JP5586174B2 - Optical laminate and method for producing the same - Google Patents

Description

  The present invention relates to an optical laminate used for a liquid crystal display device. More specifically, a polarizing plate is laminated on a liquid crystal cell substrate made of glass, plastic sheet or the like constituting the liquid crystal display device via an adhesive layer. It is related with the optical laminated body which becomes. Moreover, this invention relates to the manufacturing method of this optical laminated body.

  The polarizing plate is useful as an optical component constituting a liquid crystal display device. Conventionally, a polarizing plate has a structure in which a protective layer made of a transparent resin film is laminated on one or both sides of a polarizing film using an aqueous adhesive or the like. As such a transparent resin film, a triacetyl cellulose film (TAC film) is often used because of its excellent optical transparency and moisture permeability. Even when the protective layer is provided only on one side of the polarizing film, a resin film having an optical function such as a retardation function is provided on the other side of the polarizing film, which also serves as a protective function for the polarizing film. It is often laminated via. The polarizing plate configured as described above is bonded to a liquid crystal cell with an adhesive via another optical function layer as necessary, and is assembled into a liquid crystal display device as a liquid crystal panel.

  Applications of liquid crystal display devices are rapidly expanding as thin display screens such as liquid crystal televisions, liquid crystal monitors, and personal computers. In such expansion of applications, further reduction in thickness is also required for members constituting the same. As described above, a polarizing plate is generally bonded to a liquid crystal cell using an adhesive. However, if there is any inconvenience after bonding, this is easily peeled off from the liquid crystal cell and another polarizing plate is pasted. Because it is convenient to match. However, the pressure-sensitive adhesive usually needs to have a thickness of at least about 20 μm in order to maintain an appropriate pressure-sensitive adhesive force, which is a bottleneck for reducing the thickness of a liquid crystal panel or a liquid crystal display device.

  There is also an attempt to reduce the thickness of the polarizing film by omitting the liquid crystal cell side protective layer, forming an adhesive layer directly on the polarizing film, and bonding the adhesive layer to the liquid crystal cell. However, in the state where the polarizing film and the liquid crystal cell are directly bonded with the pressure-sensitive adhesive layer as described above, when the heat resistance test exposed to a high temperature is performed, the pressure-sensitive adhesive layer alone cannot sufficiently absorb the contraction of the polarizing film, Defects such as floating, peeling or foaming may occur between the polarizing film and the pressure-sensitive adhesive layer. In addition, when a thermal shock test (heat shock test) that repeats a high temperature state and a low temperature state was performed, the adhesive film alone could not sufficiently absorb the expansion and contraction of the polarizing film, and the polarizing film sometimes cracked. .

  As another attempt to reduce the thickness of the polarizing plate, for example, in Patent Document 1, an uncured epoxy resin composition is applied to at least one surface of a polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin. Thereafter, a technique for forming a protective film by curing the composition is disclosed. However, in a state where a polarizing plate having a cured product of an epoxy resin composition as a protective film is bonded to a liquid crystal cell via an adhesive, the durability is not sufficient, for example, when a heat shock test is performed, The polarizing film sometimes broke. In Patent Document 2, a protective film is attached to a polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin via an adhesive composed of an epoxy resin containing no aromatic ring as a main component. In other words, a technique for forming a polarizing plate is disclosed.

  On the other hand, in Patent Document 3, a photosensitizer, acryloyl, terpolymer of ethylene, an acrylate-based and / or methacrylate-based monomer, and maleic acid and / or maleic anhydride are formed on one surface of a polarizing film. An adhesive layer made of a photocurable adhesive in which a predetermined amount of an unsaturated compound such as an oxy group-containing compound is mixed is formed into a polarizing plate with an adhesive layer, and the polarizing plate is attached to the liquid crystal cell substrate via this adhesive layer. The technique which adhere | attaches is disclosed, and providing the protective layer which consists of said photocurable adhesive on the other surface of a polarizing film is also described. However, when the polarizing plate is bonded to the liquid crystal cell substrate through the adhesive disclosed in this document, no major problems are seen in the small size liquid crystal cell in the heat resistance test and heat shock test, but the medium size to the large size. In the liquid crystal cell of a size, there existed a problem that a polarizing plate peeled from the liquid crystal cell substrate surface, or a polarizing film cracked.

  Patent Document 4 discloses a technique in which a polarizing plate is supplied from a roll via an adhesive and directly bonded to a liquid crystal cell substrate.

JP 2004-245924 A JP 2004-245925 A Japanese Patent No. 3695484 (Japanese Patent Laid-Open No. 9-159828) Japanese Patent No. 4093891 (Japanese Patent Laid-Open No. 2004-4636)

  The objective of this invention is providing the optical laminated body which is excellent in a thin and lightweight property and durable performance by laminating | stacking a polarizing plate and a liquid crystal cell substrate through an adhesive agent. Another object of the present invention is to provide an advantageous method for producing such an optical laminate.

The present invention relates to an active energy ray curable composition comprising a liquid crystal cell substrate, an epoxy compound having at least one epoxy group in the molecule, and a photocationic polymerization initiator laminated in contact with the surface of the liquid crystal cell substrate. and a thickness of Ru der less 2μm adhesive layer formed from the resin composition are laminated in contact with the surface of the adhesive layer, a polarizing film dichroic dye polyvinyl alcohol resin is adsorbed and oriented A polarizing plate having a thickness of 100 μm or less, the polarizing film laminated in contact with the surface of the adhesive layer, and the opposite side of the polarizing film from the adhesive layer Provided is an optical laminate comprising one transparent protective layer laminated on a surface.

In the optical layered body of the present invention, the active energy ray-curable resin composition constituting the adhesive layer may further contain an oxetane compound. Moreover, the bright protective layer permeable is composed of a cured product of the configuration of a thermoplastic resin film, or an active energy ray curable resin composition, it is preferable that the thickness is 50μm or less.

Furthermore, according to the present invention, the surface of the polarizing film of the polarizing plate having a thickness of 100 μm or less having a polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol-based resin is provided in the molecule. A step of forming an uncured adhesive layer comprising an active energy ray-curable resin composition containing an epoxy-based compound having an epoxy group and a photocationic polymerization initiator; a step of bonding the adhesive layer of uncured were, irradiated with active energy rays, optics and a step thickness to cure the adhesive layer of uncured you form an adhesive layer is 2μm or less, a A method for producing a laminate is also provided.

  According to the present invention, since the thickness can be reduced as compared with a conventional optical laminate in which a polarizing plate is bonded to a liquid crystal cell substrate via an adhesive, the optical laminate, and thus the thin and lightweight liquid crystal panel. In addition, the adhesion between the polarizing plate and the liquid crystal cell substrate is also good. Furthermore, by using an adhesive instead of a pressure-sensitive adhesive for bonding the liquid crystal cell substrate and the polarizing plate, it is possible to provide an optical laminate that can sufficiently withstand heat treatment during device assembly and environmental conditions during device use. . Such an optical laminate of the present invention can be particularly suitably applied to a large-sized liquid crystal display device such as a television.

It is a cross-sectional schematic diagram which shows the basic layer structure of the optical laminated body which concerns on this invention. It is a cross-sectional schematic diagram which shows one form of the layer structure of the optical laminated body which concerns on this invention. It is a cross-sectional view schematically showing a reference embodiment of a layer structure of an optical science laminate.

  As shown in the schematic cross-sectional view of FIG. 1, the optical layered body of the present invention is an adhesive comprising a liquid crystal cell substrate 1 and an active energy ray-curable resin composition laminated in contact with the surface of the liquid crystal cell substrate. A layer 2 and a polarizing plate 5 having a thickness of 100 μm or less having a polarizing film laminated in contact with the surface of the adhesive layer 2 and having a dichroic dye adsorbed and oriented on a polyvinyl alcohol-based resin; In this way, the liquid crystal cell substrate 1 / adhesive layer 2 / polarizing plate 5 is laminated to form the optical laminate 10. Hereinafter, the optical layered body of the present invention and the manufacturing method thereof will be described in detail.

<Liquid crystal cell substrate>
The liquid crystal cell substrate 1 constitutes a liquid crystal cell by sandwiching a liquid crystal with another substrate (not shown), and this liquid crystal cell constitutes a core member of the liquid crystal display device. become. The liquid crystal cell substrate 1 can be composed of glass or a transparent plastic sheet. The glass can be various commonly known glass plates such as soda lime glass, low alkali borosilicate glass, and non-alkali aluminoborosilicate glass, but alkali-free glass is particularly preferably used for the liquid crystal cell. In addition, the transparent plastic sheet may be any known one as long as it is transparent and can be a liquid crystal cell substrate. Specific examples include transparent resins such as polycarbonate, polymethyl methacrylate, polyethylene terephthalate, and epoxy resin. The flexible substrate which consists of can be mentioned.

