JP5436493B2 - Adhesive composition, optical member and adhesive sheet - Google Patents

Description

  The present invention relates to a pressure-sensitive adhesive composition, an optical member, and a pressure-sensitive adhesive sheet. More particularly, the present invention relates to a pressure-sensitive adhesive composition having a long pot life and excellent workability, and reaching practical pressure-sensitive adhesive performance in a short aging time after pressure-sensitive adhesive processing. Moreover, it is related with an optical member and an adhesive sheet provided with this adhesive composition.

  Recently, the use of flat panel displays (FPD) such as liquid crystal display devices (LCD), plasma displays (PDP), and organic EL devices has been expanded. In connection with this, improvement of workability | operativity and productivity of the adhesive used for FPD is calculated | required.

  Patent Document 1 discloses an optical film pressure-sensitive adhesive composition containing an acrylic polymer and a titanium coupling agent and / or a zirconium coupling agent. With this configuration, it is disclosed that the pressure-sensitive adhesive composition for an optical film is excellent in durability and light leakage even under high temperature and high temperature and high humidity conditions.

  Further, Patent Document 2 discloses a pressure-sensitive adhesive composition for a surface protective film for an optical member, which contains an isocyanate compound and an organic titanium oxide compound in an acrylic polymer. With such a configuration, it is disclosed that the pressure-sensitive adhesive composition for a surface protective film for optical members has a curing period and physical properties equivalent to those when an organic tin compound is used as a curing catalyst for an isocyanate compound.

JP 2010-65102 A JP 2010-217227 A

  However, the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition described in Patent Documents 1 and 2 requires a long aging time of 1 day or more until the practical pressure-sensitive adhesive performance is reached after the crosslinking treatment, and the productivity is low. There was a problem.

  The present invention has been made in view of the above circumstances, and has an object to provide a pressure-sensitive adhesive composition having a long pot life, excellent workability, reaching practical adhesive performance in a short aging time, and excellent productivity. To do.

  Another object of the present invention is to provide an optical member and an adhesive sheet containing such an adhesive composition.

  The present inventors have intensively studied to solve the above problems.

  As a result, the pressure-sensitive adhesive composition containing a specific (meth) acrylic copolymer, a carbodiimide crosslinking agent, and a titanium coupling agent, a zirconium coupling agent, or a hafnium coupling agent in a specific composition has a long pot life. It was found that it was excellent in workability, reached practical adhesive performance in a short aging time of 0.5 days after adhesive processing, and productivity was greatly improved, and the present invention was completed.

  That is, the present invention includes 0.1 to 9 parts by mass of a carboxyl group-containing monomer (a-1), 0 to 1 part by mass of a hydroxy group-containing (meth) acrylic monomer (a-2), and 99.9 to 90. Consists of parts by mass of (meth) acrylic acid ester monomer (a-3) (however, the total amount of carboxyl group-containing monomer, hydroxy group-containing (meth) acrylic monomer, and (meth) acrylic acid ester monomer is 100 parts by mass) And (100) part by weight of (meth) acrylic copolymer (A) having a monomer component and a weight average molecular weight of 100,000 to 2,000,000, and 100 parts by weight of (meth) acrylic copolymer (A). In contrast, 0.05 to 5 parts by mass of a carbodiimide crosslinking agent (B), a titanium coupling agent, a zirconium coupling agent or a hafnium coupling agent (C) It is an adhesive composition containing 0.01-0.3 mass part.

  Moreover, the other invention of this invention is an optical member or an adhesive sheet containing such an adhesive composition.

  The pressure-sensitive adhesive composition of the present invention has a long pot life and excellent workability, and reaches a practical pressure-sensitive adhesive performance in a short ripening time after pressure-sensitive adhesive processing, thereby greatly improving productivity.

  Therefore, the pressure-sensitive adhesive composition of the present invention is effective for adhesion of various adherends, and the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition of the present invention is particularly suitable as a pressure-sensitive adhesive layer for optical members and pressure-sensitive adhesive sheets. Can be used for

  The present invention includes 0.1 to 9 parts by weight of a carboxyl group-containing monomer (a-1), 0 to 1 part by weight of a hydroxy group-containing (meth) acrylic monomer (a-2), and 99.9 to 90 parts by weight. (Meth) acrylic acid ester monomer (a-3) (however, the total amount of carboxyl group-containing monomer, hydroxy group-containing (meth) acrylic monomer, and (meth) acrylic acid ester monomer is 100 parts by mass) 100 parts by weight of (meth) acrylic copolymer (A) containing a monomer component and having a weight average molecular weight of 100,000 to 2,000,000, and 100 parts by weight of (meth) acrylic copolymer (A) , 0.05 to 5 parts by mass of a carbodiimide crosslinking agent (B), a titanium coupling agent, a zirconium coupling agent or a hafnium coupling agent (C) 0.01 Including 0.3 parts by mass, and a pressure-sensitive adhesive composition.

  The pressure-sensitive adhesive composition of the present invention uses a specific (meth) acrylic copolymer (A), contains a carbodiimide crosslinking agent as a crosslinking agent, and further contains a titanium-based, zirconium-based or hafnium-based coupling agent. Features.

  By using a specific (meth) acrylic copolymer (A) in combination with a carbodiimide cross-linking agent and a titanium coupling agent, zirconium coupling agent or hafnium coupling agent, the pot property is not affected. A pressure-sensitive adhesive composition having both a long life and a substantially improved workability and productivity in which the pressure-sensitive adhesive layer is crosslinked (cured) in a short aging time after the pressure-sensitive adhesive processing is obtained.

  In addition, the pressure-sensitive adhesive layer formed using the pressure-sensitive adhesive composition of the present invention has an appropriate pressure-sensitive adhesive strength and adhesion to a substrate as a pressure-sensitive adhesive for optical members, and further suppresses / prevents metal corrosion. Excellent resistance, light leakage resistance, durability, adherend contamination resistance, low-temperature stability, and reworkability.

  Furthermore, the pressure-sensitive adhesive layer formed using the pressure-sensitive adhesive composition of the present invention has an appropriate pressure-sensitive adhesive strength and adhesion to a substrate as a pressure-sensitive adhesive for pressure-sensitive adhesive sheets, and further suppresses / prevents metal corrosion. Excellent in resistance, adherend contamination resistance, low-temperature stability, transparency, heat resistance, and moist heat resistance.

  Hereinafter, each component of the pressure-sensitive adhesive composition of the present invention will be described in detail.

  In the present specification, “(meth) acrylate” is a general term for acrylate and methacrylate. Similarly, a compound containing (meth) such as (meth) acrylic acid is a general term for a compound having “meta” in the name and a compound not having “meta”. For this reason, “(meth) acryl” includes both acrylic and methacrylic. “(Meth) acrylate” includes both acrylate and methacrylate. “(Meth) acrylic acid” includes both acrylic acid and methacrylic acid.

(A) (Meth) acrylic copolymer The (meth) acrylic copolymer used in the present invention (hereinafter also simply referred to as “component (A)”) is 0.1 to 9 parts by weight of a carboxyl group-containing monomer ( a-1), 0 to 1 part by mass of a hydroxy group-containing (meth) acrylic monomer (a-2), and 99.9 to 90 parts by mass of a (meth) acrylic acid ester monomer (a-3) Contains body components. In addition, the total amount of a carboxyl group-containing monomer, a hydroxy group-containing (meth) acrylic monomer, and a (meth) acrylic acid ester monomer is 100 parts by mass. And the weight average molecular weight of this (meth) acryl copolymer is 100,000-2 million.

(A-1) Carboxyl Group-Containing Monomer The carboxyl group-containing monomer according to the present invention (hereinafter also simply referred to as “component (a-1)”) is an unsaturated monomer having at least one carboxyl group in the molecule. . Specific examples of the carboxyl group-containing monomer include, but are not limited to, (meth) acrylic acid, maleic acid, maleic anhydride, fumaric acid, fumaric anhydride, crotonic acid, itaconic acid, itaconic anhydride, myristoleic acid, Examples include palmitoleic acid and oleic acid. These may be used alone or in combination of two or more.

  Of these, (meth) acrylic acid, maleic acid, maleic anhydride, fumaric acid, fumaric anhydride, crotonic acid, itaconic acid, and itaconic anhydride are preferred, and (meth) acrylic acid is more preferred.

  In this invention, the usage-amount of a carboxyl group-containing monomer is 0.1-9 mass parts. When the amount used exceeds 9 parts by mass, the carboxyl group in the copolymer (A) becomes excessive, and the crosslinking point formed by the reaction between the carboxyl group and the carbodiimide crosslinking agent (B) becomes excessive. The flexibility of the pressure-sensitive adhesive composition of the invention is reduced, and the light leakage resistance and durability of the pressure-sensitive adhesive layer are reduced (adhesion does not occur). On the other hand, when the amount used is less than 0.1 parts by mass, the crosslinking with the carbodiimide crosslinking agent (B) becomes insufficient and the heat resistance is lowered.

(A-2) Hydroxy group-containing (meth) acrylic monomer The hydroxy group-containing (meth) acrylic monomer according to the present invention (hereinafter also simply referred to as “component (a-2)”) is an acrylic having a hydroxy group in the molecule. Monomer. Specific examples of the hydroxy group-containing (meth) acrylic monomer include, but are not limited to, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, Pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, neopentyl glycol mono (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolethane di (meth) acrylate, 2-hydroxypropyl (meth) ) Acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, N-2-hydroxy Examples include til (meth) acrylamide, cyclohexanedimethanol monoacrylate, and further obtained by addition reaction of glycidyl group-containing compounds such as alkyl glycidyl ether, allyl glycidyl ether, glycidyl (meth) acrylate, and (meth) acrylic acid. And the like. These may be used alone or in combination of two or more.

  Among these, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, N-2-hydroxyethyl (meth) acrylamide, and cyclohexanedimethanol monoacrylate are preferable, and 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and N-2-hydroxyethyl (meth) acrylamide are more preferred.

  The usage-amount of a hydroxyl-group-containing acrylic monomer is 0-1 mass part. When the amount used exceeds 1 part by mass, the hydroxy group in the copolymer (A) becomes excessive, and the crosslinking point formed by the reaction between the hydroxy group and the carbodiimide crosslinking agent (B) becomes excessive. The flexibility of the pressure-sensitive adhesive composition of the invention is reduced, and the light leakage resistance and durability of the pressure-sensitive adhesive layer are reduced (the possibility of gelation is increased).

