KR20050076819A - Adhesive composition for optical members, adhesive layer for optical members, adhesive sheet for optical members, and optical members - Google Patents

Abstract

The optical member which can prevent the lifting and peeling by the change of temperature and humidity environment, and is excellent in durability, such as heat resistance and moisture resistance, and can peel easily even after preservation for a long time after adhesion of an optical component, or in high temperature, high humidity atmosphere. Optical pressure-sensitive adhesive sheet, the pressure-sensitive adhesive sheet for optical members having the pressure-sensitive adhesive layer for optical members, the pressure-sensitive adhesive composition for optical members for obtaining the pressure-sensitive adhesive layer for optical members, and the pressure-sensitive adhesive layer for optical members are provided on the optical component. To provide the member, 100 parts by weight of an acrylic polymer emulsion obtained by emulsion polymerization of a monomer mixture containing 80% by weight or more of (meth) acrylic acid ester, an emulsion containing a reactive emulsifier and a polymerization initiator, and a solid content of the acrylic polymer emulsion To prepare an adhesive composition for an optical member containing 0.01 to 1 part by weight of the silane coupling agent And coating and drying this on the substrate to give an adhesive layer for an optical member.

Description

Adhesive composition for optical members, adhesive layer for optical members, adhesive sheet for optical members, and optical member {ADHESIVE COMPOSITION FOR OPTICAL MEMBERS, ADHESIVE LAYER FOR OPTICAL MEMBERS, ADHESIVE SHEET FOR OPTICAL MEMBERS, AND OPTICAL MEMBERS}

The present invention relates to an adhesive composition for an optical member, an adhesive layer for an optical member, an adhesive sheet for an optical member, and an optical member, and specifically, an adhesive composition for an optical member for adhering optical components such as a polarizing plate, a retardation plate, an elliptical polarizing plate, and the like. The present invention relates to an optical member having an optical component, an adhesive layer for an optical member, an adhesive sheet for an optical member, and an adhesive layer for the optical member.

Optical components used for liquid crystal display devices, such as a flat display panel, for example, a polarizing plate and a retardation plate, are adhere | attached on a liquid crystal cell using an adhesive. Since the adhesive used for such a use is normally stretched by the change of temperature-humidity environment, and lifting or peeling with respect to the liquid crystal cell of an optical component tends to occur easily, the durability which can respond | corresponds is calculated | required.

In addition, in the case of tackiness or positional shift at the time of adhesion, the optical component is peeled from the liquid crystal cell to reuse the liquid crystal cell, but the adhesive can be easily used without changing or breaking the gap of the liquid crystal cell during this peeling. It is required to be able to peel. Therefore, it is required for the adhesive used for such a use to improve the re-peelability at the time of peeling, also improving adhesive force and improving durability.

In addition, since the optical component has a dimensional change due to a change in temperature and humidity environment, and internal stress is generated thereby, the pressure sensitive adhesive uniformly relieves such internal stress so that residual stress does not remain in the optical component. It is also desired to prevent color unevenness or white omission resulting from such residual stress.

Conventionally, the organic adhesive type acrylic adhesive is used for such a use. However, such an organic solvent type acrylic pressure sensitive adhesive is environmentally unfavorable since the organic solvent is acidified during coating, and thus, the conversion to an aqueous type acrylic pressure sensitive adhesive has recently been planned.

For example, a pressure-sensitive adhesive sheet in which a water-dispersible pressure-sensitive adhesive composed of an aqueous mixture obtained by emulsion polymerization of a monomer mixture containing alkyl (meth) acrylate ester and a silane-based monomer as an adhesive layer is provided on at least one side of a support as an adhesive layer. The adhesive sheet for glass plates containing 0.005-1 weight part of silane-based monomers with respect to parts, and whose adhesive force after 7 days storage at 70 degreeC and 20% RH after adhesion to a glass plate adherend is 1.3 times or more of an initial value, As an optical film as a support body It is proposed to produce a pressure-sensitive adhesive optical film for glass substrate adhesion of a liquid crystal panel using, for example, Japanese Unexamined Patent Application Publication No. 2002-309212.

However, also in the adhesive sheet for glass plates described in Unexamined-Japanese-Patent No. 2002-309212, it is difficult to fully satisfy all the above-mentioned physical properties, such as durability and re-peelability required for such use.

An object of the present invention is to prevent the lifting and peeling due to the physical properties necessary for the adhesion of the optical component, that is, the temperature and humidity environment, and excellent durability, such as heat resistance and moisture resistance, and after the adhesion of the optical component, after a long time or high temperature The pressure-sensitive adhesive layer for an optical member for obtaining the pressure-sensitive adhesive layer for an optical member, the pressure-sensitive adhesive sheet for an optical member having the pressure-sensitive adhesive layer for the optical member, and the pressure-sensitive adhesive layer for the optical member, which can be easily peeled off even when stored in a high humidity atmosphere. And it is providing the optical member with which the adhesion layer for optical members is equipped in the optical component.