<Adhesive layer>
In the present invention, the liquid crystal cell substrate 1 and the polarizing plate 5 including a polarizing film are bonded to each other with an active energy ray-curable resin composition containing an epoxy compound having at least one epoxy group in the molecule. Bonding is performed via the agent layer 2, and preferably, the adhesive layer 2 is cured by irradiating the bonded material with active energy rays to obtain an optical laminate 10. By including an epoxy-based compound in the active energy ray-curable resin composition, good adhesion between the polarizing plate 5 and the liquid crystal cell substrate 1 is given, and transparency, mechanical strength, thermal stability, etc. are provided. An excellent adhesive layer having high durability can be obtained. In the present invention, the “epoxy compound having at least one epoxy group in a molecule” has one or more epoxy groups in the molecule, and an active energy ray (for example, ultraviolet ray, visible light, electron beam, A compound that can be cured by irradiation with X-rays or the like. Moreover, the compound which can be hardened | cured by irradiation of an active energy ray including an epoxy-type compound, the oxetane type compound mentioned later, and a (meth) acrylic-type compound may be named generically, and may be called an active energy ray hardening compound.

  As the epoxy compound, it is preferable to use, as a main component, an epoxy compound that does not contain an aromatic ring in the molecule from the viewpoints of weather resistance, refractive index, cationic polymerization, and the like. Examples of the epoxy compound that does not contain an aromatic ring in the molecule include a glycidyl ether of a polyol having an alicyclic ring, an aliphatic epoxy compound, and an alicyclic epoxy compound.

  Explaining the glycidyl ether of a polyol having an alicyclic ring, the polyol having an alicyclic ring is obtained by selectively hydrogenating an aromatic polyol under pressure in the presence of a catalyst. Can be things. Examples of the aromatic polyol include bisphenol type compounds such as bisphenol A, bispheel F, and bisphenol S; novolak type resins such as phenol novolac resin, cresol novolac resin, hydroxybenzaldehyde phenol novolak resin; tetrahydroxydiphenylmethane, tetra Examples thereof include polyfunctional compounds such as hydroxybenzophenone and polyvinylphenol. A glycidyl ether can be obtained by reacting an alicyclic polyol obtained by hydrogenating the aromatic ring of these aromatic polyols with epichlorohydrin. Among the glycidyl ethers of polyols having such alicyclic rings, hydrogenated bisphenol A diglycidyl ether is preferred.

  Examples of the aliphatic epoxy compound include polyglycidyl ethers of aliphatic polyhydric alcohols or alkylene oxide adducts thereof. More specifically, 1,4-butanediol diglycidyl ether; 1,6-hexanediol diglycidyl ether; glycerin triglycidyl ether; trimethylolpropane triglycidyl ether; polyethylene glycol diglycidyl ether; propylene Diglycidyl ether of glycol; Polyglycidyl of polyether polyol obtained by adding one or more alkylene oxides (ethylene oxide or propylene oxide) to aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol or glycerin Examples include ether.

  The alicyclic epoxy compound means an epoxy compound having at least one epoxy group bonded to the alicyclic ring. The “epoxy group bonded to the alicyclic ring” means “—O—” in the following formula, wherein m is an integer of 2 to 5.

Therefore, a compound in which a group in a form in which one or a plurality of hydrogen atoms in (CH ₂ ) _m in the above formula are removed is bonded to another chemical structure can be an alicyclic epoxy compound. One or more hydrogen atoms in (CH ₂ ) _m may be appropriately substituted with a linear alkyl group such as a methyl group or an ethyl group.

  Among the epoxy compounds as described above, an alicyclic epoxy compound, that is, a compound in which at least one of the epoxy groups is bonded to the alicyclic ring is preferable, and in particular, an oxabicyclohexane ring (in the above formula) m = 3) and epoxy compounds having an oxabicycloheptane ring (m = 4 in the above formula) have a high elastic modulus of the cured product and good adhesion between the polarizing plate and the liquid crystal cell substrate. It is more preferably used because it imparts sex. Although the structure of the alicyclic epoxy compound preferably used in the present invention is specifically exemplified below, it is not limited to these compounds.

  (A) Epoxycyclohexylmethyl epoxycyclohexanecarboxylates represented by the following formula (I):

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms.)
(B) Epoxycyclohexanecarboxylates of alkanediol represented by the following formula (II):

(In the formula, R ³ and R ⁴ each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms, and n represents an integer of 2 to 20).
(C) Epoxycyclohexylmethyl esters of dicarboxylic acid represented by the following formula (III):

(In the formula, R ⁵ and R ⁶ each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms, and p represents an integer of 2 to 20).
(D) Epoxycyclohexyl methyl ethers of polyethylene glycol represented by the following formula (IV):

(In the formula, R ⁷ and R ⁸ independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms, and q represents an integer of 2 to 10).
(E) Epoxycyclohexyl methyl ethers of alkanediols represented by the following formula (V):

(In the formula, R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms, and r represents an integer of 2 to 20).
(F) Diepoxy trispiro compound represented by the following formula (VI):

(In the formula, R ¹¹ and R ¹² each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms.)
(G) Diepoxy monospiro compound represented by the following formula (VII):

(In the formula, R ¹³ and R ¹⁴ each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms.)
(H) Vinylcyclohexene diepoxides represented by the following formula (VIII):

(In the formula, R ¹⁵ represents a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms.)
(I) Epoxycyclopentyl ethers represented by the following formula (IX):

(In the formula, R ¹⁶ and R ¹⁷ each independently represent a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms.)
(J) Diepoxytricyclodecanes represented by the following formula (X):

(In the formula, R ¹⁸ represents a hydrogen atom or a linear alkyl group having 1 to 5 carbon atoms.)
Among the alicyclic epoxy compounds exemplified above, the following alicyclic epoxy compounds are commercially available or similar, and are preferably used because they are relatively easy to obtain. It is done.

(A) Esterified product of 7-oxabicyclo [4.1.0] heptane-3-carboxylic acid and (7-oxa-bicyclo [4.1.0] hept-3-yl) methanol [formula (I ) In which R ¹ = R ² = H],
(B) 4-methyl-7-oxabicyclo [4.1.0] heptane-3-carboxylic acid and (4-methyl-7-oxa-bicyclo [4.1.0] hept-3-yl) methanol Esterified product [compound of the above formula (I), R ¹ = 4-CH ₃ , R ² = 4-CH ₃ ],
(C) Esterified product of 7-oxabicyclo [4.1.0] heptane-3-carboxylic acid and 1,2-ethanediol [in the above formula (II), R ³ = R ⁴ = H, n = 2 Compound of
(D) (7-oxabicyclo [4.1.0] hept-3-yl) esterified product of methanol and adipic acid [in the above formula (III), R ⁵ = R ⁶ = H, p = 4 compound ],
(E) (4-Methyl-7-oxabicyclo [4.1.0] hept-3-yl) esterified product of methanol and adipic acid [in the above formula (III), R ⁵ = 4-CH ₃ , R ⁶ = 4-CH ₃ , p = 4 compound]
(F) Etherified product of (7-oxabicyclo [4.1.0] hept-3-yl) methanol and 1,2-ethanediol [in the above formula (V), R ⁹ = R ¹⁰ = H, r = 2 compounds].

  In the present invention, the epoxy compound may be used alone or in combination of two or more.

  Moreover, the active energy ray-curable resin composition may contain an oxetane compound in addition to the epoxy compound. By adding an oxetane compound, the viscosity of the active energy ray-curable resin composition can be lowered and the curing rate can be increased.

  An oxetane compound is a compound having at least one oxetane ring (four-membered ether) in the molecule, such as 3-ethyl-3-hydroxymethyloxetane, 1,4-bis [(3-ethyl-3 -Oxetanyl) methoxymethyl] benzene, 3-ethyl-3- (phenoxymethyl) oxetane, di [(3-ethyl-3-oxetanyl) methyl] ether, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane And phenol novolac oxetane. These oxetane-based compounds can be easily obtained as commercial products. For example, all of these oxetane compounds are trade names such as “Aron Oxetane OXT-101”, “Aron Oxetane OXT-121”, “Aron Oxetane OXT-211”. ”,“ Aron Oxetane OXT-221 ”,“ Aron Oxetane OXT-212 ”(all manufactured by Toagosei Co., Ltd.), and the like. Although the compounding quantity of an oxetane type compound is not specifically limited, Usually, it is 50 weight% or less based on the whole active energy ray-curable compound, Preferably it is 10 to 40 weight%.

  When the active energy ray-curable resin composition used for forming the adhesive layer contains a cationic polymerizable compound such as an epoxy compound or an oxetane compound, the curable resin composition usually contains a photocationic polymerization initiator. Blended. When a cationic photopolymerization initiator is used, it becomes possible to form an adhesive layer at room temperature, so the need to consider the distortion due to heat resistance and expansion of the polarizing film is reduced, and the polarizing plate and the liquid crystal cell substrate can be bonded with good adhesion. Can be pasted. Moreover, since a photocationic polymerization initiator acts catalytically by light, even if this is mixed with a curable resin composition, the curable resin composition is excellent in storage stability and workability.

