CN105319638A - Method for manufacturing polarizing plate - Google Patents

Abstract

The invention provides a method for manufacturing a polarizing plate on which a polarizing film and a protecting film are well bonded. According to the method, the polarizing film comprises a polyvinylalcohol resin film with iodine and dichroic dye absorbed and oriented thereon, a protecting film formed by thermoplastic resin is attached on at least one surface of the polarizing film by the use of an ultraviolet curing adhesive agent, and therefore the polarizing plate is obtained. The method is characterized by comprising following steps: (a) enabling the protecting film to be in contact with water; (b) forming an adhesive agent layer provided with the ultraviolet curing adhesive agent on at least one of the protecting film subjected to the step (a) and the polarizing film; (c) laminating the protecting film and the polarizing film through the adhesive agent layer so as to obtain the laminated film; and (d) curing the adhesive agent layer through ultraviolet radiation on the laminated film.

Description

The manufacture method of polarization plates

Technical field

The present invention relates to the manufacture method of polarization plates.

Background technology

Polarizing coating is used in the image display devices such as liquid crystal indicator, organic EL display, plasma display device (PDP).

As polarizing coating, being widely used in gas absorption quantity in polyvinyl alcohol resin film has the polarizing coating of iodine or dichroic dye, and usual and diaphragm is fitted and makes polarization plates.Such as, disclose in Japanese Unexamined Patent Publication 2008-287207 publication (patent documentation 1) and transparent protective film is directly fitted in polarizing coating by active energy ray curable bonding agent, this bonding agent is solidified thus manufactures the method for polarization plates.But their bonding strength is not necessarily abundant, is sometimes peeling.

Prior art document

Patent documentation

Patent documentation 1: Japanese Unexamined Patent Publication 2008-287207 publication, especially paragraph 0098 etc.

Summary of the invention

The problem that invention will solve

The present invention completes to solve above-mentioned problem, is the manufacture method providing polarizing coating and the polarization plates excellent in adhesion with the diaphragm formed by thermoplastic resin.

For the means of dealing with problems

Namely the invention provides a kind of manufacture method of polarization plates; it utilizes ultraviolet hardening bonding agent; in polyvinyl alcohol resin film, gas absorption quantity has the diaphragm that formed by thermoplastic resin and manufacture the method for polarization plates of at least simultaneously fitting of the polarizing coating of iodine or dichroic dye; it is characterized in that

Possess: make the operation (a) that said protection film contacts with water;

At least one film in the diaphragm be selected from after above-mentioned operation (a) and polarizing coating is formed the operation (b) comprising the bond layer of ultraviolet hardening bonding agent;

Make diaphragm and polarizing coating across the stacked operation (c) obtaining stacked film of above-mentioned bond layer; And

To the operation (d) that above-mentioned stacked film irradiation ultraviolet radiation makes bond layer solidify.

In above-mentioned manufacture method, before the operation (a) making diaphragm contact with water, comprise the operation (a-1) that diaphragm is heated.

In addition, above-mentioned ultraviolet hardening bonding agent can be heated before formation bond layer.In addition, this ultraviolet hardening bonding agent is preferably the epoxy bonding agent of cationic polymerization type, and more preferably this epoxy bonding agent is included in the epoxy resin not containing aromatic ring in molecule.This epoxy bonding agent can comprise epoxy resin and Cationic photoinitiator.

In the present invention, the thermoplastic resin forming diaphragm is preferably acrylic resin.In addition, the water percentage of the diaphragm in the present invention after the operation making diaphragm contact with water is preferably 0.2 ~ 5 % by weight.

Invention effect

According to the present invention, contacted with water by the diaphragm that makes to comprise thermoplastic resin, the diaphragm that especially comprises acrylic resin, the polarization plates excellent in adhesion of polarizing coating and diaphragm can be provided.The polarization plates obtained by the present invention can compatibly for liquid crystal indicator.

Embodiment

The present invention relates to and use ultraviolet hardening bonding agent that the diaphragm comprising thermoplastic resin is fitted in polarizing coating to manufacture the method for polarization plates, it is characterized in that possessing: make the operation that diaphragm contacts with water; Be selected from the one side coated UV line curing type bonding agent of at least one film in diaphragm and polarizing coating to form the operation of bond layer; Make diaphragm and polarizing coating across the stacked operation obtaining stacked film of bond layer; And to the operation that stacked film irradiation ultraviolet radiation makes bond layer solidify.

[polarization plates]

The polarization plates obtained by manufacture method of the present invention has the formation utilizing ultraviolet hardening bonding agent the diaphragm comprising thermoplastic resin to be fitted in the polarizing coating comprising polyvinyl alcohol resin.

(polarizing coating)

The polarizing coating used in the present invention comprises polyvinyl alcohol resin film, and specifically polyvinyl alcohol resin film gas absorption quantity has the film after dichromatism pigment.The polyvinyl alcohol resin forming polyvinyl alcohol resin film is used as after polyvinyl acetate system resin can being carried out saponification.As polyvinyl acetate system resin, except as except the polyvinyl acetate of leifa, can also enumerate vinyl acetate with can with the multipolymer etc. of other monomer of its copolymerization.As can with the example of other monomer of vinyl acetate copolymerization, unsaturated carboxylic acid, alkene, vinyl ether, unsaturated sulfonic acid can be enumerated, there is the acrylamide etc. of ammonium.

The saponification degree of polyvinyl alcohol resin is generally more than 85 % by mole, is preferably more than 98 % by mole.In addition, polyvinyl alcohol resin can be modified, and such as, also can use polyvinyl formal, polyvinyl acetal and the polyvinyl butyral etc. that obtain with aldehydes modification.The degree of polymerization of polyvinyl alcohol resin is generally about 1000 ~ 10000, is preferably about 1500 ~ 5000.

The film that such polyvinyl alcohol resin is made be can be used as the reel film (former anti-Off イ Le system) of polarizing coating.Polyvinyl alcohol resin can adopt known proper method masking.The thickness comprising the reel film of polyvinyl alcohol resin is such as about 10 ~ 150 μm.

Polarizing coating passes through following operation manufacture usually: the reel film dyeing comprising polyvinyl alcohol resin film by as described above with dichromatism pigment and this dichromatism pigment is adsorbed operation (dyeing treatment process), will the operation (boric acid treatment process) of the polyvinyl alcohol resin film boric acid aqueous solution process of dichromatism pigment and the operation (washing treatment process) at this boric acid aqueous solution process after washing be adsorbed with.

In addition, when manufacturing polarizing coating, usual uniaxial tension polyvinyl alcohol resin film, but this uniaxial tension both can carry out before dyeing treatment process, also can carry out in dyeing treatment process, can also carry out after dyeing treatment process.When carrying out uniaxial tension after the treatment process that dyes, uniaxial tension both can carry out before boric acid treatment process, also can carry out in boric acid treatment process.Certainly, also uniaxial tension can be carried out in these multiple stages.Uniaxial tension both can stretch between the roller that peripheral speed is different, and hot-rolling also can be used to stretch.In addition, both can be the dry type stretching carrying out in an atmosphere stretching, also can be that the wet type of carrying out under swelling in a solvent state stretching stretches.Stretching ratio is generally about 3 ~ 8 times.

In dyeing treatment process, dichromatism pigment is utilized to dye to polyvinyl alcohol resin film, such as, by making polyvinyl alcohol resin film immersion carry out in the aqueous solution containing dichromatism pigment.As dichromatism pigment, such as, iodine, dichroic dye etc. can be used.Dichroic dye such as comprises by the C.I. directly dichromatism direct dyes that formed of the bis-azo compound such as red 39 (C.I.DIRECTRED39); The dichromatism direct dyes formed by trisazo compound, four azo-compounds etc.Moreover polyvinyl alcohol resin film preferably implements the dip treating in water before dyeing process.

When using iodine as dichromatism pigment, be typically employed in and flood polyvinyl alcohol resin film in the aqueous solution containing iodine and potassium iodide and the method that dyes.In this aqueous solution, the content of iodine is 0.01 ~ 1 weight portion usually in the water of every 100 weight portions, and the content of potassium iodide is 0.5 ~ 20 weight portion usually in the water of every 100 weight portions.When using iodine as dichromatism pigment, the aqueous temperature for dyeing is generally 20 ~ 40 DEG C, and in addition, the dip time (dyeing time) in this aqueous solution is generally 20 ~ 1800 seconds.

