.13 mol) of PTMG (number average molecular weight: 3000) in a 500 mL four-necked flask equipped with a stirrer, thermometer, condenser and dry gas introduction tube ), 21.8 g (0.13 mol) of HDI, 0.2 g of dibutyltin dilaurate and 180 g of DMF were charged and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, after the reaction solution was cooled to 40 ° C., 0.02 g of MHQ was added, and dry air was bubbled for 10 minutes. Then, 0.5 g (4.3 mmol) of “HEAA” was charged, and stirring was continued for 10 hours while maintaining the system temperature at 40 ° C. under a stream of dry air. The solvent was distilled off by a reduced pressure method to obtain 207.3 g of a waxy urethane acrylamide polymer UAAmP-5, and the yield was 98.7%. In the same manner as in Synthesis Example 6, formation of the desired UAAmP-5 was confirmed by IR analysis. The obtained UAAmP-5 had a weight average molecular weight of 190,000, a viscosity at 60 ° C. of 2 million mPa · s or more, and a Tg of −15.5 ° C.

Synthesis Example 14 Synthesis of Urethane Acrylamide Polymer UAAmP-6 Using the same apparatus as in Synthesis Example 13, 70 g (0.05 mol) of PBD, 11.8 g (0.07 mol) of HDI, 0.1 g of dibutyltin dilaurate under a dry nitrogen stream 200 g of THF was charged and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, after cooling the reaction solution to 40 ° C., 0.2 g of MHQ was added, and dry air was bubbled for 10 minutes. Then, 4.1 g (0.02 mol) of N- [2- (3,4-dihydroxyphenyl) ethyl] acrylamide (synthesized with reference to ACS Macro Letters (2013), 2 (2), 112-115) was charged, Stirring was continued for 10 hours while maintaining the system temperature at 40 ° C. under a stream of dry air. The solvent was distilled off by a reduced pressure method to obtain 84.4 g of urethane acrylamide polymer UAAmP-4 as a light yellow viscous liquid, and the yield was 98.2%. In the same manner as in Synthesis Example 6, formation of the desired UAAmP-6 was confirmed by IR analysis. The obtained UAAmP-6 had a weight average molecular weight of 16000, a viscosity at 60 ° C. of 70000 mPa · s, and a Tg of −10.5 ° C.

Comparative Synthesis Example 1 Synthesis of urethane acrylate oligomer UAO-1 121.4 g (0.86 mol) of AOI and dibutyl in a 500 mL five-necked flask equipped with a stirrer, thermometer, cooler, dropping funnel and dry air introduction tube 0.1 g of tin dilaurate and 180 g of DMF were charged. Next, under a dry air stream, 100 g (0.86 mol) of hydroxyethyl acrylate (HEA) added with 0.3 g of MHQ was gradually added dropwise over 2 hours at 20 ° C. while paying attention to heat generation, to carry out a urethane reaction. . After completion of the dropping, aging was performed at 60 ° C. for 4 hours. The solvent was distilled off by a reduced pressure method to obtain 170.0 g of urethane acrylate oligomer UAO-1 as a pale yellow liquid, and the yield was 76.5%. Analyzed by infrared absorption spectrum (IR), by specific absorption of the double bond derived from HEA (1625 cm ^-1) and specific absorption of the urethane bond to generate (1745 cm ^-1) was detected, formation of a urethane acrylate It was confirmed. On the other hand, the specific absorption (2260 cm ⁻¹ ) of the isocyanate group of the raw material AOI did not completely disappear, and AOI and HEA remained.

Comparative Synthesis Example 2 Synthesis of urethane acrylate oligomer UAO-2 10.0 g of toluene diisocyanate (TDI) was added to a 300 mL five-necked flask equipped with a stirrer, thermometer, cooler, dropping funnel and dry air introduction tube. 06 mol) and 100.0 g (0.69 mol) of hydroxybutyl acrylate (HBA) were added and stirred at room temperature for 4 hours. As a result of analyzing the reaction solution by infrared absorption spectrum (IR), only specific absorption derived from TDI and HBA was confirmed, and formation of urethane bond was not recognized. The reaction solution was heated to 70 ° C. and further aged for 24 hours. As a result of re-analysis of the reaction solution after aging by infrared absorption spectrum (IR), it was confirmed that almost all of TDI and HBA remained, although some urethane bonds were formed.