  The cationic photopolymerization initiator generates a cationic species or a Lewis acid upon irradiation with active energy rays such as visible light, ultraviolet rays, X-rays, and electron beams, and initiates a polymerization reaction of an epoxy compound and / or an oxetane compound. Is. In the present invention, any type of photocationic polymerization initiator may be used. Specific examples include, for example, aromatic diazonium salts; onium salts such as aromatic iodonium salts and aromatic sulfonium salts; iron-allene There are complexes.

  Examples of the aromatic diazonium salt include benzenediazonium hexafluoroantimonate, benzenediazonium hexafluorophosphate, and benzenediazonium hexafluoroborate.

  Examples of the aromatic iodonium salt include diphenyliodonium tetrakis (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, di (4-nonylphenyl) iodonium hexafluorophosphate, and the like.

  Examples of the aromatic sulfonium salt include triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, 4,4′-bis [diphenylsulfonio] diphenyl sulfide bishexa. Fluorophosphate, 4,4′-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenylsulfide bishexafluoroantimonate, 4,4′-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenylsulfide bis Hexafluorophosphate, 7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone hexafluoroantimonate, 7- [di (p-tolui) ) Sulfonio] -2-isopropylthioxanthone tetrakis (pentafluorophenyl) borate, 4-phenylcarbonyl-4′-diphenylsulfonio-diphenyl sulfide hexafluorophosphate, 4- (p-tert-butylphenylcarbonyl) -4′-diphenyl Examples include sulfonio-diphenyl sulfide hexafluoroantimonate, 4- (p-tert-butylphenylcarbonyl) -4′-di (p-toluyl) sulfonio-diphenyl sulfide tetrakis (pentafluorophenyl) borate.

  Examples of the iron-allene complex include xylene-cyclopentadienyl iron (II) hexafluoroantimonate, cumene-cyclopentadienyl iron (II) hexafluorophosphate, xylene-cyclopentadienyl iron (II). -Tris (trifluoromethylsulfonyl) methanide and the like.

  These photocationic polymerization initiators can be easily obtained as commercial products. For example, “Kayarad PCI-220” and “Kayarad PCI-620” (Nippon Kayaku Co., Ltd. )), “UVI-6990” (manufactured by Union Carbide), “Adekaoptomer SP-150”, “Adekaoptomer SP-170” (manufactured by ADEKA, Inc.), “CI-5102”, “ "CIT-1370", "CIT-1682", "CIP-1866S", "CIP-2048S", "CIP-2064S" (Nippon Soda Co., Ltd.), "DPI-101", "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” (manufactured by Midori Chemical Co., Ltd.), “PI-2074” (manufactured by Rhodia), “UVACURE 1590” (manufactured by Daicel Cytec Co., Ltd.), and the like.

  These cationic photopolymerization initiators may be used alone or in combination of two or more. Among these, aromatic sulfonium salts, in particular, have ultraviolet absorption characteristics even in a wavelength region of 300 nm or more, so they have excellent curability, good mechanical strength, and good adhesion to liquid crystal cell substrates and polarizing plates. Since it can give the hardened | cured material which has, it is used preferably.

  The compounding quantity of a photocationic polymerization initiator is 0.5-20 weight part normally with respect to 100 weight part of total amounts of cation polymerizable compounds, such as an epoxy-type compound and an oxetane type compound, Preferably it is 1-6 weight. Part. When the blending amount of the cationic photopolymerization initiator is less than 0.5 parts by weight with respect to 100 parts by weight of the total amount of the cationic polymerizable compound, curing becomes insufficient, and the mechanical strength, polarizing plate and liquid crystal cell substrate There exists a tendency for adhesiveness to fall. On the other hand, when the amount of the cationic photopolymerization initiator exceeds 20 parts by weight with respect to 100 parts by weight of the total amount of the cationic polymerizable compound, the amount of ionic substances in the cured product increases, thereby increasing the hygroscopicity of the cured product. There is a possibility that the durability performance of the obtained optical laminate is lowered.

  The active energy ray-curable resin composition used for forming the adhesive layer contains a radically polymerizable (meth) acrylic compound together with the epoxy compound, or together with the epoxy compound and the oxetane compound. May be. By using a (meth) acrylic compound in combination, it can be expected to increase the hardness and mechanical strength of the adhesive layer, and more easily adjust the viscosity and curing speed of the active energy ray-curable resin composition. Will be able to do it.

  The (meth) acrylic compound is obtained by reacting at least one (meth) acrylate monomer having at least one (meth) acryloyloxy group in the molecule or two or more functional group-containing compounds. Examples include (meth) acryloyloxy group-containing compounds such as (meth) acrylate oligomers having a single (meth) acryloyloxy group. These may be used alone or in combination of two or more. When two or more types are used in combination, two or more types of (meth) acrylate monomers may be used, or two or more types of (meth) acrylate oligomers may be used. Of course, one or more types of (meth) acrylate monomers may be used. And one or more (meth) acrylate oligomers may be used in combination. “(Meth) acrylate” means acrylate or methacrylate.

  The above (meth) acrylate monomer includes a monofunctional (meth) acrylate monomer having one (meth) acryloyloxy group in the molecule, and a bifunctional (meth) methacrylate having two (meth) acryloyloxy groups in the molecule. ) Acrylate monomers and polyfunctional (meth) acrylate monomers having 3 or more (meth) acryloyloxy groups in the molecule.

  Specific examples of monofunctional (meth) acrylate monomers include tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- or 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate 2-hydroxy-3-phenoxypropyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentenyl (meth) acrylate, Benzyl (meth) acrylate, isobornyl (meth) acrylate, phenoxyethyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate Rate, ethyl carbitol (meth) acrylate, trimethylolpropane mono (meth) acrylate, pentaerythritol mono (meth) acrylate, etc. phenoxy polyethylene glycol (meth) acrylate.

  Moreover, a carboxyl group-containing (meth) acrylate monomer may be used as the monofunctional (meth) acrylate monomer. Examples of the carboxyl group-containing monofunctional (meth) acrylate monomer include 2- (meth) acryloyloxyethyl phthalic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, carboxyethyl (meth) acrylate, and 2- (meth). Examples include acryloyloxyethyl succinic acid, N- (meth) acryloyloxy-N ′, N′-dicarboxymethyl-p-phenylenediamine, and 4- (meth) acryloyloxyethyl trimellitic acid.

  Bifunctional (meth) acrylate monomers include alkylene glycol di (meth) acrylates, polyoxyalkylene glycol di (meth) acrylates, halogen-substituted alkylene glycol di (meth) acrylates, aliphatic polyol di (meth) acrylates Di (meth) acrylates of hydrogenated dicyclopentadiene or tricyclodecane dialkanol, di (meth) acrylates of dioxane glycol or dioxane dialkanol, di (meth) of alkylene oxide adducts of bisphenol A or bisphenol F Representative examples include acrylates and epoxy di (meth) acrylates of bisphenol A or bisphenol F, but are not limited to these, and various types can be used.

  More specific examples of the bifunctional (meth) acrylate monomer include ethylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1 , 6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol di (meth) acrylate, ditri Methylolpropane di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polyethylene Glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polytetramethylene glycol di (meth) acrylate, silicone di (meth) acrylate, di (meth) acrylate of hydroxypivalic acid neopentyl glycol ester, 2,2 -Bis [4- (meth) acryloyloxyethoxyethoxyphenyl] propane, 2,2-bis [4- (meth) acryloyloxyethoxyethoxycyclohexyl] propane, hydrogenated dicyclopentadienyl di (meth) acrylate, tricyclo Decanedimethanol di (meth) acrylate, 1,3-dioxane-2,5-diyldi (meth) acrylate [also known as dioxane glycol di (meth) acrylate], hydroxypivalaldehyde and trimethylo Acetal compound with propane [chemical name: 2- (2-hydroxy-1,1-dimethylethyl) -5-ethyl-5-hydroxymethyl-1,3-dioxane], di (meth) acrylate, tris (hydroxyethyl) ) Isocyanurate di (meth) acrylate.

  The trifunctional or higher polyfunctional (meth) acrylate monomers include glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol. Of tri- or higher functional aliphatic polyols such as tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. Poly (meth) acrylate is a representative one. Besides, poly (meth) acrylate of tri- or higher functional halogen-substituted polyol, alkylene oxide of glycerin Tri (meth) acrylate of adduct, tri (meth) acrylate of alkylene oxide adduct of trimethylolpropane, 1,1,1-tris [(meth) acryloyloxyethoxyethoxy] propane, tris (hydroxyethyl) isocyanurate tri Examples include (meth) acrylates.

