JP5803870B2 - Adhesive composition containing polyfunctional epoxy group-containing organosilicon compound, adhesive polarizing plate, and liquid crystal display device - Google Patents

Description

  The present invention relates to a pressure-sensitive adhesive composition containing a polyfunctional epoxy group-containing organosilicon compound, and more specifically, by using a silane coupling agent having a plurality of epoxy groups and further including a polyether structure in the structure. Compared with silane coupling agents and polyether compounds used in existing technology, it has excellent bonding power and interaction with matrix resins having hydroxyl groups, so the adhesive between the adhesive containing matrix resins and the substrate , A pressure-sensitive adhesive composition containing an organosilicon compound capable of dramatically improving reworkability, a pressure-sensitive adhesive polarizing plate having a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition, and a liquid crystal display device including the pressure-sensitive adhesive polarizing plate .

  Silane coupling agents have two or more different functional groups in the molecule and act as an intermediary for linking organic materials and inorganic materials that are usually difficult to bond. One of the functional groups is a hydrolyzable silyl group, and a silanol group is generated in the presence of water, and this silanol group reacts with a hydroxyl group on the surface of the inorganic material to form a chemical bond with the surface of the inorganic material. Other functional groups are organic reactive groups such as vinyl groups, epoxy groups, amino groups, (meth) acrylic groups, and mercapto groups that form chemical bonds with organic materials such as various synthetic resins. Using such properties, they are widely used as organic / inorganic resin modifiers, adhesion aids, various additives, and the like.

  Among the applications of silane coupling agents, the typical application is as an adhesive. For example, the adhesive used to attach a liquid crystal cell and an optical film increases the size of a liquid crystal display (LCD). With the widening, the required bonding performance has become advanced.

  In the case of LCD, unlike the initial expectation that it is difficult to increase the size of 20 inches or more, the size is rapidly increasing. Major manufacturers have so far focused on the production of small panels of 20 inches or less, but in response to recent trends, they have actively introduced the latest technology and expanded the product range to large sizes of 20 inches or more. .

  Thus, in various optical films, the glass used at the time of manufacturing a liquid crystal display panel tends to be enlarged. However, if a defective product is generated at the time of initial bonding, the optical film is removed from the liquid crystal cell, and the liquid crystal cell is washed and reused, if a conventional adhesive having a high adhesive force is used. Not only is it difficult to remove the optical film due to its strong adhesive force during the re-peeling of the optical film, but also the possibility of destroying expensive liquid crystal cells is high, resulting in a significant increase in production costs. It is supposed to end.

  Therefore, as LCDs become larger, attempts to develop highly functional pressure-sensitive adhesives that achieve various adhesive properties such as adhesiveness and reworkability are continuing. For example, Japanese Patent No. 3022993 (Patent Document 1) proposes an acrylic pressure-sensitive adhesive composition containing epoxysilane for the purpose of providing a polarizing plate having excellent durability in a high-temperature and high-humidity environment. .

  JP-A-8-104855 (Patent Document 2) not only can attach a polarizing plate to a substrate surface with good adhesive strength, but also damages the substrate or leaves an adhesive if necessary. In order to peel the polarizing plate from the surface of the substrate without causing it, a pressure-sensitive adhesive composition containing an acrylic polymer and a compound having a β-ketoester group and a hydrolyzed silyl group has been proposed.

  By including such a silane compound, the substrate and the polarizing plate can maintain an appropriate adhesive strength to the extent required in the environment in which the substrate is actually used, and the adhesive strength is not excessively increased by heating or the like. The polarizing plate can be easily peeled off without damaging the liquid crystal element.

  However, the performance required of pressure-sensitive adhesives to support the large-size trend of LCDs is that the initial adhesive force when attached to glass is low and not only has excellent reworkability, but also needs to exhibit high adhesiveness under high temperature and high humidity. If this is not the case, bubbles and peeling may occur and durability may be weakened.

  Japanese Patent Application Laid-Open No. 8-199144 (Patent Document 3) discloses a silane-based compound in order to provide a pressure-sensitive adhesive composition having little change over time in cohesive force and adhesive force even under high temperature and high humidity, and having excellent curved surface adhesive force. There has been proposed a technique of blending a curing agent with an acrylic resin obtained by polymerizing an acrylic monomer in the presence of.

  By compounding this silane compound, the substrate and the polarizing plate can maintain an appropriate adhesive strength to the extent required in the environment where they are actually used, and the adhesive strength is not excessively increased by heating, It is described that the polarizing plate can be easily peeled without damaging the liquid crystal element.

  However, it can be said that it is preferable that the adhesive force is high, there is no bubble or peeling phenomenon, and the durability is superior to the fact that the change with time of the cohesive force and adhesive force is small under high temperature and high humidity. That is, it shows an appropriate initial adhesive strength that can be re-peeled at the initial stage when it is pasted on glass, but it does not need to be peeled off as time passes, so it maintains a strengthened and stabilized adhesive strength. Can be said to be necessary.

  JP 2008-506028 A (Patent Document 4) discloses an adhesive having low initial adhesive strength, excellent reworkability, enhanced adhesive strength under high temperature and high humidity after pasting, and excellent durability in the long term. An acrylic pressure-sensitive adhesive containing a silane coupling agent having a urethane functional group and a pyridine functional group has been proposed.

  However, the silane coupling agent is obtained by reacting an isocyanate silane with 2-pyridinol in the presence of a catalyst, and the hydroxyl group of 2-pyridinol is not present in both the isocyanate group and the hydrolyzable silyl group of the silane. Since it reacts selectively, since it is not a single structure like the disclosed silane, improvement of various adhesive properties is also insufficient.

  JP 2011-219765 A (Patent Document 5), Japanese Patent No. 4840888 (Patent Document 6), and International Publication No. 2010/26995 (Patent Document 7) have low initial adhesive strength and excellent reworkability. An acrylic pressure-sensitive adhesive containing an organosilicon compound having an alkoxysilyl group at the polyether end has been proposed as a pressure-sensitive adhesive that has enhanced adhesion under high temperature and high humidity after sticking and has excellent durability over the long term.

  However, the rework characteristics that can be improved with the organosilicon compound, the moisture resistance after bonding, the adhesive strength, and the like cannot be said to be sufficient, and there remains room for improvement.

  In addition, although the silane coupling agent which has a some epoxy group in a molecule | numerator is disclosed in Unexamined-Japanese-Patent No. 2009-275015 (patent document 8), the application of this material is only a coating agent, There is no description as an additive.

  From the above, it has been desired to develop a pressure-sensitive adhesive that retains initial reworkability and high adhesive strength under high temperature and high humidity.

Japanese Patent No. 3022993 JP-A-8-104855 JP-A-8-199144 Special table 2008-506028 gazette JP 2011-219765 A Japanese Patent No. 4840888 International Publication No. 2010/26995 JP 2009-275015 A

  The present invention has been made in view of the above circumstances, and when pasted on an adherend such as glass, the initial adhesive force is low and excellent in reworkability, and after pasting, under high temperature or high temperature and high humidity conditions. Adhesive composition capable of forming a pressure-sensitive adhesive layer excellent in long-term durability with increased adhesion to an adherend such as glass, a pressure-sensitive adhesive polarizing plate having a pressure-sensitive adhesive layer formed from this pressure-sensitive adhesive composition, and It aims at providing the liquid crystal display device which has this adhesion polarizing plate.

  As a result of intensive studies in order to achieve the above object, the present inventor has two or more epoxy groups for one alkoxysilyl group or silanol group present in the molecule, and further links organic groups. By incorporating a silane coupling agent containing a polyether structural group as a chain into the pressure-sensitive adhesive composition as an essential component, it is possible to achieve both initial reworkability and high adhesive strength at high temperature or high temperature and high humidity. As a result, the inventors have made the present invention.