(A-3) (meth) acrylic acid ester monomer (meth) acrylic acid ester monomer (hereinafter also simply referred to as “component (a-3)”) is a (meth) acrylic acid having no hydroxy group in the molecule. Ester. Specific examples of the (meth) acrylic acid ester monomer include, but are not limited to, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate. , Isobutyl (meth) acrylate, tert-butyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, tert-octyl (meth) ) Acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate , Phenyl (meth) acrylate, benzyl (meth) acrylate, dodecyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, cyclohexyl (meth) acrylate, 4-n-butylcyclohexyl (meth) acrylate, 2-ethylhexyl diglycol ( (Meth) acrylate, butoxyethyl (meth) acrylate, butoxymethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 2- (2-methoxyethoxy) ethyl (meth) acrylate, 2- (2-butoxyethoxy) ethyl (Meth) acrylate, 4-butylphenyl (meth) acrylate, phenyl (meth) acrylate, 2,4,5-tetramethylphenyl (meth) acrylate, phenoxymethyl (meth) acrylate, Xylethyl (meth) acrylate, polyethylene oxide monoalkyl ether (meth) acrylate, polyethylene oxide monoalkyl ether (meth) acrylate, polypropylene oxide monoalkyl ether (meth) acrylate, trifluoroethyl (meth) acrylate, pentadecafluorooxyethyl ( Examples include meth) acrylate, 2-chloroethyl (meth) acrylate, 2,3-dibromopropyl (meth) acrylate, and tribromophenyl (meth) acrylate. These may be used alone or in combination of two or more.

  Among these, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are preferable, and methyl (meth) acrylate, n-butyl (meth) acrylate, 2- Ethylhexyl (meth) acrylate is more preferred.

The usage-amount of a (meth) acrylic acid ester monomer (a-3) is 99.9-90 mass parts. When the amount used exceeds 99.9 parts by mass, the component (a-1) is relatively decreased, crosslinking with the carbodiimide crosslinking agent (B) is insufficient, and heat resistance is lowered.
On the other hand, when the amount used is less than 90 parts by mass, the amount of the component (a-1) is relatively increased, and adhesiveness does not appear for the same reason as described above.

  The production method of the (meth) acrylic copolymer (A) is not particularly limited, and is a solution polymerization method using a polymerization initiator, an emulsion polymerization method, a suspension polymerization method, a reverse phase suspension polymerization method, a thin film polymerization method, Conventionally known methods such as spray polymerization can be used. Examples of the polymerization control method include adiabatic polymerization, temperature controlled polymerization, and isothermal polymerization. In addition to the method of initiating polymerization with a polymerization initiator, a method of initiating polymerization by irradiating with radiation, electron beam, ultraviolet rays or the like can also be employed. Among these, the solution polymerization method using a polymerization initiator is preferable because the molecular weight can be easily adjusted and impurities can be reduced. For example, using ethyl acetate, toluene, methyl ethyl ketone or the like as a solvent, and preferably adding 0.01 to 0.50 parts by weight of a polymerization initiator with respect to 100 parts by weight of the total amount of monomers, It is obtained by reacting at a reaction temperature of 60 to 90 ° C. for 3 to 10 hours. Examples of the polymerization initiator include azo compounds such as azobisisobutyronitrile (AIBN), 2,2′-azobis (2-methylbutyronitrile), azobiscyanovaleric acid; tert-butyl peroxypivalate, organic peroxides such as tert-butylperoxybenzoate, tert-butylperoxy-2-ethylhexanoate, di-tert-butyl peroxide, cumene hydroperoxide, benzoyl peroxide, tert-butyl hydroperoxide; Examples thereof include inorganic peroxides such as hydrogen peroxide, ammonium persulfate, potassium persulfate, and sodium persulfate. These may be used alone or in combination of two or more.

  If necessary, other monomers copolymerizable with the components (a-1) to (a-3) are used. Other monomers are not particularly limited, and specific examples include acrylic monomers having an epoxy group such as glycidyl (meth) acrylate and methylglycidyl (meth) acrylate; dimethylaminoethyl (meth) acrylate, diethylaminoethyl ( Acrylic monomers having amino groups such as (meth) acrylate, N-tert-butylaminoethyl (meth) acrylate, methacryloxyethyltrimethylammonium chloride (meth) acrylate; (meth) acrylamide, N-methylol (meth) acrylamide, N- Acrylic monomers having an amide group such as methoxymethyl (meth) acrylamide, N, N-methylenebis (meth) acrylamide; 2-methacryloyloxyethyl diphenyl phosphate (meth) a Acrylic monomers having a phosphate group such as relate, trimethacryloyloxyethyl phosphate (meth) acrylate, triacryloyloxyethyl phosphate (meth) acrylate; sulfopropyl (meth) acrylate sodium, 2-sulfoethyl (meth) acrylate sodium, 2- Acrylic monomer having a sulfonic acid group such as sodium acrylamido-2-methylpropanesulfonate; Acrylic monomer having a urethane group such as urethane (meth) acrylate; p-tert-butylphenyl (meth) acrylate, o-biphenyl (meth) Acrylic vinyl monomers having a phenyl group such as acrylate; 2-acetoacetoxyethyl (meth) acrylate, vinyltrimethoxysilane, vinyltriethoxysilane, Vinyl monomers having a silane group such as nitrotris (β-methoxyethyl) silane, vinyltriacetylsilane, methacryloyloxypropyltrimethoxysilane; styrene, chlorostyrene, α-methylstyrene, vinyltoluene, vinyl chloride, vinyl acetate, vinyl propionate , Acrylonitrile, vinyl pyridine and the like. These other monomers may be used alone or in combination of two or more.

  Among these other monomers, (meth) acrylamide, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 2-acetoacetoxyethyl (meth) acrylate and vinyl acetate are preferred, and (meth) acrylamide and vinyl acetate are preferred. More preferred.

  The amount of other monomers used is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of components (a-1) to (a-3). It is more preferably ˜7 parts by mass, and further preferably 0.3 to 6 parts by mass.

  The weight average molecular weight (Mw) of the (meth) acrylic copolymer (A) obtained by copolymerizing the above components is 100,000 to 2,000,000. When the weight average molecular weight is less than 100,000, the heat resistance is insufficient. On the other hand, when the weight average molecular weight exceeds 2 million, the tack is low and the bonding property is lowered. In addition, in this specification, the weight average molecular weight shall employ | adopt the value of polystyrene conversion measured by the method as described in an Example.

  The total amount of component (a-1), component (a-2), and component (a-3) is 100 parts by mass.

  The component (A) may be used alone or in combination of two or more polymers.

(B) Carbodiimide crosslinking agent In addition to the component (A), the pressure-sensitive adhesive composition of the present invention contains a carbodiimide crosslinking agent (hereinafter, also simply referred to as “component (B)”). The carbodiimide crosslinking agent reacts and bonds with the hydroxy group and / or carboxyl group in the (meth) acrylic copolymer (A) to form a crosslinked structure.

  The carbodiimide crosslinking agent (B) used in the present invention is not particularly limited. Specifically, for example, a compound having two or more carbodiimide groups (—N═C═N—) in the molecule is preferably used, and a known polycarbodiimide can be used.

  Moreover, as a carbodiimide compound, the high molecular weight polycarbodiimide produced | generated by carrying out the decarboxylation condensation reaction of diisocyanate in presence of a carbodiimidization catalyst can also be used.

  Examples of such compounds include those obtained by subjecting the following diisocyanates to a decarboxylation condensation reaction.

  As the diisocyanate, 4,4′-diphenylmethane diisocyanate, 3,3′-dimethoxy-4,4′-diphenylmethane diisocyanate, 3,3′-dimethyl-4,4′-diphenylmethane diisocyanate, 4,4′-diphenyl ether diisocyanate, 3,3′-dimethyl-4,4′-diphenyl ether diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1-methoxyphenyl-2,4-diisocyanate, isophorone diisocyanate, 4,4′- One of dicyclohexylmethane diisocyanate and tetramethylxylylene diisocyanate, or a mixture of two or more thereof can be used.

  As the carbodiimidization catalyst, 1-phenyl-2-phospholene-1-oxide, 3-methyl-2-phospholene-1-oxide, 1-ethyl-3-methyl-2-phospholene-1-oxide, 1-ethyl- Phosphorene oxides such as 2-phospholene-1-oxide or their 3-phospholene isomers can be used.

  Such a high molecular weight polycarbodiimide may be synthesized or a commercially available product may be used.

  Examples of commercially available components (B) include Carbodilite (registered trademark) series manufactured by Nisshinbo Chemical Co., Ltd. Among these, Carbodilite (registered trademark) V-01, V-03, V-05, V-07, and V-09 are preferable because of excellent compatibility with organic solvents.

  The compounding quantity of a component (B) is 0.05-5 mass parts with respect to 100 mass parts of components (A). If it exists in this range, a moderate crosslinked structure can be formed and the outstanding heat resistance can further be achieved. When the blending amount of the carbodiimide crosslinking agent (B) is less than 0.05 parts by mass, a sufficient crosslinked structure cannot be formed and heat resistance is lowered. On the other hand, when the amount exceeds 5 parts by mass, the crosslinking reaction proceeds excessively, the adhesive strength is reduced, and it becomes impossible to follow the shrinkage of the polarizing plate over time, and the light leakage resistance and durability are lowered.

  The said component (B) may be used independently and may be used in combination of 2 or more type.

(C) Titanium coupling agent, zirconium coupling agent or hafnium coupling agent The pressure-sensitive adhesive composition of the present invention comprises a titanium coupling agent, zirconium coupling agent or hafnium coupling agent (hereinafter simply referred to as “component (C)”). Also called). By including such a component (C), productivity is improved by improving the curing accelerating effect without inhibiting the physical properties of the adhesive. The titanium coupling agent, zirconium coupling agent or hafnium coupling agent used in the present invention (hereinafter also simply referred to as “the coupling agent of the present invention” or “group 4 coupling agent of the periodic table”) is a titanium atom, It is not particularly limited as long as it is a compound containing a zirconium atom or a hafnium atom and improving the curing accelerating effect with respect to the pressure-sensitive adhesive composition of the present invention, and can be selected by referring to or combining conventionally known knowledge. it can. For example, a coupling agent as disclosed in JP-T-2003-519631, JP-A-2005-108499, or JP-A-2009-292731 can be used by appropriately selecting. Moreover, you may use a commercial item.

  The inventors have:

A coupling agent manufactured by Ajinomoto Fine Techno Co., Ltd.