  On the other hand, (meth) acrylate oligomers include urethane (meth) acrylate oligomers, polyester (meth) acrylate oligomers, and epoxy (meth) acrylate oligomers.

  The urethane (meth) acrylate oligomer is a compound having a urethane bond (—NHCOO—) and at least two (meth) acryloyloxy groups in the molecule. Specifically, a urethanization reaction product of a hydroxyl group-containing (meth) acrylate monomer and a polyisocyanate each having at least one (meth) acryloyloxy group and at least one hydroxyl group in the molecule, and a polyol Urethane reaction product of terminal isocyanate group-containing urethane compound obtained by reaction with isocyanate, and (meth) acrylate monomer each having at least one (meth) acryloyloxy group and at least one hydroxyl group in the molecule, etc. It can be.

  Examples of the hydroxyl group-containing (meth) acrylate monomer used in the urethanization reaction include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 2-hydroxy-3- Examples include phenoxypropyl (meth) acrylate, glycerin di (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth) acrylate.

  Examples of the polyisocyanate used for the urethanization reaction with the hydroxyl group-containing (meth) acrylate monomer include hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, and aromatics among these diisocyanates. Diisocyanates obtained by hydrogenating isocyanates (eg, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, etc.), di- or tri-isocyanates such as triphenylmethane triisocyanate, dibenzylbenzene triisocyanate, and Examples thereof include polyisocyanates obtained by multiplying the above diisocyanates.

  In addition, as polyols used to obtain terminal isocyanate group-containing urethane compounds by reaction with polyisocyanates, polyester polyols, polyether polyols, etc., as well as aromatic, aliphatic and alicyclic polyols should be used. Can do. Aliphatic and alicyclic polyols include 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, trimethylol ethane, trimethylol propane, ditriol. Examples include methylolpropane, pentaerythritol, dipentaerythritol, dimethylolheptane, dimethylolpropionic acid, dimethylolbutanoic acid, glycerin, and hydrogenated bisphenol A.

  The polyester polyol is obtained by a dehydration condensation reaction between the above polyols and a polybasic carboxylic acid or an anhydride thereof. Polybasic carboxylic acids or their anhydrides include (anhydrous) succinic acid, adipic acid, (anhydrous) maleic acid, (anhydrous) itaconic acid, (anhydrous) trimellitic acid, (anhydrous) pyromellitic acid, (anhydrous) Examples include phthalic acid, isophthalic acid, terephthalic acid, hexahydro (anhydride) phthalic acid, and the like.

  The polyether polyol may be a polyoxyalkylene-modified polyol obtained by a reaction of the above-described polyols or dihydroxybenzenes with an alkylene oxide, in addition to the polyalkylene glycol.

  The polyester (meth) acrylate oligomer is a compound having an ester bond and at least two (meth) acryloyloxy groups in the molecule. Specifically, it can be obtained by dehydration condensation reaction of (meth) acrylic acid, polybasic carboxylic acid or anhydride thereof, and polyol. Polybasic carboxylic acids or anhydrides used in the dehydration condensation reaction include (anhydrous) succinic acid, adipic acid, (anhydrous) maleic acid, (anhydrous) itaconic acid, (anhydrous) trimellitic acid, (anhydrous) pyrone Examples include merit acid, hexahydro (anhydride) phthalic acid, (anhydrous) phthalic acid, isophthalic acid, and terephthalic acid. Examples of the polyol used for the dehydration condensation reaction include 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, trimethylolethane, trimethylolpropane, Examples include ditrimethylolpropane, pentaerythritol, dipentaerythritol, dimethylolheptane, dimethylolpropionic acid, dimethylolbutanoic acid, glycerin, and hydrogenated bisphenol A.

  The epoxy (meth) acrylate oligomer can be obtained by addition reaction of polyglycidyl ether and (meth) acrylic acid, and has at least two (meth) acryloyloxy groups in the molecule. Examples of the polyglycidyl ether used for the addition reaction include ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, and bisphenol A diglycidyl ether.

  When the (meth) acrylic compound is added to the active energy ray-curable resin composition used for forming the adhesive layer 2, the amount is 20% by weight or less based on the total amount of the active energy ray-curable compound. Furthermore, it is preferable to set it to 10 weight% or less. When the compounding amount of the (meth) acrylic compound increases, the adhesion between the polarizing plate and the liquid crystal cell substrate tends to decrease.

  When the active energy ray-curable resin composition contains a radical polymerizable compound such as the (meth) acrylic compound as described above, a photo radical polymerization initiator is preferably blended. Any radical photopolymerization initiator may be used as long as it can initiate polymerization of a radical polymerizable compound such as a (meth) acrylic compound by irradiation with active energy rays, and a conventionally known one can be used. Specific examples of the photoradical polymerization initiator include acetophenone, 3-methylacetophenone, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-methyl-1 -[4- (methylthio) phenyl-2-morpholinopropan-1-one, acetophenone-based initiators such as 2-hydroxy-2-methyl-1-phenylpropan-1-one; benzophenone, 4-chlorobenzophenone, 4, Benzophenone initiators such as 4'-diaminobenzophenone; Benzoin ether initiators such as benzoinpropyl ether and benzoin ethyl ether; Thioxanthone initiators such as 4-isopropylthioxanthone; Others, xanthone, fluorenone, camphorquinone, benzaldehyde Anthraquinone, and the like.

  The compounding quantity of radical photopolymerization initiator is 0.5-20 weight part normally with respect to 100 weight part of radically polymerizable compounds, such as a (meth) acrylic-type compound, Preferably it is 1-6 weight part. When the amount of radical photopolymerization initiator is less than 0.5 parts by weight based on 100 parts by weight of the radical polymerizable compound, curing becomes insufficient, and mechanical strength and adhesion between the polarizing plate and the liquid crystal cell substrate are lowered. Tend to. Further, when the amount of the photo radical polymerization initiator exceeds 20 parts by weight with respect to 100 parts by weight of the radical polymerizable compound, the active energy ray-curable compound (cationic polymerizable compound including an epoxy compound) in the curable resin composition is used. The amount of the curable compound and the radical polymerizable compound such as a (meth) acrylic compound) is relatively small, and the durability performance of the obtained optical laminate may be deteriorated.

  The active energy ray-curable resin composition can further contain a photosensitizer as necessary. By incorporating a photosensitizer, the reactivity of cationic polymerization and / or radical polymerization is improved, and the mechanical strength of the adhesive layer and the adhesion between the polarizing plate and the liquid crystal cell substrate can be improved. . Examples of the photosensitizer include carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo and diazo compounds, halogen compounds, and photoreducible dyes. More specific examples of the photosensitizer include, for example, benzoin derivatives such as benzoin methyl ether, benzoin isopropyl ether, α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, o-benzoyl Benzophenone derivatives such as methyl benzoate, 4,4′-bis (dimethylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-isopropylthioxanthone; 2-chloroanthraquinone, Anthraquinone derivatives such as 2-methylanthraquinone; Acridone derivatives such as N-methylacridone and N-butylacridone; Others, α, α-diethoxyacetophenone, benzyl, fluorenone, xanthone, urine Although a ranyl compound, a halogen compound, etc. are mentioned, it is not limited to these. These photosensitizers may be used alone or in combination of two or more. The photosensitizer is preferably contained in the range of 0.1 to 20 parts by weight based on 100 parts by weight of the entire active energy ray-curable compound.

  Moreover, the active energy ray-curable resin composition may contain an antistatic agent for imparting antistatic performance to the optical laminate. The antistatic agent is not particularly limited, and a known antistatic agent can be used. For example, cationic surfactants such as acyloylamidopropyldimethylhydroxyethylammonium nitrate, acyloylamidopropyltrimethylammonium sulfate, cetylmorpholium methosulfate; linear alkyl phosphate potassium salt, polyoxyethylene alkyl phosphate Anionic surfactants such as potassium salts and alkane sulfonates; nonionic surfactants such as N, N-bis (hydroxyethyl) -N-alkylamines and their fatty acid ester derivatives and polyhydric alcohol fatty acid partial esters An agent or the like can be used. The blending ratio of these antistatic agents is appropriately determined according to the desired characteristics, but is usually about 0.1 to 10 parts by weight with 100 parts by weight of the entire active energy ray-curable compound.

  To the active energy ray-curable resin composition, a known polymer additive usually used for polymers can be added. Examples include primary antioxidants such as phenols and amines, sulfur secondary antioxidants, hindered amine light stabilizers (HALS), benzophenone, benzotriazole, and benzoate UV absorbers. .