［式中、Ｒは水素原子、グリシジル基、及び下記式（２）

（式中、Ｒ’は炭素数１〜６のアルキル基を示し、Ｘは水素原子又は炭素数１〜４のアルキル基を示し、ｎは１〜３の整数、ｍは１〜１０の整数である。）
で示される基から選ばれ、Ｒの少なくとも１つは前記式（２）の基であって、Ｒの少なくとも２つはグリシジル基であり、ａは１≦ａ≦１００の数である。］
で表される多官能エポキシ基含有有機ケイ素化合物： ０．０１〜９質量部
を含むことを特徴とする粘着剤組成物。
［２］
（Ａ）（ａ）炭素数１〜１２のアルキル基を有する（メタ）アクリル酸エステルモノマー９０〜９９．９質量部と、（ｂ）架橋可能な官能基を含むビニル系モノマー及び／又は（メタ）アクリル系モノマー０．１〜１０質量部とを共重合して得られる（メタ）アクリル系共重合体： １００質量部、
（Ｂ）多官能性架橋剤： ０．０１〜１０質量部、
（Ｃ）下記一般式（３）

［式中、Ｒは水素原子、グリシジル基、及び下記式（２）

（式中、Ｒ’は炭素数１〜６のアルキル基を示し、Ｘは水素原子又は炭素数１〜４のアルキル基を示し、ｎは１〜３の整数、ｍは１〜１０の整数である。）
で示される基から選ばれ、Ｒの少なくとも１つは前記式（２）の基であって、Ｒの少なくとも２つはグリシジル基であり、ＡＯは炭素数２〜６のアルキレンオキシド構造基であり、ｂ、ｃ、ｄ、ｅはそれぞれ４≦ｂ≦１０、０≦ｃ≦１０、０≦ｄ≦１０、０≦ｅ≦１０の数である。］
で表される多官能エポキシ基含有有機ケイ素化合物： ０．０１〜９質量部
を含むことを特徴とする粘着剤組成物。
［３］
（Ａ）（ａ）炭素数１〜１２のアルキル基を有する（メタ）アクリル酸エステルモノマー９０〜９９．９質量部と、（ｂ）架橋可能な官能基を含むビニル系モノマー及び／又は（メタ）アクリル系モノマー０．１〜１０質量部とを共重合して得られる（メタ）アクリル系共重合体： １００質量部、
（Ｂ）多官能性架橋剤： ０．０１〜１０質量部、
（Ｃ）下記一般式（１）

［式中、Ｒは水素原子、グリシジル基、及び下記式（２）

（式中、Ｒ’は炭素数１〜６のアルキル基を示し、Ｘは水素原子又は炭素数１〜４のアルキル基を示し、ｎは１〜３の整数、ｍは１〜１０の整数である。）
で示される基から選ばれ、Ｒの少なくとも１つは前記式（２）の基であって、Ｒの少なくとも２つはグリシジル基であり、ａは１≦ａ≦１００の数である。］
で表される多官能エポキシ基含有有機ケイ素化合物、及び下記一般式（３）

［式中、Ｒは水素原子、グリシジル基、及び下記式（２）

（式中、Ｒ’は炭素数１〜６のアルキル基を示し、Ｘは水素原子又は炭素数１〜４のアルキル基を示し、ｎは１〜３の整数、ｍは１〜１０の整数である。）
で示される基から選ばれ、Ｒの少なくとも１つは前記式（２）の基であって、Ｒの少なくとも２つはグリシジル基であり、ＡＯは炭素数２〜６のアルキレンオキシド構造基であり、ｂ、ｃ、ｄ、ｅはそれぞれ４≦ｂ≦１０、０≦ｃ≦１０、０≦ｄ≦１０、０≦ｅ≦１０の数である。］
で表される多官能エポキシ基含有有機ケイ素化合物： ０．０１〜９質量部
を含むことを特徴とする粘着剤組成物。
［４］
（ｂ）架橋可能な官能基を含むビニル系モノマー又は（メタ）アクリル系モノマーが、２−ヒドロキシエチル（メタ）アクリレート、３−ヒドロキシプロピル（メタ）アクリレート、４−ヒドロキシブチル（メタ）アクリレート、ジエチレングリコールモノ（メタ）アクリレート、ジプロピレングリコールモノ（メタ）アクリレート、（メタ）アクリロキシプロピルトリメトキシシラン、（メタ）アクリロキシプロピルトリエトキシシラン、（メタ）アクリロキシプロピルメチルジメトキシシラン、（メタ）アクリロキシプロピルメチルジエトキシシラン、（メタ）アクリロキシメチルトリメトキシシラン、（メタ）アクリロキシメチルトリエトキシシラン、（メタ）アクリロキシメチルメチルジメトキシシラン、（メタ）アクリロキシメチルメチルジエトキシシラン、（メタ）アクリル酸、（メタ）アクリル酸二量体、イタコン酸、マレイン酸及びマレイン酸無水物からなる群より選ばれる１種以上のモノマーである［１］〜［３］のいずれかに記載の粘着剤組成物。
［５］
（Ｂ）多官能性架橋剤が、イソシアネート系化合物、エポキシ系化合物、アジリジン系化合物及び金属キレート系化合物からなる群より選ばれる１種以上の架橋剤である［１］〜［４］のいずれかに記載の粘着剤組成物。
［６］
硬化物の架橋密度が５〜９５質量％である［１］〜［５］のいずれかに記載の粘着剤組成物。
［７］
偏光フィルムと、この偏光フィルムの片面又は両面に［１］〜［６］のいずれかに記載の粘着剤組成物から形成される粘着剤層とを有することを特徴とする粘着偏光板。
［８］
更に、保護層、反射層、位相差板、光視野角補償フィルム及び輝度向上フィルムからなる群より選択される１種以上の層を有する［７］記載の粘着偏光板。
［９］
一対のガラス基板間に液晶が封入された液晶セルと、この液晶セルの片面又は両面に貼着された［７］又は［８］記載の粘着偏光板とを有する液晶パネルを含むことを特徴とする液晶表示装置。 Accordingly, the present invention provides the following pressure-sensitive adhesive composition, pressure-sensitive adhesive polarizing plate and liquid crystal display device.
[1]
(A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and (b) a vinyl monomer and / or (meta ) (Meth) acrylic copolymer obtained by copolymerizing 0.1-10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) The following general formula (1)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the formula (2), at least two of R are glycidyl groups, and a is a number satisfying 1 ≦ a ≦ 100. ]
A pressure-sensitive adhesive composition comprising 0.01 to 9 parts by mass of a polyfunctional epoxy group-containing organosilicon compound represented by :
[2]
(A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and (b) a vinyl monomer and / or (meta ) (Meth) acrylic copolymer obtained by copolymerizing 0.1-10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) The following general formula (3)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the above formula (2), at least two of R are glycidyl groups, and AO is an alkylene oxide structural group having 2 to 6 carbon atoms. , B, c, d, and e are numbers of 4 ≦ b ≦ 10, 0 ≦ c ≦ 10, 0 ≦ d ≦ 10, and 0 ≦ e ≦ 10, respectively. ]
A pressure-sensitive adhesive composition comprising 0.01 to 9 parts by mass of a polyfunctional epoxy group-containing organosilicon compound represented by :
[3]
(A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and (b) a vinyl monomer and / or (meta ) (Meth) acrylic copolymer obtained by copolymerizing 0.1-10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) The following general formula (1)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the formula (2), at least two of R are glycidyl groups, and a is a number satisfying 1 ≦ a ≦ 100. ]
And a polyfunctional epoxy group-containing organosilicon compound represented by the following general formula (3)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the above formula (2), at least two of R are glycidyl groups, and AO is an alkylene oxide structural group having 2 to 6 carbon atoms. , B, c, d, and e are numbers of 4 ≦ b ≦ 10, 0 ≦ c ≦ 10, 0 ≦ d ≦ 10, and 0 ≦ e ≦ 10, respectively. ]
A pressure-sensitive adhesive composition comprising 0.01 to 9 parts by mass of a polyfunctional epoxy group-containing organosilicon compound represented by :
[ 4 ]
(B) A vinyl monomer or (meth) acrylic monomer containing a crosslinkable functional group is 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, diethylene glycol Mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, (meth) acryloxypropyltrimethoxysilane, (meth) acryloxypropyltriethoxysilane, (meth) acryloxypropylmethyldimethoxysilane, (meth) acryloxy Propylmethyldiethoxysilane, (meth) acryloxymethyltrimethoxysilane, (meth) acryloxymethyltriethoxysilane, (meth) acryloxymethylmethyldimethoxysilane, (meth) acryloxymethyl Methyl diethoxy silane, (meth) acrylic acid, (meth) acrylic acid dimer, itaconic acid, one or more monomers selected from the group consisting of maleic acid and maleic anhydride [1] to [3] The pressure-sensitive adhesive composition according to any one of the above.
[ 5 ]
(B) Any one of [ 1 ] to [4], wherein the polyfunctional crosslinking agent is at least one crosslinking agent selected from the group consisting of an isocyanate compound, an epoxy compound, an aziridine compound and a metal chelate compound. 2. The pressure-sensitive adhesive composition according to 1.
[ 6 ]
The pressure-sensitive adhesive composition according to any one of [1] to [ 5 ], wherein the cured product has a crosslinking density of 5 to 95% by mass.
[ 7 ]
A pressure-sensitive adhesive polarizing plate comprising a polarizing film and a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition according to any one of [1] to [ 6 ] on one side or both sides of the polarizing film.
[ 8 ]
Furthermore, the pressure-sensitive adhesive polarizing plate according to [ 7 ], further comprising at least one layer selected from the group consisting of a protective layer, a reflective layer, a retardation plate, a light viewing angle compensation film, and a brightness enhancement film.
[ 9 ]
It includes a liquid crystal panel having a liquid crystal cell in which liquid crystal is sealed between a pair of glass substrates, and an adhesive polarizing plate described in [ 7 ] or [ 8 ] attached to one or both surfaces of the liquid crystal cell, Liquid crystal display device.