On the other hand, when using dichroic dye as dichromatism pigment, be typically employed in and flood polyvinyl alcohol resin film in the aqueous solution containing water-soluble dichroic dye and the method that dyes.In this aqueous solution, the content of dichroic dye is 1 × 10 usually in the water of every 100 weight portions ^-4~ 10 weight portions, are preferably 1 × 10 ^-3~ 1 weight portion, is more preferably 1 × 10 ^-3~ 1 × 10 ^-2weight portion.This aqueous solution also can containing inorganic salts such as the sodium sulphate as dyeing assistant.When using dichroic dye as dichromatism pigment, the temperature for the aqueous dye solutions dyeed is generally 20 ~ 80 DEG C, and in addition, the dip time (dyeing time) in this aqueous solution is generally 10 ~ 1800 seconds.

Boric acid treatment process is by carrying out the polyvinyl alcohol resin film immersion after dichromatism pigment dyeing in boric acid aqueous solution.The amount of boric acid aqueous solution mesoboric acid is 2 ~ 15 weight portions usually in the water of every 100 weight portions, is preferably 5 ~ 12 weight portions.When using iodine as dichromatism pigment in above-mentioned dyeing treatment process, the boric acid aqueous solution for this boric acid treatment process preferably contains potassium iodide.In this case, in boric acid aqueous solution, the amount of potassium iodide is 0.1 ~ 15 weight portion usually in the water of every 100 weight portions, is preferably 5 ~ 12 weight portions.Dip time in boric acid aqueous solution is generally 60 ~ 1200 seconds, is preferably 150 ~ 600 seconds, more preferably 200 ~ 400 seconds.The temperature of boric acid aqueous solution is generally more than 50 DEG C, is preferably 50 ~ 85 DEG C, is more preferably 60 ~ 80 DEG C.

In ensuing washing treatment process, remove the medicaments such as unnecessary boric acid, iodine, such as, by making film immersion carry out in water from the polyvinyl alcohol resin film after boric acid process.The temperature of the water in washing process is generally 5 ~ 40 DEG C, and dip time is generally 1 ~ 120 second.After washing process, dry process is implemented to film and obtains polarizing coating.Dry process can use such as air drier, far infra-red heater etc.The temperature of dry process is generally 30 ~ 100 DEG C, is preferably 50 ~ 80 DEG C, is generally 60 ~ 600 seconds drying time, is preferably 120 ~ 600 seconds.

The thickness of the polarizing coating obtained is preferably in the scope of 5 ~ 40 μm usually, is more preferably 5 ~ 30 μm.

(diaphragm)

The diaphragm used in the present invention is for physical property or the film chemically protecting polarizing coating, is the film comprising thermoplastic resin.As this thermoplastic resin, such as, can enumerate the ethylene series resins such as tygon, polypropylene and Polyvinylchloride; The polyester based resin such as polyethylene terephthalate and PEN; Polycarbonate-based resin; The cyclic olefine resins such as norbornene resin; Polyurethane series resin; The acrylic resin such as polyacrylate and polymethylmethacrylate; The transparent polymer materials such as cellulose-based resin such as diacetyl cellulose and triacetyl cellulose (TAC).Wherein, polyolefin-based resins, polyester based resin, polycarbonate-based resin, cyclic olefine resin, acrylic resin and cellulose-based resin are owing to effectively improving the cementability of polarizing coating and diaphragm but suitable in the polarization plates that obtains in the present invention, acrylic resin is particularly suitable.It should be noted that, in thermoplastic resin, the adjuvants such as ultraviolet light absorber, antioxidant, plastifier can be contained as required.Thermoplastic resin can be filmed by known methods such as casting painting or extrusion moldings and form diaphragm.

Above-mentioned cyclic olefine resin refers to the thermoplastic resin of the unit with following monomer: the monomer comprising the cycloolefin such as norborene, many rings norborneol alkene monomer.Cyclic olefine resin both can be the hydride using the hydride of the ring-opening polymerization polymer of single cycloolefin, use the ring opening copolymer thing of two or more cycloolefin, also can be the addition copolymer of cycloolefin and chain olefin and/or the aromatics with vinyl etc.In addition, the cyclic olefine resin having imported polar group in main chain or side chain is also effective.

As commercially available thermoplastic cyclic olefin system resin, have " Topas " that sold by Polyplastics Co., Ltd. of TopasAdvancedPolymersGmbH Inc., the “ ア ー ト Application sold by JSR Corp. " (ARTON) (registered trademark), " ゼ オ ノ ア (ZEONOR) (registered trademark) " and " ゼ オ ネ ッ Network ス (ZEONEX) (registered trademark) " of being sold by Zeon Corp, " APEL " (registered trademark) (being trade name above) etc. of being sold by Mitsui Chemicals, Inc, suitably can use them.

In addition, as above-mentioned acrylic resin, methyl methacrylate system resin can be used aptly.Be the polymkeric substance of more than 50 % by weight from the content of the structural unit of methyl methacrylate when methyl methacrylate system resin refers to and resin total amount is decided to be 100 % by weight.Structural unit from methyl methacrylate preferably contains more than 70 % by weight in resin entirety.In addition, also can be imperplex methyl methacrylate being polymerized separately and obtaining.

If methyl methacrylate system resin as mentioned above in resin containing more than 50 % by weight from the structural unit of methyl methacrylate, can be just methyl methacrylate and can with the multipolymer of the monomer of its copolymerization.As can with the monomer of methyl methacrylate copolymer, the methacrylate beyond the methyl methacrylates such as such as β-dimethyl-aminoethylmethacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-Ethylhexyl Methacrylate and 2-hydroxyethyl methacrylate can be enumerated; The acrylate such as methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-EHA and acrylic acid 2-hydroxy methacrylate; The unsaturated acid such as methacrylic acid and acrylic acid; The halogenated styrenes such as chlorostyrene and bromstyrol; The substituted phenylethylenes such as the ring-alkylated styrenes of vinyltoluene, α-methyl styrene and so on; Vinyl cyanide, methacrylonitrile, maleic anhydride, phenyl maleimide, N-cyclohexylmaleimide etc.Above-mentioned monomer can individually use, and also can combinationally use two or more.

Rubber-like polymer can be added in above-mentioned methyl methacrylate system resin.By the interpolation of rubber-like polymer, acrylic resin film limbers up.Thereby, it is possible to limit applies tension force limit and batches in the operation of film and avoid concentrating at the part generation stress of film and cracking in film end or film is cut off such problem, therefore, it is possible to manufacture film with high yield when film is shaped.In addition, when the laminating with polarizing coating, film also can be suppressed to produce and break, avoid the problem that film is cut-off, therefore the operation transfiguration of film is easy.

As rubber-like polymer, acrylic acid series multilayer structure polymer can be enumerated, make ethylenically unsaturated monomers graft polymerization in the graft copolymer etc. of rubber constituent.Acrylic acid series multilayer structure polymer has the layer of caoutchouc elasticity or elastomeric layer in inside and the multilayer structure making had as outermost hard layer.The layer of caoutchouc elasticity or elastomeric layer such as can be set as 20 ~ 60 % by weight with the weighing scale of rubber-like polymer entirety.Acrylic acid series multilayer structure polymer also can be the structure of the hard layer also had as innermost layer.

The layer of caoutchouc elasticity or elastomeric layer comprise the layer of glass transition temperature (Tg) less than the acrylic acid series polymeric compounds of 25 DEG C.Forming the layer of caoutchouc elasticity or the acrylic acid series polymeric compounds of elastomeric layer is by by (methyl) lower alkyl acrylate, (methyl) acrylic acid lower alkoxy ester, (methyl) cyano ethyl acrylate, acrylamide, more than one and (methyl) allyl acrylate of the Mono-olefinic unsaturated monomers such as (methyl) dihydroxypropyl lower alkyl esters and (methyl) acrylic acid, ethylene glycol bisthioglycolate (methyl) acrylate, butylene glycol two (methyl) acrylate, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, diallyl maleate, trimethylolpropane tris (methyl) acrylate, the cross-linked polymer that the polyfunctional monomers such as allyl cinnamate are polymerized together and obtain.

Hard layer comprises the layer that Tg is the acrylic acid series polymeric compounds of more than 25 DEG C.As this acrylic acid series polymeric compounds, can enumerate and there is homopolymer that carbon number is the alkyl methacrylate of the alkyl of 1 ~ 4 and can the monofunctional monomer of copolymerization carry out the multipolymer etc. of copolymerization for principal ingredient with other alkyl methacrylate, alkyl acrylate, styrene, substituted phenylethylene, vinyl cyanide, methacrylonitrile etc. with this alkyl methacrylate.In addition, the acrylic acid series polymeric compounds forming hard layer can be the cross-linked polymer carrying out add polyfunctional monomer further in this monofunctional monomer after being polymerized.As such acrylic acid series polymeric compounds, such as, can enumerate the acrylic acid series polymeric compounds recorded in Japanese Patent Publication 55-27576 publication, Japanese Unexamined Patent Publication 6-80739 publication and Jap.P. No. 987868 publication.