Comparative Synthesis Example 3 Synthesis of Urethane Acrylate Polymer UAP-1 In a 500 mL four-necked flask equipped with a stirrer, a thermometer, a cooler, and a dry gas introduction tube, 75.0 g of PPG (number average molecular weight: 1500) (0. 05 mol), 13.4 g (0.08 mol) of HDI, 0.05 g of dibutyltin dilaurate, 60 g of DMF and 60 g of butyl acetate, and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, 0.2 g of MHQ was added to the reaction solution, dry air was bubbled for 10 minutes, 5.8 g (0.05 mol) of HEA was charged, and the system temperature was maintained at 80 ° C. under a stream of dry air. Stirring was continued for 10 hours. The solvent was distilled off by a reduced pressure method to obtain 81.6 g of urethane acrylate polymer UAP-1 as a light yellow viscous liquid, and the yield was 86.6%. Analyzed by infrared absorption spectrum (IR), characteristic absorption of ether group derived from PPG (1100 cm ⁻¹ ), characteristic absorption of double bond derived from HEA (1625 cm ⁻¹ ) and characteristic absorption of urethane bond formed (1745 cm ^{− 1} ) was detected, confirming the production of UAP-1. However, a small amount of specific absorption (2260 cm ⁻¹ ) of isocyanate groups derived from raw materials and specific absorption (near 3500 cm ⁻¹ ) derived from hydroxyl groups of PPG and HEA were observed, and residual HDI, PPG or HEA was observed. . The obtained UAP-1 had a weight average molecular weight of 4000, a viscosity at 60 ° C. of 4000 mPa · s or more, and a Tg of −20 ° C.

Comparative Synthesis Example 4 Synthesis of urethane acrylate polymer UAP-2 In a 500 mL four-necked flask equipped with a stirrer, thermometer, cooler, and dry gas introduction tube, 70.0 g of PBD (number average molecular weight: 1400) 05 mol), IPDI 15.5 g (0.07 mol), dibutyltin dilaurate 0.1 g, DMF 100 g and butyl acetate 100 g were charged and reacted at 70 ° C. for 2 hours while passing dry nitrogen. Next, 0.2 g of MHQ was added to the reaction solution, dry air was bubbled for 10 minutes, 5.8 g (0.05 mol) of HEA was charged, and the system temperature was maintained at 80 ° C. under a stream of dry air. Stirring was continued for 10 hours. The solvent was distilled off under reduced pressure to obtain 76.9 g of urethane acrylate polymer UAP-2 as a light yellow viscous liquid, and the yield was 84.2%. As a result of analysis by infrared absorption spectrum (IR), formation of a urethane acrylate polymer was confirmed as in the comparative synthesis example, but residual IPDI, PBD or HEA was observed. The obtained UAP-2 had a weight average molecular weight of 8,300, a viscosity at 60 ° C. of 67,000 mPa · s or more, and a Tg of 0 ° C.

Comparative Synthesis Example 5 Synthesis of urethane acrylamide oligomer UAAmO-9 (see Patent Document 21: JP 2010-054720 A)
HDI 10 g (0.065 mol) and “HEAA” 100.0 g (0.87 mol) were charged in a 300 mL three-necked flask equipped with a stirrer, thermometer, cooler, dropping funnel and dry air introduction tube. Stir at room temperature. A white solid was gradually formed from the start of stirring, and stirring became impossible after 30 minutes to obtain a white solid. The white solid was not dissolved in a solvent such as DMF, ethyl acetate, ethanol, or water, and was confirmed to be a gel.

In the examples and comparative examples of the present invention, the polarizing plate was produced by the following method.
1. Production of polarizing plate by UV irradiation Using a table-type roll laminator machine (RSL-382S manufactured by Royal Sovereign), a polarizing film is sandwiched between two transparent films (protective film, retardation film or optical compensation film), Between the transparent film and the polarizing film, the adhesives of Examples or Comparative Examples were bonded so as to have a thickness of 2 μm. Irradiate ultraviolet rays from the upper surface of the laminated transparent film (apparatus: Inverter type ECS-4011GX manufactured by Eye Graphics, metal halide lamp: M04-L41 manufactured by Eye Graphics, UV illuminance: 700 mW / cm ² , integrated light quantity: 1000 mJ / cm ² ), and a polarizing plate having transparent films on both sides of the polarizing film was prepared.
2. Preparation of polarizing plate by EB irradiation In the same manner as above, bonding was performed using a desktop roll laminator machine, a protective film, a transparent film such as a retardation film or an optical compensation film, a polarizing film, and the adhesives of Examples or Comparative Examples. An electron beam is irradiated from the upper surface of the bonded transparent film (apparatus: Nissin High Voltage Co., Ltd., trade name: Curetron EBC-200-AA3, acceleration voltage: 200 kV, irradiation dose 20 kGy), and both sides of the polarizing film A polarizing plate having a transparent film was prepared.