It has been found that a coupling agent manufactured by Kenrich Petrochemicals Co., Ltd. can improve the effect of promoting the curing with respect to the pressure-sensitive adhesive composition of the present invention. The mechanism by which the intended object of the present invention can be achieved by including a titanium coupling agent, a zirconium coupling agent or a hafnium coupling agent in the pressure-sensitive adhesive composition is not necessarily clear, but the titanium atom, zirconium It is considered that atoms and hafnium atoms promote hydrogen abstraction of the carboxyl group, and that the carboxyl group and the carbodiimide crosslinking agent can be rapidly crosslinked. The reason why the coupling agent of the present invention is better than other metal coupling agents is that the number of ligands of titanium, zirconium and hafnium and the molecular structure (balance between bulkiness and molecular weight) are carboxyl. This is considered to promote hydrogen abstraction of the group. However, in consideration of the effect of hydrogen abstraction, it may be preferable not to contain sulfur or amine. Of course, the technical scope of the present invention is not limited by the above mechanism.

  The compounding quantity of a component (C) is 0.01-0.3 mass part with respect to 100 mass parts of a component (A). Within this range, it is possible to obtain a pressure-sensitive adhesive composition and an optical member having a high crosslinking rate without affecting the physical properties of the pressure-sensitive adhesive. Thus, by adding a titanium coupling agent, a zirconium coupling agent or a hafnium coupling agent containing an element of Group 4 of the periodic table to the pressure-sensitive adhesive as a curing accelerator for the carbodiimide-based curing agent, the remarkable effect of the present invention can be obtained. Can play. When the blending amount of the component (C) is less than 0.01 parts by mass, a sufficient curing accelerating effect cannot be obtained, and a long aging time is required after the adhesive processing. On the other hand, when it exceeds 0.3 parts by mass, light leakage resistance, durability, adhesion to a substrate, low temperature stability, and reworkability are deteriorated. Moreover, it leads to adherend contamination.

  The said component (C) may be used independently and may be used in combination of 2 or more type.

(D) Isocyanate cross-linking agent The pressure-sensitive adhesive composition of the present invention may contain an isocyanate cross-linking agent (D) (hereinafter also simply referred to as “component (D)”). By adding an isocyanate crosslinking agent (D), durability of the obtained adhesive layer can be improved more. Moreover, light resistance improves significantly.

  The component (D) used in the present invention is not particularly limited. Specifically, for example, triallyl isocyanate, dimer acid diisocyanate, 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), 4,4′- Diphenylmethane diisocyanate (4,4′-MDI), 2,4′-diphenylmethane diisocyanate (2,4′-MDI), 1,4-phenylene diisocyanate, xylylene diisocyanate (XDI), tetramethylxylidene diisocyanate (TMXDI), Aromatic diisocyanates such as tolidine diisocyanate (TODI) and 1,5-naphthalene diisocyanate (NDI); hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), lysine diisocyanate Aliphatic diisocyanates such as norbornane diisocyanate methyl (NBDI); transcyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), H6-XDI (hydrogenated XDI), H12-MDI (hydrogenated MDI), etc. Alicyclic diisocyanates; carbodiimide-modified diisocyanates of the above diisocyanates; or their isocyanurate-modified diisocyanates.

  Moreover, the adduct body of said isocyanate compound and polyol compounds, such as a trimethylol propane, the biuret body and isocyanurate body of these isocyanate compounds can also be used conveniently.

  The component (D) may be synthesized or a commercially available product may be used. Examples of commercially available components (D) include Coronate (registered trademark) L, Coronate (registered trademark) HL, Coronate (registered trademark) HX, Coronate (registered trademark) 2030, Coronate (registered trademark) 2031 (and above, Japan). Polyurethane Industry Co., Ltd.), Takenate (registered trademark) D-102, Takenate (registered trademark) D-110N, Takenate (registered trademark) D-200, Takenate (registered trademark) D-202 (above, manufactured by Mitsui Chemicals, Inc.) ), Duranate ™ 24A-100, Duranate ™ TPA-100, Duranate ™ TKA-100, Duranate ™ P301-75E, Duranate ™ E402-90T, Duranate ™ E405-80T, Duranate (trademark) TSE-100, Duranate (trademark) -101, Duranate (trademark) D-201 (above, manufactured by Asahi Kasei Chemicals Corporation), Sumijour (registered trademark) N-75, N-3200, N-3300 (above, Sumika Bayer Urethane Co., Ltd.) and the like. It is done.

  Among these components (D), Coronate (registered trademark) L, Coronate (registered trademark) HL, Coronate (registered trademark) HX, Takenate (registered trademark) D110N, Duranate (trademark) 24A-100, Duranate (trademark) TPA- 100 is preferable, and Coronate (registered trademark) L, Coronate (registered trademark) HX, and Duranate (registered trademark) 24A-100 are more preferable.

  In addition, these components (D) may be used independently and may be used in combination of 2 or more types.

  It is preferable that the usage-amount in the case of using a component (D) is 0.05-5 mass parts with respect to 100 mass parts of components (A). If it is this range, the adhesive composition of this invention may have the outstanding durability. The blending amount is more preferably 0.08 to 4 parts by mass, and still more preferably 0.1 to 3 parts by mass.

(E) Silane Coupling Agent The pressure-sensitive adhesive composition of the present invention may contain a silane coupling agent (hereinafter also simply referred to as “component (E)”). By using a silane coupling agent, the reactivity is improved, and the mechanical strength and adhesive strength of the crosslinked product can be improved. Such a silane coupling agent is not particularly limited. Specifically, for example, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, n-propyltrimethoxysilane, ethyltrimethoxysilane, diethyldiethoxysilane, n-butyltrimethoxysilane, n-hexyltriethoxysilane , N-octyltrimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, cyclohexylmethyldimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropiyl Triethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane , Γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptop Pills methyl dimethoxy silane, bis - (3- [triethoxysilyl] propyl) tetrasulfide, .gamma. isocyanatepropyltriethoxysilane and the like. Further, a silane coupling agent having a functional group such as an epoxy group (glycidoxy group), an amino group, a mercapto group, or a (meth) acryloyl group, and a functional group having reactivity with these functional groups. A compound having a hydrolyzable silyl group obtained by reacting an agent, another coupling agent, polyisocyanate and the like with each functional group in an arbitrary ratio can also be used.

  Moreover, you may use a silane coupling agent oligomer as a component (E). In the silane coupling agent oligomer, at least one silane compound having at least an alkoxy group is condensed to form a —Si—O—Si— structure, and at least one alkoxy group is bonded to the silicon atom. It is a compound having an organic functional group in the molecule.

  Examples of the organic functional group include a vinyl group, an epoxy group, a styryl group, a (meth) acryloyl group, a methacryloxy group, an acryloxy group, an amino group, a ureido group, a chloropropyl group, a mercapto group, and a polysulfide group. Among these, an epoxy group, a mercapto group, and a (meth) acryloyl group are preferable, and an epoxy group and a mercapto group are particularly preferable in order to achieve both improvement in durability of the resulting pressure-sensitive adhesive layer and realization of low adhesiveness.

  As the silane coupling agent oligomer, a dimer having 2 silicon atoms in one molecule to about 100 silicon atoms in one molecule, that is, having an average polymerization degree of 2 to 100 can be used. . When the average degree of polymerization increases, the viscosity of the silane coupling agent oligomer increases, and it may become a paste or a solid, which makes handling difficult. Therefore, the average degree of polymerization is preferably 2 to 80, more preferably 3 to 50.

  The organic functional group contained in the silane coupling agent oligomer is usually bonded to a silicon atom via a suitable linking group. Examples of the linking group include alkylene groups such as methylene group, ethylene group, trimethylene group, hexamethylene group and decamethylene group, divalent hydrocarbon groups having an aromatic ring such as methylphenylethyl group, methoxymethyl group and methoxy group. Examples thereof include a divalent aliphatic group having an oxygen atom between them, such as an ethyl group and a methoxypropyl group. When the organic functional group is an epoxy group, the functional group may be formed between two adjacent carbon atoms constituting the ring.

  The silane coupling agent oligomer may be, for example, a co-oligomer obtained by partial cohydrolysis polycondensation of a silane compound represented by the following chemical formula 2 and tetraalkoxysilane.

In the chemical formula 2, R ⁴ and R ⁵ each independently represents an alkyl group or a phenyl group, X represents an organic group having a mercapto group, an epoxy group, or a (meth) acryloyloxy group, and Y represents Represents an alkyl group, an alkoxy group, a phenyl group, a phenoxy group, an aralkyl group or an aralkyloxy group.

In the above chemical formula, the alkyl group represented by R ⁴ and R ⁵ has, for example, 1 to 10 carbon atoms. In particular, compounds in which R ⁴ and R ⁵ are each independently a methyl group or an ethyl group are preferably used.

  Specific examples of the organic functional group represented by X include, for example, mercaptomethyl group, 3-mercaptopropyl group, 6-mercaptohexyl group, 10-mercaptodecyl group, 2- (4-mercaptomethylphenyl) ethyl group, Glycidoxymethyl group, 3-glycidoxypropyl group, 2- (3,4-epoxycyclohexyl) ethyl group, acryloyloxymethyl group, 3-acryloyloxypropyl group, methacryloyloxymethyl group, 3-methacryloyloxypropyl group Etc.

  The alkyl group and alkoxy group represented by Y preferably have 1 to 10 carbon atoms, and the aralkyl and aralkyloxy groups preferably have 7 to 10 carbon atoms.

  Specific examples of the functional group-containing silane compound represented by the chemical formula 2 include, for example, mercaptomethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 2- (4-mercaptomethylphenyl). ) Ethyltrimethoxysilane, 6-mercaptohexyltrimethoxysilane, 10-mercaptodecyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, glycidoxymethyltrimethoxysilane, 3-glycyl Sidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, acryloyloxymethyltrimethoxysilane, -Acryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltriethoxysilane, methacryloyloxymethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltributoxysilane , 3-acryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and the like.

  In the tetraalkoxysilane partially cohydrolyzed and polycondensed with the functional group-containing silane compound represented by the chemical formula 2, the four alkoxy groups bonded to the silicon atom preferably have 1 to 10 carbon atoms. The four alkoxy groups bonded to the silicon atom may all be the same, or different alkoxy groups may be bonded to the silicon atom. From the viewpoint of ease of production or availability, compounds in which the same alkoxy group is bonded to a silicon atom are preferred, and specific examples include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane. It is done.

In the case where a silane coupling agent oligomer is formed by partial cohydrolysis polycondensation of the functional group-containing silane compound represented by Chemical Formula 2 and tetraalkoxysilane, in Formula 2 above, -OR ⁴ bonded to a silicon atom and A silanol group formed by partial hydrolysis of an alkoxysilyl group or phenoxysilyl group of —OR ⁵ and a silanol group formed by partial hydrolysis of an alkoxysilyl group in tetraalkoxysilane are condensed. Thus, it becomes a silane coupling agent oligomer. Such an oligomer is preferable because the pressure-sensitive adhesive composition tends to be difficult to scatter in the pressure-sensitive adhesive coating and drying step.