The adhesive composition for an optical member of the present invention is an acrylic polymer emulsion obtained by emulsion polymerization of a monomer mixture containing 80% by weight or more of (meth) acrylic acid ester, a reactive emulsifier containing a radical polymerizable functional group and an emulsion containing a polymerization initiator, And 0.01 to 1 part by weight of the silane coupling agent based on 100 parts by weight of the solid content of the acrylic polymer emulsion.

Moreover, this invention contains the adhesive layer for optical members which consists of said adhesive composition for optical members.

Moreover, this invention includes the adhesive sheet for optical members provided with said adhesive layer for optical members.

Moreover, it is preferable that the said adhesive sheet for optical members adheres to glass, and the adhesive force with respect to the said glass after 17 hours has elapsed at 60 degreeC is 10 N / 25 mm or less.

Moreover, this invention includes the optical member with which the said adhesive layer for optical members is equipped in one side or both sides of an optical component.

Moreover, it is preferable that the said optical component is any one of a polarizing plate, a retardation plate, and an elliptical polarizing plate.

Description of the Preferred Embodiments

The adhesive composition for optical members of this invention contains the acrylic polymer emulsion and a silane coupling agent.

Acrylic polymer emulsions can be obtained by emulsion polymerizing an emulsion comprising a monomer mixture, a reactive emulsifier and a polymerization initiator.

In the present invention, the monomer mixture contains 80% by weight or more of (meth) acrylic acid ester.

Examples of the (meth) acrylic acid ester include methacrylic acid ester and / or acrylic acid ester, and examples thereof include a compound represented by the following general formula (1).

CH ₂ = CR1COOR2

Where

R1 represents hydrogen or a methyl group,

R2 represents a linear or branched alkyl group having 1 to 18 carbon atoms.

As R2, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group, neopentyl group, isoamyl group, hexyl group, heptyl group, jade And a methyl group, isooctyl group, 2-ethylhexyl group, isononyl group, decyl group, isodecyl group, lauryl group, carbonyl group, isobornyl group, myristyl group, pentadecyl group, stearyl group and the like. .

More specifically, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate and sec-methacrylate (meth) acrylate Butyl, t-butyl (meth) acrylate, pentyl (meth) acrylate, neopentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, ( 2-ethylhexyl methacrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, carbonyl (meth) acrylate, Isobornyl acrylate, myristyl (meth) acrylate, pentadecyl (meth) acrylate, stearyl (meth) acrylate, and the like.

These (meth) acrylic acid esters are used alone or in combination as appropriate. Moreover, these (meth) acrylic acid esters contain 80 weight% or more with respect to a monomer mixture, Preferably it is 85-99.5 weight%. When content of the (meth) acrylic acid ester is less than 80 weight%, the adhesive force to glass may become large too much.

In addition to the (meth) acrylic acid ester, the monomer mixture may contain a monomer copolymerizable with the (meth) acrylic acid ester.

As such a copolymerizable monomer, the functional group containing monomer containing a functional group, the silane type monomer containing a silicon atom, etc. are mentioned, for example.

As the functional group-containing monomer, for example, a carboxyl group-containing monomer such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, crotonic acid, maleic anhydride or an acid anhydride thereof, such as (meth) acrylic acid-2-hydroxyethyl, (meth) Hydroxyl group-containing monomers such as 2-hydroxypropyl acrylate and 2-hydroxybutyl (meth) acrylate, such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methylol ( Amide group-containing monomers such as meth) acrylamide, N-methoxymethyl (meth) acrylamide, and N-butoxymethyl (meth) acrylamide, such as (meth) acrylic acid dimethylaminoethyl and (meth) acrylic acid t-butyl Amino group-containing monomers such as aminoethyl, for example, glycidyl group-containing monomers such as glycidyl (meth) acrylate, other (meth) acrylonitrile, N- (meth) acryloyl morpholine, and N-vinyl-2-pi Lollydon and so on Can be mentioned.

These functional group containing monomers are used suitably individually or in combination. Further, these functional group-containing monomers are contained in less than 20% by weight, preferably 0.47 to 14.9% by weight relative to the monomer mixture.

Moreover, as a silane monomer, the silane monomer which has (meth) acryloyl groups, such as the (meth) acryloyloxyalkylsilane derivative excellent in the copolymerizability with respect to (meth) acrylic acid ester, is mentioned, for example. Examples of such silane monomers include 3-methacryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, and 3- Acryloyloxypropyltriethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldi Ethoxysilane, vinyl trimethoxy silane, vinyl triethoxy silane, 4-vinyl butyl trimethoxy silane, 4-vinyl butyl triethoxy silane, 8-vinyl octyl trimethoxy silane Phosphorus, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltrie Oxysilane, 10-acryloyloxydecyltriethoxy silane And the like.

These silane monomers are suitably used alone or in combination. In addition, these silane-based monomers are contained, for example, 0.005 to 1% by weight, preferably 0.01 to 0.5% by weight, more preferably 0.03 to 0.1% by weight based on the monomer mixture. If it is less than 0.005 weight%, polymer strength may run short and cohesion force may fall. Moreover, when it exceeds 0.1 weight%, adhesive force may fall to the extent to which it cannot adhere | attach.

