KR20080097948A - Aqueous dispersion type pressure-sensitive adhesive composition and pressure-sensitive adhesive film - Google Patents

Abstract

An aqueous dispersion type pressure-sensitive adhesive composition and an adhesive film are provided to ensure firm adhesion due to high adhesive force with a substrate and to obtain excellent durability under a high temperature and high humidity circumstances due to high heat resistance and waterproof property. An aqueous dispersion type pressure-sensitive adhesive composition comprises an aqueous dispersion type copolymer obtained by reacting a reaction component consisting of (meth)alkyl ester acrylate, (meth)acrylic acid, phosphate group-containing vinyl monomer and alkoxysilyl group-containing vinyl monomer, having C4-C18 linear or branched alkyl group; and a cross-linking agent having the reactivity with a carboxylic group. The mixing ratio of the cross-linking agent is 0.07-4 parts by weight based on the aqueous dispersion type copolymer. The aqueous dispersion type adhesive layer consisting of the aqueous dispersion type copolymer has an elongation degree of 200% or less at 90 deg.C.

Description

Aqueous dispersion type adhesive composition and adhesive film {AQUEOUS DISPERSION TYPE PRESSURE-SENSITIVE ADHESIVE COMPOSITION AND PRESSURE-SENSITIVE ADHESIVE FILM}

The present invention relates to a water-dispersible pressure-sensitive adhesive composition and an adhesive film.

Background Art Conventionally, optical films such as polarizing films, retardation films, brightness enhancement films, and viewing angle expansion films have been used for various industrial purposes, and for example, liquid crystal displays, organic electroluminescent devices (organic EL display devices), plasma display panels (PDP), and the like. It is adhere | attached to the image display apparatus of and used.

As such an optical film, the adhesive optical film which laminated | stacked the adhesive on the optical film is known.

In recent years, the use of organic solvents has been reduced in view of environmental loads, and there has been a demand for a switch from a solvent type adhesive using an organic solvent as a solvent to a water dispersion type adhesive using water as a dispersion medium.

As such a water-dispersible pressure-sensitive adhesive, for example, a pressure-sensitive adhesive composition comprising a copolymer emulsion, in which the copolymer is copolymerized with 10 to 50% by weight of 2-ethylhexyl methacrylate based on the entire copolymer, and further, a glass of copolymer A pressure-sensitive adhesive composition having a transition temperature of -25 ° C or lower has been proposed (see, for example, Japanese Unexamined Patent Application Publication No. 2001-254063).

However, although the conventional water-dispersible pressure-sensitive adhesive including the Japanese Patent Laid-Open No. 2001-254063 described above has improved adhesion to hydrophobic adherends such as polyolefins, adhesion to hydrophilic adherends such as glass is particularly low. It is difficult to adhere | attach firmly to the glass substrate used for an image display apparatus.

In addition, the water-dispersible pressure-sensitive adhesive laminated on the optical film is required to have high heat resistance and moisture resistance, in which adhesion and the like are not lowered even by severe heating or humidification.

However, in the water-dispersible pressure-sensitive adhesive described above, there is a defect that bubbles or deformation occur due to severe heating, humidification, or the like, and the optical properties are lowered.

An object of the present invention is to provide a pressure-sensitive adhesive film having a pressure-sensitive adhesive layer composed of a water-dispersible pressure-sensitive adhesive composition having high adhesion to a substrate and having high heat resistance and moisture resistance and the water-dispersible pressure-sensitive adhesive composition.

The water-dispersible pressure-sensitive adhesive composition of the present invention is a reaction containing a (meth) acrylic acid alkyl ester, a (meth) acrylic acid, a phosphoric acid group-containing vinyl monomer, and an alkoxysilyl group-containing vinyl monomer having 4 to 18 carbon atoms and having a linear or branched alkyl group. A water-dispersible pressure-sensitive adhesive composition comprising a water-dispersible copolymer obtained by reacting a component and a crosslinking agent having reactivity with a carboxyl group, wherein the blending ratio of the crosslinking agent is 0.07 to 4 parts by weight based on 100 parts by weight of the water-dispersion copolymer, The pressure-sensitive adhesive layer made of the water-dispersible pressure-sensitive adhesive composition is characterized in that the elongation at 90 ° C. is 200% or less by the following test.

Test: The water-dispersible pressure-sensitive adhesive composition is heated to prepare a pressure-sensitive adhesive layer, which is molded into a cylindrical shape having a cross-sectional area of 4.6 mm ² and a length of 30 mm to prepare a test piece. Then, the specimen is measured after left for one hour at 90 ℃, the length L ₀ of the initial test pieces. Thereafter, one end of the test piece was fixed, a 12 g weight was attached to the other end of the test piece, the test piece was hanged at 90 ° C. for 2 hours, and the length L ₁ (mm) of the test piece after the test piece was dropped for 2 hours was measured. The elongation is calculated by one.

[Equation 1]

Elongation (%) = (L ₁ -L ₀ ) / L ₀ × 100

Moreover, in the water dispersion type adhesive composition of this invention, it is suitable that the said crosslinking agent is a compound which has a carbodiimide group.

Moreover, in the water dispersion type adhesive composition of this invention, it is suitable that the said crosslinking agent is a crosslinking agent which has an oxazoline group, and the compounding ratio of the said crosslinking agent is 0.07-1.5 weight part with respect to 100 weight part of said water dispersion type copolymers.

Moreover, in the water dispersion type adhesive composition of this invention, it is suitable that the said water dispersion type pressure-sensitive adhesive composition has a gel fraction of 80 to 95% by weight when immersed in ethyl acetate.

In addition, the pressure-sensitive adhesive film of the present invention is provided with a pressure-sensitive adhesive layer made of a water-dispersible pressure-sensitive adhesive composition, wherein the water-dispersible pressure-sensitive adhesive composition has an alkyl group having 4 to 18 carbon atoms and a linear or branched alkyl group, (meth) ) A water-dispersion copolymer obtained by reacting a reaction component containing an acrylic acid, a phosphoric acid group-containing vinyl monomer and an alkoxysilyl group-containing vinyl monomer, and a crosslinking agent having reactivity with a carboxyl group, wherein the blending ratio of the crosslinking agent is the water dispersion type copolymer. It is 007-4 weight part with respect to 100 weight part, The said adhesive layer is characterized by the elongation at 90 degreeC by the following test being 200% or less.

Test: The water-dispersible pressure-sensitive adhesive composition is heated to prepare a pressure-sensitive adhesive layer, which is molded into a cylindrical shape having a cross-sectional area of 4.6 mm ² and a length of 30 mm to prepare a test piece. Then, a test piece to measure the length L ₀ of the was allowed to stand for 1 hour at 90 ℃ initial specimen. Thereafter, one end of the test piece was fixed, and a 12 g weight was attached to the other end of the test piece, the test piece was hanged at 90 ° C. for 2 hours, and the length of the test piece L ₁ (mm) after the test was dropped for 2 hours was measured. Elongation is calculated by Equation 1.

[Equation 1]

Elongation (%) = (L ₁ -L ₀ ) / L ₀ × 100

Moreover, in the adhesive film of this invention, it is suitable that the said crosslinking agent is a compound which has a carbodiimide group.

Moreover, in the adhesive film of this invention, it is suitable that the said crosslinking agent is a crosslinking agent which has an oxazoline group, and the compounding ratio of the said crosslinking agent is 0.07-1.5 weight part with respect to 100 weight part of said water dispersion type copolymers.

The adhesive film provided with the adhesive layer which consists of a water-dispersible adhesive composition of this invention and this water-dispersible adhesive composition has high adhesive force with a board | substrate, and can achieve strong adhesiveness. Moreover, since it has high heat resistance and moisture resistance, the outstanding durability can be obtained in high temperature, high humidity atmosphere.

In particular, the pressure-sensitive adhesive film having the pressure-sensitive adhesive layer composed of the water-dispersible pressure-sensitive adhesive composition and the water-dispersible pressure-sensitive adhesive composition of the present invention can effectively prevent the occurrence of bubbles and deformation at high temperature and high humidity. For this reason, the fall of an optical characteristic can be prevented effectively.

The water dispersion type adhesive composition of this invention contains a water dispersion type copolymer and a crosslinking agent.

The said water dispersion type copolymer is obtained by making the reaction component containing a (meth) acrylic-acid ester, (meth) acrylic acid, a phosphoric acid group containing vinyl monomer, and an alkoxysilyl group containing vinyl monomer react.

Alkyl (meth) acrylates are alkyl (meth) acrylates (alkyl methacrylates and / or alkyl acrylates) having an alkyl group having 4 to 18 carbon atoms and a linear or branched alkyl group, for example, (meth) butyl acrylate, Isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, neopentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, ( Heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isocyl (meth) acrylate, nonyl (meth) nonyl acrylate, isononyl (meth) acrylate, (meth) decyl acrylate, (meth Isodecyl acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, (meth) Heptadecyl acrylate, (meth Octadecyl acrylate etc. are mentioned. Among these alkyl (meth) acrylates, butyl acrylate is preferable. These alkyl (meth) acrylates can be used alone or in combination.

The blending ratio of the alkyl (meth) acrylate ester is, for example, 60 to 99 parts by weight, preferably 80 to 99 parts by weight, more preferably 80 to 98 parts by weight based on 100 parts by weight of the reaction component.

As (meth) acrylic acid, methacrylic acid and acrylic acid are mentioned, for example.