  When the silane coupling agent oligomer that can be used in the present invention is shown by a combination of monomers, for example, the following can be mentioned.

  Mercaptomethyl trimethoxysilane-tetramethoxysilane co-oligomer, mercaptomethyltrimethoxysilane-tetraethoxysilane co-oligomer, mercaptomethyltriethoxysilane-tetramethoxysilane co-oligomer, mercaptomethyltriethoxysilane -Tetraethoxysilane co-oligomer etc. are mentioned.

  As a mercaptopropyl group-containing co-oligomer, 3-mercaptopropyltrimethoxysilane-tetramethoxysilane co-oligomer, 3-mercaptopropyltrimethoxysilane-tetraethoxysilane co-oligomer, 3-mercaptopropyl triethoxysilane-tetramethoxysilane co-oligomer , 3-mercaptopropyltriethoxysilane-tetraethoxysilane co-oligomer and the like.

  As glycidoxymethyl group-containing co-oligomers, glycidoxymethyltrimethoxysilane-tetramethoxysilane co-oligomer, glycidoxymethyltrimethoxysilane-tetraethoxysilane co-oligomer, glycidoxymethyltriethoxysilane-tetramethoxysilane Examples include co-oligomers and glycidoxymethyltriethoxysilane-tetraethoxysilane co-oligomers.

  Examples of co-oligomers containing glycidoxypropyl groups include 3-glycidoxypropyltrimethoxysilane-tetramethoxysilane co-oligomer, 3-glycidoxypropyltrimethoxysilane-tetraethoxysilane co-oligomer, 3-glycidoxypropyl tri-oligomer. Examples include ethoxysilane-tetramethoxysilane co-oligomer, 3-glycidoxypropyltriethoxysilane-tetraethoxysilane co-oligomer, and the like.

  As a co-oligomer containing methacryloyloxypropyl group, 3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane co-oligomer, 3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane co-oligomer, 3-acryloyloxypropyltriethoxysilane-tetra Methoxysilane co-oligomer, 3-acryloyloxypropyltriethoxysilane-tetraethoxysilane co-oligomer, 3-acryloyloxypropylmethyldimethoxysilane-tetramethoxysilane co-oligomer, 3-acryloyloxypropylmethyldimethoxysilane-tetraethoxysilane co-oligomer, 3-acryloyloxypropylmethyldiethoxysilane-tetramethoxysilane co-oligomer, 3-acryloyl Co-oligomers containing acryloyloxypropyl groups, such as yloxypropylmethyldiethoxysilane-tetraethoxysilane co-oligomer, 3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane co-oligomer, 3-methacryloyloxypropyltrimethoxysilane-tetra Ethoxysilane co-oligomer, 3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane co-oligomer, 3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane co-oligomer, 3-methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane co-oligomer, 3-methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane co-oligomer, 3-methacryl Acryloyloxy propyl methyl diethoxy silane - tetramethoxysilane co-oligomer, 3-methacryloyloxypropyl diethoxysilane - tetraethoxysilane co-oligomer, and the like.

  The silane coupling agent may be synthesized or a commercially available product may be used. Examples of commercially available silane coupling agents include KBM-303, KBM-403, KBE-402, KBE-403, KBE-502, KBE-503, KBM-5103, KBM-573, KBM-802, and KBM-. 803, KBE-846, KBE-9007 (manufactured by Shin-Etsu Chemical Co., Ltd.); X-41-1805 which is a silane coupling agent oligomer having a mercapto group, a methoxy group and an ethoxy group, a mercapto group, a methyl group and methoxy X-41-1810 which is a silane coupling agent oligomer having a group, X-41-1053 which is a silane coupling agent oligomer having an epoxy group, a methoxy group and an ethoxy group, a silicone having an epoxy group, a methyl group and a methoxy group X-41-1058 which is a silane coupling agent (All trade names, both Shin-Etsu Chemical Co., Ltd.) can be mentioned.

  Among these silane coupling agents, KBM-303, KBM-403, KBE-402, KBE-403, KBM-5103, KBM-573, KBM-802, KBM-803, KBE-846, KBE-9007, X- 41-1805 and X-41-1810 are preferable, and KBM-403 and X-41-1810 are more preferable. In addition, the said silane coupling agent may be used independently and may be used in combination of 2 or more type.

  In the present invention, the amount of the silane coupling agent used is not particularly limited. Specifically, the amount used in the case of using the silane coupling agent (E) is preferably 0.03 to 1 part by mass, more preferably 0.05 to 100 parts by mass with respect to 100 parts by mass of the component (A). 0.5 parts by mass, more preferably 0.1 to 0.3 parts by mass. If it exists in this range, the outstanding heat resistance and adhesiveness can be exhibited.

(F) Additive The pressure-sensitive adhesive composition of the present invention may contain an imidazole compound as an additive. The imidazole compound is considered to play a role of a so-called crosslinking (curing) accelerator for the carbodiimide crosslinking agent, reaches a practical adhesive property in a short aging time, and is excellent in productivity.

  The imidazole compound that can be used in the present invention is preferably represented by the following chemical formula 1.

In Formula 1, R ¹ , R ² , and R ³ are each independently a hydrogen atom, a halogen atom, or a substituted or unsubstituted linear or branched chain having 1 to 10 carbon atoms. It is an alkyl group.

  As an example of the said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom is mentioned, for example.

  Examples of the linear or branched alkyl group having 1 to 10 carbon atoms include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, iso-amyl group, tert-pentyl group, neopentyl group, n-hexyl group, 3-methylpentan-2-yl group, 3-methylpentan-3-yl group, 4 -Methylpentyl group, 4-methylpentan-2-yl group, 1,3-dimethylbutyl group, 3,3-dimethylbutyl group, 3,3-dimethylbutan-2-yl group, n-heptyl group, 1- Methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 1-ethylpentyl group, 1- (n-propyl) butyl group, 1,1-dimethylpentyl group, 1 4-dimethylpentyl group, 1,1-diethylpropyl group, 1,3,3-trimethylbutyl group, 1-ethyl-2,2-dimethylpropyl group, n-octyl group, 2-ethylhexyl group, 2-methylhexane -2-yl group, 2,4-dimethylpentan-3-yl group, 1,1-dimethylpentan-1-yl group, 2,2-dimethylhexane-3-yl group, 2,3-dimethylhexane-2 -Yl group, 2,5-dimethylhexane-2-yl group, 2,5-dimethylhexane-3-yl group, 3,4-dimethylhexane-3-yl group, 3,5-dimethylhexane-3-yl Group, 1-methylheptyl group, 2-methylheptyl group, 5-methylheptyl group, 2-methylheptan-2-yl group, 3-methylheptan-3-yl group, 4-methylheptan-3-yl group, 4- Tylheptan-4-yl group, 1-ethylhexyl group, 2-ethylhexyl group, 1-propylpentyl group, 2-propylpentyl group, 1,1-dimethylhexyl group, 1,4-dimethylhexyl group, 1,5-dimethyl Hexyl group, 1-ethyl-1-methylpentyl group, 1-ethyl-4-methylpentyl group, 1,1,4-trimethylpentyl group, 2,4,4-trimethylpentyl group, 1-isopropyl-1,2 -Dimethylpropyl group, 1,1,3,3-tetramethylbutyl group, n-nonyl group, 1-methyloctyl group, 6-methyloctyl group, 1-ethylheptyl group, 1- (n-butyl) pentyl group 4-methyl-1- (n-propyl) pentyl group, 1,5,5-trimethylhexyl group, 1,1,5-trimethylhexyl group, 2-methyloctane-3 -Yl group, n-decyl group, 1-methylnonyl group, 1-ethyloctyl group, 1- (n-butyl) hexyl group, 1,1-dimethyloctyl group, 3,7-dimethyloctyl group and the like.

  The alkyl group may be substituted with another substituent.

  Examples of substituents include, for example, halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom; alkyl groups such as methyl group, ethyl group, tert-butyl group and dodecyl group; phenyl group and p-tolyl group , Xylyl group, cumenyl group, naphthyl group, anthryl group, phenanthryl group and other aryl groups; methoxy group, ethoxy group, tert-butoxy group and other alkoxy groups; phenoxy group, p-tolyloxy group and other aryloxy groups; Groups, butoxycarbonyl groups, octyloxycarbonyl groups, phenoxycarbonyl, and other alkoxycarbonyl groups; acetoxy groups, propionyloxy groups, methacryloyloxy groups, benzoyloxy groups, and other acyloxy groups; acetyl groups, benzoyl groups, isobutyryl groups, acryloyl groups Acyl groups such as methacryloyl group and methoxalyl group; alkylamino groups such as methylamino group and cyclohexylamino group; dialkylamino groups such as dimethylamino group, diethylamino group, morpholino group and piperidino group; phenylamino group, p-tolylamino group and the like In addition to the arylamino group, hydroxy group, carboxy group, formyl group, amino group, nitro group, cyano group, trifluoromethyl group, trichloromethyl group and the like can be mentioned.

  Furthermore, specific examples of the imidazole compound include, for example, imidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole, 1-ethylimidazole, 2-ethylimidazole, 4-ethylimidazole, 1-propylimidazole. 2-propylimidazole, 4-propylimidazole, 1-butylimidazole, 2-butylimidazole, 4-butylimidazole, 1-pentylimidazole, 2-pentylimidazole, 4-pentylimidazole, 1-hexylimidazole, 2-hexylimidazole 4-hexylimidazole, 1-heptylimidazole, 2-heptylimidazole, 4-heptylimidazole, 1-octylimidazole, 2-octylimidazole, 4-octylimid Sol, 1-nonylimidazole, 2-nonylimidazole, 4-nonylimidazole, 1-decylimidazole, 2-decylimidazole, 4-decylimidazole, 1,2-dimethylimidazole, 1,2-diethylimidazole, 1-ethyl- 2-methylimidazole, 2-ethyl-4-methylimidazole, 1,4-dimethylimidazole, 1,5-dimethylimidazole, 1,2,4-trimethylimidazole, 1,4-dimethyl-2-ethylimidazole, 2- Examples include fluoroimidazole, 4-fluoroimidazole, 2-bromoimidazole, 4-bromoimidazole, 2-iodoimidazole, and 4-iodoimidazole.