  The pressure-sensitive adhesive composition of the present invention has two or more epoxy groups for one alkoxysilyl group or silanol group present in the molecule, and further includes a polyether structure group as a connecting chain of organic groups. By blending such a silane coupling agent as an essential component, it is possible to achieve both initial reworkability and high adhesive strength at high temperature or high temperature and high humidity.

4 is a diagram showing an IR spectrum before the reaction of Synthesis Example 1. FIG. 4 is a diagram showing an IR spectrum during the reaction of Synthesis Example 1. FIG. It is a figure which shows IR spectrum after completion | finish of reaction of the synthesis example 1. FIG.

  Hereinafter, the present invention will be specifically described. In the present invention, the “silane coupling agent” is included in the “organosilicon compound”.

［式中、Ｒは水素原子、グリシジル基、及び下記式（２）

（式中、Ｒ’は炭素数１〜６のアルキル基を示し、Ｘは水素原子又は炭素数１〜４のアルキル基を示し、ｎは１〜３の整数、ｍは１〜１０の整数である。）
で示される基から選ばれ、Ｒの少なくとも１つは前記式（２）の基であって、Ｒの少なくとも２つはグリシジル基であり、ａは１≦ａ≦１００の数である。］、及び下記一般式（３）

［式中、Ｒは水素原子、グリシジル基、及び下記式（２）

（式中、Ｒ’は炭素数１〜６のアルキル基を示し、Ｘは水素原子又は炭素数１〜４のアルキル基を示し、ｎは１〜３の整数、ｍは１〜１０の整数である。）
で示される基から選ばれ、Ｒの少なくとも１つは前記式（２）の基であって、Ｒの少なくとも２つはグリシジル基であり、ＡＯは炭素数２〜６のアルキレンオキシド構造基であり、ｂ、ｃ、ｄ、ｅはそれぞれ４≦ｂ≦１０、０≦ｃ≦１０、０≦ｄ≦１０、０≦ｅ≦１０の数である。］
で表される。 [Organic silicon compound (silane coupling agent)]
The polyfunctional epoxy group-containing organosilicon compound of the present invention has the following general formula (1):

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the formula (2), at least two of R are glycidyl groups, and a is a number satisfying 1 ≦ a ≦ 100. And the following general formula (3)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the above formula (2), at least two of R are glycidyl groups, and AO is an alkylene oxide structural group having 2 to 6 carbon atoms. , B, c, d, and e are numbers of 4 ≦ b ≦ 10, 0 ≦ c ≦ 10, 0 ≦ d ≦ 10, and 0 ≦ e ≦ 10, respectively. ]
It is represented by

  In this case, a to e are each independently preferably 1 ≦ a ≦ 40, 4 ≦ b ≦ 8, 0 ≦ c ≦ 8, 0 ≦ d ≦ 8, 0 ≦ e ≦ 8, more preferably 1 ≦ e. The numbers are a ≦ 30, 4 ≦ b ≦ 5, 0 ≦ c ≦ 5, 0 ≦ d ≦ 5, and 0 ≦ e ≦ 5.

  In addition, a is a number of 1 or more as described above, and in the case of 1, it is a glycerin derivative. However, from the viewpoint of increasing the reaction point, a = 2 diglycerin derivative, a = 3 triglycerin derivative, etc. A is a polyglycerin derivative of 2 or more, more preferably 3 or more, and still more preferably 4 or more. In addition, each of c to e is a number of 0 or more, but preferably each is 1 or more, and c + d + e is preferably a number of 0 to 24, more preferably 3 to 24, and still more preferably 3 to 21. It is.

  AO in the formula (3) is an alkylene oxide structural group having 2 to 6 carbon atoms. More specifically, an ethylene oxide structural group (EO), a propylene oxide structural group (PO), a butylene oxide structural group (BO), etc. Can be mentioned. In addition, when c to e are 2 or more, the connecting chain composed of an alkylene oxide structural group may be a polyalkylene oxide structural group composed of EO, PO, or BO alone, or two or more types of alkylene oxide structures. It may be a combination of groups. Further, when c to e are 3 or more and two or more types of alkylene oxide structural groups, the formed polymer chain may be a random polymer or a block polymer.

  Specific examples of R ′ in the formula (2) include a methyl group, an ethyl group, a propyl group, a butyl group, a heptyl group, a hexyl group, and the alkyl group of X includes a methyl group, an ethyl group, and a propyl group. Group, butyl group and the like.

  In the compound of the above formula (1), the functional group ratio of (i) glycidyl group, (ii) alkoxysilyl group or silanol group is 0.02 ≦ (i) / (ii) ≦ 100 as a molar ratio. The range is preferably 0.05, more preferably 0.05 ≦ (i) / (ii) ≦ 50, and particularly preferably 0.1 ≦ (i) / (ii) ≦ 10. When it is smaller than 0.02, the alkoxysilyl group or silanol group is excessive, and it is difficult to synthesize due to the design structure, and there may be a problem in the stability of the obtained product. When it is larger than 100, since the alkoxysilyl group or silanol group is hardly contained, the effect of introducing the alkoxysilyl group or silanol group may be hardly exhibited.

  In the compound of the above formula (3), the functional group ratio of (iii) glycidyl group, (iv) alkoxysilyl group or silanol group is in a range of 0.1 ≦ (iii) / (iv) ≦ 9 as a molar ratio. It is preferable that there is more preferably 0.2 ≦ (iii) / (iv) ≦ 5.

  In these polyfunctional epoxy group-containing organosilicon compounds, some hydroxyl groups in the structure of the polyglycidyl ether compound having a plurality of epoxy groups react with the silane coupling agent to form a bond. Specifically, by using a silane coupling agent having an isocyanate group (hereinafter referred to as isocyanate silane) as the silane coupling agent, a urethane bond is formed between the hydroxyl group and the isocyanate group.