(Meth) acrylic acid can be used individually or in combination. The blending ratio of (meth) acrylic acid is, for example, 0.5 to 15 parts by weight, preferably 0.5 to 10 parts by weight, more preferably 1 to 10 parts by weight based on 100 parts by weight of the reaction component. When less than the said range, the cohesion force of a water dispersion type adhesive composition may fall, and when more than the said range, the stability at the time of emulsion polymerization and the water resistance of a water dispersion type adhesive composition may fall.

The phosphoric acid group-containing vinyl monomer is, for example, a polyalkylene oxide (meth) acrylate phosphate ester represented by the following formula (1),

(In formula 1, R <^1> is a hydrogen atom or a methyl group, R <^2> is a polyoxyalkylene group, X represents a phosphoric acid group or its salt.)

As a polyoxyalkylene group represented by R <^{2>, it} is represented by following General formula (2),

(In Formula 2, n represents an integer of 1-4, m represents an integer of 2 or more.)

Examples include polyoxyethylene groups (corresponding to n = 2 in Formula 2), polyoxypropylene groups (corresponding to n = 3 in Formula 2), and random, block or graft units thereof, and the like. The degree of polymerization of these oxyalkylene groups, i.e., m in the formula (2), is preferably 4 or more and usually 40 or less.

The higher the degree of polymerization of the oxyalkylene group, the higher the mobility of the side chains having the phosphoric acid group, and the faster the interaction with glass, thereby improving the adhesion of the water-dispersible pressure-sensitive adhesive composition to the glass substrate.

In addition, the phosphoric acid group represented by X or a salt thereof is represented by the following formula (3),

(In formula (3), M ¹ and M ² each independently represent a hydrogen atom or a cation.)

The cation is not particularly limited, and examples thereof include inorganic cations such as alkali metals such as sodium and potassium, alkali earth metals such as calcium and magnesium, and organic cations such as quaternary amines.

Moreover, what is marketed generally can use the phosphoric acid group containing vinyl monomer, For example, Sipomer PAM-100 (made by Rodier Nikka Co., Ltd.), Phosmer PE (made by Universal Chemical Co., Ltd.), Phosmer PEH (Universal Chemical ( Mono) [poly (ethylene oxide) methacrylate] phosphate esters such as)), Phosmer PEDM (manufactured by Universal Chemical Co., Ltd.), such as Sipomer PAM-200 (manufactured by Rodier Nikka Corporation), Phosmer PP Mono [poly (propylene oxide) methacrylate] phosphate ester, such as Chemical Co., Ltd. product, Phosmer PPH (Universal Chemical Co., Ltd. product), Phosmer PPDM (Universal Chemical Co., Ltd. product), etc. are mentioned.

These phosphoric acid group containing vinyl monomers can be used individually or in combination.

The phosphoric acid group concentration in the phosphoric acid group-containing vinyl monomer is, for example, 0.01 to 0.45 mmol / g, preferably 0.02 to 0.20 mmol / g in the reaction component. In order to make the concentration of the phosphate group in the phosphate group-containing vinyl monomer within the above range, it is also dependent on the molecular weight of the phosphate group-containing vinyl monomer, but the mixing ratio of the phosphate group-containing vinyl monomer is, for example, 0.5 to 20 parts by weight, preferably 0.5 to 100 parts by weight of the reaction component. To 10 parts by weight, more preferably 1 to 5 parts by weight.

When the phosphate group concentration and compounding ratio of a phosphate group containing vinyl monomer are less than the said range, the effect of the adhesive force improvement to a glass substrate may not fully be acquired. When the phosphate group concentration and the compounding ratio of the phosphate group-containing vinyl monomer are more than the above ranges, the stability during emulsion polymerization and the water resistance of the water-dispersible pressure-sensitive adhesive composition may be lowered, and the elasticity of the water-dispersible pressure-sensitive adhesive composition is increased, thereby lowering the adhesiveness. There is a case.

As an alkoxy silyl group containing vinyl monomer, a silicone type (meth) acrylate monomer, a silicone type vinyl monomer, etc. are mentioned, for example.

Examples of the silicone-based (meth) acrylate monomers include (meth) acryloyloxymethyl-trimethoxysilane, (meth) acryloyloxymethyl-triethoxysilane and 2- (meth) acryloyloxyethyl-tri Methoxysilane, 2- (meth) acryloyloxyethyl-triethoxysilane, 3- (meth) acryloyloxypropyl-trimethoxysilane, 3- (meth) acryloyloxypropyl-triethoxy Silane, 3- (meth) acryloyloxypropyl-tripropoxysilane, 3- (meth) acryloyloxypropyl-triisopropoxysilane, 3- (meth) acryloyloxypropyl-tributoxysilane (Meth) acryloyloxyalkyl-trialkoxysilanes such as, for example, (meth) acryloyloxymethyl-methyldimethoxysilane, (meth) acryloyloxymethyl-methyldiethoxysilane, 2- ( (Meth) acryloyloxyethyl-methyldimethoxysilane, 2- (meth) acryloyloxy ethyl-methyldi Methoxysilane, 3- (meth) acryloyloxypropyl-methyldimethoxysilane, 3- (meth) acryloyloxypropyl-methyldiethoxysilane, 3- (meth) acryloyloxypropyl-methyldi Propoxysilane, 3- (meth) acryloyloxypropyl-methyldiisopropoxysilane, 3- (meth) acryloyloxypropyl-methyldibutoxysilane, 3- (meth) acryloyloxypropyl- Ethyldimethoxysilane, 3- (meth) acryloyloxypropyl-ethyldiethoxysilane, 3- (meth) acryloyloxypropyl-ethyldipropoxysilane, 3- (meth) acryloyloxypropyl -Ethyldiisopropoxysilane, 3- (meth) acryloyloxypropyl-ethyldibutoxysilane, 3- (meth) acryloyloxypropyl-propyldimethoxysilane, 3- (meth) acrylo (Meth) acryloyloxyalkyl-alkyl dialkoxysilanes, such as yloxypropyl propyl diethoxysilane, and (meth) corresponding to these One oxyalkylene a krill-and the like can be mentioned dialkyl (mono) alkoxysilanes.

Moreover, as a silicone type vinyl monomer, besides vinyltrialkoxysilane, such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltriisopropoxysilane, and vinyltributoxysilane, it respond | corresponds to these, for example. Vinylalkyl dialkoxysilane or vinyldialkylalkoxysilane, such as vinylmethyltrimethoxysilane, vinylmethyltriethoxysilane, β-vinylethyltrimethoxysilane, β-vinylethyltriethoxysilane, γ-vinylpropyl In addition to vinylalkyl trialkoxysilanes, such as a trimethoxysilane, (gamma) -vinylpropyl triethoxysilane, (gamma) -vinylpropyl tripropoxysilane, (gamma) -vinylpropyl triisopropoxysilane, (gamma) -vinylpropyl tributoxysilane, (Vinylalkyl) alkyl dialkoxysilanes or (vinylalkyl) dialkyl (mono) corresponding to these Alkoxysilane etc. are mentioned.

Among these alkoxysilyl group-containing vinyl monomers, Preferably silicone type (meth) acrylate monomer is mentioned, More preferably, 3-methacryloyl oxypropyl- trimethoxysilane is mentioned.

These alkoxysilyl group containing vinyl monomers can be used singly or in combination.

The compounding ratio of the alkoxysilyl group containing vinyl monomer is 0.001-1 weight part with respect to 100 weight part of reaction components, Preferably it is 0.01-0.1 weight part. When less than the said range, crosslinking by an alkoxysilyl group will be insufficient, and the cohesion force of a water-dispersible adhesive composition will fall, or the adhesiveness improvement of a water-dispersible adhesive composition and a glass substrate will not be obtained, and if it is more than the said range, when emulsion polymerization is carried out, May cause a decrease in stability or a decrease in adhesiveness.

In addition, the reaction component may further contain a copolymerizable vinyl monomer copolymerizable with an alkyl (meth) acrylate ester.

As such a copolymerizable vinyl monomer, the (meth) acrylic-acid alicyclic hydrocarbon ester which has a C6 or more alicyclic hydrocarbon group, such as cyclohexyl (meth) acrylic-acid, boryl (meth) acrylate, and isobornyl (meth) acrylate, for example. For example, aromatic vinyl monomers such as styrene, such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and linear or (Meth) acrylic acid alkyl ester which has a branched alkyl group, for example, (meth) acrylic acid aryl esters, such as phenyl (meth) acrylate, for example, alkoxy groups, such as methoxy ethyl (meth) acrylate and ethoxy ethyl (meth) acrylate Unsaturated monomers such as olefinic monomers such as ethylene, propylene, isoprene, butadiene and isobutylene, such as vinyl ether Inyl ether monomers such as halogen atom-containing unsaturated monomers such as vinyl chloride, and others such as N-vinylpyrrolidone, N- (1-methylvinyl) pyrrolidone, N-vinylpyridine, N-vinylpiperidone , N-vinylpyrimidine, N-vinyl piperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyl oxazole, N-vinyl morpholine, (meth) acrylic acid tetrahydrofurfuryl And vinyl group-containing heterocyclic compounds such as acrylate ester monomers containing halogen atoms such as fluorine atoms such as fluorine (meth) acrylate.

Moreover, as a copolymerizable vinyl monomer, the functional group containing vinyl monomer containing a functional group is mentioned.