Among these imidazole compounds, a compound in which at least one of R ¹ , R ² , and R ^{3 is} a linear or branched alkyl group having 1 to 10 carbon atoms is preferable from the viewpoint of productivity and price. -Methylimidazole, 1-ethylimidazole, 1-propylimidazole, 1-butylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole are more preferred.

  It is preferable that the compounding quantity of an imidazole compound is 0.008-0.2 mass part with respect to 100 mass parts of component (A). Within such a range, a sufficient curing accelerating effect can be obtained, and a long aging time after the adhesion processing can be significantly shortened. The blending amount is more preferably 0.009 to 0.18 parts by mass, and still more preferably 0.01 to 0.15 parts by mass.

  The said imidazole compound may be used independently and may be used in combination of 2 or more type.

  Moreover, a commercial item may be used for the said imidazole compound, and a synthetic item may be used.

  Furthermore, the pressure-sensitive adhesive composition of the present invention includes, as additives, a curing accelerator, an ionic liquid, a lithium salt, an inorganic filler, a softening agent, an antioxidant, an anti-aging agent, a stabilizer, a tackifying resin, and a modification. Resin (polyol resin, phenol resin, acrylic resin, polyester resin, polyolefin resin, epoxy resin, epoxidized polybutadiene resin, etc.), leveling agent, antifoaming agent, plasticizer, dye, pigment (colored pigment, extender pigment, etc.), treatment An additive such as an agent, an ultraviolet blocking agent, a fluorescent brightening agent, a dispersant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, an antistatic agent, a lubricant and a solvent may be contained. Among these, examples of the curing accelerator include dibutyltin dilaurate, JCS-50 (manufactured by Johoku Chemical Industry Co., Ltd.), formate TK-1 (manufactured by Mitsui Chemicals, Inc.) and the like. Examples of the ionic liquid include phosphonium ion, pyridinium ion, pyrrolidinium ion, imidazolium ion, guanidinium ion, ammonium ion, isouronium ion, thiouronium ion, piperidinium ion, pyrazolium ion, sulfonium ion, and the like. Cation component and halogen ion, nitrate ion, sulfate ion, phosphate ion, perchlorate ion, thiocyanate ion, thiosulfate ion, sulfite ion, tetrafluoroborate ion, hexafluorophosphate ion, formate ion, oxalate ion, acetate ion And anionic components such as trifluoroacetate ions and alkyl sulfonate ions. Examples of the antioxidant include dibutylhydroxytoluene (BHT), Irganox (registered trademark) 1010, Irganox (registered trademark) 1035FF, Irganox (registered trademark) 565 (all manufactured by BASF Japan Ltd.) and the like. Can be mentioned. Examples of the tackifying resin include rosins such as rosin acid, polymerized rosin acid and rosin acid ester, terpene resin, terpene phenol resin, aromatic hydrocarbon resin, aliphatic saturated hydrocarbon resin and petroleum resin. Although the usage-amount of an additive in the case of using the said additive is not restrict | limited in particular, For example, it is 0.1-20 mass parts with respect to 100 mass parts of component (A).

  The pressure-sensitive adhesive composition of the present invention can be prepared by mixing the above-described components all together, mixing each component sequentially, or mixing any plural components and then mixing the remaining components. It can manufacture by stirring so that it may become a uniform mixture. More specifically, it can be prepared by heating, for example, at a temperature of 20 to 40 ° C., if necessary, and stirring with a stirrer or the like until it becomes uniform, for example, for 5 minutes to 5 hours.

  The viscosity of the pressure-sensitive adhesive composition of the present invention is not particularly limited. However, considering the ease of coating and the ease of controlling the thickness of the pressure-sensitive adhesive layer formed from the composition, immediately after preparation at 25 ° C. (10 minutes after mixing each component for a predetermined time) The viscosity is preferably 300 to 7000 mPa · s. For example, when used as an adhesive for an optical member, the viscosity immediately after preparation at 25 ° C. (within 10 minutes after mixing each component for a predetermined time) is more preferably 2000 to 6000 mPa · s, and further preferably 2500 to 5000 mPa · s. s. For example, when used as an adhesive for an adhesive sheet, the viscosity immediately after preparation at 25 ° C. (within 10 minutes after mixing each component for a predetermined time) is more preferably 350 to 6800 mPa · s, more preferably 400 to 6500 mPa · s. s. The pressure-sensitive adhesive composition of the present invention has an excellent pot life because an excessive increase in viscosity and gelation of the pressure-sensitive adhesive composition after preparation of the composition are suppressed.

  The pot life can be evaluated by comparing the viscosity of the composition immediately after preparing the pressure-sensitive adhesive composition with the viscosity of the composition after 12 hours from the preparation. That is, it is preferable that the composition after 12 hours from the preparation does not gel, and the viscosity of the composition after 12 hours from the preparation is relative to the viscosity of the composition immediately after preparing the adhesive composition. More preferably, the increase is within 30%. If it is such a range, it will become an adhesive composition which has the outstanding workability | operativity.

  In the present specification, “immediately after” means within 10 minutes. That is, the “viscosity of the composition immediately after preparing the pressure-sensitive adhesive composition” means the viscosity measured within 10 minutes after the preparation of the pressure-sensitive adhesive composition is completed (each component is mixed for a predetermined time).

  The pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition of the present invention is obtained by crosslinking the pressure-sensitive adhesive composition as described above. At that time, the pressure-sensitive adhesive composition is generally crosslinked after application of the pressure-sensitive adhesive composition, but it is also possible to transfer a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition after crosslinking to a substrate or the like. is there. The crosslinking of the pressure-sensitive adhesive composition is usually carried out under conditions of a temperature of 70 to 140 ° C. and preferably for 1 to 5 minutes.

  The pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition of the present invention reaches practical pressure-sensitive adhesive performance in a short period of 0.5 days after pressure-sensitive adhesive processing (after cross-linking). Practical adhesion performance of the pressure-sensitive adhesive layer is determined by the gel fraction after standing for 0.5 days in an atmosphere of 23 ° C. and 50% RH after adhesion processing (after crosslinking treatment) and 23 after adhesion processing (after crosslinking treatment). It can be evaluated by comparing the gel fraction after being allowed to stand for 7 days in an atmosphere of 50 ° C. and 50% RH. That is, the gel fraction after standing for 7 days is preferably the gel fraction after standing for 0.5 days ± 5%, and the gel fraction after standing for 0.5 days ± 3% Is more preferable. If it is such a range, it will become an adhesive composition in which productivity improved significantly. As the gel fraction, a value measured by the method described in Examples described later is adopted.

  The pressure-sensitive adhesive composition of the present invention can be used for bonding various substrates. Examples of the substrate that can be used here include glass, plastic film, paper, and metal foil.

  Examples of the glass include general inorganic glass. Examples of the plastic in the plastic film include polyvinyl chloride resin, polyvinylidene chloride, cellulose resin, acrylic resin, cycloolefin resin, amorphous polyolefin resin, polyethylene, polypropylene, polystyrene, ABS resin, polyamide, and polyester. , Polycarbonate, polyurethane, polyvinyl alcohol, ethylene-vinyl acetate copolymer and chlorinated polypropylene. The amorphous polyolefin-based resin usually has a polymerization unit of a cyclic polyolefin such as norbornene or a polycyclic norbornene-based monomer, and may be a copolymer of a cyclic olefin and a chain cyclic olefin.

  Commercially available non-crystalline polyolefin resins such as Arton from JSR Corporation, ZEONEX (registered trademark) from ZEON Corporation, ZEONOR (registered trademark), APO from Mitsui Chemicals, Apel (registered trademark), etc. There is. In order to form an amorphous polyolefin-based resin into a film, a known method such as a solvent casting method or a melt extrusion method is appropriately used. Examples of the paper include imitation paper, high-quality paper, craft paper, art coat paper, caster coat paper, pure white roll paper, parchment paper, water resistant paper, glassine paper, and corrugated paper. For example, aluminum foil etc. can be mentioned.

  Therefore, this invention also provides an optical member and an adhesive sheet provided with the adhesive layer formed from the adhesive composition of this invention.

  Hereinafter, although these uses are demonstrated in detail, the use of the adhesive composition of this invention is not limited to these uses at all.

<Optical member>
The pressure-sensitive adhesive composition of the present invention may be used by directly applying to one side or both sides of an optical member to form a pressure-sensitive adhesive layer, or by previously forming a pressure-sensitive adhesive layer on a release film. It may be used by transferring to one side or both sides. That is, this invention provides an optical member provided with the adhesive layer formed from the adhesive composition of this invention.

  Preferred examples of the optical member of the present invention include a polarizing plate, a retardation plate, an optical film for plasma display, and a conductive film for touch panel. Among these, the adhesive composition of this invention is excellent in the adhesiveness of a polarizing plate and glass. Of course, the present invention is not limited to the above-described form, and can be used for bonding other members.

  When using the adhesive composition of this invention for the adhesive layer of an optical member, the component (A) contained in a composition is 0.1-9 mass parts carboxyl group containing monomer (a-1), 0-1. It preferably contains a monomer component composed of a hydroxy group-containing (meth) acrylic monomer (a-2) by mass part and 99.9 to 90 parts by mass of a (meth) acrylic acid ester monomer (a-3), The weight average molecular weight is preferably 1 million to 2 million. The total amount of component (a-1), component (a-2) and component (a-3) is 100 parts by mass.

  The amount of the component (a-1) used in the component (A) in the optical member application is more preferably 0.1 to 9 parts by mass, still more preferably 0.3 to 5 parts by mass, It is particularly preferably 5 to 3 parts by mass.

  Further, the amount of the component (a-2) used in the component (A) in the optical member application is more preferably 0 to 1 part by mass, further preferably 0 to 0.5 part by mass. It is especially preferable that it is -0.3 mass part.

  Furthermore, the usage-amount of the component (a-3) in the component (A) in an optical member use is more preferably 99.9-90 mass parts, and it is 99.7-94.5 mass parts. More preferably, it is 99.5-96.7 mass parts.

  The total amount of the component (a-1) and component (a-2) used in the component (A) in the optical member application is preferably 0.1 to 10 parts by mass, and 0.3 It is more preferable that it is -5.5 mass parts, and it is still more preferable that it is 0.5-3.3 mass parts.

  As for the weight average molecular weight of the component (A) in an optical member use, it is more preferable that it is 1,000,000-1,800,000, and it is further more preferable that it is 1.1 million-1,700,000.

  Moreover, it is preferable that content of the component (B) in the adhesive composition for optical member uses is 0.05-5 mass parts with respect to 100 mass parts of components (A), 0.1-5 More preferably, it is part by mass.