Make ethylenically unsaturated monomers graft polymerization in rubber constituent graft copolymer preferably containing 5 ~ 80 % by weight the structural unit from the rubber constituent structural unit from ethylenically unsaturated monomers of 95 ~ 20 % by weight (therefore, containing).As rubber constituent, such as, can use: the diene series rubbers such as polybutadiene rubber, acrylonitrile/butadiene copolymer rubber, styrene/butadiene copolymers rubber; The acrylic rubber such as butyl polyacrylate, polyacrylic acid propyl ester, polyacrylic acid 2-Octyl Nitrite; And ethylene/propene/non-conjugated dienes system rubber etc.As rubber constituent, two or more compositions can be used.As ethylenically unsaturated monomers, styrene, vinyl cyanide, (methyl) alkyl acrylate etc. can be enumerated, wherein, preferably use the acrylic acid series unsaturated monomer such as vinyl cyanide, (methyl) alkyl acrylate.As this graft copolymer, the graft copolymer recorded in Japanese Laid-Open Patent Publication 55-147514 publication, Japanese Patent Publication 47-9740 publication can be used.

The diaphragm comprising above-mentioned acrylic resin has when implementing the operation making diaphragm contact with water described later the trend being easy to show the effect improving cementability.

Above-mentioned cellulose-based resin refers to cellulosic partial esterification thing or complete carboxylate, such as, can enumerate cellulosic acetic acid esters, propionic ester, butyric ester and their mixed ester etc.More specifically, triacetyl cellulose, diacetyl cellulose, cellulose-acetate propionate, cellulose acetate-butyrate etc. can be enumerated.Wherein, from cementability and easy acquired, triacetyl cellulose is applicable.

Cellulose-based resin molding can obtain commercially available product, such as, can enumerate " Fujitac (registered trademark) TD80 ", " Fujitac (registered trademark) TD80UF " and " Fujitac (registered trademark) TD80UZ " of Fuji Photo Film Co., Ltd., " KC8UX2M " and " KC8UY " (being trade name above) etc. of KonicaMinolta Co., Ltd..

Diaphragm is preferably less than 200 μm from the slim light-weighted viewpoint of polarization plates, is more preferably less than 100 μm, and preferably more than 20 μm, be more preferably more than 30 μm.In manufacture method of the present invention, such as, use the drum diaphragm long diaphragm being wound in reel.

(ultraviolet hardening bonding agent)

Bonding agent for the formation of the bond layer between diaphragm and polarizing coating can enumerate water system bonding agent and ultraviolet hardening bonding agent usually, uses ultraviolet hardening bonding agent in the present invention.

As ultraviolet hardening bonding agent, if classify according to its curing type, then can enumerate radical polymerization mould assembly bonding agent, cationic polymerization type bonding agent etc., if classify according to the chemical species of cure component, then can enumerate acrylic resin system bonding agent, epoxy bonding agent etc.In the present invention, any kind in these can be used, potpourris two or more in them can be used in addition, but the viewpoint such as easy to operate, the bonding strength that obtains is set out calmly, preferably uses the epoxy bonding agent of cationic polymerization type.Herein, epoxy resin refers in molecule, to have epoxy radicals, by the compound that is cured with the polyreaction of epoxy ring-opening or polymkeric substance, according to the convention in this field, even if monomer is also referred to as epoxy resin.

As the epoxy resin contained in ultraviolet hardening bonding agent, from viewpoints such as weatherability, refractive index and cationically polymerizables, be preferably used in the epoxy resin not containing aromatic ring in molecule.As the epoxy resin not containing aromatic ring in molecule, hydrogenated epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin etc. can be enumerated.

Hydrogenated epoxy resin obtains by following method: aromatic epoxy resin is optionally carried out core hydrogenation in the presence of a catalyst and under the condition of pressurization.As aromatic epoxy resin, such as, the bisphenol-type epoxy resins such as bisphenol A diglycidyl ether, Bisphenol F diglycidyl ether and bisphenol-S diglycidyl ether can be enumerated; The epoxy resin of the novolac type such as phenol novolac type epoxy resin, cresol novalac type epoxy resin and hydroxy benzaldehyde phenol novolac type epoxy resin; The epoxy resin etc. of the multifunctional types such as the glycidol ether of tetrahydroxy benzene methylmethane, the glycidol ether of tetrahydroxybenzophenone and epoxidation polyvinylphenol.Wherein, as hydrogenated epoxy resin, preferably use the bis-phenol A glycidyl ether of hydrogenation.

Alicyclic epoxy resin refers to have the epoxy resin that more than 1 is bonded to the epoxy radicals of ester ring type ring in molecule.The epoxy radicals being bonded to ester ring type ring refers to as shown in the formula shown in (I), two associative keys of epoxy radicals (-O-) respectively with 2 carbon atom (normally adjacent carbon atom) Direct Bonding forming ester ring type ring.In following formula (I), m is the integer of 2 ~ 5.

[changing 1]

Have the (CH in above-mentioned formula (I) ₂) _min hydrogen atom removing one or more after the compound of group of form can become alicyclic epoxy resin.The hydrogen forming ester ring type ring suitably can be replaced by the straight-chain such as methyl, ethyl alkyl.Wherein, there is the cyclopentane epoxide structure structure of m=3 [the above-mentioned formula (I) in], the epoxy resin of the 7-oxa-bicyclo[4.1.0 structure structure of m=4 [in the above-mentioned formula (I)] preferably uses owing to can provide the bonding agent of the bonding strength excellence between polarizing coating and diaphragm.Disclose the concrete example of alicyclic epoxy resin below.At this, first enumerate compound name, display afterwards and each self-corresponding chemical formula, to compound name and the chemical formula corresponding with it mark same-sign.

A:3,4-7-oxa-bicyclo[4.1.0 formic acid 3,4-epoxycyclohexanecarboxylate,

B:3,4-epoxy-6-cyclohexanecarboxylic acid 3,4-epoxy-6-methylcyclohexyl methyl esters,

C: ethylene (3,4-7-oxa-bicyclo[4.1.0 formic ether),

D: hexane diacid two (3,4-epoxycyclohexyl-methyl) ester,

E: hexane diacid two (3,4-epoxy-6-methylcyclohexylmethyl) ester,

F: diethylene glycol two (3,4-epoxycyclohexyl-methyl ether),

G: ethylene glycol bisthioglycolate (3,4-epoxycyclohexyl-methyl ether),

H:2,3,14,15-diepoxy-7,11,18,21-tetra-oxa-three spiral shell [5.2.2.5.2.2] heneicosane,

I:3-(3,4-epoxycyclohexyl)-8,9-epoxy-1,5-dioxo spiro [5.5] undecane,

J:4-vinyl cyclohexene dioxide,

K: citrene dioxide,

L: two (2,3-epoxycyclopentyl) ether,

M: dicyclopentadiene dioxide etc.

[changing 2]

Wherein, from being easier to reasons such as obtaining, preferred ethylene glycol bisthioglycolate (3,4-epoxycyclohexyl-methyl ether).

In addition, as above-mentioned aliphatic epoxy resin, the polyglycidyl ether of aliphatic polyol or its alkylene oxide adducts can be enumerated.More specifically, the diglycidyl ether of BDO can be enumerated; The diglycidyl ether of 1,6-hexanediol; The triglycidyl ether of glycerine; The triglycidyl ether of trimethylolpropane; The diglycidyl ether of polyglycol; The diglycidyl ether of propylene glycol; And, the monoglycidyl ether etc. of the aliphatic polyols such as ethylene glycol, propylene glycol and glycerine.

In the present invention, epoxy resin can only be used alone a kind, also can be used together two or more.

As the yardstick of the amount of the epoxy radicals of each epoxy resin of expression, there is epoxide equivalent.Epoxide equivalent refers to the quality of the resin comprising 1 equivalent epoxy radicals, can judge that amount of functional groups is many when numerical value is low.The assay method of epoxide equivalent is as follows: the epoxy specimens of accurate weighing is dissolved in chloroform, after adding acetic acid and tetraethylammonium bromide acetic acid solution, utilizes 0.1mol/L perchloric acid acetic acid titer to carry out potential difference (PD) titration.If carry out the dropping of perchloric acid-acetic acid titer, then perchloric acid and tetraethylammonium bromide react and generate hydrogen bromide.The hydrogen bromide generated and epoxy reaction.All epoxy radicals react thus hydrogen bromide is excessive time carry out end point determination, thus measure epoxide equivalent.