  Furthermore, the active energy ray-curable resin composition may contain a solvent as necessary. The solvent is appropriately selected in consideration of the solubility of the components constituting the active energy ray-curable resin composition. Commonly used solvents include: aliphatic hydrocarbons such as n-hexane and cyclohexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, propanol, isopropanol and n-butanol; acetone and methyl ethyl ketone Ketones such as methyl isobutyl ketone and cyclohexanone; esters such as methyl acetate, ethyl acetate and butyl acetate; cellosolves such as methyl cellosolve, ethyl cellosolve and butyl cellosolve; halogenated hydrocarbons such as methylene chloride and chloroform It is done. The mixing ratio of the solvent is appropriately determined from the viewpoint of adjusting the viscosity depending on the processing purpose such as film formability.

It is preferable that the adhesive layer 2 is thin because there is little risk of impairing the appearance of the polarizing plate. When the thickness increases , the adhesive force between the polarizing plate and the liquid crystal cell substrate may not be sufficient due to insufficient curing of the adhesive.

<Polarizer>
As described above with reference to FIG. 1, the optical layered body of the present invention includes the polarizing plate 5 stacked on the liquid crystal cell substrate 1 via the adhesive layer 2 described above. The polarizing plate 5 has at least a polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin. The polarizing plate 5 has a thickness of 100 μm or less from the viewpoint of reducing the thickness of the optical laminate 10 and the liquid crystal panel . Brittle in the polarizing film alone, the surface to be stuck to the liquid crystal cell substrate 1 on the opposite side, Keru set the transparent protective layer.

  FIG. 2 is a schematic cross-sectional view showing one embodiment of the layer configuration of the optical laminate according to the present invention. In this embodiment, a transparent protective layer 7 is provided on one surface of the polarizing film 6 to form a polarizing plate 5, and the surface of the polarizing film 6 opposite to the surface on which the transparent protective layer 7 is provided directly through the adhesive layer 2. The optical laminate 11 is configured by being bonded to the liquid crystal cell substrate 1. That is, in the optical laminate 11, the polarizing film 6 is laminated in contact with the surface of the adhesive layer 2, and the transparent protective layer 7 is laminated on the surface of the polarizing film 6 opposite to the adhesive layer 2. .

Figure 3 is a cross-sectional view schematically showing a reference embodiment of a layer structure of an optical science laminate. In this embodiment, the transparent protective layer 7 is provided on one side of the polarizing film 6, and an appropriate resin layer 8 is provided on the other side of the polarizing film 6 to form the polarizing plate 5, and the resin layer 8 side is interposed through the adhesive layer 2. The optical laminate 12 is configured by being bonded to the liquid crystal cell substrate 1. The resin layer 8 can be a transparent protective layer similar to or different from the transparent protective layer 7 provided on the opposite side of the polarizing film 6, and may be an optical functional layer. As an example of the optical functional layer, there is a retardation plate used for the purpose of compensation of retardation by a liquid crystal cell. Examples of retardation plates include birefringent films composed of stretched films of various plastics, films in which discotic liquid crystals and nematic liquid crystals are oriented and fixed, and retardation development of the above liquid crystals and inorganic layered compounds on a film substrate. For example, a coating film containing a substance is formed and the orientation is fixed. In this case, a cellulose-based film such as triacetyl cellulose is preferably used as a film substrate that supports a coating film containing a retardation-expressing substance.

  As described above, the polarizing plate 5 includes the polarizing film 6 and may have any layer as long as the thickness is 100 μm or less, but the layers other than the polarizing film 6 are two layers or less, particularly One or two layers are preferable from the viewpoint of thinning the optical laminate or the liquid crystal panel while protecting the polarizing film 6. From such a viewpoint, as shown in FIG. 2, the polarizing film 6 has a transparent protective layer 7 on one surface, and the surface of the polyvinyl alcohol-based resin film (polarizing film surface) opposite to the transparent protective layer 7. The form of being directly bonded to the liquid crystal cell substrate 1 via the adhesive layer 2 is a preferable one.

(Polarizing film)
The polarizing film 6 constituting the polarizing plate 5 is obtained by adsorbing and orienting a dichroic dye on a polyvinyl alcohol resin. More specifically, a film obtained by adsorbing and orienting a dichroic dye on a uniaxially stretched polyvinyl alcohol resin film is preferably used.

  The polyvinyl alcohol resin constituting the polarizing film can be obtained by saponifying a polyvinyl acetate resin. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, unsaturated sulfonic acids, olefins, and vinyl ethers. The saponification degree of the polyvinyl alcohol-based resin is usually about 85 to 100 mol%, preferably 98 to 100 mol%. The polyvinyl alcohol-based resin may be further modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol resin is usually about 1,000 to 10,000, preferably about 1,500 to 10,000.

  A film obtained by forming such a polyvinyl alcohol resin is used as a raw film of a polarizing film. The method for forming a polyvinyl alcohol-based resin is not particularly limited, and can be formed by a known method. Although the film thickness of a polyvinyl alcohol-type raw film is not specifically limited, For example, it is about 10 micrometers-150 micrometers.

  A polarizing film is usually a process of uniaxially stretching a raw film made of a polyvinyl alcohol resin as described above, a process of dyeing a polyvinyl alcohol resin film with a dichroic dye and adsorbing the dichroic dye, two colors It is manufactured through a step of treating a polyvinyl alcohol-based resin film adsorbed with a functional dye with an aqueous boric acid solution and a step of washing with water after the treatment with an aqueous boric acid solution.

  Uniaxial stretching may be performed before dyeing with a dichroic dye, may be performed simultaneously with dyeing, or may be performed after dyeing. When uniaxial stretching is performed after dyeing with a dichroic dye, the uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. Moreover, it is also possible to perform uniaxial stretching in these several steps. In uniaxial stretching, it may be uniaxially stretched between rolls having different peripheral speeds, or may be uniaxially stretched using a hot roll. Further, it may be dry stretching such as stretching in the air, or may be wet stretching in which stretching is performed in a state swollen with a solvent. The draw ratio is usually about 4 to 8 times.

  The polyvinyl alcohol resin film is dyed with a dichroic dye, for example, by immersing the polyvinyl alcohol resin film in an aqueous solution containing the dichroic dye. As the dichroic dye, iodine, a dichroic organic dye, or the like is used. In addition, it is preferable that the polyvinyl alcohol-type resin film performs the immersion process to water before a dyeing process.

  When iodine is used as the dichroic dye, a method of immersing a polyvinyl alcohol-based resin film in an aqueous solution containing iodine and potassium iodide is usually employed as a dyeing method. The content of iodine in this aqueous solution is usually about 0.01 to 0.5 parts by weight with respect to 100 parts by weight of water, and the content of potassium iodide is usually 0.00 with respect to 100 parts by weight of water. About 5 to 10 parts by weight. The temperature of the aqueous solution used for dyeing is usually about 20 to 40 ° C., and the immersion time (dyeing time) in this aqueous solution is usually about 30 to 300 seconds.

On the other hand, when a dichroic organic dye is used as the dichroic dye, a method of immersing a polyvinyl alcohol-based resin film in a dye aqueous solution containing a water-soluble dichroic dye is usually employed as a dyeing method. . The content of the dichroic dye in this dye aqueous solution is usually about 1 × 10 ⁻³ to 1 × 10 ⁻² parts by weight with respect to 100 parts by weight of water. The dye aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing assistant. The temperature of the aqueous dye solution is usually about 20 to 80 ° C., and the immersion time (dyeing time) in the aqueous dye solution is usually about 30 to 300 seconds.

  The boric acid treatment after dyeing with a dichroic dye is performed by immersing the dyed polyvinyl alcohol-based resin film in a boric acid-containing aqueous solution. The boric acid content in the boric acid-containing aqueous solution is usually about 2 to 15 parts by weight, preferably about 5 to 12 parts by weight with respect to 100 parts by weight of water. When iodine is used as the dichroic dye, the boric acid-containing aqueous solution preferably contains potassium iodide. The content of potassium iodide in the boric acid-containing aqueous solution is usually about 2 to 20 parts by weight, preferably about 5 to 15 parts by weight with respect to 100 parts by weight of water. The immersion time in the boric acid-containing aqueous solution is usually about 100 to 1,200 seconds, preferably about 150 to 600 seconds, and more preferably about 200 to 400 seconds. The temperature of the boric acid-containing aqueous solution is usually 50 ° C or higher, preferably 50 to 85 ° C.

  The polyvinyl alcohol resin film after the boric acid treatment is usually washed with water. The water washing treatment is performed, for example, by immersing a boric acid-treated polyvinyl alcohol resin film in water. The temperature of water in the water washing treatment is usually about 5 to 40 ° C., and the immersion time is about 2 to 120 seconds. After washing with water, a drying process is performed to obtain a polarizing film. The drying treatment can be performed using a hot air dryer or a far infrared heater. A drying temperature is about 40-100 degreeC normally. The time for the drying treatment is usually about 120 to 600 seconds.

  As described above, a polarizing film in which a dichroic dye is adsorbed and oriented on a uniaxially stretched polyvinyl alcohol resin film can be produced. The thickness of the polarizing film can be about 5 to 40 μm.