  Moreover, it is preferable that content of a component (C) is 0.01-0.3 mass part with respect to 100 mass parts of components (A), and it is 0.02-0.2 mass part. More preferred. Within such a range, the pressure-sensitive adhesive composition for optical members has a long pot life and excellent workability. Is greatly improved.

  Moreover, it is preferable that it is 0.08-4 mass parts with respect to 100 mass parts of components (A), and, when using component (D), it is 0.1-1 mass parts. More preferred. Moreover, since the preferable specific example, the preferable range of usage-amount, etc. when using an imidazole compound are the same as the above, description is abbreviate | omitted here.

  Furthermore, in this use, it is preferable that a silane coupling agent (E) is included in the composition. Since the preferable specific example of the silane coupling agent (E), the preferable range of the amount used, and the like are the same as described above, the description thereof is omitted here.

  The application of the pressure-sensitive adhesive composition for optical members is not particularly limited, and examples thereof include a natural coater, a knife belt coater, a floating knife, a knife over roll, a knife on blanket, a spray, a dip, a kiss roll, a squeeze roll, a reverse roll, Various coating methods using apparatuses such as an air blade, a curtain flow coater, a doctor blade, a wire bar, a die coater, a comma coater, a baker applicator, and a gravure coater may be mentioned. Moreover, although the application thickness (thickness after drying) of the pressure-sensitive adhesive composition when used for an optical member may be selected according to the substrate used and the application, it is preferably 5 to 35 μm, more Preferably it is 15-30 micrometers.

  When the pressure-sensitive adhesive composition of the present invention is used for an optical member, the gel fraction of the pressure-sensitive adhesive layer after standing for 0.5 days in an atmosphere of 23 ° C. and 50% RH after pressure-sensitive processing is 50 to 95%. Preferably, it is 60 to 92%, more preferably 70 to 90%. If it is such a range, a punching process and a slit process can be rapidly performed as an optical member provided with the adhesive layer. In order to set the gel fraction as described above, the conditions may be appropriately selected, for example, by adjusting the amount of each component added to the above range.

  In the optical member of the present invention, the adhesive strength of the pressure-sensitive adhesive layer formed on the optical member is preferably about 0.5 to 9 (N / 25 mm), more preferably about 1 to 6 (N / 25 mm). An adhesive strength in such a range can be advantageous for reworkability. In the present specification, the “adhesive strength” is determined by measuring according to the adhesive tape / adhesive sheet test method of JIS Z0237 (2000), and more specifically described in the following examples. Measured according to method.

  The pressure-sensitive adhesive composition of the present invention used for optical members has a long pot life, excellent workability, a practical maturation time of 0.5 days after adhesive processing, and a substantial improvement in productivity. To do. Furthermore, the pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition of the present invention used for an optical member has an appropriate adhesive strength and adhesion to a substrate for an optical member, and further, metal corrosion inhibition / prevention Excellent light leakage resistance, durability, adherend contamination resistance, low temperature stability, and reworkability.

<Adhesive sheet>
The pressure-sensitive adhesive composition of the present invention can be formed into a pressure-sensitive adhesive sheet such as a sheet or a tape by coating on a base material or a separator and applying a drying (crosslinking) treatment to form a pressure-sensitive adhesive layer. it can. That is, this invention provides an adhesive sheet provided with the adhesive layer formed from the adhesive composition of this invention.

  As the base material of the adhesive sheet, polyester films such as polyethylene terephthalate film (PET film), plastic films such as polypropylene film and cellophane film, plastics such as polyurethane and ethylene-propylene terpolymer (EPT), foams of rubber, Various known thin leaf members such as paper and aluminum foil are used. Depending on the material, the surface of these base materials may be subjected to a ground treatment such as corona treatment, plasma treatment, or easy adhesion layer formation, or formation of an antistatic layer. For the separator, the surface of the same plastic film as the above-mentioned base material is subjected to a release treatment such as a silicone-based, fluorine-based, or long-chain alkyl-based release treatment agent, or a polypropylene film not subjected to such a release treatment. Various types can be used.

  When the pressure-sensitive adhesive layer is formed on the substrate, it may be provided on one side to be a single-sided pressure-sensitive adhesive sheet, or may be provided on both sides to be a double-sided pressure-sensitive adhesive sheet. When providing on both surfaces, it can also be set as the tape from which an adhesive kind differs on both surfaces using the adhesive composition of this invention only on one surface. When forming an adhesive layer on a separator, it can be used as a double-sided adhesive sheet.

  When using the adhesive composition of this invention for the adhesive layer of an adhesive sheet, the component (A) contained in a composition is 0.1-9 mass parts carboxyl group containing monomer (a-1), 0-1 It preferably contains a monomer component composed of a hydroxy group-containing (meth) acrylic monomer (a-2) by mass part and 99.9 to 90 parts by mass of a (meth) acrylic acid ester monomer (a-3), The weight average molecular weight is preferably 100,000 to less than 1,000,000. The total amount of component (a-1), component (a-2) and component (a-3) is 100 parts by mass.

  As for the usage-amount of the component (a-1) in the component (A) in an adhesive sheet use, it is more preferable that it is 0.1-9 mass parts, It is further more preferable that it is 0.3-9 mass parts, 0 It is especially preferable that it is 0.5-8.5 mass parts.

  The amount of the component (a-2) in the component (A) used for the pressure-sensitive adhesive sheet is more preferably 0 to 1 part by mass, further preferably 0 to 0.8 part by mass. It is especially preferable that it is -0.7 mass part.

  Furthermore, it is more preferable that the usage-amount of the component (a-3) in the component (A) in an adhesive sheet use is 99.9-90 mass parts, and it is 99.7-90.2 mass parts. More preferably, it is 99.5-90.5 mass parts.

  The total amount of the component (a-1) used in the component (A) and the component (a-2) used in the pressure-sensitive adhesive sheet is preferably 0.1 to 10 parts by mass, 0.3 It is more preferable that it is -9.8 mass parts, and it is still more preferable that it is 0.5-9.2 mass parts.

  As for the weight average molecular weight of the component (A) in an adhesive sheet use, it is more preferable that it is 100,000-1 million, and it is further more preferable that it is 200,000-900,000.

  Moreover, it is preferable that content of the component (B) in the adhesive composition for adhesive sheets is 0.05-5 mass parts with respect to 100 mass parts of components (A), 0.1-4 More preferably, it is part by mass.

  Moreover, it is preferable that content of a component (C) is 0.01-0.3 mass part with respect to 100 mass parts of components (A), and it is 0.02-0.3 mass part. More preferred. Within such a range, the pressure-sensitive adhesive composition for the pressure-sensitive adhesive sheet has a long pot life, excellent workability, and a practical adhesive performance can be achieved in a short time of 0.5 days after pressure-sensitive adhesive processing. Is greatly improved.

  Moreover, it is preferable that the usage-amount in the case of using a component (D) is 0.05-5 mass parts with respect to 100 mass parts of components (A), and it is 0.1-3 mass parts. More preferred. Moreover, since the preferable specific example, the preferable range of usage-amount, etc. when using an imidazole compound are the same as the above, description is abbreviate | omitted here.

  In this application, it is preferable that the silane coupling agent (E) is not contained in the composition.

  The application method of the pressure-sensitive adhesive composition for pressure-sensitive adhesive sheets is not particularly limited, and a conventionally known method is used. Specifically, natural coater, knife belt coater, floating knife, roll coat, air knife coat, knife over roll, knife on blanket, spray, dip, kiss roll, squeeze roll, reverse roll, air blade, curtain flow coater, doctor Various coating methods using apparatuses such as a blade, a wire bar, a die coater, a comma coater, a baker applicator, and a gravure coater may be mentioned. Of these, roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, and die coating are preferably used. Moreover, the application thickness (thickness after drying) of the composition formed on the pressure-sensitive adhesive sheet is not particularly limited, and can be appropriately selected depending on a desired application. Preferably, the coating thickness of the composition formed on the pressure-sensitive adhesive sheet (thickness of the pressure-sensitive adhesive layer; thickness after drying) is about 3 to 200 μm, more preferably about 5 to 100 μm.

  When the pressure-sensitive adhesive composition of the present invention is used for a pressure-sensitive adhesive sheet, the gel fraction of the pressure-sensitive adhesive layer after standing for 0.5 days in an atmosphere of 23 ° C. and 50% RH after the pressure-sensitive adhesive processing is 70 to 100%. Preferably, it is 80 to 99%, more preferably 83 to 98%. If it is such a range, a punching process and a slit process can be rapidly performed as an adhesive sheet provided with the adhesive layer. In order to set the gel fraction as described above, the conditions may be appropriately selected, for example, by adjusting the amount of each component added to the above range.

  In the pressure-sensitive adhesive sheet of the present invention, the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer formed on the pressure-sensitive adhesive sheet is preferably about 0.05 to 20 (N / 25 mm), more preferably about 0.1 to 20 (N / 25 mm). If it is the adhesive force of such a range, it can respond to adhesive sheets, such as a sheet form and a tape form which require various adhesive forces.

  The pressure-sensitive adhesive composition of the present invention used for the pressure-sensitive adhesive sheet has a long pot life and excellent workability, and has reached a practical pressure-sensitive adhesive performance within a short time of 0.5 days after pressure-sensitive adhesive processing, thus greatly improving productivity. To do. Furthermore, the pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition has an appropriate pressure-sensitive adhesive force and adhesion to a substrate, suppresses and prevents metal corrosion, adherend resistance, low temperature stability, and transparency. Excellent in heat resistance and moist heat resistance.

  The present invention will be described in further detail using the following examples and comparative examples. However, the technical scope of the present invention is not limited only to the following examples. The solid content and viscosity of the polymer solution obtained in the synthesis example, the viscosity of the pressure-sensitive adhesive composition, and the weight average molecular weight of the polymer (A) were measured by the following methods.

<Solid content>
About 1 g of the polymer solution is precisely weighed in a precisely weighed glass dish. After drying at 105 ° C. for 1 hour, the temperature is returned to room temperature, and the total mass of the glass dish and the remaining solid is precisely weighed. The solid content was calculated by the following formula 1, where X is the mass of the glass plate, Y is the total mass of the glass plate before drying and the polymer solution, and Z is the total mass Z of the glass plate and the remaining solid content.

<Viscosity>
The polymer solution in a glass bottle was temperature-controlled at 25 ° C. and measured with a B-type viscometer. The viscosity of the pressure-sensitive adhesive composition was measured twice immediately after the pressure-sensitive adhesive composition was prepared and 12 hours after the preparation.

<Weight average molecular weight>
The measurement was performed according to the measurement method and measurement conditions shown in Table 1 below.