In Examples and Comparative Examples, the suitability evaluation of the adhesive and the polarizing plate was performed by the following method.
1. Viscosity Measurement A cone plate viscometer (device name: RE550 viscometer manufactured by Toki Sangyo Co., Ltd.) was used, and the viscosity of the adhesive was measured at 25 ° C. according to JIS K5600-2-3.
2. Wetting property evaluation Wetting tension was measured according to JIS K6768. When an adhesive is included in a cotton swab and applied to each of a polarizing film, a protective film, a retardation film, and an optical compensation film, and the liquid film does not break and remains in its original state after 2 seconds. Was determined to be “wet”.
A: The liquid film is not broken and is kept applied for 2 seconds or more;
○: The liquid film is not torn and remains applied for 2 seconds, but starts moving slightly in 2 seconds or more;
Δ: The liquid film is not broken, but the edge starts to move within 2 seconds;
X: The liquid film is broken within 2 seconds, or the whole contracts;
3. Penetration evaluation Penetration evaluation was carried out by our company method. Apply an adhesive to a cotton swab and apply to each of the protective film, retardation film, and optical compensation film. After 5 seconds, wipe with a soft cloth, then wipe further with absorbent cotton soaked in methanol, and observe the coated surface. did.
A: White turbidity (erosion) of the protective film where the adhesive was applied was confirmed;
○: Slight white turbidity was confirmed in the protective film of the part where the adhesive was applied;
(Triangle | delta): The thin trace of adhesive application was confirmed by the protective film of the part which applied the adhesive agent;
X: The portion where the adhesive was applied did not change at all before and after the application;
4). An adhesive tape peeling test in which a polarizing plate (test piece) cut to 20 mm × 150 mm was attached to a tensile tester (Autograph AGXS-X 500N, manufactured by Shimadzu Corporation) under conditions of a peel strength of 23 ° C. and a relative humidity of 50%. A double-sided adhesive tape was attached to the test plate of the apparatus. One piece of the transparent protective film and the polarizing film to which the double-sided adhesive tape is not attached is peeled off in advance by about 20 to 30 mm, chucked on the upper gripping tool, and peeled at 90 ° peel strength (N / 20 mm).
A: 3.0 (N / 20 mm) or more B: 1.5 (N / 20 mm) or more, less than 3.0 (N / 20 mm) Δ: 1.0 (N / 20 mm) or more, 1.5 (N / Less than 20 mm) x: less than 1.0 (N / 20 mm) The adhesive obtained in Examples and Comparative Examples was applied to a polyethylene terephthalate (PET) film having a surface resistivity measurement thickness of 100 μm using a bar coater (No. 3) and irradiated with ultraviolet rays from the upper surface of the film ( Device: Eye Graphics Inverter type conveyor device ECS-4011GX, Metal halide lamp: Eye Graphics M04-L41, UV illuminance: 700 mW / cm ² , Integrated light quantity: 1000 mJ / cm ² ), and a film for measuring surface resistivity Obtained. Subsequently, it was cut into 110 mm × 110 mm under conditions of a temperature of 23 ° C. and a relative humidity of 50% to obtain a test piece for measuring surface resistivity. Based on JIS K 6911, a digital electrometer (R8252 type: manufactured by ADC Corporation) Was used to measure the low surface efficiency.
6). Appearance The transparency of the obtained polarizing plate was visually observed and evaluated according to the following criteria.
A: Neither fine streaks nor unevenness on the surface of the polarizing plate can be confirmed;
○: Minute streaks can be partially confirmed on the surface of the polarizing plate;
Δ: Minute streaks and unevenness on the surface of the polarizing plate can be confirmed;
X: Clear streaks and unevenness on the surface of the polarizing plate can be confirmed;
7). Transparency (haze value)
The obtained polarizing plate was measured for the haze value using a haze meter (Nippon Denshoku Industries Co., Ltd. haze meter NDK2000) and evaluated according to the following criteria.
A: There is no problem in practical use. Haze: less than 0.5;
○: Clouding or the like is not recognized, but haze: 0.5 or more and less than 1;
Δ: Some cloudiness is observed. Haze 1 or more and less than 3;
X: Cloudiness is recognized and there is a problem in practical use. Or haze: 3 or more;
8). Water resistance The obtained polarizing plate was cut into 20 × 80 mm and immersed in warm water at 60 ° C. for 48 hours, and then the presence or absence of peeling at the interface between the polarizer and the protective film, retardation film and optical compensation film was confirmed. The determination was made according to the following criteria.
A: No peeling at the interface between the polarizer and the protective film (less than 1 mm)
○: There is peeling at a part of the interface between the polarizer and the protective film (1 mm or more and less than 3 mm)
Δ: There is peeling at a part of the interface between the polarizer and the protective film (3 mm or more and less than 5 mm)
X: Peeling at the interface between the polarizer and the protective film (5 mm or more)
9. Durability The obtained polarizing plate was cut into 150 mm × 150 mm, put into a thermal shock apparatus (TSA-101L-A manufactured by Espec Corp.), subjected to a heat shock of −40 ° C. to 80 ° C. for 30 minutes, 100 times, and the following Evaluated by criteria.
A: No cracking occurred;
○: Generation of a short crack of 5 mm or less only at the end;
(Triangle | delta): The crack has generate | occur | produced in the short linear form in places other than an edge part. However, the line does not separate the polarizer into two or more parts;
X: Cracks are generated in places other than the edges. The line separates the polarizer into two or more parts;