(Transparent protective layer)
Transparent protective layer 7 provided on one surface of the polarizing film 6, such as cellulose acetate-based resin, cycloolefin resin, polyolefin resin, acrylic resin, polyimide resin, polycarbonate resin, a polyester resin, in the art It can be comprised with the appropriate thermoplastic resin film conventionally used widely as a formation material of a protective layer. Moreover, the transparent protective layer 7 can also be comprised with the hardened | cured material of an active energy ray curable resin composition. Among these, from the viewpoint of mass productivity and adhesiveness, it is preferable to use, as the transparent protective layer 7, a film made of a cellulose acetate-based resin or a cycloolefin-based resin, or a cured product of an active energy ray-curable resin composition. When the transparent protective layer 7 is made of a thermoplastic resin film, the thickness is usually about 10 to 50 μm. On the other hand, when the transparent protective layer 7 is composed of a cured product of the active energy ray-curable resin composition, the thickness can be 10 μm or less, for example, about 1 to 10 μm.

  The cellulose acetate-based resin film used as the transparent protective layer 7 is a film made of a cellulose portion or a complete acetate ester, and examples thereof include a triacetyl cellulose film and a diacetyl cellulose film.

  Such a cellulose acetate-based resin film is an appropriate commercial product such as “Fujitac TD80”, “Fujitac TD80UF” and “Fujitac TD80UZ” (manufactured by Fujifilm Corporation), “KC8UX2M” and “KC8UY” ( As described above, Konica Minolta Opto Co., Ltd. (all are trade names) and the like can be suitably used.

  The cycloolefin resin suitably used for the transparent protective layer 7 is, for example, a thermoplastic resin having a monomer unit composed of a cyclic olefin (cycloolefin) such as norbornene or a polycyclic norbornene monomer (thermoplastic). Also called cycloolefin resin. This cycloolefin-based resin may be a hydrogenated product of the above-mentioned cycloolefin ring-opening polymer, a hydrogenated product of a ring-opening copolymer using two or more kinds of cycloolefins, and a cycloolefin and a chain olefin. And / or an addition polymer with an aromatic compound having a vinyl group or the like. Those having a polar group introduced are also effective.

  When a transparent protective layer is formed using a copolymer of a cycloolefin and a chain olefin and / or an aromatic compound having a vinyl group, examples of the chain olefin include ethylene, propylene, and the like. Examples of the aromatic compound include styrene, α-methylstyrene, and nuclear alkyl-substituted styrene. In such a copolymer, the monomer unit composed of cycloolefin may be 50 mol% or less (preferably 15 to 50 mol%). In particular, when a transparent protective layer is formed using a terpolymer of cycloolefin, chain olefin, and aromatic compound having a vinyl group, the number of monomer units composed of cycloolefin is relatively small as described above. It can be an amount. In such a terpolymer, the monomer unit composed of a chain olefin is usually 5 to 80 mol%, and the monomer unit composed of an aromatic compound having a vinyl group is usually 5 to 80 mol%.

  Cycloolefin-based resins are commercially available as appropriate, for example, “Topas” (available from TOPAS ADVANCED POLYMERS GmbH, available from Polyplastics), “Arton” (manufactured by JSR), “ZEONOR”. ”(Made by Nippon Zeon Co., Ltd.),“ ZEONEX ”(made by Nippon Zeon Co., Ltd.),“ Apel ”(manufactured by Mitsui Chemicals, Inc.) (all are trade names), etc. can be suitably used. . When such a cycloolefin-based resin is formed into a film, a known method such as a solvent casting method or a melt extrusion method is appropriately used. Also, for example, “Essina” (manufactured by Sekisui Chemical Co., Ltd.), “SCA40” (manufactured by Sekisui Chemical Co., Ltd.), “ZEONOR FILM” (manufactured by Nippon Zeon Co., Ltd.), “ARTON FILM” (JSR Corporation) A commercially available product of a film made of a cycloolefin resin formed in advance such as)) may be used as the transparent protective layer.

  The cycloolefin resin film used as the transparent protective layer may be uniaxially stretched or biaxially stretched. In this case, the draw ratio is usually 1.1 to 5 times, preferably 1.1 to 3 times.

  Examples of the active energy ray-curable resin composition that can be used for the transparent protective layer 7 include the same active energy ray-curable resin compositions that form the adhesive layer 2 described above. Active energy ray-curable resin composition for forming transparent protective layer and active energy ray-curable compound contained therein, active energy ray-curable resin composition as adhesive composition, and active energy ray contained therein The curable compound or the like may be the same or different.

  Specifically, the active energy ray-curable resin composition used for the transparent protective layer 7 contains an epoxy compound, like the active energy ray-curable resin composition used for forming the adhesive layer 2 described above. It is also effective to add an oxetane compound. Thus, since it contains an epoxy compound and optionally further contains an oxetane compound, a photocationic polymerization initiator is also usually blended. About these epoxy compounds, oxetane compounds and photocationic polymerization initiators, the same explanation as that for the adhesive layer 2 is applied.

  In particular, the active energy ray-curable resin composition used for the transparent protective layer 7 includes a radically polymerizable compound, specifically, as described above (meta-methacrylate) in addition to the epoxy compound and the optional oxetane compound. ) It is effective to contain an acrylic compound. By using a (meth) acrylic compound in combination, a transparent protective layer having high hardness, excellent mechanical strength, and superior durability can be obtained. Furthermore, adjustments such as the viscosity and curing speed of the active energy ray-curable resin composition can be performed more easily. In the active energy ray-curable resin composition for the transparent protective layer 7, the (meth) acrylic compound can be added up to about 70% by weight based on the total amount of the active energy ray-curable compound. The blending amount of the (meth) acrylic compound is more preferably 35 to 70% by weight, especially 40 to 60% by weight. When the compounding amount of the (meth) acrylic compound exceeds 70% by weight, the adhesion with the polarizing film tends to be lowered.

  When blending such a (meth) acrylic compound, a radical photopolymerization initiator as described above is also blended. About the compounding quantity of radical photopolymerization initiator, the description similar to having done about the adhesive bond layer 2 applies previously. The active energy ray-curable resin composition used for the transparent protective layer 7 can also contain other various components similar to those described above for the adhesive layer 2.

  The transparent protective layer 7 of the polarizing plate has a surface opposite to the surface to be attached to the polarizing film and subjected to surface treatment such as antiglare treatment, hard coat treatment, antistatic treatment, and antireflection treatment. Also good. Moreover, the coating layer which consists of a liquid crystalline compound, its high molecular weight compound, etc. may be formed in the surface on the opposite side to the surface stuck to the polarizing film of a transparent protective layer.

  When the transparent protective layer 7 is a resin film, an adhesive (adhesive composition) is used for attaching the polarizing film 6 and the transparent protective layer 7. The adhesive composition used for this purpose is not particularly limited, and examples thereof include a curable resin composition containing an active energy ray-curable compound and an aqueous adhesive in which an adhesive component is dissolved or dispersed in water. In this, since a drying process is unnecessary, it is preferable to use the curable resin composition containing an active energy ray curable compound. When using a curable resin composition as an adhesive composition, after normally bonding the polarizing film 6 and the transparent protective layer 7 through a curable resin composition layer, it is active energy ray to this bonding material. To cure the curable resin composition layer.

  As the curable resin composition that can be the adhesive composition, the same active energy ray-curable resin composition used for adhesion between the liquid crystal cell substrate 1 and the polarizing plate 5 described above can be used. The active energy ray-curable resin composition used for adhesion between the liquid crystal cell substrate 1 and the polarizing plate 5 and the active energy ray-curable compound contained therein, and the curability used for adhesion between the transparent protective layer 7 and the polarizing film 6. The resin composition and the active energy ray-curable compound contained therein may be the same or different.

  Examples of the water-based adhesive in which the adhesive component is dissolved or dispersed in water include an adhesive composition mainly composed of a polyvinyl alcohol resin or a urethane resin.

  When using a polyvinyl alcohol-based resin as the main component of the water-based adhesive, the polyvinyl alcohol-based resin is not only partially saponified polyvinyl alcohol or fully saponified polyvinyl alcohol, but also carboxyl group-modified polyvinyl alcohol, acetoacetyl group-modified polyvinyl alcohol, It may be a modified polyvinyl alcohol resin such as methylol group-modified polyvinyl alcohol or amino group-modified polyvinyl alcohol. When a polyvinyl alcohol resin is used as the adhesive component, the adhesive is often prepared as an aqueous solution of a polyvinyl alcohol resin. The density | concentration of the polyvinyl alcohol-type resin in an adhesive agent is about 1-10 weight part normally with respect to 100 weight part of water, Preferably it is 1-5 weight part.