  More specifically, the polyfunctional epoxy group-containing organosilicon compound according to the present invention is, for example, an isocyanate group with a polyglycidyl ether compound having at least two epoxy groups and at least one hydroxyl group in one molecule. By reacting an isocyanate group of a silane coupling agent having a group and at least one alkoxy group or silanol group, at least two epoxy groups, at least one alkoxysilyl group and silanol group are contained in one molecule. It can be obtained as a polyfunctional epoxy group-containing organosilicon compound.

  In this case, when (poly) glycerin polyglycidyl ether is used as the polyglycidyl ether compound having at least two epoxy groups and at least one hydroxyl group in one molecule, the organosilicon compound of the above formula (1) is can get. When a sorbitol-based polyglycidyl ether is used as the polyglycidyl ether compound having at least two epoxy groups and at least one hydroxyl group in one molecule, an organosilicon compound of the above formula (3) is obtained.

（式中、Ｒ¹は水素原子又はグリシジル基を示し、少なくとも１つは水素原子、少なくとも２つはグリシジル基であり、ａは上述した通りの意味を示す。）
で示されるものが挙げられる。なお、（ｖ）グリシジル基、（ｖｉ）水酸基のモル比率（ｖ）／（ｖｉ）は０．０１〜１００が好ましく、より好ましくは０．０２〜５０、更に好ましくは０．１〜４０である。また、そのエポキシ当量は好ましくは１００〜５００、より好ましくは１００〜４００、更に好ましくは１００〜３００である。エポキシ当量が小さすぎると製造が難しくなることがあり、大きすぎるとエポキシ含有率が低くなり、得られる多官能エポキシ基含有有機ケイ素化合物の特性が不十分となることがある。 Here, as the (poly) glycerin polyglycidyl ether, the following formula (4)

(Wherein R ¹ represents a hydrogen atom or a glycidyl group, at least one is a hydrogen atom, at least two are glycidyl groups, and a has the meaning as described above.)
The thing shown by is mentioned. The molar ratio (v) / (vi) of (v) glycidyl group and (vi) hydroxyl group is preferably 0.01 to 100, more preferably 0.02 to 50, still more preferably 0.1 to 40. . The epoxy equivalent is preferably 100 to 500, more preferably 100 to 400, and still more preferably 100 to 300. If the epoxy equivalent is too small, production may be difficult, and if it is too large, the epoxy content may be low, and the resulting polyfunctional epoxy group-containing organosilicon compound may have insufficient properties.

（式中、Ｒ¹は水素原子又はグリシジル基を示し、少なくとも１つは水素原子、少なくとも２つはグリシジル基であり、ＡＯは炭素数２〜６のアルキレンオキシド構造基であり、ｂ、ｃ、ｄ、ｅはそれぞれ４≦ｂ≦１０、０≦ｃ≦１０、０≦ｄ≦１０、０≦ｅ≦１０の数である。）
で示されるものが挙げられる。なお、（ｖｉｉ）グリシジル基、（ｖｉｉｉ）水酸基のモル比率（ｖｉｉ）／（ｖｉｉｉ）は好ましくは０．１〜９、より好ましくは０．２〜５である。また、そのエポキシ当量は１００〜５００が好ましく、より好ましくは１００〜４００、更に好ましくは１００〜３００である。エポキシ当量が小さすぎると製造が難しくなることがあり、大きすぎるとエポキシ含有率が低くなり、得られる多官能エポキシ基含有有機ケイ素化合物の特性が不十分となることがある。 Moreover, as sorbitol type polyglycidyl ether, following formula (5)

(Wherein R ¹ represents a hydrogen atom or a glycidyl group, at least one is a hydrogen atom, at least two are glycidyl groups, AO is an alkylene oxide structural group having 2 to 6 carbon atoms, b, c, d and e are numbers of 4 ≦ b ≦ 10, 0 ≦ c ≦ 10, 0 ≦ d ≦ 10, and 0 ≦ e ≦ 10, respectively.
The thing shown by is mentioned. The molar ratio (vii) / (viii) of (vii) glycidyl group and (viii) hydroxyl group is preferably 0.1-9, more preferably 0.2-5. The epoxy equivalent is preferably 100 to 500, more preferably 100 to 400, and still more preferably 100 to 300. If the epoxy equivalent is too small, production may be difficult, and if it is too large, the epoxy content may be low, and the resulting polyfunctional epoxy group-containing organosilicon compound may have insufficient properties.

  As the polyglycidyl ether compound, (poly) glycerin polyglycidyl ether, sorbitol-based polyglycidyl ether, commercially available products such as SR-4GL manufactured by Sakamoto Pharmaceutical Co., Ltd., Denacol EX- manufactured by Nagase ChemteX Corporation 1310, Denacol EX-1410, Denacol EX-1610, EX-610U, or the like can be used.

  On the other hand, the silane coupling agent for reacting with the polyglycidyl ether compound and introducing a hydrolyzable silyl group into the compound has a functional group that does not react with an epoxy group but selectively reacts with a hydroxyl group. Of these, isocyanate silane is preferred.

  Specific structures of isocyanate silane include 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3-isocyanatepropyldimethylmethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropylmethyldiethoxysilane. , 3-isocyanatopropyldimethylethoxysilane, isocyanatemethyltrimethoxysilane, isocyanatemethylmethyldimethoxysilane, isocyanatemethyldimethylmethoxysilane, isocyanatemethyltriethoxysilane, isocyanatemethylmethyldiethoxysilane, isocyanatemethyldimethylethoxysilane, etc. Among these, 3-isocyanatopropyltriethoxysilane, - isocyanate propyl trimethoxysilane is preferred.

  The reaction ratio between the polyglycidyl ether compound and the isocyanate silane is such that the isocyanate group of the isocyanate silane is 0.01 to 1 mol, particularly 0.1 to 1 mol, relative to 1 mol of the hydroxyl group of the polyglycidyl ether compound. It is preferable to make it.

  The polyfunctional epoxy group-containing organosilicon compound of the present invention can be obtained by reacting a polyglycidyl ether compound and an isocyanate silane, and the reaction temperature at that time is preferably 25 to 90 ° C, more preferably 40 to 80 ° C. is there. When the temperature is lower than 25 ° C., the reaction rate may be low. When the temperature is higher than 90 ° C., side reactions such as transesterification occur between the hydroxyl group of polyglycidyl ether and the alkoxysilyl site of isocyanate silane, and alcohol generation occurs. It can happen. The reaction time is not particularly limited, but is usually 10 minutes to 24 hours.

  As the solvent used when the polyglycidyl ether compound and the isocyanate silane are reacted, any solvent may be used as long as it does not react with the isocyanate group. Specific examples include hydrocarbon solvents, aromatic solvents, ketone solvents, amide solvents, ester solvents, ether solvents, and more specifically, hydrocarbon solvents such as pentane, hexane, heptane, Octane, decane, cyclohexane, etc., aromatic solvents such as benzene, toluene, xylene, etc., ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc., amide solvents such as formamide, dimethylformamide, pyrrolidone, N-methylpyrrolidone, etc. Examples of the ester solvent include ethyl acetate, butyl acetate, and lactone. Examples of the ether solvent include diethyl ether, dibutyl ether, cyclopentyl methyl ether, tetrahydrofuran, and 1,4-dioxane.

When the polyglycidyl ether compound and isocyanate silane are reacted, a catalyst may be used for improving the reaction rate. The catalyst may be one generally used in a urethane reaction. Specifically, a tertiary amine compound, dibutyltin oxide, dioctyltin oxide, tin (II) bis (2-ethylhexanoate), etc. Can be mentioned.
In addition, although the usage-amount of a catalyst is a catalytic amount, it is 0.001-1 mass% normally with respect to the total amount of a polyglycidyl ether compound and isocyanate silane.

  Here, the obtained polyfunctional epoxy group-containing organosilicon compound preferably has a polystyrene-reduced weight average molecular weight of 200 to 10,000, particularly 300 to 8,000, as determined by gel permeation chromatography (GPC). If the molecular weight is too small, production may be difficult, and if it is too large, workability may be deteriorated.