The materials used in Examples and Comparative Examples are as follows. Moreover, in the following, a part and% show a weight part and weight%, respectively.
“HEAA”: N-hydroxyethylacrylamide (manufactured by KJ Chemicals)
MHEAA: N-methyl-N-hydroxyethylacrylamide (manufactured by KJ Chemicals)
HEMAA: N-hydroxyethyl methacrylamide (manufactured by KJ Chemicals)
HPAA: N-hydroxypropylacrylamide (manufactured by KJ Chemicals)
DHEAA: N, N′-dihydroxyethylacrylamide (manufactured by KJ Chemicals)
4-HBA: 4-hydroxybutyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
HEA: Hydroxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
2-HPA: 2-hydroxypropyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.)
GA: Glycidyl acrylate (manufactured by KJ Chemicals)
GMA: Glycidyl methacrylate (Mitsubishi Gas Chemical Co., Ltd.)
“ACMO”: acryloylmorpholine (manufactured by KJ Chemicals)
“DMAA”: N, N-dimethylacrylamide (manufactured by KJ Chemicals)
“DEAA”: N, N-diethylacrylamide (manufactured by KJ Chemicals)
“NIPAM”: N-isopropylacrylamide (manufactured by KJ Chemicals)
THFA: Tetrahydrofurfuryl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.)
IBMA: N-isobutoxymethylacrylamide (manufactured by MRC Unitech Co., Ltd.)
DMAEA: dimethylaminoethyl acrylate (manufactured by KJ Chemicals)
“DMAPAA”: dimethylaminopropylacrylamide (manufactured by KJ Chemicals)
DMAEA-TFSIQ: acryloyloxyethyltrimethylammonium bis (trifluoromethanesulfonyl) imide (manufactured by KJ Chemicals)
DMAPAA-TFSIQ: acryloylaminopropyltrimethylammonium bis (trifluoromethanesulfonyl) imide (manufactured by KJ Chemicals)
ECC: 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexene carboxylate (manufactured by Daicel Corporation)
GOP: 2,2′-bis (4-glycidyloxyphenyl) propane HDDA: 1,6-hexanediol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)
DCP-A: dimethylol tricyclodecane diacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)
CD536: Cyclohexanedimethanol diacrylate (manufactured by Sartomer Co., Ltd.)
UV6640B: Polyurethane acrylate (manufactured by Nippon Synthetic Chemical)
UV7000B: Polyurethane acrylate (manufactured by Nippon Synthetic Chemical)
Sunduren SD-014: Acrylic protective film manufactured by Kaneka Arton R5000: Cyclic olefin-based protective film manufactured by JSR Co., Ltd. n-TAC: A polymer mainly composed of cellulose ester manufactured by Konica Minolta Opto Co., Ltd. is used. Retardation film WV-SA: an optical compensation film in which a discotic liquid crystal is coated on a TAC film manufactured by Fuji Film Co., Ltd.