The epoxide equivalent of the epoxy resin used in the present invention usually in the scope of 30g ~ 3000g/ equivalent, preferably in the scope of 50g ~ 1500g/ equivalent.If epoxide equivalent is lower than 30g/ equivalent, then deposit the possibility that pliability reduces or bonding strength reduces of bond layer after hardening.On the other hand, if more than 3000g/ equivalent, then there is the possibility reduced with the compatibility of other composition that contains in bonding agent.

In the present invention, as mentioned above, epoxy resin is preferably the epoxy resin that its curing type is cationic polymerization.Therefore, ultraviolet hardening bonding agent preferably comprises Cationic photoinitiator.Cationic photoinitiator produces kation kind or lewis acid under the effect of Ultraviolet radiation, causes the polyreaction of epoxy radicals.The cationic polymerization initiators of any kind can be used.

The method that interpolation Cationic photoinitiator, irradiation ultraviolet radiation make bonding agent solidify is favourable in the following areas: the aspect can solidifying, not easily produce because of the heat of polarizing coating form and aspect change at normal temperatures; And can with the aspect of the bonding diaphragm of high-adhesive-strength and polarizing coating.Cationic photoinitiator produces catalytic action by light, even if therefore mixed in the epoxy, bonding agent also has excellent storage stability and operability.

As Cationic photoinitiator, be not particularly limited, such as, can enumerate aromatic diazonium salt; The salt such as aromatic iodonium salts and aromatic series sulfosalt; Iron-arene complex etc.

As aromatic diazonium salt, such as, can enumerate benzene diazonium hexafluoro antimonate, benzene diazonium hexafluorophosphate, benzene diazonium hexafluoro borate etc.

As aromatic iodonium salts, such as, can enumerate diphenyl iodine four (pentafluorophenyl group) borate, diphenyl iodine hexafluorophosphate, diphenyl iodine hexafluoro antimonate, two (4-nonyl phenyl) iodine hexafluorophosphate etc.

As aromatic series sulfosalt, such as, can enumerate triphenyl sulphur hexafluorophosphate, triphenyl sulphur hexafluoro antimonate, triphenyl sulphur four (pentafluorophenyl group) borate, 4,4 '-bis-(diphenyl sulfonium) diphenyl sulfide two (hexafluorophosphate), 4,4 '-bis-[two (beta-hydroxy ethoxy) phenyl sulfonium] diphenyl sulfide two (hexafluoro antimonate), 4,4 '-bis-[two (beta-hydroxy ethoxy) phenyl sulfonium] diphenyl sulfide two (hexafluorophosphate), 7-[two (p-methylphenyl) sulfonium]-ITX hexafluoro antimonate, 7-[two (p-methylphenyl) sulfonium]-ITX four (pentafluorophenyl group) borate, 4-phenylcarbonyl group-4 '-diphenyl sulfonium-diphenyl sulfide hexafluorophosphate, 4-(to tert-butyl-phenyl carbonyl)-4 '-diphenyl sulfonium-diphenyl sulfide hexafluoro antimonate, 4-(to tert-butyl-phenyl carbonyl)-4 '-two (p-methylphenyl) sulfonium-diphenyl sulfide four (pentafluorophenyl group) borate etc.

As iron-arene complex, such as, can enumerate dimethylbenzene-cyclopentadienyl group iron (II) hexafluoro antimonate, isopropyl benzene-cyclopentadienyl group iron (II) hexafluorophosphate, dimethylbenzene-cyclopentadienyl group iron (II)-three (trifyl) methanides etc.

The commercially available product of these Cationic photoinitiators can easily obtain, such as, can enumerate by trade name respectively " KAYARAD (registered trademark) PCI-220 " of Nippon Kayaku K. K, " KAYARAD (registered trademark) PCI-620 ", " UVI-6990 " of Dow Chemical, " ADEKAOPTMER (registered trademark) SP-150 " of ADEKA Corp., " ADEKAOPTMER (registered trademark) SP-170 ", " CI-5102 " of Tso Tat Co., Ltd., Japan, " CIT-1370 ", " CIT-1682 ", " CIP-1866S ", " CIP-2048S ", " CIP-2064S ", " DPI-101 " of green KCC, " DPI-102 ", " DPI-103 ", " DPI-105 ", " MPI-103 ", " MPI-105 ", " BBI-101 ", " BBI-102 ", " BBI-103 ", " BBI-105 ", " TPS-101 ", " TPS-102 ", " TPS-103 ", " TPS-105 ", " MDS-103 ", " MDS-105 ", " DTS-102 ", " DTS-103 ", " PI-2074 " of Rhodia Inc. etc.Wherein, " CI-5102 " of Tso Tat Co., Ltd., Japan is one of preferred Cationic photoinitiator.

Above-mentioned Cationic photoinitiator both can individually use, and two or more may be used in combination.Among them, especially preferably use aromatic series sulfosalt, even if because also there is Ultraviolet Light in the wavelength coverage of more than 300nm, thus curability excellence can be provided, there is good physical strength or the solidfied material of bonding strength.

The use level of Cationic photoinitiator is generally 0.5 ~ 20 weight portion relative to epoxy resin 100 weight portion, is preferably more than 1 weight portion, is preferably below 15 weight portions in addition.If the use level of this Cationic photoinitiator is lower than 0.5 weight portion, then there is solidification insufficient, the tendency that physical strength, bonding strength reduce.In addition, if the use level of Cationic photoinitiator is more than 20 weight portions, then there is the possibility of the hydroscopicity raising of solidfied material or the endurance quality reduction of polarization plates because the ionic substance in solidfied material increases.

When using Cationic photoinitiator, as required, ultraviolet hardening bonding agent can contain photosensitizer further.By using photosensitizer, the reactivity of cationic polymerization improves, and the physical strength of solidfied material, bonding strength can be made to improve.As photosensitizer, such as, carbonyls, organosulfur compound, persulfide, redox based compound, azo and diazo-compounds, halogen compounds, photo-reduction pigment etc. can be enumerated.As concrete example, such as, can enumerate benzoin methylether, benzoin iso-propylether and α, the benzoin derivatives such as alpha, alpha-dimethyl oxygen base-α-phenyl acetophenone; The benzophenone derivates such as benzophenone, 2,4-dichloro benzophenones, o-benzoyl yl benzoic acid methyl esters, 4,4 '-bis-(dimethylamino) benzophenone and 4,4 '-bis-(diethylamino) benzophenone; The thioxanthone derivates such as CTX and ITX; The anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; The acridone derivativeses such as N-methylacridine ketone and N-butyl acridone; And α, α-diethoxy acetophenone, benzil, Fluorenone, xanthone, uranyl compound, halogen compounds etc.But be not limited thereto.These photosensitizers can individually use, also can be used in combination two or more.The content of photosensitizer is preferably in the scope of 0.1 ~ 20 weight portion in ultraviolet hardening bonding agent 100 weight portion.

Ultraviolet hardening bonding agent also can contain the compound that oxetanes, vinyl ether, polyvalent alcohol etc. promote cationic polymerization further.

Oxetanes is the compound in molecule with quaternary cyclic ethers.As the example of oxetanes, 3-ethyl-3-hydroxymethyl oxetane, Isosorbide-5-Nitrae-bis-[(3-ethyl-3-oxetanyl) methoxy] benzene, 3-ethyl-3-(phenoxymethyl) oxetanes, two [(3-ethyl-3-oxetanyl) methyl] ether, 3-ethyl-3-(2-Ethylhexoxymethyl) oxetanes, phenol novolac type oxetanes etc. can be enumerated.The commercially available product of these oxetanes can easily obtain, such as, " ARONOXETANE (registered trademark) OXT-101 ", " ARONOXETANE (registered trademark) OXT-121 ", " ARONOXETANE (registered trademark) OXT-211 ", " ARONOXETANE (registered trademark) OXT-221 " and " ARONOXETANE (registered trademark) OXT-212 " etc. of Toagosei Co., Ltd all can be enumerated by trade name.The content of oxetanes is generally 5 ~ 95 % by weight, is preferably the ratio of 30 ~ 70 % by weight in ultraviolet hardening bonding agent.

As vinyl ether, the monofunctional vinyl ether with a vinyl and the polyfunctional vinyl ether in molecule with more than two vinyl can be used in molecule.In addition, the vinyl ether containing other functional group different from vinyl as hydroxyl, carboxyl, epoxy radicals etc. can also be used as required.