In the present invention, first, a monomer copolymerizable with the above-mentioned (meth) acrylic acid ester and (meth) acrylic acid ester is suitably blended as a monomer mixture, and a reactive emulsifier and water are added thereto, followed by emulsification to prepare an emulsion. Subsequently, emulsion polymerization is carried out by adding a polymerization initiator and water to the emulsion as necessary.

The reactive emulsifier is, for example, an emulsifier into which radical polymerizable functional groups such as propenyl group and allyl ether group are introduced, and more specifically, acryon HS-10, HS-20, KH-10, BC-05, BC-10, BC -20 (made by Daiichi Kogyo Pharmaceutical Co., Ltd.), for example, Adecaria soap SE10N (made by Asahi Denka Kogyo Co., Ltd.), etc. are mentioned.

By using such a reactive emulsifier, the heat resistance and moisture resistance can be improved.

In addition, these reactive emulsifiers are used alone or in combination as appropriate. The proportion of these reactive emulsifiers is, for example, 0.2 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the monomer mixture (corresponding to 100 parts by weight of the solid content of the acrylic polymer emulsion described later. .

The emulsion can be prepared, for example, by adding a monomer copolymerizable with the above-mentioned (meth) acrylic acid ester or a (meth) acrylic acid ester in water as a monomer mixture, and simultaneously adding a reactive emulsifier in water, followed by stirring and mixing. .

Thereafter, the emulsion is polymerized by adding a polymerization initiator and water to the emulsion as necessary.

The polymerization initiator is preferably a known radical polymerization initiator which is usually used as a polymerization initiator in emulsion polymerization. For example, 2,2'-azobisisobutyronitrile and 2,2'-azobis (2-methylpropionamidine) Disulfate, 2,2'-azobis (2-amidinopropane) dihydrochloride, 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] Dihydrochloride, 2,2'-azobis (N, N'-dimethyleneisobutylamidine), 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate Azo initiators such as potassium persulfate and persulfate initiators such as ammonium persulfate, such as peroxide initiators such as benzoyl peroxide, t-butyl hydroperoxide and hydrogen peroxide, such as substituted ethane initiators such as phenyl substituted ether For example, carbonyl initiators, such as an aromatic carbonyl compound, For example, a persulfate salt, And the like redox initiators of a combination of sodium hydrogen sulfate, and a combination of peroxide and sodium ascorbate.

These polymerization initiators are used alone or in combination as appropriate. In addition, the compounding ratio of these polymerization initiators is about 0.005-1 weight part with respect to 100 weight part of monomer mixtures, for example.

In addition, water may be mix | blended only at the time of emulsion preparation, or may be mix | blended further after that, and it can select suitably according to the polymerization method mentioned later.

In addition, the blending ratio of water is not particularly limited, but is adjusted so that the solid content concentration of the acrylic polymer after emulsion polymerization is, for example, 30 to 75% by weight, preferably 35 to 70% by weight.

Moreover, additives, such as a chain transfer agent and a crosslinking agent, can be suitably mix | blended with such an emulsion as needed.

Although it does not restrict | limit especially as a chain transfer agent, For example, mercaptans, such as 1-dodecane thiol, mercaptoacetic acid, 2-mercaptoethanol, 2-ethylhexyl thioglycolic acid, 2, 3- dimercapto-1-propanol, etc. Can be mentioned.

These chain transfer agents are suitably used alone or in combination. In addition, the compounding ratio of a chain transfer agent is about 0.001-0.5 weight part with respect to 100 weight part of monomer mixtures, for example.

The crosslinking agent is not particularly limited, and examples thereof include an isocyanate crosslinking agent, an epoxy crosslinking agent, an oxazoline crosslinking agent, an aziridine crosslinking agent and a metal chelate crosslinking agent. Moreover, the said silane type monomer can also be used as a crosslinking agent.

These crosslinking agents are suitably used alone or in combination. In addition, the compounding ratio of a crosslinking agent is about 0.01-5 weight part with respect to 100 weight part of monomer mixtures, for example.

Moreover, as another additive, well-known thing normally used as an additive of emulsion polymerization, such as a pH buffer, a neutralizing agent, antifoaming agent, stabilizer, etc. is mentioned, for example.

The emulsion polymerization method is not particularly limited and can be appropriately selected from a batch polymerization method, a total dropping method and a two-stage polymerization method in which these are combined.

For example, in the batch polymerization method, a monomer mixture, a reactive emulsifier and water are added to a reaction vessel, emulsified by stirring and mixing to prepare an emulsion, and then, a polymerization initiator and water are added to the reaction vessel, if necessary, to emulsion polymerization. do.

In addition, in the total dropping method, for example, a monomer mixture, a reactive emulsifier and water are first added and emulsified by stirring and mixing to prepare a dropping solution, a polymerization initiator and water are added to the reaction vessel, and then the dropping solution is reacted. It is dripped in a container and emulsion-polymerizes.