Such functional group-containing vinyl monomers include, for example, unsaturated carboxylic acids such as fumaric acid, maleic acid, itaconic acid, crotonic acid and cinnamic acid, and carboxyl group-containing vinyls such as unsaturated dicarboxylic anhydrides such as itaconic anhydride, maleic anhydride and fumaric anhydride. Monomers (except (meth) acrylic acid), for example, carboxylic acid esters such as vinyl acetate and vinyl propionate, such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxybutyl acrylate Hydroxyl group-containing vinyl monomers such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N- Butyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methyl all propane (meth) acrylamide And amide group-containing unsaturated monomers such as N-vinyl carboxylic acid amide, for example, glycidyl group-containing unsaturated monomers such as glycidyl (meth) acrylate and methylglycidyl (meth) acrylate, such as acrylonitrile and meta. Cyano group-containing unsaturated monomers, such as chloronitryl, for example, isocyanate group-containing unsaturated monomers such as 2-methacryloyloxyethyl isocyanate, for example, styrenesulfonic acid, allylsulfonic acid, 2- Sulfonic acid group-containing unsaturated monomers such as (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxynaphthalene sulfonic acid, For example, maleimide monomers such as N-cyclohexyl maleimide, N-isopropyl maleimide, N-lauryl maleimide, N-phenyl maleimide, such as N-methyl Itaconimide, N-ethyl itaconimide, N-butyl itaconimide, N-octyl itaconimide, N-2-ethyl hexyl itaconimide, N-cyclohexyl itaconimide, N Itaconimide-based monomers such as lauryl itaciconimide, such as N- (meth) acryloyloxy methylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, Succinimide-based monomers such as N- (meth) acryloyl-8-oxyoctamethylene succinimide, such as (meth) acrylic acid polyethylene glycol, (meth) acrylic acid polypropylene glycol, (meth) acrylic acid Glycol type acrylic ester monomers, such as a methoxyethylene glycol and (meth) acrylic-acid methoxy polypropylene glycol, etc. are mentioned.

Moreover, a polyfunctional monomer is mentioned as said functional group containing vinyl monomer.

Examples of the multifunctional monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and trimethylol propane tri (meth). (Mono or poly) such as (mono or poly) ethylene glycol di (meth) acrylate such as acrylate and tetraethylene glycol di (meth) acrylate and propylene glycol di (meth) acrylate In addition to (mono or poly) alkylene glycol di (meth) acrylates such as propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol die (Meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipenta Erythritol hexa (meth) acrylate, divinylbenzene, etc. are mentioned. Moreover, epoxy acrylate, polyester acrylate, urethane acrylate, etc. are mentioned as a multifunctional monomer.

The copolymerizable vinyl monomers can be used alone or in combination.

Among these copolymerizable vinyl monomers, (meth) acrylic acid alicyclic hydrocarbon esters having an alicyclic hydrocarbon group having 6 or more carbon atoms are preferable, and methacrylic acid cyclohexyl is more preferable.

The copolymerizable vinyl monomer is optionally blended with the reaction component, and the blending ratio thereof is, for example, 39 parts by weight or less, preferably 19 parts by weight or less, and more preferably 18 parts by weight or less based on 100 parts by weight of the reaction component.

By mix | blending these copolymerizable vinyl monomers with a reaction component, the adhesiveness of a water dispersion type adhesive composition can be improved.

In order to obtain a water dispersion type copolymer, the said reaction component is copolymerized by polymerization methods, such as emulsion polymerization, for example.

As emulsion polymerization, a polymerization initiator, an emulsifier, a chain transfer agent, etc. are mixed suitably in water and copolymerized with the said reaction component as needed, for example. More specifically, well-known emulsion polymerization methods, such as a batch injection method (batch polymerization method), a monomer dropping method, and a monomer emulsion dropping method, can be employ | adopted. On the other hand, as the monomer dropping method, continuous dropping or divided dropping is appropriately selected. Although reaction conditions etc. are suitably selected, polymerization temperature is 20-100 degreeC, for example.

There is no restriction | limiting in particular as a polymerization initiator, The polymerization initiator normally used for emulsion polymerization is used. For example, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylpropionamidine) disulfate, 2,2'-azobis (2-methylpropionamidine) dihydrochloride , 2,2'-azobis (2-amidinopropane) dihydrochloride, 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate, 2,2'- Azo initiators, such as azobis (N, N'- dimethyl isobutyl amidine) and 2,2'- azobis [2- (2- imidazolin-2-yl) propane] dihydrochloride, For example, Persulfate-based initiators such as potassium persulfate and ammonium persulfate, such as peroxide-based initiators such as benzoyl peroxide, t-butyl hydroperoxide and hydrogen peroxide, for example, substituted ethane-based initiators such as phenyl substituted ethane, such as aromatic carbonyl Carbonyl initiators, such as a compound, For example, Redox initiators, such as the combination of a persulfate and sodium bisulfite, and the combination of a peroxide and sodium ascorbate, etc. are mentioned.

These polymerization initiators can be used alone or in combination.

Of these polymerization initiators, preferably persulfate-based initiators, more preferably ammonium persulfate are used.

Although the compounding ratio of a polymerization initiator is suitably selected, it is 0.001-1 weight part with respect to 100 weight part of reaction components, for example.

On the other hand, the dissolved oxygen concentration in the reaction component solution can be reduced by nitrogen substitution before, during or after the mixing of the polymerization initiator into the reaction component.

It does not restrict | limit especially as an emulsifier, The well-known emulsifier normally used for emulsion polymerization can be used. For example, sodium lauryl sulfate, lauryl ammonium sulfate, sodium dodecylbenzenesulfonate, polyoxyethylene sodium lauryl sulfate, polyoxyethylene alkyl ether sodium sulfate, polyoxyethylene alkyl phenyl ether ammonium sulfate, polyoxyethylene alkyl phenyl ether Anionic emulsifiers such as sodium sulfate and sodium polyoxyethylene alkylsulfosuccinate, such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene polyoxypropylene block polymer and the like Ionic emulsifiers;

Moreover, radically polymerizable (reactive) emulsifier (for example, HS-10 (Daichi Industries Co., Ltd.) which introduce | transduced radically polymerizable functional groups (reactive groups), such as a propenyl group and an allyl ether group, into these anionic emulsifiers and nonionic emulsifiers, for example. Pharmaceutical Co., Ltd.) etc. are mentioned.

These emulsifiers can be used alone or in combination. Moreover, the compounding ratio of an emulsifier is 0.2-10 weight part, Preferably it is 0.5-5 weight part with respect to 100 weight part of reaction components.

A chain transfer agent adjusts the molecular weight of a water dispersion type copolymer as needed, and can use the chain transfer agent normally used for emulsion polymerization. Examples thereof include mercaptans such as 1-dodecanethiol, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid 2-ethylhexyl, and 2,3-dimethylcapto-1-propanol.

These chain transfer agents can be used alone or in combination. In addition, the compounding ratio of a chain transfer agent is 0.001-0.5 weight part with respect to 100 weight part of reaction components, for example.

And by such emulsion polymerization, the water dispersion type copolymer obtained can be prepared as an emulsion (water dispersion).

On the other hand, a water dispersion type copolymer can also be prepared by disperse | distributing the said reaction component by the method of not using the organic solvent other than emulsion polymerization, for example, by disperse | distributing in water with the said emulsifier.

In addition, the water-dispersion type copolymer is adjusted to, for example, pH 7-9, preferably pH 7-8, for example, with ammonia water or the like for the purpose of improving the stability of the emulsion.

And the water dispersion type adhesive composition of this invention is obtained by mix | blending the water dispersion type copolymer obtained by the above, and a crosslinking agent.

As a crosslinking agent, it is a crosslinking agent which has reactivity with a carboxyl group (mainly the carboxyl group which (meth) acrylic acid has), For example, a carbodiimide type crosslinking agent, an isocyanate type crosslinking agent, an epoxy type crosslinking agent, an oxazoline type crosslinking agent, an aziridine type crosslinking agent And metal chelate crosslinking agents. As a crosslinking agent, Preferably a carbodiimide type crosslinking agent and an oxazoline type crosslinking agent are mentioned.

In addition, a crosslinking agent can use an oil-soluble or water-soluble crosslinking agent etc., or the crosslinking agent prepared as a water dispersion type (emulsion type) can also be used. As a crosslinking agent (specifically an oxazoline crosslinking agent), Preferably, a water dispersion type crosslinking agent, More preferably, a water dispersion type carbodiimide type crosslinking agent can be used.

By using the water-dispersed carbodiimide crosslinking agent as a crosslinking agent having reactivity with the carboxyl group of the water-dispersing copolymer, the physical properties of the coating solution after blending the crosslinking agent, specifically, the viscosity hardly change, and the water dispersion type in the manufacturing process Handling of the pressure-sensitive adhesive composition becomes easy.

A carbodiimide crosslinking agent is a compound which has a carbodiimide group. The carbodiimide group is a functional group without one hydrogen atom (-N = C = NH) from carbodiimide (HN = C = NH) or a functional group without two hydrogen atoms (-N = C = N-). This carbodiimide group can react with the carboxyl group.

More specifically, as a carbodiimide type crosslinking agent, the low molecular weight compound or high molecular compound which has 2 or more of carbodiimide groups is mentioned, for example.

The low molecular weight compound which has a carbodiimide group is represented by following General formula (a), for example.

[Formula a]

R ¹ -N = C = NR ² -N = C = NR ³

(Wherein R ¹ , R ² and R ³ are different from each other and represent a hydrocarbon group.)

Polymeric compounds having a carbodiimide may be mentioned a polymer compound having a polycarbodiimide, preferably high affinity for water area, for example, ethylene oxide (-CH ₂ -CH ₂ -O-) part .