As the concrete example of monofunctional vinyl ether, propyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, bicyclopentadiene vinyl ether, tristane vinyl ether, benzyl vinyl ether, Acetoxyethyl vinyl ether, acetyl oxybutylvinyl ether, acetyl cyclohexane dimethanol monovinyl ether, acetyl group diethylene glycol monovinyl base ether can be enumerated.In addition, as the concrete example of vinyl ether with hydroxyl, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl base ether, diethylene glycol monovinyl base ether, 1,4-CHDM mono vinyl ether, dipropylene glycol mono vinyl ether can be enumerated.As the vinyl ether with epoxy radicals, glycidoxypropyl ethyl vinyl ether, glycidoxypropyl butyl vinyl ether, glycidyl cyclohexanedimethanol mono vinyl ether, glycidyl diethylene glycol monovinyl base ether etc. can be enumerated.

As the concrete example of difunctional vinyl ether, ethylene glycol divinyl ether, propylene glycol divinyl ether, 1 can be enumerated, ammediol divinyl ether, 1,4-butylene glycol divinyl ether, 1,5-PD divinyl ether, diethylene glycol divinyl ether, triethyleneglycol divinylether, TEG divinyl ether, cyclohexanediol divinyl ether, cyclohexanedimethanol divinyl base ether, hydrogenated bisphenol A divinyl ether etc.Among these divinyl ether compounds, the divinyl ether of preference chain alkane diol or the divinyl ether of oligo alkylene glycols, if enumerate preferred divinyl ether according to reasons such as easy acquisitions, then have diethylene glycol divinyl ether.

As the concrete example of trifunctional vinyl ether, trimethylolpropane tris vinyl ether, ethoxylated trimethylolpropane trivinyl ether etc. can be enumerated.

Preferably there is not the polyvalent alcohol of the acidic-group beyond phenolic hydroxyl group in the molecule in above-mentioned polyvalent alcohol.As such polyvalent alcohol, such as, can enumerate the polyol compound, polyester polyol compound, polycaprolactone polyol compound, the polyol compound with phenolic hydroxyl group, polycarbonate polyol etc. without functional group beyond hydroxyl.The molecular weight of these polyvalent alcohols is generally more than 48, is preferably more than 62, more preferably more than 100, is preferably less than 1000 in addition.The content of polyvalent alcohol is generally less than 50 % by weight, is preferably the ratio of less than 30 % by weight in ultraviolet hardening bonding agent.

In ultraviolet hardening bonding agent only otherwise damaging effect of the present invention just can contain other adjuvant, such as ion-trapping agent, antioxidant, chain-transferring agent, sensitizer, tackifier, thermoplastic resin, filling agent, flowing regulator, plastifier, defoamer etc. further.In addition, as ion-trapping agent, such as, can enumerate mineral compound and their potpourris such as pulverous bismuth system, antimony system, magnesium system, aluminium system, calcium system and titanium system.As antioxidant, such as, can enumerate hindered phenol system antioxidant etc.

[manufacture method of polarization plates]

The feature of the manufacture method of polarization plates of the present invention is to possess following operation (a) ~ operation (d).

A operation that () makes diaphragm contact with water,

(b) the one side coated UV line curing type bonding agent being selected from least one film in diaphragm and polarizing coating to formed bond layer operation,

(c) make diaphragm and polarizing coating across bond layer stacked obtain stacked film thus operation and

D operation that () makes bond layer solidify to stacked film irradiation ultraviolet radiation.

In the following description, sometimes respectively the operation (a) that diaphragm is contacted with water is called " operation (a) ", the one side coated UV line curing type bonding agent at diaphragm is called " operation (b) " to the operation (b) forming bond layer, the operation (c) obtaining stacked film thus of diaphragm and polarizing coating being fitted by bond layer is called " operation (c) ", by stacked film irradiation ultraviolet radiation, the operation (d) that bond layer solidifies is called " operation (d) ".Each operation is described in detail.

< operation (a) >

In operation (a), diaphragm is contacted with water.This operation such as with making diaphragm by the groove of humidification, can being carried out with the method that the winding-up water such as steam or utilization spraying of jetting carries out like that in an atmosphere, also can carry out in water like that with being impregnated in by diaphragm in water.By this operation, the water percentage of such as diaphragm can be adjusted.When adjusting the water percentage of diaphragm; preferably carry out adjusting and make in the temperature of the manufacturing environment of polarization plates and the air of humidity (under atmosphere), the amount of moisture in diaphragm is higher than the water percentage (equilibrium moisture content) reaching equilibrium state in this atmosphere.Operation (a) can be carried out in the stage before operation (d) described later, also can initially carry out, can also carry out after operation (b) or operation (c), but preferably carry out before operation (b).It should be noted that, when carrying out operation (a) after operation (b) or operation (c), preferably carry out operation (a) in an atmosphere.

By operation (a), the improved polarization plates of cementability of polarizing coating and diaphragm can be obtained.Its effect is more remarkable when diaphragm is acrylic resin film.

When carrying out operation (a) in an atmosphere, preferably carry out the temperature of 25 ~ 80 DEG C, more preferably carry out at 25 ~ 50 DEG C, preferably further to carry out at 30 ~ 50 DEG C.If temperature is more than 80 DEG C, then diaphragm, ultraviolet hardening bonding agent or polarizing coating are likely deteriorated due to heat.In addition, if temperature is less than 25 DEG C, then the water percentage of diaphragm is difficult to improve.In addition, when carrying out operation (a) in an atmosphere, preferably carry out under the atmosphere of relative humidity 60 ~ 90%, more preferably carry out under the atmosphere of relative humidity 70 ~ 90%.If relative humidity is less than 60%, then the water percentage of diaphragm is difficult to improve.On the other hand, when relative humidity is more than 90%, diaphragm adheres to water droplet, it causes producing in unfavorable conditions such as diaphragm residuary water drop impression as reason, and excessive moisture likely impacts the solidification of bonding agent.

Processing time when carrying out operation (a) be in an atmosphere preferably more than 0.2 second, be more preferably more than 1 second, more preferably more than 5 seconds.In addition, the processing time be preferably less than 1 hour, be more preferably less than 10 minutes, more preferably less than 5 minutes.If the processing time was less than 0.2 second, then the cementability of bonding agent and polarizing coating has the trend that can not fully improve, if in addition more than 1 hour, then throughput rate is tending towards declining.

Manufacture method of the present invention can also comprise the operation (a-1) heated the diaphragm comprising thermoplastic resin before operation (a).Below, sometimes the operation heated the diaphragm comprising thermoplastic resin (a-1) is called " operation (a-1) ".

Operation (a-1) is carried out for making the convex-concave on diaphragm surface become uniform object.The temperature that film is heated be preferably the resin forming diaphragm glass transition temperature (Tg) temperature below, more preferably carry out the temperature of lower than glass transition temperature 5 ~ 45 DEG C.If temperature is too low, then has and be difficult to obtain the trend by the effect of Surface uniformization, in addition, at the temperature exceeding glass transition temperature, be sometimes difficult to transmit film in the manufacturing apparatus because film extends.In addition, the heat time be preferably more than 0.2 second, be more preferably more than 1 second, more preferably more than 5 seconds.In addition, the heat time be preferably less than 1 hour, be more preferably below 10 points of kinds, more preferably less than 5 minutes.The heating of diaphragm also because of the kind of film, manufacturing environment and different, is therefore carried out with suitable temperature, time according to adopted diaphragm.The heating of diaphragm is carried out usually under the noncontact condition not making diaphragm contact with water, under the atmosphere of such as relative humidity less than 20%.

Such as can enumerate the method that diaphragm heats: the diaphragm of the length pulled out by the diaphragm from drum is successively by the method in the groove of heating; The method etc. to the air of long diaphragm winding-up heating such as use fan blower.When carrying out operation (a-1), preferably make diaphragm to contact with water before carry out.By carrying out operation (a-1), the face quality of diaphragm can be improved, the polarization plates of surface for the face quality of homogeneous can be obtained.

In manufacture method of the present invention, when carrying out above-mentioned operation (a-1), after this operation (a-1), carry out the operation (a) that diaphragm is contacted with water.

Water percentage through the diaphragm of operation (a) described above is generally 0.2 ~ 5 % by weight, is preferably 0.4 ~ 2 % by weight, more preferably 0.6 ~ 1.6 % by weight.The enforcement of this water percentage and operation (a-1) has nothing to do, and is the scope after carrying out operation (a).

The water percentage of this diaphragm is the scaled value calculated based on the determination of moisture value measured by optical transmission method (using the value that infrared ray moisture content meter measures).In this instructions, the water percentage of diaphragm calculates as follows.First; prepare the diaphragm that the condition of several operations (a) is different; optical transmission method is utilized to measure these diaphragms; then dry weight method is passed through (105 DEG C of dryings 1 hour; water percentage is obtained according to the weight difference before and after dry) obtain the water percentage of these diaphragms, with the measured value based on optical transmission method and the water percentage production standard curve based on dry weight method.For the water percentage of diaphragm, calculate water percentage by referring to the typical curve made the measured value based on optical transmission method.