By such emulsion polymerization, the monomer mixture is polymerized, and an acrylic polymer is synthesized, and an acrylic polymer emulsion in which the acrylic polymer is emulsified in water can be obtained.

And the adhesive composition for optical members of this invention is prepared by mix | blending a silane coupling agent with the acryl-type polymer emulsion obtained in this way.

Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like. Epoxy group-containing silane coupling agents such as 3-aminopropyltrimethoxysilane, N-2 (aminoethyl) 3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N- (1,3 Amino-group containing silane coupling agents, such as-dimethyl- butylidene) propylamine, For example, (meth) acryl group, such as 3-acryloxypropyl trimethoxysilane and 3-methacryloxypropyl triethoxysilane Isocyanate group containing silane coupling agents, such as a silane coupling agent, such as 3-isocyanate propyl triethoxysilane, etc. are mentioned.

By using such a silane coupling agent, durability can be improved.

These silane coupling agents are used suitably alone or in combination. The blending ratio of the silane coupling agent is 0.01 to 1 part by weight, preferably 0.03 to 0.5 part by weight based on 100 parts by weight of the monomer mixture, that is, 100 parts by weight of the solid content of the acrylic polymer emulsion. If it is less than 0.01 weight part, durability improvement cannot be aimed at and if it exceeds 1 weight part, removability will not be improved.

Moreover, well-known additives, such as a ultraviolet absorber, an anti-aging agent, a softener, dye, a pigment, and a filler, can also be mix | blended with the adhesive composition for optical members of this invention as needed.

And the adhesive composition for optical members obtained in this way is excellent in durability, such as heat resistance and moisture resistance, and also expresses the outstanding re-peelability which can peel easily even after long time elapsed or storing in high temperature, high humidity atmosphere. Therefore, it can use suitably as an adhesion layer for optical members for sticking the optical component used for a liquid crystal display device.

That is, the adhesive layer for optical members of this invention can be formed as an adhesive sheet for optical members, for example by coating the adhesive composition for optical members of this invention on the base material with which the surface was peeled, and drying it, and this is an optical component The optical member of this invention can be manufactured by transferring to.

The substrate is not particularly limited, and for example, plastic films such as polypropylene film, ethylene-propylene copolymer film, polyester film, polyvinyl chloride, paper such as kraft paper, for example cloth such as cotton cloth, staple fiber cloth, such as poly Nonwoven fabrics, such as ester nonwoven fabric and vinylon nonwoven fabric, such as metal foil, etc. are mentioned.

In addition, although the thickness of a base material is suitably selected according to the objective, a use, etc., it is about 20-100 micrometers, for example.

In addition, although the peeling process of the surface of a base material is not restrict | limited, For example, a silicone peeling process, a long chain alkyl peeling process, a fluorine peeling process, etc. are used.

And in order to coat the adhesive composition for optical members of this invention on a base material, For example, a gravure roll coater, a reverse roll coater, a kiss roll coater, a dip roll coater, a bar coater, a knife coater, a spray coater, a curtain coater, a die coater, etc. The coater normally used for lamination | stacking of the adhesive layer of is used.

In addition, in such coating, the adhesive composition for optical members is coated so that the thickness after drying may be 2-500 micrometers, for example, Preferably it is 5-100 micrometers.

In addition, the subsequent drying is heated to, for example, about 50 to 200 ° C, preferably about 80 to 160 ° C by a known method.

The adhesive layer for optical members obtained in this way is 30 to 95 weight% of the gel powder (solvent insoluble content), Preferably it is 35 to 90 weight%. If it is less than 30 weight%, the adhesive force to glass may become high too much, and foaming may arise under high temperature, high humidity, and when it exceeds 95 weight%, lifting and peeling may arise under high temperature, high humidity.

Thereby, as shown in FIG. 1, the adhesive sheet 3 for optical members in which the adhesive layer 2 for optical members was laminated | stacked on the base material 1 can be obtained.

And an optical member can be obtained by transferring the adhesive layer for optical members to an optical component from the base material of this adhesive sheet for optical members.

Although an optical component is not specifically limited, For example, it is used for a liquid crystal display device, etc., For example, optical films, such as a polarizing film (polarizing plate), a retardation film (phase difference plate), an elliptically polarizing film (elliptical polarizing plate), are mentioned.

It does not specifically limit as a polarizer which comprises a polarizing film, Various things can be used. Examples of the polarizer include a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, and an ethylene-vinyl acetate copolymer-based partially saponified film such that a dichroic substance such as iodine or a dichroic dye is adsorbed and stretched. Stretched film and the film which laminated | stacked protective films, such as a triacetyl cellulose film and a polycarbonate film, on this stretched film, Furthermore, fine unevenness | corrugation was performed to the stretched film and the protective film, the vapor deposition process, and the protective adhesive film laminated | stacked And various surface-treated ones. Moreover, polyene type orientation films, such as the dehydration process of polyvinyl alcohol and the dehydrochloric acid process of polyvinyl chloride, etc. are mentioned, for example. The thickness of the polarizer is not particularly limited and is generally about 5 to 80 µm.