The polymeric compound which has the said carbodiimide group can use what is generally marketed, for example, For example, water-soluble carbodirite V series (brand name: carbodirite V-02, carbodilite V-02-L2, carbodii) Nisshinbo Co., Ltd.), for example, the carbolight E series (brand name: carbolight light E-01, carbolight light E-02, carbolight light) of the emulsion type (water dispersion type) Nisshinbo Co., Ltd.) etc. are mentioned above.

These carbodiimide type crosslinking agents can be used individually or in combination.

Among these carbodiimide crosslinking agents, Preferably, the high molecular compound which has a carbodiimide group is mentioned.

An oxazoline type crosslinking agent is a crosslinking agent which has an oxazoline group, For example, contains the main chain which consists of an acryl skeleton or a styrene skeleton, has an oxazoline group in the side chain of the main chain, Preferably it contains the main chain which consists of an acryl skeleton And an oxazoline group-containing acrylic polymer having an oxazoline group in the side chain of the main chain thereof.

As an oxazoline group, 2-oxazoline group, 3-oxazoline group, 4-oxazoline group, etc. are mentioned, for example, Preferably a 2-oxazoline group is mentioned.

Generally as a 2-oxazoline group, it is represented by following General formula (4).

(In Formula 4, R <^12> , R <^13> , R <^14> and R <^15> respectively independently represent a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, a phenyl group, or a substituted phenyl group.)

The oxazoline group-containing polymer can also be used as an emulsion type that is emulsified with an emulsifier in water or an aqueous solution type that is dissolved in water.

As the oxazoline group-containing polymer, a general commercially available product can be used, and specifically, as an aqueous solution type, EPOCROS WS-500 (solid content 40%, main chain: acrylic, pH 7-9, oxazoline number 220 g solid / eq Oxazoline group-containing acrylic polymers such as Nippon Shokubai Co., Ltd., and epocross WS-700 (solid content 25%, main chain: acrylic, pH 7 to 9, oxazoline value 220 g solid / eq., Nippon Shokubai Co., Ltd.) For example, as an emulsion type, Epocross K-1000 series (solid content 40%, a main chain: styrene / acrylic-type, oxazoline 1100g solid / eq., PH 7-9, the Nippon Shokubai company make), Oxazoline group containing acrylic / styrene polymers, such as the Pork Ross K-2000 series (40% of solid content, a main chain: styrene / acrylic type, pH7-9, oxazoline 550g solid / eq., Nippon Shokubai company make), etc. are mentioned. Can be.

These oxazoline type crosslinking agents can be used individually or in combination of 2 or more types.

When such an oxazoline type crosslinking agent is contained in a water dispersion type adhesive composition, since an oxazoline group mainly reacts with a functional group (mainly, a carboxyl group of (meth) acrylic acid, etc.) etc. at comparatively low temperature, a firm adhesive layer can be formed.

The blending ratio of the crosslinking agent (carbodiimide crosslinking agent) is 0.07 to 4 parts by weight, preferably 0.08 to 3 parts by weight, more preferably 0.1 to 1 part by weight of 100 parts by weight of the water-dispersion copolymer (ie, the solid content of the aqueous dispersion). 2 parts by weight. In addition, when the crosslinking agent is an oxazoline-based crosslinking agent, the blending ratio is, for example, 0.07 to 1.5 parts by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of the water dispersion copolymer (ie, the solid content of the aqueous dispersion), More preferably, it is 0.1-0.3 weight part.

If it is less than the above range, the foaming of the pressure-sensitive adhesive layer in a high temperature atmosphere cannot be suppressed. On the other hand, if more than the above range, the adhesiveness (adhesiveness) of the water-dispersible pressure-sensitive adhesive composition, in particular, the adhesion to the glass substrate during heating and humidification is lowered. . On the other hand, the adhesive force at the time of heating and humidification (90 degree peeling adhesive force: peeling rate [10 mm / min]) is preferably 2.0 N / 25 mm or more.

By mix | blending this water dispersion type copolymer and a crosslinking agent, a water dispersion type copolymer is bridge | crosslinked. More specifically, when the crosslinking agent is a carbodiimide crosslinking agent, the carboxyl group of the water dispersion type copolymer reacts with the carbodiimide group of the carbodiimide crosslinking agent to crosslink the water dispersion type copolymer. When the crosslinking agent is an oxazoline crosslinking agent, the carboxyl group of the water dispersion type copolymer reacts with the oxazoline group of the oxazoline crosslinking agent to crosslink the water dispersion type copolymer.

On the other hand, after mix | blending a water dispersion type | mold copolymer and a crosslinking agent, in order to accelerate | stimulate a crosslinking reaction, you may heat, for example at 80-150 degreeC, Preferably it is 80-120 degreeC, for example for 1 to 10 minutes. In addition, this heating can also use the heating by drying at the time of formation of an adhesive layer mentioned later.

In addition, the obtained water-dispersible pressure-sensitive adhesive composition includes additives usually added to water-dispersible pressure-sensitive adhesive compositions, such as viscosity regulators, peeling regulators, plasticizers, softeners, fillers, colorants (pigments, dyes, etc.), anti-aging agents, surfactants, and the like, as necessary. You may add it suitably. The blending ratio of these additives is not particularly limited and can be selected as appropriate.

The gel fraction of the water-dispersible pressure-sensitive adhesive composition (solid content) thus prepared is, for example, 80 to 95% by weight, preferably 80 to 93% by weight. When the gel fraction is lower than the above value, foaming may occur when the water-dispersible pressure-sensitive adhesive composition is applied to the pressure-sensitive adhesive optical film and used in a high temperature atmosphere. Moreover, when a gel fraction is higher than the said value, the adhesive force of a water dispersion type adhesive composition may fall.

In addition, the gel fraction can be calculated by the following equation (2) when the water-dispersible pressure-sensitive adhesive composition is coated on a Teflon sheet (registered trademark) and immersed in ethyl acetate for 7 days.

[Equation 2]

Gel fraction (% by weight) = (weight of water-dispersible pressure-sensitive adhesive composition adhered to Teflon sheet (registered trademark) after immersion / weight of water-dispersible pressure-sensitive adhesive composition before immersion) x 100

Hereinafter, the manufacturing method of the adhesive optical film which is one Embodiment of the adhesive film of this invention is demonstrated with reference to FIG.

In order to obtain an adhesive optical film, the optical film 1 is prepared first.

The optical film 1 is not particularly limited as long as it has an optical characteristic and is a film adhered to a liquid crystal display or the like, and examples thereof include a polarizing film, a retardation film, a brightness enhancing film, a viewing angle expanding film, and the like.

As a polarizing film, what provided the transparent protective film in the one side or both sides of a polarizer can be used.

It does not restrict | limit especially as a polarizer, For example, in a hydrophilic polymer film, such as a polyvinyl alcohol-type film, a partially formalized polyvinyl alcohol-type film, and an ethylene vinyl acetate copolymer partial saponification film, it is a dichroic substance, such as iodine and a dichroic dye. And polyene-based alignment films such as those uniaxially stretched and dehydrated polyvinyl alcohol, and dehydrochloric acid treated polyvinyl chloride. Preferably, the polarizer which uniaxially stretched the polyvinyl alcohol-type film by iodine is mentioned.

Examples of the transparent protective film include polyester polymer films such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymer films such as diacetyl cellulose and triacetyl cellulose, acrylic polymer films such as polymethyl methacrylate, polystyrene and acrylo. Styrene-type polymer films, such as nitrile styrene copolymer (AS resin), a polycarbonate-type polymer film, etc. are mentioned. Further, polyolefin-based polymer films such as polyethylene, polypropylene, cyclo or norbornene structures, polyolefin-based polymer films such as ethylene-propylene copolymers, vinyl chloride-based polymer films, amide-based polymer films such as nylon and aromatic polyamides, and imide-based polymers. Film, sulfone type polymer film, polyether sulfone type polymer film, polyether ether ketone type polymer film, polyphenylene sulfide type polymer film, vinyl alcohol type polymer film, vinylidene chloride type polymer film, vinyl butyral type polymer film And an arylate polymer film, a polyoxymethylene polymer film, an epoxy polymer film, or a film of a blend of the above polymers.

The transparent protective film can also be formed as a cured layer of a thermosetting or ultraviolet curing resin such as acrylic, urethane, acrylic urethane, epoxy or silicone.

As a transparent protective film, Preferably, a cellulose polymer is mentioned. The thickness of the transparent protective film is not particularly limited and is, for example, 500 μm or less, preferably 1 to 300 μm, more preferably 5 to 200 μm.

In order to adhere | attach a polarizer and a transparent protective film, it adheres using an isocyanate adhesive, a polyvinyl alcohol adhesive, a gelatin adhesive, a vinyl adhesive, a latex adhesive, an aqueous polyester adhesive, etc., for example.

Examples of the retardation film include a birefringent film obtained by uniaxially or biaxially stretching a polymer material, an alignment film of a liquid crystal polymer, and a supporting layer of an alignment layer of a liquid crystal polymer as a film. The thickness of the retardation film is not particularly limited and is, for example, 20 to 150 µm.

Examples of the polymer material include polyvinyl alcohol, polyvinyl butyral, polymethylvinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polycarbonate, polyarylate, polysulfone, Polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, polyphenylene sulfide, polyphenylene oxide, polyallyl sulfone, polyvinyl alcohol, polyamide, polyimide, polyolefin, polyvinyl chloride, cellulose-based polymer, or their Binary, ternary, various copolymers, graft copolymers, blends and the like. These polymer materials are oriented materials (stretched films) by stretching or the like.