As infrared ray moisture content meter, such as, can use the infrared ray multicomponent meter (IM series IRMA1100S) etc. of diffuse reflection type infrared ray film thickness gauge (RX-300) of Kurashiki Boseki K.K., Chino Co., Ltd..

< operation (b) >

In operation (b), form bond layer at the one side coated UV line curing type bonding agent of the diaphragm after operation (a) and/or polarizing coating.Diaphragm after operation (a) is described above, is generally the water percentage of 0.2 ~ 5 % by weight.Bond layer can be formed at diaphragm with the binding face of polarizing coating; also that can be formed at polarizing coating with binding face that is diaphragm; also this two sides can be formed at, but in manufacture method of the present invention, that preferably bond layer is formed at diaphragm with binding face that is polarizing coating.The coating of bonding agent such as can utilize the various coating method such as scraper, line rod, mouth mould coating machine, comma coating machine, gravure coater.Each coating method has best range of viscosities separately, and the viscosity adjustment therefore using solvent to carry out bonding agent is also useful technology.Solvent preferably uses and the optical property of polarizing coating can not be made to decline and dissolve the solvent of bonding agent well.As the concrete example of solvent, be not particularly limited, such as, can enumerate the organic solvents such as the ester such as hydrocarbon, ethyl acetate such as toluene.

In operation (b), ultraviolet hardening bonding agent can be heated before carrying out coating.If heat ultraviolet hardening bonding agent, then viscosity declines, and is therefore easy to coat adherend, and making bonding agent solidification cementability that is rear and adherend improve, is therefore preferred.Can also heat after coating adhesive, now can improve the cementability with adherend after making bonding agent solidify.

It should be noted that, before forming bond layer, the easy bonding process such as corona treatment, Cement Composite Treated by Plasma, primary coat process, anchoring coating process can be implemented to the bond layer forming surface of diaphragm or polarizing coating.

< operation (c) >

In operation (c), by the bond layer formed in operation (b), diaphragm and polarizing coating laminating are obtained stacked film.Stacked film can for being laminated with the formation of diaphragm at the single or double of polarizing coating.When the two-sided stacked guard film of polarizing coating, two diaphragms can identical also can be obstructed.In addition, also can be laminated with diaphragm in a face of polarizing coating, be laminated with the formation of optical compensation films at polarizing coating another side.

< operation (d) >

In operation (d), to the stacked film irradiation ultraviolet radiation obtained in above-mentioned operation (c).By ultraviolet irradiation, make the bond layer solidification comprising ultraviolet hardening bonding agent.Ultraviolet light source can be used in below wavelength 400nm to be had and sends out such as low pressure mercury lamp, medium pressure mercury lamp, high-pressure sodium lamp, ultrahigh pressure mercury lamp, chemical lamp, black lamp, microwave-excited mercury lamp, metal halide lamp etc. photodistributed.

The photo-irradiation intensity of the bond layer comprising ultraviolet hardening bonding agent is determined according to the composition of ultraviolet hardening bonding agent, 0.1 ~ 500mW/cm is preferably to the exposure intensity of the effective wavelength coverage of the activation of polymerization initiator ².If photo-irradiation intensity is less than 0.1mW/cm ², then the reaction time is long, if more than 500mW/cm ², then due to the heating when heat that produced by lamp radiation and the polymerization of ultraviolet hardening bonding agent, the xanthochromia of bonding agent, polarizing coating deterioration is likely produced.The light irradiation time of the bond layer comprising ultraviolet hardening bonding agent is controlled according to the composition of each ultraviolet hardening bonding agent, be not particularly limited, but the long-pending accumulative light quantity being expressed as exposure intensity and irradiation time is preferably set to 10 ~ 5000mJ/cm ².If to the accumulative deficiency in light quantity 10mJ/cm of ultraviolet hardening bonding agent ², then the generation from the spike of polymerization initiator is insufficient, and being solidified with of bond layer may be insufficient.On the other hand, if more than 5000mJ/cm ², then irradiation time is very long, has and improves disadvantageous trend to throughput rate.

The solidification of the bond layer of Ultraviolet radiation is utilized preferably to carry out under the condition that the various functions of the polarization plates of the transparency of the degree of polarization of polarizing coating, transmissivity and form and aspect and diaphragm and optical compensation films and so on can not be made to reduce.The thickness of the bond layer after solidification is generally less than 50 μm, is preferably less than 20 μm, more preferably less than 10 μm.

Above operation (a-1), operation (a) ~ operation (d) are carried out usually in toilet.In addition, above operation (b) ~ operation (d) is carried out usually under the environment of temperature 20 DEG C ~ 27 DEG C, relative humidity 40% ~ 62%.

By manufacture method described above, polarization plates can be manufactured.This polarization plates both can be only in the formation of the single-sided lamination diaphragm of polarizing coating, also can in the formation of the two-sided laminating diaphragm of polarizing coating.

Only be laminated with in the polarization plates of diaphragm at the one side of polarizing coating, optical compensation films can be folded at polarizing coating with the surface layer of the opposition side, face being fitted with diaphragm.For fit polarizing coating and optical compensation films bonding agent such as can for containing polyvinyl alcohol resin or carbamate resins as the such bonding agent different types of with ultraviolet hardening bonding agent of the water system bonding agent of bonding agent composition, also can be ultraviolet hardening bonding agent.If use with for polarizing coating of the fitting bonding agent identical with the ultraviolet hardening bonding agent of diaphragm, then can enhance productivity and cut down raw material types.

As optical compensation films, cellulose-based resins such as comprising triacetyl cellulose (TAC) can be enumerated; The ethylene series resins such as tygon, polypropylene and Polyvinylchloride; The polyester based resin such as polyethylene terephthalate and PEN; The cyclic olefine resins such as norbornene resin; The optical compensation films of the acrylic resin such as polyacrylate and polymethylmethacrylate.

As the optical compensation films comprising cellulose-based resin molding, such as, can enumerate the film making above-mentioned cellulose-based resin molding contain the compound with adjusting offset function; Film after cellulose-based surface resin film coating has the compound of adjusting offset function; Uniaxial tension or biaxial stretch-formed and film etc. that is that obtain are carried out to cellulose-based resin molding.As the commercially available optical compensation films comprising cellulose-based resin molding, " KC4FR-1 ", " KC4HR-1 " (being trade name above) etc. of " WVFILMWideViewEA80 " of such as Fuji Photo Film Co., Ltd., KonicaMinoltaOpto Co., Ltd. can be enumerated.

The thickness comprising the optical compensation films of cellulose-based resin molding is not particularly limited, and is preferably in the scope of 20 ~ 90 μm, is more preferably in the scope of 30 ~ 90 μm.When thickness is less than 20 μm, film is difficult to process, and on the other hand, when thickness is more than 90 μm, processability is tending towards being deteriorated, and has disadvantageous trend in the slim lightweight of obtained polarization plates.

As the optical compensation films comprising cyclic olefine resin, such as can enumerate uniaxial tension or biaxial stretch-formed after cyclic olefine resin molding.When large-scale liquid crystal display television liquid crystal panel, especially possess vertical orientated (VA) pattern liquid crystal cell liquid crystal panel in use the polarization plates obtained by the present invention, as optical compensation films, the stretching product of cyclic olefine resin molding are also suitable from the aspect of optical characteristics and permanance.

Comprise the thickness of the optical compensation films of the cyclic olefine resin after stretching blocked up time processability be tending towards being deteriorated, and have that the transparency declines, polarization plates is difficult to the such trend of slim lightweight.Therefore, the thickness of film is preferably about 20 ~ 80 μm.

It should be noted that, optical compensation films similarly can implement corona treatment to bond layer forming surface with diaphragm and polarizing coating before formation bond layer, Cement Composite Treated by Plasma, primary coat process, anchoring be coated with easy bonding process such as processing.

Polarization plates described above can be formed for the adhesive phase (or bond layer) with liquid crystal cell laminating etc.Adhesive phase can be formed at the face with the opposition side, face of stacked guard film in diaphragm or polarizing coating.In addition, in polarizing coating, diaphragm or optical compensation films can be folded with the surface layer of the opposition side, face of stacked guard film, form adhesive phase (or bond layer) thereon.In addition, also can on polarizing coating, on the diaphragm be layered on polarizing coating or optical compensation films stacked optical functional film, this optical functional film is formed adhesive phase (or bond layer).