In addition, on one or both surfaces of the polarizer, a transparent protective layer can be provided as a coating layer made of a polymer or as a laminated layer of a film for the purpose of water resistance and the like. As a transparent polymer or film material which forms a transparent protective layer, although it is obtained using a transparent material suitably, what is excellent in transparency, mechanical strength, thermal stability, water barrier property, etc. is used preferably. The thickness of a transparent protective layer is not specifically limited, About 10-300 micrometers is common.

As a material for forming such a transparent protective layer, for example, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, for example cellulose polymers such as cellulose acetate, cellulose triacetate, for example acrylic polymers such as polymethyl methacrylate, For example, styrene polymers, such as polystyrene and an acrylonitrile styrene copolymer (AS resin), for example, a polycarbonate polymer, etc. are mentioned. Further, for example, polyolefin polymers such as polyethylene, polypropylene, cycloolefin and norbornene structures, polyolefin polymers such as ethylene and propylene copolymers, vinyl chloride polymers, amide polymers such as nylon and aromatic polyamides, imide polymers and sulfides Phone polymer, polyether sulfone polymer, polyether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, allylate polymer, polyoxymethylene polymer, Epoxy type polymers or the blended polymers of the above-mentioned polymers are also mentioned.

As a retardation film, the birefringent film, liquid crystal polymer film, etc. which carried out the uniaxial stretching process or the biaxial stretching process of a polymeric raw material are mentioned. The thickness of the retardation film is not particularly limited, and is generally about 20 to 150 µm. A retardation film can also be formed as two or more layers of stretched film superimpositions, etc., and having controlled the optical characteristics, such as retardation.

Examples of the polymer material include polyvinyl alcohol, polyvinyl butyral, polymethyl vinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polycarbonate, polymethyl methacrylate, and polyolefin. , Polyallylate, polysulfone, polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, polyphenylene sulfide, polyphenylene oxide, polyallyl sulfone, polyvinyl alcohol, polyamide, polyimide, polyolefin, polyvinyl chloride , Cellulose polymers, or binary, ternary copolymers, graft copolymers, blended polymers, and the like thereof. These high molecular materials become an orientation substance (stretched film) by extending | stretching etc.

As a liquid crystalline polymer, various things, such as main chain type and side chain which the conjugated linear atomic group (mesogen) which provides liquid crystal aligning property, were introduce | transduced into the main chain and side chain of a polymer, are mentioned, for example.

As a specific example of a main chain type liquid crystalline polymer, the nematic oriented polyester-type liquid crystalline polymer etc. which are structures which couple | bonded mesogenic groups in the spacer part which provides flexibility are mentioned.

Specific examples of the branched liquid crystalline polymer include polysiloxane, polyacrylate, polymethacrylate, or polymalonate as a main chain skeleton, and a para-substituted cyclic compound unit having a nematic orientation imparting property through a spacer portion composed of a conjugated atomic group as a side chain. The thing which has the mesogenic part which consists of these etc. is mentioned. These liquid crystalline polymers may be formed by rubbing the surface of a thin film such as polyimide or polyvinyl alcohol formed on a glass plate, or by depositing silicon oxide on all sides. It can be obtained by developing and heat-processing a solution.

An elliptically polarizing film is used for retardation compensation of a liquid crystal cell etc. for the purpose of prevention of coloring, expansion of a visual range, etc., and can be obtained by laminating | stacking a polarizing film and retardation film, for example.

Moreover, a polarizing film and retardation film can also be laminated | stacked and used, and can be used as a reflection type polarizing film, a semi-transmissive layer type polarizing film, a polarization separation polarizing film, etc.

Moreover, said optical film can also be used as an optical compensation film, other various viewing angle expansion films, and can also be used as a brightness improving film. Moreover, a polarizing film can also be used as an anti-glare sheet by providing the reflective layer of a fine uneven structure on the surface.

In order to transfer the adhesive layer for an optical member to an optical component, for example, the adhesive layer for an optical member of the adhesive sheet for an optical member is pressed in contact with an optical component, and only a base material is peeled from an optical component after that.

As a result, for example, as shown in FIG. 2, the optical member 5 in which the adhesive layer 2 for an optical member is laminated on one surface (or both surfaces as shown by virtual lines) of the optical component 4 can be obtained. .

In addition to the above-described method, the adhesive composition for an optical member of the present invention is directly coated onto an optical component by the same method as described above, followed by drying to form an adhesive layer for the optical member directly on the optical component, and at the same time, the optical member The optical member in which the adhesive layer for laminated | stacked on the optical component can also be produced.

Moreover, in the adhesive sheet for optical members and optical member mentioned above, the protective film which peeled off, such as a peeling liner, was apply | coated appropriately to the surface of the adhesive layer 2 for optical members exposed until it is provided for actual use. You can also do it. In addition, in FIG. 1 and FIG. 2, the peeling liner is shown with the virtual line (symbol 6).