Example 1
20 parts by weight of “UAAmO-1” synthesized in Synthesis Example 1, 40 parts by weight of 4-HBA, 20 parts by weight of “DMAA” and 20 parts by weight of GOP were mixed, and BASF (former Ciba Specialty) was used as a photopolymerization initiator. Chemicals), trade name Irgacure 250 3 parts by weight, Darocur TPO 3 parts by weight and 2,4-diethylthioxanthen-9-one 1 part by weight were added and mixed uniformly to prepare an ultraviolet curable adhesive. Then, using the obtained adhesive, polarizing plate preparation and polarizing plate evaluation by ultraviolet curing were performed by the above method. The results are shown in Table 1.

Example 2
15 parts by weight of “UAAmP-1” synthesized in Synthesis Example 2, 50 parts by weight of HEA, 15 parts by weight of THFA, 15 parts by weight of HDDA and 5 parts by weight of UV6640B were mixed, and BASF (former Ciba Special) was used as a photopolymerization initiator. 3 parts by weight of Darocur 1173 manufactured by Tea Chemicals) and 1 part by weight of Irgacure 907 were added and mixed uniformly to prepare an ultraviolet curable adhesive. Then, using the obtained adhesive, polarizing plate preparation and polarizing plate evaluation by ultraviolet curing were performed by the above method. The results are shown in Table 1.

Examples 3, 4, 6-8, 10, 11, 13-18, 21-23, 25, 27
In Example 1, in preparing the active energy ray-curable adhesive, urethane acrylamide oligomer or urethane acrylamide polymer, hydroxyl group-containing monomer, epoxy group-containing monomer, other monofunctional monomer, polymerizable tertiary amine compound, ionic monomer A polarizing plate was produced in the same manner as in Example 1 except that the polyfunctional compounds or their blending amounts were changed as shown in Table 1. Moreover, polarizing plate preparation and polarizing plate evaluation were performed similarly. The results are shown in Tables 1 and 2.

Examples 9, 19, 24, 26
In Example 2, in preparing the active energy ray-curable adhesive, urethane acrylamide oligomer or urethane acrylamide polymer, hydroxyl group-containing monomer, other monofunctional monomer, polymerizable tertiary amine compound, ionic monomer, polyfunctional compound, Or the polarizing plate was produced like Example 2 except having changed those compounding quantities as shown in Table 1. Moreover, polarizing plate preparation and polarizing plate evaluation were performed similarly. The results are shown in Tables 1 and 2.

Examples 5, 12, 20
In preparation of the active energy ray-curable adhesive, urethane acrylamide polymer, hydroxyl group-containing monomer, epoxy group-containing monomer, other monofunctional monomer, polymerizable tertiary amine compound, ionic monomer, polyfunctional compound, or combination thereof The amounts were measured and uniformly mixed as shown in Table 1, and an electron beam curable adhesive was prepared without adding a photopolymerization initiator. Thereafter, using the obtained adhesive, polarizing plate preparation and polarizing plate evaluation by electron beam curing were performed by the above method. The results are shown in Tables 1 and 2.

Comparative Examples 2, 3, 6-9, 11
In Example 1, in preparing the active energy ray-curable adhesive, urethane acrylamide oligomer or urethane acrylamide polymer, urethane acrylate oligomer or urethane acrylate polymer, hydroxyl group-containing monomer, epoxy group-containing monomer, other monofunctional monomer, polymerizable first A polarizing plate was produced in the same manner as in Example 1 except that the tertiary amine compound, ionic monomer, polyfunctional compound, or the blending amount thereof was changed as shown in Table 2. Moreover, the adhesive agent and the polarizing plate were similarly evaluated. The results are shown in Table 3.