Specific examples of the polyfunctional epoxy group-containing organosilicon compound include the following.
In the formula (1), n = 3, m = 3, a (average) = 9, (i) glycidyl group / (ii) ethoxysilyl group = 3 (molar ratio),
In the formula (1), n = 3, m = 3, a (average) = 9, (i) glycidyl group / (ii) ethoxysilyl group = 6 (molar ratio),
In the formula (1), n = 3, m = 3, a (average) = 9, (i) glycidyl group / (ii) ethoxysilyl group = 0.3 (molar ratio),
In the formula (1), n = 3, m = 3, a (average) = 7, (i) glycidyl group / (ii) ethoxysilyl group = 3 (molar ratio),
In formula (3), n = 3, m = 3, b = 4, c = d = e = 2, alkylene oxide is an ethylene oxide structural group, (iii) glycidyl group / (iv) ethoxysilyl group = 3 (mol) Ratio),
In formula (3), n = 3, m = 3, b = 4, c = d = e = 2, alkylene oxide is a propylene oxide structural group, (iii) glycidyl group / (iv) ethoxysilyl group = 3 (mol) Ratio),
In formula (3), n = 3, m = 3, b = 4, c = d = e = 2, alkylene oxide is a butylene oxide structural group, (iii) glycidyl group / (iv) ethoxysilyl group = 3 (mol) Ratio),
In formula (3), n = 3, m = 3, b = 4, c = d = e = 2, alkylene oxide is a mixture of ethylene oxide structural group and propylene oxide structural group, (iii) glycidyl group / (iv) Ethoxysilyl group = 3 (molar ratio)
In formula (3), n = 3, m = 3, b = 4, c = d = e = 4, alkylene oxide is a mixture of an ethylene oxide structural group and a propylene oxide structural group, and a random polymer of each structural group, (iii) ) Glycidyl group / (iv) ethoxysilyl group = 3 (molar ratio)
In the formula (3), n = 3, m = 3, b = 4, c = d = e = 4, alkylene oxide is a mixture of an ethylene oxide structural group and a propylene oxide structural group, and a block polymer of each structural group, (iii) ) Glycidyl group / (iv) ethoxysilyl group = 3 (molar ratio).

[Adhesive composition]
Next, the pressure-sensitive adhesive composition containing the polyfunctional epoxy group-containing silane coupling agent will be described.
The pressure-sensitive adhesive composition of the present invention is
(A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms; (b) a vinyl monomer containing a crosslinkable functional group and / or (meth) (Meth) acrylic copolymer obtained by copolymerizing 0.1 to 10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) Polyfunctional epoxy group-containing organosilicon compound: 0.01 to 9 parts by mass is contained.

  Here, the (a) (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms used in the composition of the present invention is 90 to 99.9 mass out of 100 mass parts of the monomer to be copolymerized. Part, particularly 91 to 99 parts by weight, and if the content is less than 90 parts by weight, the initial adhesive force may be reduced, and if it exceeds 99.9 parts by weight, the cohesive force is reduced and the durability is decreased. May cause problems.

  The (a) component (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms is other than the (b) component (meth) acrylic monomer containing a crosslinkable functional group. An alkyl ester having 1 to 12 carbon atoms of (meth) acrylic acid can be used, and an alkyl ester having 2 to 8 carbon atoms is more preferable. That is, in the alkyl (meth) acrylate, the cohesive strength of the pressure-sensitive adhesive may be reduced if the alkyl group is in a long chain form. Therefore, the carbon number of the alkyl group is 1 in order to maintain the cohesive strength at high temperatures. The range of -12 is preferable, More preferably, it is the range of 2-8.

  Such (meth) acrylic acid ester monomers include butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) ) Acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, and the like. You may mix and use the above.

  (B) The vinyl monomer and (meth) acrylic monomer containing the crosslinkable functional group of the component react with the crosslinking agent so that the cohesive force of the adhesive is not broken under high temperature or high temperature and high humidity conditions. Provides cohesive strength or adhesive strength due to chemical bonding. Component (b) is used in an amount of 0.1 to 10 parts by weight, particularly 1 to 9 parts by weight, based on 100 parts by weight of the monomer to be copolymerized, and less than 0.1 parts by weight. In some cases, cohesive failure tends to occur under high temperature and high humidity. When the amount exceeds 10 parts by mass, the compatibility is remarkably reduced, surface migration occurs, and the fluidity decreases while the cohesive force increases and stress increases. Mitigation ability may decrease.

  Examples of the vinyl monomer or (meth) acrylic monomer having a crosslinkable functional group as the component (b) include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl ( Monomers containing hydroxyl groups such as (meth) acrylate, diethylene glycol mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, (meth) acrylic acid, (meth) acrylic acid dimer, itaconic acid, maleic acid and maleic anhydride Monomers containing a carboxyl group such as (meth) acryloxypropyltrimethoxysilane, (meth) acryloxypropyltriethoxysilane, (meth) acryloxypropylmethyldimethoxysilane, (meth) acryloxypropylmethyldiethoxysilane, (Me ) Monomers containing hydrolyzable silyl groups such as acryloxymethyltrimethoxysilane, (meth) acryloxymethyltriethoxysilane, (meth) acryloxymethylmethyldimethoxysilane, (meth) acryloxymethylmethyldiethoxysilane, etc. Although it is mentioned, it is not restricted to these. The said monomer can be used individually by 1 type or in mixture of 2 or more types.

  In the present invention, during the production of the acrylic copolymer, other copolymerizable monomers are further used to adjust the glass transition temperature of the pressure-sensitive adhesive composition and to impart other functionality. Can do. Specifically, copolymerizable monomers such as acrylonitrile, styrene, glycidyl (meth) acrylate and vinyl acetate can be used. The blending ratio of these copolymerizable monomers is preferably 0.1 to 9.9 parts by mass, more preferably 0.5 to 8 parts by mass, out of 100 parts by mass of the monomer to be copolymerized.

  The viscoelastic properties of the pressure-sensitive adhesive composition are mainly based on the molecular weight, molecular weight distribution, or molecular structure abundance of the polymer chain, and are particularly determined by the molecular weight. Therefore, the (meth) acrylic copolymer used in the present invention is used. The molecular weight (weight average molecular weight: Mw) of the polymer is preferably 800,000 to 2,000,000, more preferably 900,000 to 1.9 million. The weight average molecular weight is a standard polystyrene equivalent value measured by gel permeation chromatography (GPC). If the molecular weight is too small, the desired viscoelastic properties may not be obtained. If the molecular weight is too large, the viscosity of the polymer becomes very high and handling becomes difficult, which may reduce productivity.

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

  In the pressure-sensitive adhesive composition of the present invention, the polyfunctional crosslinking agent (B) serves to increase the cohesive strength of the pressure-sensitive adhesive by reacting with a carboxyl group, a hydroxyl group, or the like. The content of the crosslinking agent is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the copolymer (A). If the amount is too large, aggregation may be severe, and it may be difficult to form an adhesive sheet or the like. If the amount is too small, the desired effect of improving the cohesive force may not be obtained.

  As the polyfunctional crosslinking agent, an isocyanate-based, epoxy-based, aziridine-based, metal chelate-based crosslinking agent or the like can be used, and among them, the isocyanate-based crosslinking agent is easy to use. Examples of the isocyanate crosslinking agent include tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoform diisocyanate, tetramethylxylene diisocyanate, naphthalene diisocyanate, and a reaction product of these with a polyol such as trimethylol propane (trimethylol propane tri Range isocyanate adducts, etc.).

  Epoxy crosslinking agents include ethylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, N, N, N ′, N′-tetraglycidylethylenediamine, glycerin diglycidyl ether, glycerin triglycidyl ether, polyglycerin polyglycidyl luter. And sorbitol-based polyglycidyl ether.