(Synthesis Example 1)
In a flask equipped with a reflux condenser and a stirrer, 89.4 parts by mass of n-butyl acrylate (manufactured by Nippon Shokubai Co., Ltd.), 10 parts by weight of methyl acrylate (manufactured by Nippon Shokubai Co., Ltd.), 4-hydroxybutyl acrylate (Nippon Kasei Co., Ltd.) 0.1 parts by mass), 0.5 part by mass of acrylic acid (manufactured by Nippon Shokubai Co., Ltd.) and 120 parts by mass of ethyl acetate were added. Next, the mixture was heated to 65 ° C. while performing nitrogen substitution, 0.04 parts by mass of azobisisobutyronitrile (AIBN) was added, and polymerization was performed for 6 hours while maintaining 65 ° C. After the completion of the polymerization reaction, 280 parts by mass of ethyl acetate was added for dilution to obtain a polymer (sample name: A-1) solution. The obtained polymer solution had a solid content of 20% by mass and a viscosity of 5000 mPa · s. Moreover, the weight average molecular weight of the obtained polymer (A-1) was 1,600,000.

(Synthesis Examples 2 to 21)
In Synthesis Example 1, the same procedure as in Synthesis Example 1 was performed, except that the composition of the monomer component was changed to the composition shown in Table 1-1 and Table 1-2. A solution of combined (A-2) to (A-21) was obtained. Moreover, the solid content and viscosity of the obtained polymer (A-2)-(A-21) solution, and the weight average molecular weight of polymer (A-2)-(A-21) were measured. The results are shown in Table 1 below. In Table 1 below, “BA” is butyl acrylate; “MA” is methyl acrylate; “HEA” is 2-hydroxyethyl acrylate; “4HBA” is 4-hydroxybutyl acrylate. “HEAA” is N-2-hydroxyethylacrylamide; “AA” is acrylic acid.

Example 1
500 parts by mass of the polymer solution obtained in Synthesis Example 1 (100 parts by mass as the solid content of the polymer), Carbodilite (registered trademark) V-09 (Nisshinbo Chemical Co., Ltd.), which is a carbodiimide-based crosslinking agent (B) , Sample name B-2) 1 part by mass, Plenact KR 55 (Ajinomoto Fine Techno Co., Ltd., sample name C-2) which is a periodic table group 4 coupling agent (C) 0.02 part by mass, isocyanate-based crosslinking agent (D) Coronate (registered trademark) L (trimethylolpropane / tolylene diisocyanate trimer adduct, manufactured by Nippon Polyurethane Industry Co., Ltd., sample name D-1) 1 part by mass and silane coupling agent (E) A certain Shin-Etsu Silicone KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd., sample name E-2) 0.1 part by mass is mixed at room temperature (25 ° C.) for 10 minutes, and an adhesive group A solution in which the product was dissolved was obtained.

  This solution was applied on a peeled PET film (MRF38, thickness: 38 μm) by a baker applicator so that the thickness after drying was 25 μm, and dried at 90 ° C. for 3 minutes. After forming the pressure-sensitive adhesive layer, it was bonded to the polarizing plate to produce a polarizing plate with a pressure-sensitive adhesive layer.

(Examples 2-8, Comparative Examples 1-13)
Polymers synthesized in the above synthesis examples at the composition ratios shown in Tables 2 and 3 below, carbodiimide-based crosslinking agents, periodic table group 4 coupling agents, isocyanate-based crosslinking agents, silane coupling agents, and other additions Except having used the agent, it carried out similarly to Example 1, and prepared the solution in which the adhesive composition was melt | dissolving, and preparation of the polarizing plate with an adhesive layer. Carbodiimide-based crosslinking agents B-1, B-2 and B-3, and periodic table group 4 coupling agents C-1, C-2, C-3, C-4, C-5 and C-6, Isocyanate-based crosslinking agents D-1, D-2, D-3 and D-4, silane coupling agents E-1 and E-2, other additives F-1, F-2, F-3, F- Details of 4 and F-5 are as follows.

  About the polarizing plate with an adhesive layer of Examples 1-8 and Comparative Examples 1-13 obtained as mentioned above, each performance was evaluated according to the following method.

1. Gel fraction In place of the polarizing plate having the pressure-sensitive adhesive layer prepared in each example and comparative example, using a peel-treated polyester film, 0.5 days in an atmosphere of 23 ° C. and 50% RH after pressure-sensitive adhesive processing The gel fraction after standing and after 7 days was measured. As for the gel fraction, about 0.1 g of the pressure-sensitive adhesive composition left in an atmosphere of 23 ° C. and 50% RH was weighed, and the weight W1 (g) was measured. This was collected in a sample bottle, and about 30 g of ethyl acetate was added and left for 24 hours. The contents of the sample bottle after a lapse of a predetermined time are filtered off with a 200 mesh stainless steel wire mesh (the weight of the membrane is W2 (g)), and the wire mesh and the residue are dried at 90 ° C. for 1 hour. (G) was measured. The gel fraction was calculated from these measured values according to the following formula.

2. Metal corrosion inhibition / prevention The pressure-sensitive adhesive layer surface of the polarizing plate having the pressure-sensitive adhesive layer left for 0.5 days in an atmosphere of 23 ° C. and 50% RH is bonded to an aluminum foil, and in an atmosphere of 60 ° C. and 90% RH. It was left for 2 days and the corrosivity at that time was observed. In Tables 2 and 3 below, “◯” represents no change, and “x” represents whitening.

3. Light leakage resistance A polarizing plate having an adhesive layer left at 23 ° C. and 50% RH for 0.5 days is cut into 120 mm (polarizing plate MD direction) × 60 mm and 120 mm (polarizing plate TD direction) × 60 mm. Then, they were laminated so as to overlap each surface of the glass plate, and autoclaved for 20 minutes under the conditions of 50 ° C. and 0.49 MPa (5 kg / cm ² ). Thereafter, the appearance after being allowed to stand for 120 hours and 500 hours in an 80 ° C. atmosphere was observed. In Table 2 and Table 3 below, “◎” indicates that no light leakage was observed after 120 hours and 500 hours, “◯” indicates that no light leakage was observed after 120 hours, and “×” indicates that It represents that light leakage was observed, respectively.

4). Durability A polarizing plate having an adhesive layer that was allowed to stand for 0.5 days in an atmosphere of 23 ° C. and 50% RH was cut into 120 mm (polarizing plate MD direction) × 60 mm, bonded to a glass plate, 50 ° C., Autoclaving was performed for 20 minutes under the condition of 0.49 MPa (5 kg / cm ² ). Thereafter, the appearance after being allowed to stand for 120 hours in an atmosphere of 100 ° C. and in an atmosphere of 80 ° C. and 90% RH was observed. In Table 2 and Table 3 below, “◯” represents that foaming, floating, and peeling were not observed, and “X” represents that foaming, floating, and peeling were observed.

5. Adhesive strength A polarizing plate having an adhesive layer left for 0.5 days in an atmosphere of 23 ° C. and 50% RH is cut to a width of 25 mm and bonded to a glass plate at 50 ° C. and 0.49 MPa (5 kg / cm ² ). The autoclave process was performed for 20 minutes under these conditions. Using a tensile tester in an atmosphere of 23 ° C. and 50% RH at a peeling angle of 90 degrees and a peeling speed of 0.3 m / min, according to the adhesive tape / adhesive sheet test method described in JIS Z0237 (2000). The adhesive strength was measured.

6). 4. Adhesion to substrate The adhesion was observed when measuring the adhesive strength. In Table 2 and Table 3 below, “◯” represents that the pressure-sensitive adhesive was not peeled off from the base material, and “X” represents that the pressure-sensitive adhesive was peeled off from the base material.

7). Substrate contamination property 5. The contact angle of the glass plate surface before and after measuring the adhesive strength was measured. The contact angle was measured according to the wettability test method for the substrate glass surface described in JIS R3257 (1999). In Table 2 and Table 3 below, “◯” indicates that the contact angle change on the glass plate surface before and after the adhesion measurement is 3 ° or less, and “×” indicates the contact angle change on the glass plate surface before and after the adhesion measurement. Each case exceeds 3 °.

8). Low temperature stability A polarizing plate having an adhesive layer left for 0.5 days in an atmosphere of 23 ° C. and 50% RH was cut into 120 mm (polarizing plate MD direction) × 60 mm, and bonded to a glass plate at 50 ° C. Autoclaving was performed for 20 minutes under the condition of 0.49 MPa (5 kg / cm ² ). Then, the external appearance after leaving for 120 hours in -40 degreeC atmosphere was observed. In Table 2 and Table 3 below, “◯” indicates that foaming, floating, peeling, and recrystallized materials were not observed, and “×” indicates that foaming, floating, peeling, and recrystallized materials were observed, respectively. Represent.

9. Reworkability 5. The peeled state was observed when measuring the adhesive strength. In Table 2 and Table 3 below, “◯” indicates that interfacial fracture was observed, and “×” indicates that the adhesive was transferred and / or cohesive fracture was observed on the glass plate (adhered body). Represent each.

  Each evaluation result is summarized and shown in Table 2 and Table 3 below.

  As apparent from Table 2 and Table 3 above, the pressure-sensitive adhesive compositions (Examples 1 to 8) of the present invention are compared with the pressure-sensitive adhesive compositions (Comparative Examples 1 to 13) that are outside the scope of the present invention. Excellent pot life and curing acceleration effect. From this, it is considered that the pressure-sensitive adhesive composition of the present invention can greatly improve workability and productivity. Moreover, as is clear from Table 2 and Table 3 above, the polarizing plates (Examples 1 to 8) using the pressure-sensitive adhesive composition of the present invention are pressure-sensitive adhesive compositions (Comparative Examples 1 to 1) that are outside the scope of the present invention. Compared with the polarizing plate using 13), it is excellent in light leakage resistance, durability, adhesion to the substrate, adherend contamination, low temperature stability and reworkability. In addition, "-" in the table means that gelation occurred within 10 minutes after blending, so that the viscosity measurement immediately after blending could not be performed and the performance test could not be performed.

(Synthesis Example 22)
In a flask equipped with a reflux condenser and a stirrer, 60 parts by mass of n-butyl acrylate (manufactured by Nippon Shokubai Co., Ltd.), 30.5 parts by weight of 2-ethylhexyl acrylate (manufactured by Nippon Shokubai Co., Ltd.) and vinyl acetate (Electrochemical Industry) Co., Ltd.) 2.5 parts by mass, acrylic acid (manufactured by Nippon Shokubai Co., Ltd.) 7 parts by mass, and ethyl acetate 150 parts by mass were added. Next, the temperature was raised to 65 ° C. while performing nitrogen substitution, 0.1 parts by mass of azobisisobutyronitrile (AIBN) was added, 0.05 parts by mass of AIBN was further added after 1 hour, and the temperature was maintained at 65 ° C. Polymerization was carried out for 6 hours. After completion of the polymerization reaction, 36 parts by mass of ethyl acetate was added for dilution, followed by cooling to room temperature to obtain a polymer (sample name: A-22) solution. The obtained polymer solution had a solid content of 35% and a viscosity of 4000 mPa · s. Moreover, the weight average molecular weight of the obtained polymer (A-22) was 750,000.