  In order to improve the adhesiveness, it is preferable to add a curable component such as glyoxal or a water-soluble epoxy resin or a crosslinking agent to the adhesive containing a polyvinyl alcohol resin as a main component. Examples of water-soluble epoxy resins include polyamide polyamine epoxy resins obtained by reacting epichlorohydrin with polyamide polyamines obtained by reaction of polyalkylene polyamines such as diethylenetriamine and triethylenetetramine with dicarboxylic acids such as adipic acid. Can be mentioned. Commercially available products of such polyamide polyamine epoxy resins include “Smiles Resin 650” and “Smiles Resin 675” sold by Sumika Chemtex Co., Ltd., and “WS-525” sold by Japan PMC Co., Ltd. Etc., and these can be preferably used. The addition amount of these curable components or crosslinking agents is usually 1 to 100 parts by weight, preferably 1 to 50 parts by weight with respect to 100 parts by weight of the polyvinyl alcohol resin. If the amount added is small, the effect of improving the adhesiveness is reduced, while if the amount added is large, the adhesive layer tends to be brittle.

  When a urethane resin is used as the main component of the water-based adhesive, examples of a suitable adhesive composition include a mixture of a polyester ionomer-type urethane resin and a compound having a glycidyloxy group. The polyester-based ionomer-type urethane resin here is a urethane resin having a polyester skeleton, and a small amount of an ionic component (hydrophilic component) is introduced therein. Such an ionomer-type urethane resin is suitable as a water-based adhesive because it is emulsified directly in water without using an emulsifier to form an emulsion. Polyester ionomer urethane resins are known per se. For example, Japanese Patent Application Laid-Open No. 7-97504 discloses a polyester ionomer type urethane resin as an example of a polymer dispersant for dispersing a phenolic resin in an aqueous medium. JP-A-2005-181817 discloses a mode in which a cycloolefin resin film is bonded to a polarizing film made of a polyvinyl alcohol resin by using a mixture of a polyester ionomer type urethane resin and a compound having a glycidyloxy group as an adhesive. It is shown.

<Method for producing optical laminate>
The manufacturing method of the optical laminated body which concerns on this invention is used suitably as a method for manufacturing the above-mentioned optical laminated body of this invention, (1) Adhesive layer formation process shown below, ( 2) obtain Bei the bonding step, and (3) curing step.

(1) At least one in the molecule on the surface of the polarizing film (polarizing plate 5) having a polarizing film (polarizing plate 5) having a polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin. An adhesive layer forming step of forming an adhesive layer (adhesive layer 2) comprising an active energy ray-curable resin composition containing an epoxy-based compound having an epoxy group and a cationic photopolymerization initiator in an uncured state ;
(2) A bonding step of bonding the adhesive layer 2 formed on the polarizing film surface of the polarizing plate 5 in the adhesive layer forming step to the liquid crystal cell substrate (liquid crystal cell substrate 1),
(3) Adhering to the laminate comprising the liquid crystal cell substrate 1 / adhesive layer 2 / polarizing plate 5 obtained in the above-mentioned bonding step by irradiating active energy rays such as visible light, ultraviolet rays, X-rays and electron beams. the adhesive layer 2 is cured, resulting Ru curing process of the adhesive layer thickness after curing is 2μm or less.

  In this manufacturing method, the polarizing plate may be a polarizing film alone, or may be one in which other layers are laminated in advance as described above. When forming a transparent protective layer made of a cured product of an active energy ray curable resin composition on one side of a polarizing film, or when laminating a film via an adhesive made of an active energy ray curable resin composition, the above In the curing step, it is possible to cure the transparent protective layer or the adhesive for bonding the polarizing film and the transparent protective layer simultaneously with the curing of the adhesive layer 2. Hereinafter, each step will be specifically described.

First, in the adhesive layer forming step (1), the polarizing film surface of the polarizing plate 5, to form an adhesive layer 2 composed of an active energy ray curable resin composition, directly to the polarizing film surface of the polarizing plate 5 The active energy ray-curable resin composition is applied to a base film made of a transparent resin such as polyethylene terephthalate or a method of coating the active energy ray-curable resin composition described above and drying it as necessary. A method of transferring the coating layer of the active energy ray-curable resin composition to the polarizing film of the polarizing plate 5 and the like can be employed. When employ | adopting the latter method, a base film is removed after that and it uses for the following bonding process. Examples of the base film include a polyethylene terephthalate film, a polycarbonate film, a triacetyl cellulose film, a norbornene film, a polyester film, and a polystyrene film. The surface on which the active energy ray-curable resin composition of the base film is coated may be subjected to a peeling treatment.

  Here, as shown in FIG. 2, for example, when a transparent protective layer 7 is provided on the surface of the polarizing film 6 opposite to the liquid crystal cell substrate 1 side, the transparent protective layer 7 is cured with active energy rays. In the case of a cured product of the curable resin composition, a layer of the active energy ray-curable resin composition corresponding to the transparent protective layer 7 is also provided on the surface of the polarizing film 6. When the layer of the active energy ray-curable resin composition for the transparent protective layer 7 is formed on another base film and bonded to the polarizing film 6, the base film remains as it is until the subsequent curing step. And preferably after the curing step is finished.

Then, in the bonding step (2), the adhesive layer 2 provided on the polarizing plate 5 is bonded to the liquid crystal cell substrate 1. Then, the irradiation in the hardening step (3), the bonding material which are laminated in this order on the liquid crystal cell substrate 1 / adhesive layer 2 / the polarizing plate 5, visible rays, ultraviolet rays, X-rays, an active energy ray such as electron beam By doing so, the adhesive layer 2 is cured to obtain an optical laminate. At this time, when the active energy ray-curable resin composition layer for forming the transparent protective layer 7 is provided on the surface of the polarizing film 6 opposite to the liquid crystal cell substrate 1 side, the transparent protective layer 7 It is preferable to cure the active energy ray-curable resin composition for the same. When the base film is provided on the transparent protective layer 7, finally, the base film is peeled and removed.

On the other hand, for example, in the case of using a polarizing plate 5 having a transparent protective layer 7 made of a resin film on one surface of the polarizing film 6, a transparent protective layer 7 and the polarizing film 6 from the active energy ray curable resin composition In the case of bonding with an adhesive, the active energy ray-curable resin composition is applied to the bonding surface of the transparent protective layer 7 and / or the polarizing film 6 and the active energy ray-curable resin composition layer is interposed therebetween. After laminating the polarizing film 6 and the transparent protective layer 7 (resin film), the others are the same as above, and after obtaining the bonded product laminated in the order of the liquid crystal cell substrate 1 / adhesive layer 2 / polarizing plate 5 What is necessary is just to irradiate an active energy ray to this bonding thing by the method similar to the above.

  The adhesive layer 2 for adhering the liquid crystal cell substrate 1 and the polarizing plate 5 is not formed on the surface of the polarizing plate 5, but on the bonding surface of the liquid crystal cell substrate 1 with the polarizing plate. By applying the active energy ray-curable resin composition to be the layer 2 by a spin coat method or the like, overlaying the polarizing plate 5 thereon, irradiating the active energy ray, and curing the active energy ray-curable resin composition. An optical laminate can also be manufactured. However, considering the ease of production, the adhesive layer 2 made of the active energy ray-curable resin composition described above is formed on one side of the polarizing plate 5, and the adhesive layer 2 is bonded to the liquid crystal cell substrate 1. Thereafter, the method of curing the adhesive layer 2 is advantageous.

  The means for applying the active energy ray-curable resin composition for forming the adhesive layer or the transparent protective layer to the polarizing plate, the polarizing film, or the base film is not particularly limited. For example, a doctor blade, a wire bar, a die coating Various coating methods such as coating, comma coating, and gravure coating can be used. Moreover, since each coating system has an optimum viscosity range, it is also a useful technique to adjust the viscosity using a solvent. Examples of the solvent for this purpose include those described above.

The light source used for the irradiation of the active energy ray is not particularly limited, but has a light emission distribution at a wavelength of 400 nm or less, for example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a chemical lamp, a black light lamp, microwave excitation A mercury lamp, a metal halide lamp, etc. can be used. The light irradiation intensity to the active energy ray-curable resin composition varies depending on the composition, but the irradiation intensity in the wavelength region effective for activating the photocationic polymerization initiator and / or the photoradical polymerization initiator is 10 to 2500 mW. / Cm ² is preferable. When the light irradiation intensity to the active energy ray curable resin composition is less than 10 mW / cm ² , the reaction time becomes too long, and when it exceeds 2500 mW / cm ² , the heat radiated from the lamp and the active energy ray curable property. There is a possibility that yellowing of the active energy ray-curable resin composition or deterioration of the polarizing film may occur due to heat generation during polymerization of the resin composition. The light irradiation time to the active energy ray-curable resin composition is also controlled for each composition and is not particularly limited, but the integrated light amount expressed as the product of irradiation intensity and irradiation time is 10 to 2500 mJ / It is preferably set to be cm ² . If the integrated light amount to the active energy ray-curable resin composition is less than 10 mJ / cm ² , the generation of the active species derived from the polymerization initiator may not be sufficient, and the resulting adhesive layer may be insufficiently cured. There is. On the other hand, if the integrated light quantity exceeds 2500 mJ / cm ² , the irradiation time becomes very long, which is disadvantageous for improving productivity. In addition, it is preferable that irradiation of an active energy ray is performed in the range in which various performances, such as the polarization degree of a polarizing film and a transmittance | permeability, do not fall.