  Examples of the aziridine-based crosslinking agent include N, N′-toluene-2,4-bis (1-aziridinecarboxide), N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxide), and triethylene. Examples include melamine, bisisoprotaloyl-1- (2-methylaziridine), and tri-1-aziridinylphosphine oxide.

  Examples of the metal chelate-based crosslinking agent include compounds in which a polyvalent metal such as aluminum, iron, zinc, tin, titanium, antimony, magnesium, and vanadium is coordinated to acetylacetone or ethyl acetoacetate.

  The polyfunctional epoxy group-containing organosilicon compound of component (C) is represented by the above general formulas (1) and (3), and by adding this silane coupling agent to the adhesive composition, Reworkability and adhesive strength under high temperature and humidity are greatly improved. The specific structure of the silane coupling agent is as described above, and these can be used alone or in combination of two or more. The blending amount is preferably 0.01 to 9 parts by mass, more preferably 0.1 to 5 parts by mass, and particularly preferably 0 with respect to 100 parts by mass of the (A) (meth) acrylic copolymer. 0.1 to 3 parts by mass. If the content is less than 0.01 parts by mass, the effect of adding silane may not be sufficiently exhibited. If the content exceeds 9 parts by mass, bubbles and detachment may occur due to excessive use, and durability may be reduced.

  When the organosilicon compounds represented by the general formulas (1) and (3) are used in combination, the blending ratio is not particularly limited as long as both components are homogeneously compatible. The organosilicon compound represented by the formula: (3) is preferably from 1: 100 to 100: 1, more preferably from 20:80 to 80:20.

  In the present invention, a tackifying resin can be further added to adjust the adhesive performance. The content can be used in the range of 1 to 100 parts by mass, particularly 5 to 90 parts by mass with respect to 100 parts by mass of the (A) (meth) acrylic copolymer. At this time, if the amount is less than 1 part by mass, the effect of adjustment may be insufficient. If the amount exceeds 100 parts by mass, the regularity or cohesion of the pressure-sensitive adhesive may be reduced.

  Examples of tackifying resins include (hydrogenated) hydrocarbon resins, (hydrogenated) rosin resins, (hydrogenated) rosin ester resins, (hydrogenated) terpene resins, (hydrogenated) terpene phenol resins, polymerized rosins. Resins, polymerized rosin ester resins, and the like can be used, and these can be used alone or in admixture of two or more.

  In addition to the above components, a low molecular weight material such as a plasticizer and a leveling agent, an epoxy resin, a curing agent, and the like can be mixed and used as an additional component as necessary, as long as the object of the present invention is not impaired. Agents, antioxidants, decolorizers, reinforcing agents, fillers, antifoaming agents, surfactants, and the like can be appropriately added and used according to general purposes.

  The production method of the pressure-sensitive adhesive composition of the present invention is not particularly limited, and the above-described (A) (meth) acrylic copolymer, (B) polyfunctional crosslinking agent, and (C) silane coupling agent (polyfunctional epoxy). Group-containing organosilicon compound) is obtained by mixing in a conventional manner. The mixing condition is preferably 10 minutes to 10 hours at 10 to 150 ° C. In this case, the polyfunctional epoxy group-containing organosilicon compound can be added and used in the blending step after the polymerization of the (meth) acrylic copolymer, and the (meth) acrylic copolymer production step Even when added in, the same effect is exhibited. In addition, the polyfunctional cross-linking agent can be uniformly coated when the functional group cross-linking reaction of the cross-linking agent hardly occurs in the blending process for forming the pressure-sensitive adhesive layer obtained by curing the pressure-sensitive adhesive composition. It becomes. After the coating, when a drying and aging process is performed, a crosslinked structure is formed, and an adhesive layer having elasticity and strong cohesion is obtained.

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

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

  In consideration of the optimum physical balance, the crosslink density of the pressure-sensitive adhesive layer is suitably 5 to 95% by mass, particularly 7 to 93% by mass. The cross-linking density refers to a value obtained by mass% of the amount of a portion where a cross-linked structure that is not dissolved in a solvent is formed by a generally known method for measuring the gel content of an adhesive. At this time, when the cross-linking density of the pressure-sensitive adhesive layer is less than 5% by mass, the cohesive force of the pressure-sensitive adhesive layer is lowered, and there is a possibility that problems of adhesion durability such as bubbles or peeling may occur. When it exceeds, it may not be attached tightly and durability may be weakened.

[Adhesive polarizing plate]
Next, a pressure-sensitive adhesive polarizing plate including a pressure-sensitive adhesive layer obtained by applying and curing the pressure-sensitive adhesive composition on one side or both sides of a polarizing film or the like will be described.
The pressure-sensitive adhesive polarizing plate of the present invention has a polarizing film or polarizing element, and a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition on one or both sides of the polarizing film or polarizing element. It does not specifically limit about the polarizing film or polarizing element which comprises a polarizing plate. Examples of the polarizing film include a film obtained by stretching a film made of a polyvinyl alcohol resin containing a polarizing component such as iodine or a heterochromatic dye, and the thickness of these polarizing films is not limited. , Can be molded to a normal thickness.

  Examples of the polyvinyl alcohol resin include polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, and a saponified product of an ethylene / vinyl acetate copolymer.

  Moreover, on both surfaces of the polarizing film having an adhesive layer, a cellulose film such as triacetyl cellulose, a polyester film such as a polycarbonate film and a polyethylene terephthalate film, a polyethersulfone film, polyethylene, polypropylene, and a copolymer thereof. A multilayer film or the like on which a protective film such as a polyolefin-based film is laminated can be formed. At this time, the thickness of these protective films is not particularly limited, and can be formed to a normal thickness.

  In the present invention, the method for forming the pressure-sensitive adhesive layer on the polarizing film is not particularly limited, and the pressure-sensitive adhesive composition is directly applied to the surface of the polarizing film using a bar coater and dried. A method of applying the composition to the surface of the peelable substrate and drying it, and then transferring the pressure-sensitive adhesive layer formed on the surface of the peelable substrate to the surface of the polarizing film and then aging can be employed. . In this case, drying is preferably 25 to 150 ° C. and 20 to 90% RH for 5 minutes to 5 hours, and aging is preferably 25 to 150 ° C. and 20 to 90% RH for 5 minutes to 5 hours.

  The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is usually preferably 0.01 to 100 μm, more preferably 0.1 to 50 μm. When the thickness of the pressure-sensitive adhesive layer is smaller than the above range, the effect as the pressure-sensitive adhesive layer may be insufficient, and when the thickness is larger than the above range, the effect of the pressure-sensitive adhesive layer may be saturated and the cost may be increased.

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

[Liquid Crystal Display]
The adhesive polarizing plate of the present invention is particularly applicable to general liquid crystal display devices in general, and the type of the liquid crystal panel is not particularly limited. In particular, it is preferable to configure a liquid crystal display device including a liquid crystal panel in which the adhesive polarizing plate of the present invention is bonded to one or both sides of a liquid crystal cell in which liquid crystal is sealed between a pair of glass substrates.

  In addition to the polarizing film described above, the pressure-sensitive adhesive composition of the present invention is an industrial sheet, particularly a reflective sheet, a structural pressure-sensitive adhesive sheet, a photographic pressure-sensitive adhesive sheet, a lane display pressure-sensitive adhesive sheet, an optical pressure-sensitive adhesive product, and an electronic component. Can be used for any purpose. Further, the present invention can also be applied to application fields having the same concept of action, such as laminate products having a multi-layer structure, that is, general commercial adhesive sheet products, medical patches, and heating activations.

  The pressure-sensitive adhesive composition of the present invention is a (meth) acrylic pressure-sensitive adhesive containing a silane coupling agent having a coordinating functional group, and has excellent reworkability because it has a low initial adhesive force when attached to glass or the like. , Adhesive strength after wet heat treatment after pasting becomes sufficiently high and excellent in long-term durability.