Examples of the liquid crystalline polymer include various main chain and side chains in which the conjugated linear atomic group (mesogen) for imparting liquid crystal alignment is introduced into the main chain or side chain of the polymer. As the main chain type liquid crystalline polymer, for example, a structure in which a mesogenic group is bonded to a spacer portion to impart flexibility, and specific examples thereof include a nematic oriented polyester liquid crystalline polymer, a discotic polymer, a cholesteric polymer, and the like. . As the side chain type liquid crystalline polymer, for example, polysiloxane, polyacrylate, polymethacrylate, or polymalonate is used as a main chain skeleton, and as the side chain, a para-substituted cyclic compound unit having a nematic orientation imparting property through a spacer portion composed of a conjugated atomic group. The thing which has a mesogenic part which consists of these is mentioned. These liquid crystalline polymers are, for example, a liquid crystalline polymer on an alignment treatment surface such as rubbing a surface of a thin film such as polyimide or polyvinyl alcohol formed on a glass plate or depositing silicon oxide on all sides. It is obtained by developing and heating the solution of.

In addition, the retardation film should just have a phase difference suitably according to what was aimed at the expansion of coloring, viewing angle, etc. by birefringence of various wavelength films and a liquid crystal layer, and other uses, for example, and laminated | stacked 2 or more types of retardation films suitably. To control optical characteristics such as retardation.

As the brightness enhancing film, for example, a multilayer thin film of a dielectric material or a multilayer laminate of thin film films having different refractive index anisotropy, the linear polarization of a predetermined polarization axis transmits and reflects other light, or an oriented film of a cholesteric liquid crystal polymer. The circular polarized light in any one of left rotation or right rotation reflects, etc. which supported this orientation liquid crystal layer on the film base material, and the other shows the characteristic which permeate | transmits.

The viewing angle magnification film is a film for widening the viewing angle so that an image is relatively clear even when the screen of the liquid crystal display is viewed from a slightly inclined direction rather than perpendicular to the screen. For example, an alignment film such as a retardation film or a liquid crystal polymer or a transparent film The thing which supported alignment layers, such as a liquid crystal polymer, on a base material is mentioned. The retardation film used as the viewing angle expanding film includes a polymer film having birefringence stretched biaxially in the plane direction, a polymer having birefringence stretched uniaxially in the plane direction and also controlled in the thickness direction stretched in the thickness direction; Bidirectional oriented films, such as a diagonal orientation film, etc. are used.

And the adhesive layer 2 which consists of a water dispersion type adhesive composition is provided in one surface of the optical film 1.

In order to provide the adhesive layer 2, the adhesive layer 2 is transferred to the optical film 1 from the release sheet 3 in which the adhesive layer 2 was formed, for example. The release sheet 3 in which the adhesive layer 2 was formed directly coats the release sheet 3 with a water-dispersible pressure-sensitive adhesive composition by a known coating method such as a knife coating method. After that, the pressure-sensitive adhesive layer 2 is provided on the release sheet 3 by, for example, heating at 80 to 150 ° C for 1 to 10 minutes and drying. In addition, in order to transfer the adhesive layer 2, after the release sheet 3 in which the adhesive layer 2 was formed was bonded to the optical film 1, the release sheet 3 is peeled off from the adhesive layer 2.

In addition, in order to provide the adhesive layer 2, the optical film 1 is directly coated by a well-known coating method, such as a knife coating method, for example, and this is 80-150 degreeC after that, for example. It may be allowed to dry for 1 to 10 minutes by heating.

In addition, as shown in FIG. 2, in order to improve the adhesive force (adhesion force) with the adhesive layer 2, the undercoat process, such as providing the undercoat layer 4 suitably, can be given to the optical film 1 previously. have.

The undercoat layer 4 contains a resin, for example, a polyacrylic resin, a polyurethane resin, a polyester resin, and the like, and the like, for example, a resin in which these resins are modified with a reactive functional group, etc. may be mentioned. Can be.

As a reactive functional group, an oxazoline group, a carboxyl group, a hydroxyl group, an amino group is mentioned, for example, Preferably an oxazoline group is mentioned.

The same thing as the above is mentioned as an oxazoline group.

As the resin modified with a reactive functional group, more specifically, for example, when the reactive functional group is an oxazoline group, it includes a main chain composed of an acrylic skeleton or a styrene skeleton, and preferably has an oxazoline group in the side chain of the main chain thereof. The same oxazoline group containing acrylic polymer is mentioned.

The number average molecular weight of an oxazoline group containing acrylic polymer is 5000 or more, for example, Preferably it is 10000 or more, Usually, 1 million or less are preferable. When the number average molecular weight is lower than 5000, the strength of the undercoat layer may be insufficient, causing cohesive failure, and the anchoring force may not be improved. When a number average molecular weight is higher than 1 million, workability may be inferior. In addition, the oxazoline group-containing acrylic polymer has an oxazoline value, such as 1500 g solid / eq. Or less, preferably 1200 g solid / eq. It is Oxazolinga 1500g solid / eq. When larger, the quantity of oxazoline group contained in a molecule | numerator may become small, and an anchoring force may not be improved.

Such resins are used alone or in combination. Such resins are usually dissolved or dispersed in an organic solvent, water, or the like, so that the blending ratio of the solid content is 0.01 to 15% by weight, preferably 0.05 to 5% by weight.

In order to provide the undercoat layer 4, the optical film 1 is directly coated with a coating method (solution or dispersion) containing a resin by a known coating method such as a coating method, a dipping method, a spray method, and dried. How to do this.

The thickness of the undercoat layer 4 is, for example, 1 to 500 µm, preferably 10 to 100 µm, more preferably 20 to 50 µm, and a thickness after drying, for example, 1 to 1000 nm. It is set to 10 to 500 nm, more preferably 20 to 400 nm.

As the release sheet 3, synthetic resin films such as paper, polyethylene, polypropylene, polyethylene terephthalate, and the like, for example, rubber sheets, cloths, nonwoven fabrics, nets, foam sheets, metal foils, or these laminated sheet bodies, may be mentioned. In order to improve the peelability from the adhesive layer 2, the surface of the release sheet 3 may be subjected to treatment (peeling treatment) such as silicon treatment, long chain alkyl treatment, and fluorine treatment as necessary.

The thickness (thickness after drying) of the adhesive layer 2 is set in the range of 1-100 micrometers, Preferably, 5-50 micrometers, More preferably, 10-30 micrometers.

The pressure-sensitive adhesive layer 2 made of the water-dispersible pressure-sensitive adhesive composition has an elongation at 90 ° C. according to the following test, 200% or less, preferably 180% or less, more preferably 150% or less, particularly preferably 100% Most preferably, it is 50% or less, and usually 0% or more.

Elongation test at 90 ° C: The water-dispersible pressure-sensitive adhesive composition is heated to prepare a pressure-sensitive adhesive layer, which is molded into a cylindrical shape having a cross-sectional area of 4.6 mm ² and a length of 30 mm to prepare a test piece. Then, the specimen is measured after left for one hour at 90 ℃, the length L ₀ of the initial test pieces. Thereafter, one end of the test piece was fixed, a 12 g weight was attached to the other end of the test piece, the test piece was hanged at 90 ° C. for 2 hours, and the length L ₁ (mm) of the test piece after the test piece was dropped for 2 hours was measured. The elongation is calculated by one.

[Equation 1]

Elongation (%) = (L ₁ -L ₀ ) / L ₀ × 100

When the elongation at 90 ° C. exceeds the above-mentioned range, the foam resistance of the pressure-sensitive adhesive layer 2 in a high temperature atmosphere decreases, and foaming cannot be suppressed.

Further, the pressure-sensitive adhesive layer 2 has an elongation at 23 ° C, for example, 150% or less, preferably 130% or less, more preferably 100% or less, particularly preferably 80% or less, most preferably 50 It is 0% or less normally.

On the other hand, the elongation degree at 23 degreeC can calculate elongation degree similarly to the said elongation test at 90 degreeC except having changed 90 degreeC into 23 degreeC in the said extension test at 90 degreeC.

Thus, the adhesive optical film can be obtained by providing the adhesive layer 2 which consists of a water dispersion type adhesive composition on one surface of the optical film 1.

The pressure-sensitive adhesive optical film thus obtained is suitably used for various industrial applications as a pressure-sensitive adhesive optical film such as a polarizing film, a retardation film, a brightness enhancement film, a viewing angle expansion film, or the like.

Since the water-dispersible adhesive composition of this invention has high adhesiveness even when it adheres to a glass substrate, an adhesive optical film can be adhere | attached firmly to a glass substrate.

Moreover, since this adhesive optical film has high heat resistance and moisture resistance, excellent durability can be obtained even in a high temperature, high humidity atmosphere.

In particular, the pressure-sensitive adhesive optical film including the pressure-sensitive adhesive layer composed of the water-dispersible pressure-sensitive adhesive composition and the water-dispersible pressure-sensitive adhesive composition of the present invention can effectively prevent the occurrence of bubbles and deformation in high temperature and high humidity. For this reason, the fall of an optical characteristic can be prevented effectively.

In addition, in the said description, although the adhesive film of this invention was demonstrated and demonstrated the adhesive optical film, it can also be used as an adhesive film adhere | attached to adherends other than an optical film. In addition, the adhesive film of this invention is used also as an adhesive sheet, an adhesive tape, etc., for example.