And in the adhesive layer for optical members and the adhesive sheet for optical members of this invention obtained in this way, even if it is a physical property necessary for adhesion | attachment of an optical component, ie, it can prevent a peeling or peeling under high temperature, high humidity environment, and it is excellent in heat resistance, moisture resistance, etc. It is excellent in durability and can be easily peeled after that even after storing for a long time after evaporation of an optical component or in high temperature, high humidity atmosphere.

Especially the adhesive sheet for optical members of this invention adheres to glass, and the adhesive force with respect to glass after 17 hours passes at 60 degreeC becomes 10 N / 25 mm or less, and can exhibit favorable removability. Therefore, the optical component can be easily peeled off without damaging the liquid crystal display device at the time of peeling the optical component to the liquid crystal display device.

Example

Hereinafter, an Example and a comparative example are given 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, the gel powder of the adhesive sheet for optical members obtained by each Example and each comparative example was computed using the following formula (1).

Gel powder measuring method

Adhesive layer W ₁ [g] 7 ilgan immersed in 23 ℃ of ethyl acetate and the and the weight after its drying W ₂ [g] one time, the gel content _{(wt%) = (W 2 / W} 1) × 100 ( formula ( One)).

Example 1

70 parts by weight of 2-ethylhexyl acrylate, 30 parts by weight of butyl acrylate, 1 part by weight of acrylic acid, and 0.07 part by weight of 3-acryloxypropyltriethoxysilane, acryon HS-10 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd. ) 2 parts by weight) was added to 25 parts by weight of water and emulsified with a homomixer to prepare an emulsion.

Next, the 4-necked flask equipped with the nitrogen introduction tube, the cooling tube, and the thermometer was nitrogen-substituted for 1 hour, and then the 4-necked flask was 30 parts by weight of water and 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate (VA-057, manufactured by Hwagwang Pure Chemical Co., Ltd.), 0.1 part by weight was added, and the emulsion obtained above was added dropwise at 59 ° C. over 4.5 hours to perform emulsion polymerization. After the completion of the polymerization, the pH was adjusted to 8 by adding ammonia to obtain an acrylic polymer emulsion A1.

Next, 0.2 weight part of 3-glycidoxy propyl triethoxysilane (KBE-403, Shin-Etsu Chemical Co., Ltd. product) is added with respect to 100 weight part of solid content of acrylic polymer emulsion A1, and the adhesive composition for optical members is obtained. It was.

The adhesive composition for optical members is coated on a 38 micrometers PET (polyethylene terephthalate) film which carried out the silicone peeling process so that the thickness after drying may be set to 20 micrometers, and it dries at 120 degreeC for 5 minutes, and consists of the optical composition which consists of adhesive compositions for optical members The adhesive sheet for optical members in which the adhesive layer for members was laminated | stacked was obtained. In addition, the gel powder was 72 weight%.

Then, the adhesive layer for optical members of this adhesive sheet for optical members was transferred to the polarizing film, and the optical member was produced.

Example 2

By the same operation as in Example 1, except that Akaro HS-10 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) was changed to Akaroon HS-20 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) An acrylic polymer emulsion A2 was obtained.

Next, 0.2 weight part of 3-glycidoxy propyl triethoxysilane (KBE-403, Shin-Etsu Chemical Co., Ltd. product) is added with respect to 100 weight part of solid content of acrylic polymer emulsion A2, and the adhesive composition for optical members is obtained. It was.

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1.

In addition, the gel powder of the adhesive sheet for optical members was 71 weight%.

Example 3

To 70 parts by weight of 2-ethylhexyl acrylate, 30 parts by weight of butyl acrylate and 1 part by weight of acrylic acid, to 120 parts by weight of water added 2 parts by weight of acroon HS-10 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) The emulsion was prepared by adding and emulsifying with a homomixer.

Next, the four-necked flask equipped with the nitrogen introduction tube, the cooling tube, and the thermometer was nitrogen-substituted for 1 hour, and then the emulsion and the 2,2'-azobis [N- (2-carboxyethyl) obtained above were added to the four-necked flask. ) -2-methylpropionamidine] hydrate (VA-057, manufactured by Hwagwang Pure Chemical Co., Ltd.) 0.03 parts by weight was added, and emulsion polymerization was performed at 56 ° C. for 3.5 hours (batch part).

Subsequently, 70 parts by weight of 2-ethylhexyl acrylate, 30 parts by weight of butyl acrylate, 1 part by weight of acrylic acid, 2 parts by weight of acroon HS-10 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) and water 30 parts by weight An emulsion containing part was prepared, this was dripped at 59 degreeC over 2.5 hours, and the emulsion polymerization was carried out (dropping part). After completion of the polymerization, the pH was adjusted to 8 by adding ammonia to obtain an acrylic polymer emulsion A3. In addition, the ratio of a batch part and a dripping part was 70/30.