  EXAMPLES Hereinafter, although a synthesis example, an Example, and a comparative example are shown and this invention is demonstrated in more detail, this invention is not limited to these Examples. In the following examples, the viscosity, specific gravity, and refractive index are values measured at 25 ° C. NMR stands for nuclear magnetic resonance spectroscopy, IR stands for infrared spectroscopy, and GPC stands for gel permeation chromatography. The viscosity is based on measurement at 25 ° C. with a capillary kinematic viscometer.

[Synthesis Example 1]
A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 100 g of polyglycerin polyglycidyl ether (SR-4GL, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) having an epoxy equivalent of 168 and heated to 80 ° C. . Into this, 49.0 g of 3-isocyanatopropyltriethoxysilane was added dropwise and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid and had a weight average molecular weight of 1800, a viscosity of 1074 mPa · s, and an epoxy equivalent of 265. In formula (1), n is 3, m is 3, a is 9 on average, and the functional group molar ratio (i) glycidyl group / (ii) ethoxysilyl group = 3. FIG. 1 shows an IR spectrum of the compound before the reaction, FIG. 2 shows an IR spectrum in the middle of the reaction, and FIG.

[Synthesis Example 2]
In a 1 L separable flask equipped with a stirrer, a reflux condenser, a dropping funnel and a thermometer, 100 g of polyglycerin polyglycidyl ether (SR-4GL, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) with an epoxy equivalent of 168, and 0.6 g of dioctyltin oxide are added. Charged and heated to 80 ° C. Into this, 49.0 g of 3-isocyanatopropyltriethoxysilane was added dropwise, and the mixture was heated and stirred at 80 ° C. for 2 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid and had a weight average molecular weight of 1800, a viscosity of 1014 mPa · s, and an epoxy equivalent of 267. In the formula (1), n is 3, m is 3, a is 9 on average, and the functional group molar ratio (i) glycidyl group / (ii) ethoxysilyl group = 3.

[Synthesis Example 3]
A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 100 g of polyglycerin polyglycidyl ether (SR-4GL, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) having an epoxy equivalent of 168 and heated to 80 ° C. . Into this, 24.5 g of 3-isocyanatopropyltriethoxysilane was dropped and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid, and had a weight average molecular weight of 1700, a viscosity of 1184 mPa · s, and an epoxy equivalent of 219. In the formula (1), n was 3, m was 3, a was 9 on average, and the functional group molar ratio (i) glycidyl group / (ii) ethoxysilyl group = 6.

[Synthesis Example 4]
A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 100 g of polyglycerin polyglycidyl ether (SR-4GL, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) having an epoxy equivalent of 168 and heated to 80 ° C. . Into this, 441.0 g of 3-isocyanatopropyltriethoxysilane was added dropwise and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid and had a weight average molecular weight of 2500, a viscosity of 1374 mPa · s, and an epoxy equivalent of 910. In the formula (1), n is 3, m is 3, a is 9 on average, and the functional group molar ratio (i) glycidyl group / (ii) ethoxysilyl group = 0.3. It was.

[Synthesis Example 5]
A 1 L separable flask equipped with a stirrer, a reflux condenser, a dropping funnel and a thermometer was charged with 100 g of polyglycerin polyglycidyl ether having an epoxy equivalent of 172 (Denacol EX-1310, manufactured by Nagase ChemteX Corporation) and heated to 80 ° C. did. Into this, 49.7 g of 3-isocyanatopropyltriethoxysilane was dropped and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid and had a weight average molecular weight of 1870, a viscosity of 108 mPa · s, and an epoxy equivalent of 259. In formula (1), n is 3, m is 3, a is 7 on average, and the functional group molar ratio (i) glycidyl group / (ii) ethoxysilyl group = 3.

[Synthesis Example 6]
A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 100 g of polyglycerin polyglycidyl ether (Denacol EX-1410, manufactured by Nagase ChemteX Corporation) having an epoxy equivalent of 172 and heated to 80 ° C. did. Into this, 52.2 g of 3-isocyanatopropyltriethoxysilane was dropped and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid and had a weight average molecular weight of 1700, a viscosity of 200 mPa · s, and an epoxy equivalent of 247. In formula (1), n is 3, m is 3, a is 7 on average, and the functional group molar ratio (i) glycidyl group / (ii) ethoxysilyl group = 3.

[Synthesis Example 7]
A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 100 g of sorbitol-based polyglycidyl ether (Denacol EX-1610, manufactured by Nagase ChemteX Corporation) having an epoxy equivalent of 172 and heated to 80 ° C. did. Into this, 49.9 g of 3-isocyanatopropyltriethoxysilane was dropped, and the mixture was heated and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid and had a weight average molecular weight of 3800, a viscosity of 1421 mPa · s, and an epoxy equivalent of 261. In formula (3), n is 3, m is 3, b is 4, AO is an ethylene oxide group, c, d, and e are 2, and the functional group molar ratio (iii) glycidyl Group / (iv) ethoxysilyl group = 3.

[Synthesis Example 8]
A 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 100 g of sorbitol-based polyglycidyl ether (Denacol EX-610U, manufactured by Nagase ChemteX Corporation) having an epoxy equivalent of 220 and heated to 80 ° C. did. 39.8 g of 3-isocyanatopropyltriethoxysilane was added dropwise thereto, and the mixture was heated and stirred at 80 ° C. for 4 hours. Thereafter, it was confirmed by IR measurement that the absorption peak derived from the isocyanate group of the raw material had completely disappeared and an absorption peak derived from the urethane bond was generated instead, and the reaction was terminated. The obtained reaction product was a pale yellow liquid, and had a weight average molecular weight of 3600, a viscosity of 1114 mPa · s, and an epoxy equivalent of 315. In formula (3), n is 3, m is 3, b is 4, AO is a propylene oxide group, c, d, and e are 2, and the functional group molar ratio (iii) glycidyl Group / (iv) ethoxysilyl group = 3.

[Synthesis Example 9]
In a 1 L separable flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer, 98.1 g of n-butyl acrylate (BA), 0.6 g of acrylic acid (AA), 2-hydroxyethyl methacrylate (2-HEMA) ) 1.3 g was charged, and 100 g of ethyl acetate was charged as a solvent and dissolved. Thereafter, nitrogen gas bubbling was performed for 1 hour to remove oxygen, and the reaction system was purged with nitrogen and maintained at 62 ° C. Into this, 0.03 g of azobisisobutyronitrile as a polymerization initiator was added while stirring and reacted at 62 ° C. for 8 hours to obtain a (meth) acrylic copolymer as a base polymer.

[Examples 1 to 8]
Trimethylolpropane tolylene diisocyanate adduct (TDI) as a crosslinking agent and silane coupling agent obtained in Synthesis Examples 1 to 8 with respect to 100 parts by mass of the (meth) acrylic copolymer obtained in Synthesis Example 9 Were mixed in the composition shown in Table 1 to prepare an adhesive composition.

  After the obtained pressure-sensitive adhesive composition was coated on a release paper and dried, a uniform pressure-sensitive adhesive layer of 25 μm was obtained. The pressure-sensitive adhesive layer produced in this way was subjected to pressure-sensitive adhesive processing on an iodine-type polarizing plate having a thickness of 185 μm, and then the obtained polarizing plate was cut into an appropriate size and used for each evaluation.

  About the test piece of the manufactured polarizing plate, it evaluated about the change of adhesive force on durability, glass adhesiveness, rework property, heat resistance, or heat-and-moisture resistance conditions through the evaluation test method shown below, and the result is shown in Tables 2-4. Indicated.

[Comparative Examples 1-5]
The same method as in the above examples except that the silane coupling agents A-1 to A-4 shown in Table 1 are used instead of the silane coupling agent of the present invention, and the silane coupling agent is not added. The pressure-sensitive adhesive was blended and manufactured, and the laminating process was carried out. The obtained test pieces were also evaluated in the same manner as in Examples, and the results are shown in Tables 2 to 4.