In addition, in the said description, although the adhesive layer 2 and the undercoat layer 4 provided as needed were provided in the one surface of the optical film 1, it can also be provided in both surfaces of the optical film 1.

On the other hand, in order to improve the adhesiveness to a to-be-adhered body as a normal water-dispersible adhesive composition, tackifying resins, such as rosin-type resin and an elastomer, are added, but the water-dispersible adhesive composition of this invention uses such a tackifying resin, although it is a water dispersion type. Since adhesiveness can be improved without adding, the adhesive film provided with the adhesive layer which consists of such a water-dispersible adhesive composition and such a water-dispersible adhesive composition which has high adhesiveness at low cost can be obtained.

Example

An Example and a comparative example are given to the following, and this invention is demonstrated more concretely. However, this invention is not limited to a following example and a comparative example at all. In addition, in the following description, "part" and "%" are a basis of weight unless there is particular notice.

Example 1

(Preparation of Monomer Emulsion)

92 parts of butyl acrylate, 6 parts of methacrylic acid, 2 parts of mono [poly (propylene oxide) methacrylate] phosphate ester (average degree of polymerization of propylene oxide of about 5.0), and 3-methacryloyloxypropyl trimethoxy 0.03 parts of silane (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) was added and mixed to prepare a mixture of reaction components. Subsequently, 46.6 g of the reactive emulsifier Akaro HS-10 (Daiichi Kogyo Pharmaceutical Co., Ltd.) and 346 g of ion-exchanged water were added to 388 g of the mixture of the prepared reaction components, using a homogenizer (manufactured by Tokushugika Co., Ltd.) For 5 minutes, it stirred at 5000 (1 / min) and forcibly emulsified, and prepared the monomer preemulsion.

(Preparation of emulsion of water dispersion copolymer)

156 g of the monomer preemulsion prepared above and 219 g of ion-exchanged water were charged to a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, followed by nitrogen substitution of the reaction vessel, and 0.023 g of ammonium persulfate (injected monomer free). 0.03 part) was added with respect to 100 parts of solid content of an emulsion, and it superposed | polymerized at 65 degreeC for 2.5 hours. Next, 0.217 g of ammonium persulfate (0.07 parts relative to 100 parts of solid content of the residual monomer preemulsion) was added to 625 g of the remaining monomer preemulsion, and this was added dropwise to the reaction vessel over 3 hours, followed by nitrogen substitution. It superposed | polymerized at 3 degreeC and obtained the emulsion (water dispersion) of the water dispersion type copolymer of 40% of solid content.

(Preparation of Water Dispersible Adhesive Composition)

The obtained emulsion was cooled to room temperature, the pH was adjusted to 8 by the addition of 10% aqueous ammonia, and the carbodiimide-based crosslinking agent (carbodiimide V-04, water-soluble type, manufactured by Nisshinbo Co., Ltd.) was further added to the solid content of the emulsion. (Water Dispersion Copolymer) 0.1 part was added to 100 parts of the water dispersion-type pressure-sensitive adhesive composition.

(Production of adhesive optical film)

The prepared water-dispersible pressure-sensitive adhesive composition was coated on a release sheet made of a polyester film treated with a release agent, and heated and dried at 100 ° C. for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 23 μm.

Moreover, the polarizing film which processed the undercoating beforehand was prepared. First, as an undercoating treatment, an oxazoline group-containing acrylic polymer (Epocross WS-700, manufactured by Nihon Shokubai Co., Ltd.) is diluted in a mixed solvent of water and ethanol (1: 1 by volume ratio) so that the solid content is 0.25% by weight. One primer solution was prepared. Subsequently, this undercoating solution was applied to one side of the polarizing film using wire bar # 5, and the undercoating layer was prepared by heating and drying at 40 ° C for 2 minutes.

In addition, the said polarizing film was produced by extending | stretching a polyvinyl alcohol film in the iodine aqueous solution, and after drying, attaching a triacetyl cellulose film as a transparent protective film to both sides of this polarizer.

Subsequently, this polarizing film was laminated | stacked so that the surface and the retardation film which are not provided with the undercoat layer were bonded on retardation film (NAZ- # 195-0.3, the Nitto Denko Co., Ltd. product). Thereby, the optical film in which the polarizing film with which the undercoat layer was provided, and the retardation film were laminated | stacked was produced.

Next, the adhesive layer was laminated | stacked on the undercoat layer of the optical film, and the adhesive optical film was produced (refer FIG. 2).

Example 2

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 1, 0.3 part of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.1 part of carbodiimide-based crosslinking agent (carbodiide V-04). A water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 1 except that a pressure-sensitive adhesive optical film was then produced.

Example 3

(Preparation of Monomer Emulsion)

In a container, 88 parts of butyl acrylate, 5 parts of acrylic acid, 5 parts of cyclohexyl methacrylate, 2 parts of mono [poly (propylene oxide) methacrylate] phosphate ester (average degree of polymerization of propylene oxide about 5.0), and 3-methacryl 0.03 parts of yloxypropyl-trimethoxysilane (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) was added and mixed to prepare a mixture of reaction components. Subsequently, 46.6 g of the reactive emulsifier Akaro HS-10 (Daiichi Kogyo Pharmaceutical Co., Ltd.) and 346 g of ion-exchanged water were added to 388 g of the prepared reaction component mixture, using a homogenizer (manufactured by Tokushugika Co., Ltd.). For 5 minutes, it stirred at 5000 (1 / min) and forcibly emulsified, and prepared the monomer preemulsion.

(Preparation of emulsion of water dispersion copolymer)

Into a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, 78 g of the monomer preemulsion prepared above and 219 g of ion-exchanged water were charged, followed by nitrogen substitution of the reaction vessel, followed by 0.004 g of ammonium persulfate (filled 0.01 part) with respect to 100 parts of solid content of a monomer free emulsion was added, and it superposed | polymerized at 65 degreeC for 2.5 hours. Subsequently, 0.244 g of ammonium persulfate (0.07 parts relative to 100 parts of solid content of the residual monomer preemulsion) was added to 702.5 g of the remaining monomer preemulsion, and this was added dropwise to the reaction vessel over 3 hours. It superposed | polymerized at 75 degreeC for 3 hours, replacing by nitrogen, and obtained the emulsion (water dispersion) of the water dispersion type copolymer of 40% of solid content.

(Preparation of Water Dispersible Adhesive Composition)

The obtained emulsion was cooled to room temperature, the pH was adjusted to 8 by the addition of 10% aqueous ammonia, and the carbodiimide-based crosslinking agent (carbodirite V-04) was also added to 100 parts of the solids (water dispersion copolymer) of the emulsion. 0.5 part was added and the water dispersion type adhesive composition was prepared.

(Production of adhesive optical film)

The prepared water-dispersible pressure-sensitive adhesive composition was coated on a release sheet made of a polyester film treated with a release agent, and heated at 100 ° C. for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 23 μm.

Next, the adhesive layer was laminated | stacked on the undercoat layer of the optical film similar to Example 1, and the adhesive optical film was produced (refer FIG. 2).

Example 4

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 1 part of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.5 part of carbodiimide-based crosslinking agent (carbodiide V-04). And the water dispersion type adhesive composition was prepared by the method similar to Example 3, and the adhesive optical film was produced continuously.

Example 5

In preparation of the emulsion of the water-dispersion copolymer in Example 3, ammonium persulfate 0.175 instead of 0.244 g of ammonium persulfate (0.07 parts relative to 100 parts of solid content of the remaining monomer-free emulsion) in the dropwise polymerization. An emulsion (water dispersion) of a water-dispersion copolymer was prepared in the same manner as in Example 3 except that g (0.05 parts relative to 100 parts of the solid content of the monomer-free emulsion of the remainder) was added, and then a water-dispersible pressure-sensitive adhesive composition was prepared. Then, the adhesive optical film was produced.

Example 6

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 1 part of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.5 part of carbodiimide-based crosslinking agent (carbodiide V-04). And the water dispersion type adhesive composition was prepared by the method similar to Example 3, and the adhesive optical film was produced continuously.

Example 7

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, except that 0.5 parts of carbodiimide-based crosslinking agent (carbodiide V-04) was added, 2 parts of carbodiimide-based crosslinking agent (carbodirite V-04) was added. And the water dispersion type adhesive composition was prepared by the method similar to Example 3, and the adhesive optical film was produced continuously.

Example 8

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 3 parts of carbodiimide-based crosslinking agent (carbodilite V-04) were added instead of 0.5 parts of carbodiimide-based crosslinking agent (carbodiide V-04). And the water dispersion type adhesive composition was prepared by the method similar to Example 3, and the adhesive optical film was produced continuously.

Example 9

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, in place of 0.5 parts of carbodiimide-based crosslinking agent (carbodiilite V-04), carbodiimide-based crosslinking agent (carbodiilite E-04, emulsion type, Nisshinbo A water dispersion-type adhesive composition was prepared by the method similar to Example 3 except having added 1 part of (co., Ltd. products), and the adhesive optical film was produced continuously.

Example 10

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, in place of 0.5 parts of carbodiimide-based crosslinking agent (carbodiilite V-04), carbodiimide-based crosslinking agent (carbodiilite E-04, emulsion type, Nisshinbo A water dispersion-type adhesive composition was prepared by the method similar to Example 3 except having added 0.5 part of (co., Ltd. products), and the adhesive optical film was produced continuously.