Comparative Examples 1, 4, 10, 13
In Example 2, in preparing the active energy ray-curable adhesive, urethane acrylamide oligomer or urethane acrylamide polymer, hydroxyl group-containing monomer, other monofunctional monomer, polymerizable tertiary amine compound, ionic monomer, polyfunctional compound, Or the polarizing plate was produced like Example 2 except having changed those compounding quantities as shown in Table 2. Moreover, polarizing plate preparation and polarizing plate evaluation were performed similarly. The results are shown in Table 3.

Comparative Examples 5 and 12
In preparation of the active energy ray-curable adhesive, urethane acrylamide polymer, hydroxyl group-containing monomer, epoxy group-containing monomer, other monofunctional monomer, polymerizable tertiary amine compound, ionic monomer, polyfunctional compound, or combination thereof The amounts were measured and uniformly mixed as shown in Table 2, and an electron beam curable adhesive was prepared without adding a photopolymerization initiator. Thereafter, using the obtained adhesive, polarizing plate preparation and polarizing plate evaluation by electron beam curing were performed by the above method. The results are shown in Table 3.

From the results of Examples and Comparative Examples, when the adhesive of the present invention does not sufficiently contain urethane (meth) acrylamide, the wettability and adhesion to PVA polarizing film, protective film, retardation film, and optical compensation film are remarkable. It became worse and it turned out that the peeling strength (adhesion strength) of the polarizing plate obtained falls. Moreover, when the compounding quantity of the said urethane (meth) acrylamide is less than the range of this invention, a hydroxyl-containing monomer, an epoxy-containing monomer, another monofunctional monomer, a polymeric tertiary amine compound, an ionic monomer, and a polyfunctional compound Although the improvement of the wettability with respect to a protective film was confirmed a little by mixing | blending, the improvement of the wettability with respect to a polarizing film was not seen. From the above, when urethane (meth) acrylamide is not contained, it is difficult to simultaneously satisfy wettability, adhesion, coating workability, etc. with respect to PVA polarizing film and protective film, retardation film, and optical compensation film. In addition, when the amount of the urethane (meth) acrylamide is larger than the range of the present invention, the viscosity of the composition becomes too high, so that applicability and workability are reduced, and as a result, adhesion unevenness is likely to occur. Therefore, physical properties such as adhesive strength of the adhesive layer, appearance of the polarizing plate, transparency, heat resistance, water resistance and durability are not sufficient. That is, by making urethane (meth) acrylamide an essential component of the adhesive within the scope of the present invention, it has excellent wettability and adhesion to a PVA polarizing film and a protective film, and has a high curing rate. It was found that the obtained polarizing plate had high peel strength (adhesive strength) and transparency, and was able to satisfy heat resistance, water resistance and durability at the same time.

As described above, the active energy ray-curable adhesive for polarizing plate of the present invention contains urethane (meth) acrylamide having at least one (meth) acryloyl group, a PVA polarizing film, Excellent wettability and adhesion to various protective films, retardation films, and optical compensation films, no adhesion unevenness, high adhesive strength and excellent transparency, and high curing speed Yes. If necessary, urethane (meth) acrylamide, hydroxyl group-containing monomer, epoxy group-containing monomer, other single functional monomer, polymerizable tertiary amine compound, ionic monomer, polyfunctional compound, active energy ray polymerization initiator, By mixing and using various thermoplastic resin compositions and various general-purpose additives, the material of the protective film can be selected from any material. Since the polarizing plate produced using the active energy ray-curable adhesive for polarizing plate of the present invention has properties such as transparency, heat resistance, durability, and water resistance, it is suitably used for various optical applications. be able to.

Claims (17)

An active energy ray-curable polarizing plate adhesive used for bonding a protective film made of a transparent resin to at least one surface of a polarizing film made of a polyvinyl alcohol resin, wherein the adhesive is at least one (meth) acryloyl An adhesive for polarizing plates, which contains urethane (meth) acrylamide having a group. The urethane (meth) acrylamide is represented by the following general formula [1] (R ₁ represents a hydrogen atom or a methyl group, and R ₂ and R ₃ are the same or different and may be substituted with a hydrogen atom or a hydroxyl group. A linear or branched alkyl group having 1 to 6 carbon atoms, an aliphatic or aromatic ring having 3 to 6 carbon atoms, and R ₂ and R ₃ together with the nitrogen atom supporting them. In addition, a saturated or unsaturated 5- to 7-membered ring which may further contain an oxygen atom or a nitrogen atom may be formed, provided that R ₂ and R ₃ are hydrogen atoms at the same time, and R ₂ and R ₃ Is obtained by an addition reaction of the compound (A) represented by (A) and a compound (B) having one or more isocyanate groups in one molecule. Claim 1 characterized The adhesive for polarizing plate according.