In Table 1, abbreviations are as follows.
TDI: cross-linking agent, tolylene diisocyanate adduct of trimethylolpropane

シランＡ−２：γ−グリシドキシプロピルトリメトキシシラン（信越化学工業（株）製 ＫＢＭ−４０３）
シランＡ−３：γ−イソシアネートプロピルトリエトキシシラン（信越化学工業（株）製 ＫＢＥ−９００７）
シランＡ−４：両末端アルコキシシリル変性ＰＯ型ポリエーテル化合物（カネカ（株）製サイリルＳＡＴ１０） Silane A-1:

Silane A-2: γ-glycidoxypropyltrimethoxysilane (KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd.)
Silane A-3: γ-isocyanatopropyltriethoxysilane (KBE-9007 manufactured by Shin-Etsu Chemical Co., Ltd.)
Silane A-4: Both-end alkoxysilyl-modified PO type polyether compound (Silane SAT10 manufactured by Kaneka Corporation)

Evaluation test <durability>
A polarizing plate (90 mm × 170 mm) coated with an adhesive was attached to a glass substrate (110 mm × 190 mm × 0.7 mm) with the optical absorption axes crossed on both sides. At this time, the applied pressure was about 5 kgf / cm ³ , and the work was performed in a clean room so that bubbles and foreign matters were not generated.

  In order to evaluate the moisture resistance and heat resistance characteristics of this test piece, after leaving it for 1000 hours under the condition of 60 ° C./90% relative humidity, the presence or absence of generation of bubbles or peeling was confirmed. Regarding heat resistance, after standing for 1000 hours at 80 ° C./30% relative humidity, bubbles and peeling were observed. In addition, before evaluating the state of a test piece, it left still at room temperature (25 degreeC) for 24 hours. The results are shown in Table 2.

Evaluation criteria for durability evaluation are as follows.
○: No bubbles or exfoliation phenomenon △: Some bubbles or exfoliation phenomena x: Many bubbles or exfoliation phenomena

<Glass adhesive strength, adhesive strength change under high temperature and high temperature and humidity conditions>
After the polarizing plate coated with the adhesive was aged for 7 days at room temperature (23 ° C./60% RH), the polarizing plate was cut into 1 inch × 6 inch size, and a 2 kg rubber roller was used. Affixed to a non-alkali glass having a thickness of 0.7 mm. After storing at room temperature, the initial adhesive force was measured after 1 hour, then aged at 50 ° C. for 4 hours, and then stored at room temperature for 1 hour, and then the adhesive force was measured. The results are shown in Table 2.

Also, in order to see the degree of increase in adhesive strength under high temperature and high temperature and humidity conditions, after aging according to time under the conditions of 60 ° C / 30% RH and 60 ° C / 90% RH, respectively, it is allowed to cool at room temperature for 1 hour. The adhesive strength was measured. The results are shown in Tables 3 and 4.
At this time, a tensile tester was used to measure the adhesive strength, and the peel strength was measured at a speed of 300 mm / min and an angle of 180 °.

<Reworkability>
After a polarizing plate (90 mm × 170 mm) coated with a pressure-sensitive adhesive was attached to a glass substrate (110 mm × 190 mm × 0.7 mm), it was aged at room temperature for 1 hour (initial adhesive force) and 50 ° C. × 4 hours, After allowing to cool at room temperature for 1 hour, the polarizing plate was peeled off from the glass. The results are shown in Table 2.
The evaluation criteria for reworkability are as follows.
○: Removable easily △: Removable slightly difficult ×: Unpeelable, glass breakage

  Regarding polarizing plates to which the adhesives of Examples and Comparative Examples were applied, the evaluation results on durability, glass adhesion, reworkability, changes in adhesion at high temperature and high temperature and humidity obtained through the previous evaluation method The results are shown in Tables 2 to 4 below.

  The above results show that the composition of the present invention is excellent in initial reworkability, exhibits sufficient adhesive strength with glass by high-temperature and high-temperature and high-humidity treatment, and has a long-term durability. It proves that.

Claims (9)

(A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and (b) a vinyl monomer and / or (meta ) (Meth) acrylic copolymer obtained by copolymerizing 0.1-10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) The following general formula (1)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the formula (2), at least two of R are glycidyl groups, and a is a number satisfying 1 ≦ a ≦ 100. ]
A pressure-sensitive adhesive composition comprising 0.01 to 9 parts by mass of a polyfunctional epoxy group-containing organosilicon compound represented by : (A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and (b) a vinyl monomer and / or (meta ) (Meth) acrylic copolymer obtained by copolymerizing 0.1-10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) The following general formula (3)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the above formula (2), at least two of R are glycidyl groups, and AO is an alkylene oxide structural group having 2 to 6 carbon atoms. , B, c, d, and e are numbers of 4 ≦ b ≦ 10, 0 ≦ c ≦ 10, 0 ≦ d ≦ 10, and 0 ≦ e ≦ 10, respectively. ]
A pressure-sensitive adhesive composition comprising 0.01 to 9 parts by mass of a polyfunctional epoxy group-containing organosilicon compound represented by : (A) (a) 90 to 99.9 parts by mass of a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms, and (b) a vinyl monomer and / or (meta ) (Meth) acrylic copolymer obtained by copolymerizing 0.1-10 parts by mass of acrylic monomer: 100 parts by mass,
(B) Multifunctional crosslinking agent: 0.01 to 10 parts by mass,
(C) The following general formula (1)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the formula (2), at least two of R are glycidyl groups, and a is a number satisfying 1 ≦ a ≦ 100. ]
And a polyfunctional epoxy group-containing organosilicon compound represented by the following general formula (3)

[Wherein, R represents a hydrogen atom, a glycidyl group, and the following formula (2)

(In the formula, R 'represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 10. is there.)
Wherein at least one of R is a group of the above formula (2), at least two of R are glycidyl groups, and AO is an alkylene oxide structural group having 2 to 6 carbon atoms. , B, c, d, and e are numbers of 4 ≦ b ≦ 10, 0 ≦ c ≦ 10, 0 ≦ d ≦ 10, and 0 ≦ e ≦ 10, respectively. ]
A pressure-sensitive adhesive composition comprising 0.01 to 9 parts by mass of a polyfunctional epoxy group-containing organosilicon compound represented by : (B) A vinyl monomer or (meth) acrylic monomer containing a crosslinkable functional group is 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, diethylene glycol Mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, (meth) acryloxypropyltrimethoxysilane, (meth) acryloxypropyltriethoxysilane, (meth) acryloxypropylmethyldimethoxysilane, (meth) acryloxy Propylmethyldiethoxysilane, (meth) acryloxymethyltrimethoxysilane, (meth) acryloxymethyltriethoxysilane, (meth) acryloxymethylmethyldimethoxysilane, (meth) acryloxymethyl Methyl diethoxy silane, (meth) acrylic acid, (meth) acrylic acid dimer, any of claims 1 to 3 itaconic acid, one or more monomers selected from the group consisting of maleic acid and maleic anhydride one wherein the pressure-sensitive adhesive composition. (B) a polyfunctional crosslinking agent, an isocyanate compound, an epoxy compound, any one of claims 1 to 4 is one or more crosslinking agents selected from the group consisting of aziridine compounds and metal chelate compound The pressure-sensitive adhesive composition described. The pressure-sensitive adhesive composition according to any one of claims 1 to 5 crosslink density of the cured product is 5 to 95 mass%. A pressure-sensitive polarizing plate comprising a polarizing film and a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition according to any one of claims 1 to 6 on one side or both sides of the polarizing film. Furthermore, the adhesive polarizing plate of Claim 7 which has 1 or more types of layers selected from the group which consists of a protective layer, a reflection layer, a phase difference plate, a light viewing angle compensation film, and a brightness enhancement film. 9. A liquid crystal comprising a liquid crystal panel having a liquid crystal cell in which liquid crystal is sealed between a pair of glass substrates, and the adhesive polarizing plate according to claim 7 or 8 attached to one or both surfaces of the liquid crystal cell. Display device.

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