Example 11

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, in place of 0.5 parts of carbodiimide-based crosslinking agent (carbodiilite V-04), carbodiimide-based crosslinking agent (carbodiilite E-04, emulsion type, Nisshinbo A water dispersion-type adhesive composition was prepared by the method similar to Example 3 except having added 2 parts of (manufactured), and the adhesive optical film was produced continuously.

Comparative Example 1

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 1, except that no carbodiimide-based crosslinking agent was added, the water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 1, and then a pressure-sensitive adhesive optical film was produced. did.

Comparative Example 2

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, a water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 3 except that no carbodiimide-based crosslinking agent was added, and then a pressure-sensitive adhesive optical film was produced. .

Comparative Example 3

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 0.0005 part of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.1 part of carbodiimide-based crosslinking agent (carbodiide V-04). And the water dispersion type adhesive composition was prepared by the method similar to Example 3, and the adhesive optical film was produced continuously.

Comparative Example 4

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 0.001 part of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.5 part of carbodiimide-based crosslinking agent (carbodiirite V-04). A water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 3 except that a pressure-sensitive adhesive optical film was then produced.

Comparative Example 5

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 0.05 part of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.5 part of carbodiimide-based crosslinking agent (carbodiide V-04). A water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 3 except that a pressure-sensitive adhesive optical film was then produced.

Comparative Example 6

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 3, 5 parts of carbodiimide-based crosslinking agent (carbodilite V-04) was added instead of 0.5 parts of carbodiimide-based crosslinking agent (carbodiide V-04). A water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 3 except that a pressure-sensitive adhesive optical film was then produced.

(evaluation)

1) Elongation of the adhesive layer

The 23-micrometer-thick adhesive layer was prepared by heating the water dispersion type adhesive composition in Examples 1-11 and Comparative Examples 1-6 for 2 minutes at 100 degreeC, respectively. After cooling the adhesive layer, it shape | molded in the shape of the flat rectangular sheet of 200 mm x 30 mm with a spatula. Next, by winding this by hand, it shape | molded to the cylindrical shape of cross-sectional area 4.6mm <^2> , length 30mm, and produced the test piece. Subsequently, 10 mm portions at both ends in the longitudinal direction of the test piece were sandwiched with clips, respectively. And it left to stand for 1 hour in 23 degreeC (room temperature) and 90 degreeC atmosphere, and hardened the test piece.

Then, measured is not installed in the middle of the clip that is the longitudinal length (length of the initial) L ₀ (mm) in advance as in the test piece. Subsequently, the clip of one end of the test piece was fixed, and 12 g of weight was attached to the clip of the other end of the test piece, and the test piece was hanged for 2 hours in the atmosphere of 23 degreeC (room temperature) and 90 degreeC. After 2 hours in pendent, each test piece was measured for the length L ₁ (mm) of the medium is not fixed longitudinally to the clip letter in the. On the other hand, the initial length L ₀ is about 10 mm.

And the elongation of 2 hours at 23 degreeC, and the elongation of 2 hours at 90 degreeC were computed from following Formula (1), respectively. The results are shown in Table 1.

[Equation 1]

Elongation (%) = (L ₁ -L ₀ ) / L ₀ × 100

2) Gel fraction

The water-dispersible pressure-sensitive adhesive compositions (about 100 mg) of Examples 1 to 11 and Comparative Examples 1 to 6 were first wrapped with a pre-weighed Teflon sheet (registered trademark part number: NTF-1122) and twisted yarn (12 cm), and the wrapped package was The weight was measured. Subsequently, this package was put into a 50 ml glass bottle, then ethyl acetate was sufficiently added, the glass bottle was sealed, and immersed at room temperature for 7 days. Thereafter, the immersed package was taken out, and the ethyl acetate adhered to the Teflon sheet (registered trademark) was wiped off, and the package was dried in a dryer at 130 ° C. for 2 hours. Then, the package after drying was weighed. And the gel fraction was computed by following formula (3).

[Equation 3]

Gel fraction (% by weight) = {(C-A) / (B-A)} × 100

In addition, the detail of the symbol in a formula is as follows.

A (g): Teflon sheet (registered trademark) and total weight of twisted yarn (weight of outer packaging)

B (g): Teflon sheet (registered trademark) and twisted yarn, ethyl acetate immersion with water-dispersible adhesive composition, total weight before drying

C (g): Teflon sheet (registered trademark) and twisted yarn, total weight after immersion of ethyl acetate in water-dispersible pressure-sensitive adhesive composition and drying

The results are shown in Table 1.

3) glass adhesive

The adhesive optical film obtained by Examples 1-11 and Comparative Examples 1-6 was cut | disconnected to width 25mm, this was adhere | attached on the glass plate (Corning # 1737, Corning Corporation make), and 2 kg rubber rollers were reciprocated 1 time. It was crimped | bonded, it was left to stand in 50 degreeC and a 0.5 MPa autoclave for 15 minutes, Then, it cooled to 25 degreeC, and measured the 90 degree peeling adhesive force (peel rate 10 mm / min) (initial adhesive force).

Furthermore, after being left in the autoclave, the mixture was left for 40 hours in an atmosphere of 60 ° C. and 60 ° C./90% RH, and then cooled to 25 ° C. to obtain 90 ° peeling strength (peel rate 10 mm / min). Each was measured. The results are shown in Table 1.

On the other hand, glass adhesiveness shows that it is so favorable that the value of peeling adhesive force is high.

4) Heating foam of adhesive optical film

The adhesive optical films of Examples 1-11 and Comparative Examples 1-6 were cut | disconnected to the magnitude | size of width 235mm x length 310mm, and this was adhere | attached on the glass plate (Corning # 1737, Corning Corporation make) of thickness 0.7mm. Then, it was left to stand in 50 degreeC and 0.5 MPa autoclave for 15 minutes, and was left to stand for 500 hours in the atmosphere heated at 90 degreeC. Then, the presence or absence of foaming of the adhesive optical film was observed visually.

In addition, the presence or absence of foaming in an adhesive optical film was observed on the following reference | standard.

○: No foaming was found

△: foaming was found slightly

×: foaming was found

The abbreviation of Table 1 is shown below.

PAM-200: Sipomer PAM-200 (mono [poly (propylene oxide) methacrylate] phosphate ester (average degree of polymerization of propylene oxide of about 5.0), Rodier Nikka Co., Ltd.)

KBM-503: 3-methacryloyloxypropyl-trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)

HS-10: Reactive emulsifier Akaro HS-10 (Daiichi Kogyo Pharmaceutical Co., Ltd.)

V-04: carbodiimide-based crosslinking agent (carbodilite V-04, water-soluble type, manufactured by Nisshinbo Co., Ltd.)

E-04: carbodiimide-based crosslinking agent (carbodiilite E-04, emulsion type, manufactured by Nisshinbo Co., Ltd.)

Example 12

(Preparation of Monomer Emulsion)

88 parts of butyl acrylate, 5 parts of acrylic acid, cyclohexyl methacrylate, 5 parts of mono [poly (propylene oxide) methacrylate] phosphate ester (average degree of polymerization of propylene oxide about 5.0, Sipomer PAM-200, rodiert 2 parts of CASA) and 0.03 parts of 3-methacryloyloxypropyl trimethoxysilane (KBM-503, Shin-Etsu Chemical Co., Ltd. product) were added and mixed, and the reaction component was prepared. Subsequently, 46.6 g of the reactive emulsifier Akaro HS-10 (Daiichi Kogyo Pharmaceutical Co., Ltd.) and 109 g of ion-exchanged water were added to 388 g of the prepared reaction component, and it was 5000 for 5 minutes using a homogenizer (manufactured by Tokushugika Co., Ltd.). It stirred at (1 / min) and forcibly emulsified and prepared the monomer preemulsion.

(Preparation of emulsion of water dispersion copolymer)

To a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, 54 g of the monomer preemulsion prepared above and 456 g of ion-exchanged water were added thereto, followed by nitrogen substitution of the reaction vessel, and 0.3 g of ammonium persulfate was added thereto. It polymerized at 65 degreeC for 2.5 hours. Subsequently, 489.6 g of the remainder of the monomer preemulsion was dropped in the reaction vessel over 3 hours, and then polymerized for 3 hours. Then, it superposed | polymerized at 75 degreeC for 3 hours, carrying out nitrogen substitution, and obtained the emulsion (water dispersion) of the water dispersion type copolymer of 40% of solid content.

(Preparation of Water Dispersible Adhesive Composition)

The obtained emulsion was cooled to room temperature, pH was adjusted to 8 by adding 10% ammonia water, and an oxazoline crosslinking agent (epoxrose WS-700, an oxazoline group-containing acrylic polymer, aqueous solution type, manufactured by Nihon Shokubai Co., Ltd.) was prepared. Furthermore, 0.1 part was added with respect to 100 parts of solid content (water dispersion type copolymer) of an emulsion, and the water dispersion type adhesive composition was prepared.

(Production of adhesive optical film)

The prepared water-dispersible pressure-sensitive adhesive composition was coated on a release sheet made of a polyester film treated with a release agent, and heated and dried at 100 ° C. for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 23 μm.

Moreover, the polarizing film which processed the undercoating beforehand was prepared. As the undercoat treatment, first, an oxazoline group-containing acrylic polymer (Epocross WS-700, manufactured by Nihon Shokubai Co., Ltd.) was diluted in a mixed solvent of water and ethanol (1: 1 by volume ratio) so that the solid content was 2% by weight. The solution was prepared. Subsequently, this undercoating solution was applied to one side of the polarizing film using wire bar # 5, and the undercoating layer was prepared by heating and drying at 40 ° C for 2 minutes.