3. The addition reaction between the compound (A) and the compound (B) is carried out in such a manner that the total number of isocyanate groups in the compound (B) is less than or equal to the total number of hydroxyl groups in the compound (A). The adhesive for polarizing plates of description. Compound (A) is one or more selected from the group consisting of N-hydroxyalkylene (meth) acrylamide, N, N-dihydroxyalkylene (meth) acrylamide and N-alkyl-N-hydroxyalkylene (meth) acrylamide The adhesive for polarizing plates as described in any one of Claims 1 thru | or 3 characterized by the above-mentioned. The compound (B) is a monofunctional isocyanate having one isocyanate group in one molecule and / or a polyfunctional isocyanate having two or more isocyanate groups in one molecule. The adhesive agent for polarizing plates as described in any one of thru | or 4 thru | or 4. The adhesive for polarizing plates according to any one of claims 1 to 5, wherein the polyfunctional isocyanate is aliphatic, aromatic, alicyclic, or a multimer thereof, or an adduct type. Compound (B) having one or more isocyanate groups in one molecule is an addition reaction product of a compound having one or more hydroxyl groups in one molecule and a compound having two or more isocyanate groups in one molecule. The adhesive for polarizing plates according to any one of claims 1 to 6, wherein the total number of isocyanate groups is equal to or greater than the total number of hydroxyl groups. Compound (B) having one or more isocyanate groups in one molecule is an addition reaction product of a compound having one or more carboxyl groups in one molecule and a compound having two or more isocyanate groups in one molecule And the sum total of an isocyanate group is more than an equivalent with respect to the sum total of a carboxyl group, The adhesive agent for polarizing plates as described in any one of Claim 1 thru | or 6 characterized by the above-mentioned. Compound (B) having one or more isocyanate groups in one molecule is an addition reaction product of a compound having one or more thiol groups in one molecule and a compound having two or more isocyanate groups in one molecule And the sum total of an isocyanate group is more than an equivalent with respect to the sum total of a thiol group, The adhesive agent for polarizing plates as described in any one of Claim 1 thru | or 6 characterized by the above-mentioned. Compound (B) having one or more isocyanate groups in one molecule is an addition reaction product of a compound having one or more amine groups in one molecule and a compound having two or more isocyanate groups in one molecule And the sum total of an isocyanate group is more than an equivalent with respect to the sum total of an amine group, The adhesive agent for polarizing plates as described in any one of Claim 1 thru | or 6 characterized by the above-mentioned. 11. The polarizing plate adhesive according to claim 1, wherein the urethane (meth) acrylamide is a monomer or oligomer having a weight average molecular weight of 200 to 4,000. 11. The polarizing plate according to claim 1, wherein the urethane (meth) acrylamide is a polymer having a weight average molecular weight of more than 4,000 and not more than 200,000. 11. adhesive. Furthermore, the adhesive agent for polarizing plates in any one of the Claims 1 thru | or 12 containing the acrylic monomer (C) which has a hydroxyl group. Furthermore, the adhesive agent for polarizing plates in any one of the Claims 1 thru | or 13 containing the acrylic monomer (D) which has an epoxy group. In the adhesive for polarizing plate, the content ratio of urethane (meth) acrylamide and acrylic monomer (C) containing a hydroxyl group is urethane (meth) acrylamide / (C) of 10 to 60% by weight / 40 to 90% by weight. An adhesive for polarizing plates, characterized in that The urethane (meth) acrylamide / epoxy group-containing acrylic monomer (D) content ratio in the polarizing plate adhesive is urethane (meth) acrylamide / (D) of 30 to 95% by weight / 5 to 70% by weight. %, An adhesive for polarizing plates. It is an active energy ray hardening-type polarizing plate adhesive used for bonding the protective film which consists of transparent resin to at least one surface of a polarizing film, Comprising: This adhesive for polarizing plates in any one of Claims 1 thru | or 16 A polarizing plate characterized by being formed of an adhesive.