Next, 0.2 weight part of 3-glycidoxy propyl triethoxysilane (KBE-403, Shin-Etsu Chemical Co., Ltd. product) is added with respect to 100 weight part of solid content of acrylic polymer emulsion A3, and the adhesive composition for optical members is obtained. It was.

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1.

In addition, the gel powder of the adhesive sheet for optical members was 82 weight%.

Comparative Example 1

Except for changing Acro Aaron HS-10 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) to hytenol NF8 (non-reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) Polymer emulsion A4 was obtained.

Next, 0.2 weight part of 3-glycidoxy propyl triethoxysilane (KBE-403, Shin-Etsu Chemical Co., Ltd. product) is added with respect to 100 weight part of solid content of acrylic polymer emulsion A4, and the adhesive composition for optical members is obtained. It was.

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1. In addition, the gel powder of the adhesive sheet for optical members was 58 weight%.

Comparative Example 2

The acrylic polymer was operated in the same manner as in Example 1, except that Akaro HS-10 (reactive emulsifier, manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.) was changed to Laterum E-118B (non-reactive emulsifier, Gao Co., Ltd.). Emulsion A5 was obtained.

Next, 0.2 weight part of 3-glycidoxy propyl triethoxysilane (KBE-403, Shin-Etsu Chemical Co., Ltd. product) was added with respect to 100 weight part of acrylic polymer emulsion A5 solid content, and the adhesive composition for optical members was obtained. .

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1.

In addition, the gel powder of the adhesive sheet for optical members was 71 weight%.

Comparative Example 3

Except for changing Acro Aaron HS-10 (reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) to hytenol NF8 (non-reactive emulsifier, Daiichi Kogyo Pharmaceutical Co., Ltd.) Polymer emulsion A6 was obtained.

Next, 0.2 weight part of 3-glycidoxy propyl triethoxysilane (KBE-403, Shin-Etsu Chemical Co., Ltd. product) was added with respect to 100 weight part of acrylic polymer emulsion A6 solid content, and the adhesive composition for optical members was obtained. .

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1.

In addition, the gel powder of the adhesive sheet for optical members was 80 weight%.

Comparative Example 4

By the same operation as in Example 1, except that 3-glycidoxypropyltriethoxysilane (KBE-403, manufactured by Shin-Etsu Chemical Co., Ltd.) was not added to the acrylic polymer emulsion A1 obtained in Example 1. The adhesive composition for optical members was obtained.

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1.

In addition, the gel powder of the adhesive sheet for optical members was 72 weight%.

Comparative Example 5

3 parts by weight of 3-glycidoxypropyltriethoxysilane (KBE-403, manufactured by Shin-Etsu Chemical Co., Ltd.) was added to 100 parts by weight of the solid content of the acrylic polymer emulsion A1 obtained in Example 1 A composition was obtained.

Hereinafter, the adhesive sheet for optical members and the optical member were produced by operation similar to Example 1.

In addition, the gel powder of the adhesive sheet for optical members was 72 weight%.

Comparative Example 6

70 parts by weight of 2-ethylhexyl acrylate, 30 parts by weight of butyl acrylate, 1 part by weight of acrylic acid, 0.15 part by weight of 2-hydroxyethyl acrylate, 0.1 part by weight of 2,2-azobisisobutyronitrile and ethyl acetate 200 parts by weight was put in a four-necked flask equipped with a nitrogen inlet tube and a cooling tube, and after sufficient nitrogen substitution, emulsion polymerization was carried out at 55 ° C. for 6 hours while stirring under a nitrogen stream to obtain an acrylic polymer solution A8.

Next, 0.2 part by weight of 3-glycidoxypropyltriethoxysilane (KBE-403, manufactured by Shin-Etsu Chemical Co., Ltd.) and trimethylolpropane based on 100 parts by weight of the solid content of the acrylic polymer-solution A8 1.5 weight part of polyisocyanate type crosslinking agents which consist of a tolylene diisocyanate addition product were mixed uniformly, and the adhesive composition for optical members was obtained.

The pressure-sensitive adhesive composition for optical members was coated on a 38 μm PET (polyethylene terephthalate) film subjected to silicone peeling so that the thickness after drying was 20 μm, followed by drying and crosslinking at 120 ° C. for 5 minutes to obtain an adhesive composition for optical members. The adhesive sheet for optical members which laminated | stacked the adhesive layer for optical members which consists of was obtained.

In addition, the gel powder of the adhesive sheet for optical members was 69 weight%.

Then, the optical member was produced by transferring the adhesive layer for optical members of this adhesive sheet for optical members to a polarizing film, and aging-processing at 50 degreeC for 24 hours.

evaluation

1) adhesion

The optical member (25 mm in width) obtained by each Example and each comparative example was adhere | attached by reciprocating a roll of 2 kg once to an alkali free glass plate, and it processed at 50 degreeC and 0.5 MPa autoclave for 30 minutes, and then peeled off 90 degrees Peeling adhesive force (initial adhesive force) (N / 25mm) was measured at ° and a peeling rate of 300 mm / min. The results are shown in Table 1.