As the bonding agent used in this adhesive phase, known suitable bonding agent can be used, such as, can enumerate acrylic adhesive, carbamate system bonding agent, silicon-type bonding agent etc.Wherein, from viewpoints such as the transparency, bounding force, reliability, re-workabilities, preferably acrylic adhesive is used.Adhesive phase can be arranged as follows: by above-mentioned bonding agent making case as organic solvent solution; mouth mould coating machine, gravure coater etc. is utilized to be coated on base material film (such as diaphragm, polarizing coating etc.); make it dry, adhesive phase is set thus.In addition, also can be arranged by the method that upper for the plastic foil (being referred to as barrier film) after implementing the demoulding process sheet bonding agent formed is transferred to base material film.The thickness of adhesive phase is generally preferably in the scope of 2 ~ 40 μm.

Optical functional film can be layered in by adhesive phase on diaphragm stacked on polarizing coating, on polarizing coating or optical compensation films.As optical functional film, such as, can be set forth in the optical compensation films of substrate surface coating fluid crystalline compound orientation; Certain polarized light of transmission and reflection shows the reflective polarizing film of the polarized light of the character contrary with this polarized light; Comprise the phase retardation film of polycarbonate-based resin; Comprise the phase retardation film of cyclic olefine resin, the film of the anti-dazzle function of band that surface has concaveconvex shape; The film of belt surface anti-reflective function; Surface has the reflectance coating of reflection function; Have the semi-transparent anti-film etc. of reflection function and transmission function concurrently.

As being equivalent at substrate surface coating fluid crystalline compound and the commercially available product of the optical compensation films of orientation, " the WV film " sold by Fuji Photo Film Co., Ltd., " the NH film ", " NR film " sold by JX Kuang stone Energy KK etc. can be enumerated by trade name respectively.As being equivalent to certain polarized light of transmission and reflection shows the commercially available product of the reflective polarizing film of the polarized light of the character contrary with this polarized light, " DBEF ", " APF " that can obtain from Sumitomo 3M Co., Ltd. in Japan of such as 3M Inc. etc. can be enumerated respectively by trade name.In addition, as the commercially available product being equivalent to the phase retardation film comprising cyclic olefine resin, " Arton film " (" Arton " is the registered trademark of the said firm) of such as being sold by JSR Corp., " エ ス シ ー Na " (registered trademark) of being sold by Sekisui Chemical Co., Ltd, " ZEONOR film " (registered trademark) of being sold by Zeon Corp etc. can be enumerated by trade name respectively.

[liquid crystal indicator]

The polarization plates manufactured by the present invention is preferred for liquid crystal indicator.Liquid crystal indicator possesses liquid crystal panel.This liquid crystal panel possesses liquid crystal cell and is laminated in the polarization plates of single or double of this liquid crystal cell, and liquid crystal cell and polarization plates are fitted by adhesive phase as mentioned above.Liquid crystal panel is only when a mask of liquid crystal cell has the polarization plates manufactured by the present invention, and the polarization plates being arranged on liquid crystal cell another side can use known suitable polarization plates.In the liquid crystal panel that liquid crystal indicator possesses, the polarization plates being arranged on the front face side viewing side of the liquid crystal indicator (and the opposition side of backlight) of liquid crystal cell can be such as the polarization plates etc. after implementing non-glare treated, hard conating process, antireflection process.

In liquid crystal indicator, formation beyond liquid crystal panel can adopt the suitable formation of known liquid crystal indicator, such as can enumerate the formation possessing backlight, light diffusing board and liquid crystal panel successively, and possess the formation of backlight, light diffusing board, light diffusing patch and liquid crystal panel successively.

Manufacturing method according to the invention, absorbs moisture in the diaphragm after contacting in operation (a) with water, and the diaphragm absorbing moisture in operation (c) by bond layer and polarizing coating stacked.Think that the water function that absorbs in this diaphragm is in forming the ultraviolet hardening bonding agent of bond layer, polarizing coating and improve bonding force.

Embodiment

Below enumerate embodiment and more specific description is carried out to the present invention, but the invention is not restricted to these embodiments.It should be noted that, in example, represent that " % " and " part " of content and use amount just refers to weight basis as long as no special record.

In following example, the water percentage of diaphragm is the scaled value calculated based on the determination of moisture value measured by optical transmission method (using the value that infrared ray moisture content meter measures).Specifically; in advance the diaphragm of keeping stipulated time under the environment of temperature 23 DEG C, relative humidity 60% and the diaphragm under the environment of temperature 23 DEG C, relative humidity 90% after the keeping stipulated time are respectively prepared several, utilize the measured value based on optical transmission method of these diaphragms and the water percentage production standard curve based on dry weight method.Then; in embodiment; water percentage is calculated with the measured value reference standard curve in the optical transmission method of the diaphragm after water receiving operation; in comparative example, calculate water percentage with the measured value reference standard curve in the optical transmission method of the diaphragm of (temperature 23 DEG C, relative humidity 60%) before formation bond layer.It should be noted that, as infrared ray moisture content meter, use the infrared ray multicomponent meter (IM series IRMA1100S) of Chino Co., Ltd..

[Production Example 1: the making of diaphragm]

Ion exchange water 1700 parts, 0.7 part, sodium carbonate, sodium peroxydisulfate 0.3 part is dropped at the reaction vessel of the glass of internal volume 5L, stir under nitrogen flowing, drop into dialkyl sulfosuccinate sodium [product " PELEX (registered trademark) OT-P " of Kao Corp] 4.46 parts, ion exchange water 150 parts, methyl methacrylate 150 parts and allyl methacrylate 0.3 part.Afterwards, whipping temp is warming up to 75 DEG C, stirs 150 minutes.

Then, 90 minutes used times added the potpourri of the potpourri of butyl acrylate 689 parts, styrene 162 parts and allyl methacrylate 17 parts and sodium peroxydisulfate 0.85 part, " PELEX (registered trademark) OT-P " 7.4 parts and ion exchange water 50 parts, and then continuous polymerization 90 minutes.After being polymerized, so 30 minutes used times add the potpourri of methyl acrylate 326 parts and ethyl acrylate 14 parts and be dissolved with the ion exchange water 30 parts of sodium peroxydisulfate 0.34 part.Add after terminating, and then keep 60 minutes thus complete polymerization.Obtained reaction product is dropped in 0.5% aluminum chloride aqueous solution and makes polymer agglomerates.After it is cleaned 5 times with warm water, carry out drying, obtain acrylic acid series multiple layer polymer.

Methyl methacrylate/acrylic acid methyl esters polymerization than be 96/4, refractive index is add the acrylic acid series multiple layer polymer 20 parts above made in the multipolymer 80 parts of 1.49, obtained acrylic-based compositions Henschel mixer is mixed, carries out melting mixing with the single screw extrusion machine (screw rod footpath 65mm) of exhaust.Extrusion molding is carried out, with the diaphragm making extruded resin be crimped on to be set in the mode of the resilient roller of 80 DEG C to make thickness 80 μm by roller unit (3, elastic polished roller, horizontal forming roll) extrusion resin temperature 260 DEG C.It should be noted that, extrusion molding uses the wide 1400mm of lip and the T mouth mould of lip interval 1mm.

[Production Example 2: the making of polarizing coating]

By comprising average degree of polymerization about 2400, after the polyvinyl alcohol film of thickness 75 μm of polyvinyl alcohol (PVA) of saponification degree more than 99.9 % by mole impregnated in the pure water of 30 DEG C, the weight ratio that impregnated in iodine/potassium iodide/water is 0.02/2/100 and water temperature is the aqueous solution of 30 DEG C.Afterwards, the weight ratio that impregnated in potassium iodide/boric acid/water is 12/5/100 and water temperature is the aqueous solution of 56.5 DEG C.Then, after cleaning with the pure water of 8 DEG C, carry out drying at 65 DEG C, manufacture iodine gas absorption quantity in the polarizing coating of polyvinyl alcohol film.Stretch and mainly carry out in iodine staining and the acid-treated operation of boron, total stretching ratio is 5.3 times.

[Production Example 3: the preparation of ultraviolet hardening bonding agent]

As ultraviolet hardening bonding agent, use the epoxy bonding agent of cationic polymerization type.When it is prepared, the curability composition (A) comprised in bonding agent and Cationic photoinitiator (B) use following material.

(A) the curability composition comprised in bonding agent

(a1) alicyclic epoxy resin: 3,4-7-oxa-bicyclo[4.1.0 formic acid 3,4-epoxycyclohexanecarboxylate: be denoted as (a1) by the acquisition of Daicel chemical industry Co., Ltd., trade name " CELLOXIDE (registered trademark) 2021P ", table 1.