On the other hand, the said polarizing film was produced by extending | stretching a polyvinyl alcohol film in the iodine aqueous solution, and after drying, adhering a triacetyl cellulose film as a transparent protective film to both sides of this polarizer.

Subsequently, this polarizing film was laminated on the retardation film (NAZ- # 195-0.3, manufactured by Nitto Denko) so that the surface on which the undercoat layer was not provided and the retardation film were bonded together. This produced the optical film in which the polarizing film with which the undercoat layer was provided, and the retardation film were laminated | stacked.

Next, the pressure-sensitive adhesive layer was laminated on the undercoat layer of the optical film to prepare a pressure-sensitive adhesive optical film (see FIG. 2).

Example 13

In preparation of the water-dispersible adhesive composition in Example 12, an oxazoline type crosslinking agent instead of 0.1 part of oxazoline type crosslinking agents (epoxrose WS-700, an oxazoline group containing acrylic polymer, aqueous solution type, the Nippon Shokubai company make) (Epocross WS-700, an oxazoline group-containing acrylic polymer, an aqueous solution type, manufactured by Nippon Shokubai Co., Ltd.), except that 0.3 parts were added, a water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 12, and subsequently, an adhesive type An optical film was produced.

Example 14

In preparation of the water-dispersible adhesive composition in Example 12, an oxazoline type crosslinking agent instead of 0.1 part of oxazoline type crosslinking agents (epoxrose WS-700, an oxazoline group containing acrylic polymer, aqueous solution type, the Nippon Shokubai company make) (Epocross WS-700, an oxazoline group-containing acrylic polymer, an aqueous solution type, manufactured by Nippon Shokubai Co., Ltd.), except that one part was added, a water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 12, and subsequently, an adhesive type An optical film was produced.

Comparative Example 7

In preparation of the water-dispersible adhesive composition in Example 12, an oxazoline type crosslinking agent instead of 0.1 part of oxazoline type crosslinking agents (epoxrose WS-700, an oxazoline group containing acrylic polymer, aqueous solution type, the Nippon Shokubai company make) (Epocross WS-700, an oxazoline group-containing acrylic polymer, an aqueous solution type, manufactured by Nihon Shokubai Co., Ltd.) A water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 12, except that 0.001 part was added. An optical film was produced.

Comparative Example 8

In preparation of the water-dispersible adhesive composition in Example 12, an oxazoline type crosslinking agent instead of 0.1 part of oxazoline type crosslinking agents (epoxrose WS-700, an oxazoline group containing acrylic polymer, aqueous solution type, the Nippon Shokubai company make) (Epocross WS-700, an oxazoline group-containing acrylic polymer, an aqueous solution type, manufactured by Nippon Shokubai Co., Ltd.), except that 0.05 part was added, a water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 12, and subsequently, an adhesive type An optical film was produced.

Comparative Example 9

In preparation of the water-dispersible adhesive composition in Example 12, an oxazoline type crosslinking agent instead of 0.1 part of oxazoline type crosslinking agents (epoxrose WS-700, an oxazoline group containing acrylic polymer, aqueous solution type, the Nippon Shokubai company make) A water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 12, except that 2 parts (Epocross WS-700, an oxazoline group-containing acrylic polymer, an aqueous solution type, manufactured by Nippon Shokubai Co., Ltd.) were added, and then, A type optical film was produced.

Comparative Example 10

In the preparation of the water-dispersible pressure-sensitive adhesive composition in Example 12, a water-dispersible pressure-sensitive adhesive composition was prepared in the same manner as in Example 12 except that no oxazoline-based crosslinking agent was added, and then a pressure-sensitive adhesive optical film was produced. .

(evaluation)

5) Elongation of the adhesive layer

About the water dispersion type adhesive composition in Examples 12-14 and Comparative Examples 7-10, the elongation of 2 hours at 23 degreeC, and the elongation of 2 hours at 90 degreeC was calculated by the same method as the above, respectively. . The results are shown in Table 2.

6) Gel fraction

The gel fraction of the water dispersion type adhesive composition of Examples 12-14 and Comparative Examples 7-10 was computed by the above method. The results are shown in Table 2.

7) glass adhesive

About the adhesive optical film obtained by Examples 12-14 and Comparative Examples 7-10, the 90 degree peeling adhesive force (peel rate 10 mm / min) was measured by the above method, respectively. The results are shown in Table 2.

8) Heating foam of adhesive optical film

About the adhesive optical film of Examples 12-14 and Comparative Examples 7-10, the presence or absence of foaming was observed by the method similar to the above.

The symbol of Table 2 is shown below.

PAM-200: Sipomer PAM-200 (mono [poly (propylene oxide) methacrylate] phosphate ester (average degree of polymerization of propylene oxide of about 5.0), Rodier Nikka Co., Ltd.)

KBM-503: 3-methacryloyloxypropyl-trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)

Epocross WS-700: An oxazoline group-containing acrylic polymer (aqueous solution type, solid content 25%, main chain: acrylic, pH 7-9, oxazoline value 220 g solid / eq., Manufactured by Nihon Shokubai Co., Ltd.)

In addition, although the said description was provided as embodiment of an illustration of this invention, this is only a mere illustration and should not interpret it limitedly. Modifications of the invention which are apparent to those skilled in the art are included in the later claims.

1 is an enlarged cross-sectional view of a pressure-sensitive adhesive optical film of one embodiment of the pressure-sensitive adhesive film of the present invention;

2 is an enlarged cross-sectional view of a pressure-sensitive adhesive optical film that is another embodiment of the pressure-sensitive adhesive film of the present invention.

Claims (7)

A water-dispersed copolymer obtained by reacting a reaction component containing a (meth) acrylic acid alkyl ester having 4 to 18 carbon atoms and having a linear or branched alkyl group, (meth) acrylic acid, a phosphoric acid group-containing vinyl monomer and an alkoxysilyl group-containing vinyl monomer ; And A water-dispersible pressure-sensitive adhesive composition containing a crosslinking agent having reactivity with a carboxyl group, The compounding ratio of the said crosslinking agent is 0.07-4 weight part with respect to 100 weight part of said water dispersion type copolymers, The pressure-sensitive adhesive layer composed of the water-dispersible pressure-sensitive adhesive composition has an elongation of 200% or less at 90 ° C. according to the following test. Test: The water-dispersible pressure-sensitive adhesive composition is heated to prepare a pressure-sensitive adhesive layer, which is molded into a cylindrical shape having a cross-sectional area of 4.6 mm ² and a length of 30 mm to prepare a test piece. Then, the specimen is measured after left for one hour at 90 ℃, the length L ₀ of the initial test pieces. Thereafter, one end of the test piece was fixed, a 12 g weight was attached to the other end of the test piece, the test piece was hanged at 90 ° C. for 2 hours, and the length L ₁ (mm) of the test piece after the test piece was dropped for 2 hours was measured. The elongation is calculated by one. [Equation 1] Elongation (%) = (L ₁ -L ₀ ) / L ₀ × 100 The method of claim 1, The said crosslinking agent is a compound which has a carbodiimide group, The water dispersion type adhesive composition characterized by the above-mentioned. The method of claim 1, The crosslinking agent is a crosslinking agent having an oxazoline group, Water-dispersible pressure-sensitive adhesive composition, characterized in that the blending ratio of the crosslinking agent is 0.07 to 1.5 parts by weight based on 100 parts by weight of the water-dispersion copolymer. The method of claim 1, The water dispersion type pressure-sensitive adhesive composition is a water dispersion type pressure-sensitive adhesive composition, characterized in that the gel fraction when immersed in ethyl acetate is 80 to 95% by weight. It is provided with the adhesive layer which consists of water dispersion type adhesive compositions, The water-dispersible pressure-sensitive adhesive composition contains a reaction component containing a (meth) acrylic acid alkyl ester, a (meth) acrylic acid, a phosphoric acid group-containing vinyl monomer and an alkoxysilyl group-containing vinyl monomer having 4 to 18 carbon atoms and having a linear or branched alkyl group. Water-dispersible copolymer obtained by reacting; And A crosslinking agent having reactivity with a carboxyl group, The compounding ratio of the said crosslinking agent is 0.07-4 weight part with respect to 100 weight part of said water dispersion type copolymers, The pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is characterized in that the elongation at 90 ℃ by the following test 200% or less. Test: The water-dispersible pressure-sensitive adhesive composition is heated to prepare a pressure-sensitive adhesive layer, which is molded into a cylindrical shape having a cross-sectional area of 4.6 mm ² and a length of 30 mm to prepare a test piece. Then, the specimen is measured after left for one hour at 90 ℃, the length L ₀ of the initial test pieces. Thereafter, one end of the test piece was fixed, a 12 g weight was attached to the other end of the test piece, the test piece was hanged at 90 ° C. for 2 hours, and the length L ₁ (mm) of the test piece after the test piece was dropped for 2 hours was measured. The elongation is calculated by one. [Equation 1] Elongation (%) = (L ₁ -L ₀ ) / L ₀ × 100 The method of claim 5, wherein The said crosslinking agent is a compound which has a carbodiimide group, The adhesive film characterized by the above-mentioned. The method of claim 5, wherein The crosslinking agent is a crosslinking agent having an oxazoline group, The compounding ratio of the said crosslinking agent is 0.07-1.5 weight part with respect to 100 weight part of said water dispersion type copolymers.

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