Moreover, after leaving for 17 hours at 60 degreeC after autoclave process, peeling adhesive force (post-durability adhesive force) (N / 25mm) was measured at the peeling angle of 90 degrees, and peeling rate 300mm / min. The results are shown in Table 1. In addition, it is desired that the endurance adhesive force does not increase at the same time as the initial adhesive force.

2) heat resistance

The optical members (12-inch size) obtained in each Example and each Comparative Example were adhered to an alkali-free glass having a thickness of 0.5 mm, treated for 30 minutes in an autoclave of 50 ° C and 0.5 MPa, and then 300 under an atmosphere of 90 ° C. It was left to stand for time and the lifting and peeling from the glass of the optical member were visually observed. The results are shown in Table 1.

In addition, the determination criteria of heat resistance are as follows.

○: no lifting and peeling

X: There exists peeling in less than 50% of range with respect to adhesion area

××: there is peeling in the range of 50% or more with respect to the adhesion area

3) moisture resistance

The optical member (12 inch size) obtained in each example and each comparative example was adhered to an alkali free glass having a thickness of 0.5 mm, treated for 30 minutes in an autoclave of 50 ° C and 0.5 MPa, and then 60 ° C and 90% RH. It was left to stand in the atmosphere for 300 hours, and the lifting and peeling from the glass of the optical member were visually observed. The results are shown in Table 1.

In addition, the determination criteria of moisture resistance are as follows.

○: no lifting and peeling

X: There exists peeling in less than 50% of range with respect to adhesion area

××: there is peeling in the range of 50% or more with respect to the adhesion area

From Table 1, although each Example showed the favorable result in all of re-peelability, heat resistance, and moisture resistance, it turns out that each comparative example has a poor result in any one or more items.

In addition, although the above description was provided as an exemplary embodiment of the present invention, this is only a mere illustration and should not be interpreted limitedly. Modifications of the invention which are apparent to those skilled in the art are included in the following claims.

The pressure-sensitive adhesive layer for an optical member of the present invention and the pressure-sensitive adhesive sheet for an optical member of the present invention comprising the pressure-sensitive adhesive composition for an optical member of the present invention can prevent lifting or peeling even under a high temperature and high humidity environment, and after adhesion of the optical component, Even after storing for a long time or storing in a high temperature, high humidity atmosphere, it can peel easily after that. Therefore, the optical component with which the adhesion layer for optical members of this invention is provided can be used suitably as an optical member used for a liquid crystal display device, for example.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one embodiment of the adhesive layer for optical members of this invention, and the adhesive sheet for optical members of this invention.

It is sectional drawing which shows typically one embodiment of the optical member of this invention.

Explanation of symbols for the main parts of the drawings

2: adhesive layer for optical members 3: adhesive sheet for optical members

4: optical member 5: optical member

Claims (6)

Acrylic polymer emulsion obtained by emulsion-polymerizing the monomer mixture containing 80 weight% or more of (meth) acrylic acid ester, the emulsion containing the reactive emulsifier containing a radically polymerizable functional group, and the polymerization initiator, and 0.01 to 1 part by weight of the silane coupling agent based on 100 parts by weight of the solid content of the acrylic polymer emulsion A pressure-sensitive adhesive composition for an optical member comprising a. Acrylic polymer emulsion obtained by emulsion-polymerizing the monomer mixture containing 80 weight% or more of (meth) acrylic acid ester, the emulsion containing the reactive emulsifier containing a radically polymerizable functional group, and a polymerization initiator, and the solid content of the said acrylic polymer emulsion 100weight weight The adhesive layer for optical members which consists of an adhesive composition for optical members containing 0.01-1 weight part of silane coupling agents with respect to a part. Acrylic polymer emulsion obtained by emulsion-polymerizing the monomer mixture containing 80 weight% or more of (meth) acrylic acid ester, the emulsion containing the reactive emulsifier containing a radically polymerizable functional group, and a polymerization initiator, and the solid content of the said acrylic polymer emulsion 100weight weight The adhesive sheet for optical members which consists of an adhesive composition for optical members containing 0.01-1 weight part of silane coupling agents with respect to a part is provided. The method of claim 3, wherein Adhesion to glass, The adhesive force with respect to the said glass after 17 hours at 60 degreeC is 10 N / 25 mm or less, The adhesive sheet for optical members characterized by the above-mentioned. Acrylic polymer emulsion obtained by emulsion-polymerizing the monomer mixture containing 80 weight% or more of (meth) acrylic acid ester, the emulsion containing the reactive emulsifier containing a radically polymerizable functional group, and a polymerization initiator, and the solid content of the said acrylic polymer emulsion 100weight weight The optical member adhesive layer which consists of an adhesive composition for optical members containing 0.01-1 weight part of silane coupling agents with respect to a part is provided in the one or both surfaces of an optical component. The method of claim 5, The optical member is any one of a polarizing plate, a retardation plate and an elliptical polarizing plate.