(a2) aliphatic epoxy resin: BDDE: be denoted as (a2) by the acquisition of NagaseChemtex Co., Ltd., trade name " Denacol (registered trademark) EX-121 ", table 1.

(a3) vinyl ether: diethylene glycol divinyl ether: be denoted as (a3) by Nippon Carbide Kogyo K.K's acquisition, table 1.

3 kinds of above-mentioned curability compositions are cationic polymerization type, are respectively the compound with following formula structure.

[changing 3]

(B) Cationic photoinitiator

Triarylsulfonium salt cation polymerization photoinitiator: with the form of 50% polypropylene carbonate ester solution by the acquisition of Sanapro (サ Application ア プ ロ) company, trade name " CPI-100P ".

By above-mentioned alicyclic epoxy resin (a1) 70 parts, aliphatic epoxy resin (a2) 15 parts and vinyl ether (a3) 15 parts mixing, and then with after the Cationic photoinitiator 4.5 parts shown in the mixing above of the form of solid constituent, carry out deaeration, prepare Photocurable adhesive agent liquid.Use the rotary determination of viscoelasticity device " PhysicaMCR301 " of AntonPaar Inc., to the viscosity during bonding agent mensuration temperature 25 DEG C prepared.The results are shown in table 1.

[embodiment 1]

The diaphragm obtained in Production Example 1 is put into and is set as temperature 40 DEG C, constant temperature and humidity oven heat 1 hour [operation (a)] that humidification becomes relative humidity 90%.The water percentage of the diaphragm after this operation is 1.2%.Next, Corona discharge Treatment is implemented to the surface of diaphragm, is coated on the ultraviolet hardening bonding agent obtained in Production Example 3 in this Corona discharge Treatment face, defines bond layer [operation (b)].In addition, the ultraviolet hardening bonding agent that obtains in Production Example 3 is coated on to form bond layer [operation (b)] at the one side of cyclic olefine resin molding [trade name " ZEONOR film " (registered trademark) of Zeon Corp] concurrently therewith.Afterwards; under the environment of 23 DEG C, diaphragm and cyclic olefine resin molding are fitted in the two-sided of the polarizing coating obtained in Production Example 2 respectively by bond layer, obtain the stacked film [operation (c)] comprising acrylic resin film/bond layer/polarizing coating/bond layer/cyclic olefine resin molding.Then by cyclic olefine resin face irradiation ultraviolet radiation, bond layer is solidified, made polarization plates [operation (d)].

[embodiment 2]

The diaphragm obtained in Production Example 1 is put into and is set as temperature 30 DEG C, constant temperature and humidity oven heat 20 second [operation (a)] that humidification becomes relative humidity 60%, made polarization plates similarly to Example 1 in addition.The water percentage of diaphragm is 0.8%.

[comparative example 1]

The diaphragm obtained in Production Example 1 is put into constant temperature oven 60 second being set as temperature 95 DEG C, divided by having made polarization plates similarly to Example 1 in addition.The water percentage of the diaphragm after taking out from baking oven is 0.1%.It should be noted that, the relative humidity in constant temperature oven is less than 10%.

[comparative example 2]

The diaphragm obtained in Production Example 1 is not heated and does not carry out operation (a) yet, made polarization plates similarly to Example 1 in addition.The water percentage of the diaphragm after taking out from baking oven is 0.3%.

(180 degree of disbonded tests of polarization plates)

For the polarization plates made in the above embodiments and comparative example, determine the peel strength between diaphragm and polarizing coating as follows.Made polarization plates is left standstill 300 hours after manufacturing, and the size cutting into 200mm × 25mm makes test film.Being determined as follows of peel strength between the diaphragm obtained in Production Example 1 and polarizing coating is carried out: the exposure of the diaphragm obtained in Production Example 1 arranges the adhesive phase of acrylic acid series; glass plate is fitted in by this adhesive phase; the tooth shape of inserting cutting knife between polarizing coating with the diaphragm obtained in Production Example 1 becomes otch; in the longitudinal direction diaphragm is peeled off 30mm from end, the clamping part of the part testing machine of this stripping is clamped.The test film of this state is carried out 180 degree of disbonded tests according to JISK6854-2:1999 " bonding agent-stripping bonding strength test method-2: 180 degree stripping " to clamp translational speed 300mm/ minute in the atmosphere of temperature 23 DEG C, relative humidity 55%, obtains the Average peel force of the 170mm length of the 30mm not comprising clamping part.The results are shown in table 1.

[table 1]

(footnote of table 1)

Cure component

(a1): 3,4-7-oxa-bicyclo[4.1.0 formic acid 3,4-epoxycyclohexanecarboxylate: " CELLOXIDE2021P " of Daicel chemical industry Co., Ltd..

(a2): BDDE: " DenacolEX-121 " of NagaseChemtex company.

(a3): diethylene glycol divinyl ether: obtained by Nippon Carbide Kogyo K.K.

For the diaphragm and the polarizing coating that carry out the stripping after 180 degree of disbonded tests in each embodiment and comparative example; by FT-IR device (Varian Inc. " 640-IR "); measure the infrared absorption spectrum of respective release surface, investigate whether remain bonding agent.Its result, embodiment 1 and embodiment 2 be not residual bonding agent in diaphragm side, only remains bonding agent in polarizing coating side.Thus, think and there occurs stripping between bond layer and diaphragm.In addition, comparative example 1 and comparative example 2 be not residual bonding agent in polarizing coating side, only remains bonding agent in diaphragm side.Thus, think and there occurs stripping between bond layer and polarizing coating.

According to the result of table 1, the embodiment 1 and 2 after carrying out operation (a) to diaphragm shows good cementability in 180 degree of disbonded tests.On the other hand, to compare cementability low with embodiment 1 and 2 with 2 for the comparative example 1 not carrying out operation (a) to diaphragm.Can confirm thus, if carry out water receiving process to diaphragm, especially acrylic resin film, then the cementability that can obtain between polarizing coating and diaphragm improves such effect.

Claims (9)

1. the manufacture method of a polarization plates; it is characterized in that; it utilizes ultraviolet hardening bonding agent, and in polyvinyl alcohol resin film, gas absorption quantity has the diaphragm that formed by thermoplastic resin and manufacture the method for polarization plates of at least simultaneously fitting of the polarizing coating of iodine or dichroic dye

The manufacture method of described polarization plates possesses:

Make the operation (a) that described diaphragm contacts with water;

At least one film in the diaphragm be selected from after described operation (a) and polarizing coating is formed the operation (b) comprising the bond layer of ultraviolet hardening bonding agent;

Make diaphragm and polarizing coating across the stacked operation (c) obtaining stacked film of described bond layer; And

To the operation (d) that described stacked film irradiation ultraviolet radiation makes bond layer solidify.

2. the manufacture method of polarization plates as claimed in claim 1, wherein,

The operation (a-1) that described diaphragm is heated was comprised before the described operation (a) making diaphragm contact with water.

3. the manufacture method of polarization plates as claimed in claim 1, wherein,

Described ultraviolet hardening bonding agent is heated before formation bond layer.

4. the manufacture method of polarization plates as claimed in claim 1, wherein,

Described ultraviolet hardening bonding agent is epoxy bonding agent.

5. the manufacture method of polarization plates as claimed in claim 4, wherein,

Described epoxy bonding agent is included in the epoxy resin not containing aromatic ring in molecule.

6. the manufacture method of polarization plates as claimed in claim 4, wherein,

Described epoxy bonding agent comprises described epoxy resin and Cationic photoinitiator.

7. the manufacture method of the polarization plates according to any one of claim 1 ~ 6, wherein,

Described thermoplastic resin is acrylic resin.

8. the manufacture method of polarization plates as claimed in claim 7, wherein,

The water percentage of the described diaphragm after described operation (a) is 0.2 ~ 5 % by weight.

9. the manufacture method of a polarization plates; it is characterized in that; it utilizes ultraviolet hardening bonding agent, and in polyvinyl alcohol resin film, gas absorption quantity has the diaphragm that formed by thermoplastic resin and manufacture the method for polarization plates of at least simultaneously fitting of the polarizing coating of iodine or dichroic dye

The manufacture method of described polarization plates possesses:

Be selected from water percentage be 0.2 ~ 5 % by weight diaphragm and polarizing coating at least one film on formed and comprise the operation (b) of the bond layer of ultraviolet hardening bonding agent;

Make diaphragm and polarizing coating across the stacked operation (c) obtaining stacked film of described bond layer; And

To the operation (d) that described stacked film irradiation ultraviolet radiation makes bond layer solidify.