(Synthesis Examples 23 to 43)
In Synthesis Example 23, the same procedure as in Synthesis Example 22 was performed, except that the composition of the monomer component was changed to the composition shown in Tables 4-1 and 4-2. A solution of combined (A-23) to (A-43) was obtained. Moreover, the solid content and viscosity of the obtained polymer (A-23)-(A-43) solution, and the weight average molecular weight of polymer (A-23)-(A-43) were measured. The results are shown in Table 4 below. In Table 4 below, “BA” is butyl acrylate; “2EHA” is 2-ethylhexyl acrylate; “MA” is methyl acrylate; “VAc” is vinyl acetate; “HEA” is 2-hydroxyethyl acrylate; “4HBA” is 4-hydroxybutyl acrylate; “HEAA” is N-2-hydroxyethyl acrylamide; “AA” is acrylic acid; “AM” is acrylamide.

Example 9
286 parts by mass of the polymer solution obtained in Synthesis Example 22 (100 parts by mass as the solid content of the polymer), Carbodilite (registered trademark) V-05 (made by Nisshinbo Chemical Co., Ltd.), which is a carbodiimide crosslinking agent (B), Sample name B-1) 0.4 part by mass, Preneact (registered trademark) KR TTS (sample name C-1 manufactured by Ajinomoto Fine-Techno Co., Ltd.) which is a periodic table group 4 coupling agent (C) 0.05 part by mass , And Duranate (registered trademark) 24A-100 (hexamethylene diisocyanate bullet type, manufactured by Asahi Kasei Chemicals Corporation, sample name D-5) which is an isocyanate crosslinking agent (D) at room temperature (25 ° C.) The mixture was mixed for 10 minutes to obtain a solution in which the pressure-sensitive adhesive composition was dissolved.

  This solution was applied onto a peeled PET film (Mitsubishi Resin, MRF38, thickness: 38 μm) with a baker applicator so that the thickness after drying was 25 μm, and dried at 90 ° C. for 3 minutes to adhere. After forming the adhesive layer, the adhesive sheet (1) is produced by further bonding the adhesive layer side to a PET film (trade name Lumirror (registered trademark) S10 # 25, thickness: 23 μm, manufactured by Toray Industries, Inc.). did.

(Examples 10-16, Comparative Examples 14-27)
Polymers synthesized in the above Synthesis Examples 23 to 43, carbodiimide crosslinking agents, periodic table group 4 coupling agents, isocyanate crosslinking agents, and other additives were used at the composition ratios shown in Table 5 and Table 6 below. Except for the above, preparation of a solution in which the pressure-sensitive adhesive composition was dissolved and production of a pressure-sensitive adhesive sheet were carried out in the same manner as in Example 9, and pressure-sensitive adhesive sheets (2) to (8) and comparative pressure-sensitive adhesive sheet (1). To (14). Carbodiimide crosslinking agents B-1, B-2 and B-3, and periodic table group 4 coupling agents C-1, C-2, C-3, C-4, C-5 and C-6, isocyanate The details of the crosslinking agents D-1, D-2, D-3, D-4 and D-5, and other additives F-1, F-2, F-3, F-4 and F-5 are as follows. It is as follows.

  Each performance was evaluated according to the following method about the adhesive sheet of Examples 9-16 and Comparative Examples 14-27 obtained as mentioned above.

1. Gel fraction In place of the PET film having the pressure-sensitive adhesive layer produced in Examples 9 to 16 and Comparative Examples 14 to 27, the polyester film subjected to the release treatment was used, and the pressure-sensitive adhesive layer was peeled on the polyester film. After applying the coating to a thickness of 25 μm after drying, measure the gel fraction after standing for 0.5 days and after standing for 7 days in an atmosphere of 23 ° C. and 50% RH after adhesive processing. did. As for the gel fraction, about 0.1 g of the pressure-sensitive adhesive composition left in an atmosphere of 23 ° C. and 50% RH was weighed, and the weight W1 (g) was measured. This was collected in a sample bottle, and about 30 g of ethyl acetate was added and left for 24 hours. The contents of the sample bottle after a lapse of a predetermined time are filtered off with a 200 mesh stainless steel wire mesh (the weight of the membrane is W2 (g)), and the wire mesh and the residue are dried at 90 ° C. for 1 hour. (G) was measured. The gel fraction was calculated from these measured values according to the following mathematical formula 2.

2. Metal corrosion inhibition / prevention property The pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive sheet that was allowed to stand for 0.5 days in an atmosphere of 23 ° C. and 50% RH is bonded to an aluminum foil, and then left for 2 days in an atmosphere of 60 ° C. and 90% RH. The corrosivity at that time was observed. In Tables 5 and 6 below, “◯” represents no change, and “x” represents whitening.

3. Adhesive strength Adhesive sheet left for 0.5 days in an atmosphere of 23 ° C and 50% RH is cut into a width of 25 mm, and this is pressure-bonded by a method of reciprocating once with a 2 kg roller onto a stainless steel plate, and at 23 ° C and 50% RH. For 20 minutes. Then, using a tensile tester, the adhesive tape / adhesive sheet test method described in JIS Z0237 (2000) at an exfoliation angle of 180 degrees and an exfoliation speed of 0.3 m / min in an atmosphere of 23 ° C. and 50% RH. The adhesive strength was measured accordingly.

4). 2. Adhesiveness to substrate At the time of measuring the adhesive strength, the adhesion to the adhesive sheet (base material) was evaluated. In Table 5 and Table 6 below, “◯” represents that the pressure-sensitive adhesive was not peeled off from the substrate, and “x” represents that the pressure-sensitive adhesive was peeled off from the substrate.

5. Adherent contamination property 3. The contact angle of the stainless steel plate before and after measuring the adhesive force was measured. The contact angle was measured according to the wettability test method for the substrate glass surface described in JIS R3257 (1999). In Tables 5 and 6 below, “◯” indicates that the contact angle change of the stainless steel plate surface before and after the adhesion measurement is 3 ° or less, and “×” indicates that the contact angle change of the stainless steel plate surface before and after the adhesion measurement. Each case exceeds 3 °.

6). Low temperature stability The pressure-sensitive adhesive sheet left for 0.5 days in an atmosphere of 23 ° C. and 50% RH is pressure-bonded to the stainless steel plate by a single reciprocation with a 2 kg roller, and left in an atmosphere of 23 ° C. and 50% RH for 1 hour. did. Then, the external appearance after leaving for 120 hours in -40 degreeC atmosphere was observed. In Table 5 and Table 6 below, “◯” indicates that foaming, floating, peeling, and recrystallized material were not observed, and “×” indicates that foaming, floating, peeling, and recrystallized material were observed, respectively. Represent.

7). Transparency of the pressure-sensitive adhesive layer The transparency of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet left for 0.5 days in an atmosphere of 23 ° C. and 50% RH was visually confirmed. In Table 5 and Table 6 below, “◯” represents the case where transparency was good, and “x” represents the case where white turbidity was observed in the pressure-sensitive adhesive layer.

8). Heat resistance The pressure-sensitive adhesive sheet left for 0.5 days in an atmosphere of 23 ° C. and 50% RH was pressure-bonded to the stainless steel plate by a single reciprocation with a 2 kg roller, and left for 1 hour in an atmosphere of 23 ° C. and 50% RH. . Thereafter, the appearance after leaving for 500 hours in an 80 ° C. atmosphere was observed. In Tables 5 and 6 below, “◯” represents that foaming, floating, and peeling were not observed, and “X” represents that foaming, floating, and peeling were observed.

9. Moisture and heat resistance The pressure-sensitive adhesive sheet left for 0.5 days in an atmosphere of 23 ° C. and 50% RH was pressure-bonded to the stainless steel plate by a single reciprocation with a 2 kg roller, and left for 1 hour in an atmosphere of 23 ° C. and 50% RH. . Thereafter, the appearance after being allowed to stand in an atmosphere of 60 ° C. and 90% RH for 500 hours was observed. In Tables 5 and 6 below, “◯” represents that foaming, floating, and peeling were not observed, and “X” represents that foaming, floating, and peeling were observed.

  Each evaluation result is summarized and shown in Table 5 and Table 6 below.

  As is clear from Table 5 and Table 6 above, the pressure-sensitive adhesive compositions (Examples 9 to 16) of the present invention are compared with the pressure-sensitive adhesive compositions (Comparative Examples 14 to 27) that are outside the scope of the present invention. Excellent pot life and curing acceleration effect. From this, it is considered that the pressure-sensitive adhesive composition of the present invention can greatly improve workability and productivity. Moreover, as is clear from Table 5 and Table 6 above, the adhesive sheets of Examples 9 to 16 of the present invention have better adhesion to the substrate and adherend contamination than the adhesive sheets of Comparative Examples 14 to 27. Properties, low temperature stability, transparency of the pressure-sensitive adhesive layer, heat resistance, and heat and humidity resistance.

Claims (4)

0.1 to 9 parts by mass of a carboxyl group-containing monomer (a-1), 0 to 1 part by mass of a hydroxy group-containing (meth) acrylic monomer (a-2), and 99.9 to 90 parts by mass of (meth). Monomer component comprising the acrylic ester monomer (a-3) (however, the total amount of the carboxyl group-containing monomer, hydroxy group-containing (meth) acrylic monomer, and (meth) acrylic ester monomer is 100 parts by mass) 100 parts by weight of (meth) acrylic copolymer (A) having a weight average molecular weight of 100,000 to 2,000,000,
0.05 to 5 parts by mass of a carbodiimide crosslinking agent (B) with respect to 100 parts by mass of the (meth) acrylic copolymer (A),
0.01-0.3 parts by mass of a titanium coupling agent, a zirconium coupling agent or a hafnium coupling agent (C),
A pressure-sensitive adhesive composition comprising:   The pressure-sensitive adhesive composition according to claim 1, further comprising 0.05 to 5 parts by mass of an isocyanate crosslinking agent (D) with respect to 100 parts by mass of the (meth) acrylic copolymer (A).   An optical member provided with the adhesive layer formed from the adhesive composition of Claim 1 or 2.   A pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition according to claim 1.