<Liquid crystal display device>
In the optical laminate of the present invention, another liquid crystal cell substrate is disposed on the opposite side of the surface of the liquid crystal cell substrate 1 to which the polarizing plate 5 is bonded, and the liquid crystal is sandwiched between the two. A liquid crystal cell or a liquid crystal panel can be used. A liquid crystal display device is configured using the liquid crystal cell or the liquid crystal panel as a display element. The liquid crystal cell itself in a state in which liquid crystal is sealed between two liquid crystal cell substrates is used as the liquid crystal cell substrate 1 in FIGS. 1 and 2, and a polarizing plate is bonded to one or both surfaces according to the present invention to form a liquid crystal panel. It can also be. Since the optical layered body of the present invention is excellent in durability against thermal shock tests and the like, the liquid crystal display device produced as described above is also excellent in durability against thermal shock tests and the like. Thus, a reduction in thickness and weight is achieved.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited by these examples. In the examples, “parts” and “%” representing the amount used or content are based on weight unless otherwise specified.

(Production Example 1: Production of polarizing film)
A polyvinyl alcohol film having an average polymerization degree of about 2400 and a saponification degree of 99.9 mol% or more and a thickness of 75 μm was immersed in pure water at 30 ° C., and the weight ratio of iodine / potassium iodide / water was 0.02 / It was immersed in a 2/100 aqueous solution at 30 ° C. Then, it was immersed at 56.5 ° C. in an aqueous solution having a potassium iodide / boric acid / water weight ratio of 12/5/100. Subsequently, the film was washed with pure water at 8 ° C. and then dried at 65 ° C. to obtain a polarizing film having a thickness of about 30 μm in which iodine was adsorbed and oriented on polyvinyl alcohol. Stretching was mainly performed in the iodine staining and boric acid treatment steps, and the total stretching ratio was 5.3 times.

(Production Example 2: Production of Polarizing Plate)
A transparent protective layer of a polarizing film is formed on one side of a polyethylene terephthalate (PET) film (Toyobo Co., Ltd., Toyobo Ester Film E7002) using a coating machine (Daiichi Rika Co., Ltd., bar coater). The active energy ray-curable resin composition having the following composition was applied.

[Active energy ray-curable resin composition for transparent protective layer]
3,4-Epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (Daicel Chemical Industries, Celoxide 2021P)
35 parts bis (3-ethyl-3-oxetanylmethyl) ether (Aron Oxetane OXT-221, manufactured by Toagosei Co., Ltd.)
15 parts Diacrylate of acetal compound of hydroxypivalaldehyde and trimethylolpropane (Shin-Nakamura Chemical Co., Ltd., A-DOG)
50 parts 2-hydroxy-2-methyl-1-phenylpropan-1-one (Ciba, DAROCUR 1173, photoradical polymerization initiator)
2.25 parts 4,4′-bis [diphenylsulfonio] diphenyl sulfide Bishexafluorophosphate-based photocationic polymerization initiator (manufactured by ADEKA, Adekaoptomer SP-150)
2.25 parts In addition, said A-DOG (diacrylate of the acetal compound of a hydroxypivalaldehyde and a trimethylol propane) is a compound which has a structure of the following Formula.

  In coating the active energy ray-curable resin composition, the film thickness varies depending on the viscosity. Therefore, the film thickness was adjusted by changing the number of the bar coater number. Next, on one surface of the polarizing film produced in Production Example 1, a PET film having a coating film of the active energy ray-curable resin composition, so that the coating film side becomes a bonding surface with the polarizing film, It bonded using the sticking apparatus (The Fuji Plastics Co., Ltd. make, LPA3301).

The bonded product was irradiated with ultraviolet light at an integrated light quantity of 1500 mJ / cm ² using a D bulb manufactured by Fusion UV Systems, and the active energy ray-curable resin composition disposed on one side of the polarizing film was cured. Thereafter, the PET film was peeled off, and a polarizing plate having a transparent protective layer made of a cured product of the active energy ray-curable resin composition on one side was produced. At this time, the thickness of the polarizing plate was about 35 μm.

(Production Example 3: Preparation of adhesive composition)
The following components were mixed to obtain an ultraviolet curable adhesive composition.

[Ultraviolet curable adhesive composition]
3,4-Epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (Daicel Chemical Industries, Celoxide 2021P)
75 parts bis (3-ethyl-3-oxetanylmethyl) ether (Aron Oxetane OXT-221, manufactured by Toagosei Co., Ltd.)
25 parts 4,4′-bis [diphenylsulfonio] diphenyl sulfide Bishexafluorophosphate-based photocationic polymerization initiator (UVACURE 1590, manufactured by Daicel-Cytec Co., Ltd.)
5 parts Silicone leveling agent (SH710, manufactured by Toray Dow Corning Co., Ltd.)
0.2 part <Example 1>
The polarizing plate produced in Production Example 2 is cut into a sample size of 8 cm × 8 cm, and is produced on the surface where the transparent protective layer is not formed using a coating machine (manufactured by Daiichi Rika Co., Ltd., bar coater). The adhesive composition obtained in Example 3 was applied. At this time, since the film thickness when the adhesive composition was applied varied depending on the viscosity, the number of the bar coater was changed and the film thickness after curing was adjusted to 2 μm. Next, the polarizing plate which has the coating film of the said adhesive composition on one side of a transparent glass substrate (what becomes a liquid crystal cell substrate), so that the coating film side may become a bonding surface with a transparent glass substrate. Then, pasting was performed using a pasting apparatus (manufactured by Fuji Plastic Co., Ltd., LPA3301). This bonded product was irradiated with ultraviolet rays with an integrated light amount of 1500 mJ / cm ² by a D bulb manufactured by Fusion UV Systems, and the adhesive composition was cured, thereby producing an optical laminate.

<Example 2>
Instead of the polarizing plate produced in Production Example 2, a protective film made of triacetyl cellulose (TAC) having a thickness of 40 μm on one side of a polarizing film in which iodine is adsorbed and oriented on the polyvinyl alcohol film via a polyvinyl alcohol-based adhesive. An optical laminate was prepared in the same manner as in Example 1 except that a polarizing plate (Sumitomo Chemical Co., Ltd., SR0661A-XNSY, thickness of about 70 μm) was used.

<Comparative Example 1>
An acrylic pressure-sensitive adhesive is used instead of the ultraviolet curable adhesive composition, and the transparent protective layer of the polarizing plate produced in Production Example 2 is provided on one surface of the transparent glass substrate via the acrylic pressure-sensitive adhesive. An optical laminate was produced in the same manner as in Example 1 except that the non-coated surface (polarizing film surface) was bonded and treated in a 50 ° C. autoclave at a pressure of 5 kg / cm ² (about 0.5 MPa) for 20 minutes. did.

<Comparative example 2>
An acrylic pressure-sensitive adhesive is used in place of the ultraviolet curable adhesive composition, and the surface on which the protective film of the polarizing plate is not bonded to one surface of the transparent glass substrate via the acrylic pressure-sensitive adhesive (polarizing film surface) ), And an optical laminate was produced in the same manner as in Example 2 except that it was treated in a 50 ° C. autoclave at a pressure of 5 kg / cm ² (about 0.5 MPa) for 20 minutes.

<Adhesion durability test>
The durability of the optical laminates produced in the above examples and comparative examples was evaluated by the following method.

[Durability test method]
A heat resistance test was performed in which the optical laminate was stored for 500 hours under dry conditions at a temperature of 90 ° C. Moreover, the process of hold | maintaining at -35 degreeC for 1 hour and the process hold | maintained at 70 degreeC for 1 hour were made into 1 cycle, and the heat shock test which repeated this 300 times was done. In both tests, the polarizing plate after the test was visually observed and evaluated according to the following criteria. The results are shown in Table 1.

(Heat resistance test)
○: Almost no change in appearance such as floating, peeling or foaming.
Δ: Appearance changes such as floating, peeling and foaming are slightly noticeable.
X: Remarkable changes in appearance such as floating, peeling, foaming, etc.

(Heat shock test)
○: No cracks or cracks are observed in the polarizing film.
X: Cracks and cracks are observed in the polarizing film.

  The optical laminated body of Example 1 uses a polarizing plate having the same thickness as that of Comparative Example 1, and the optical laminated body of Example 2 uses a polarizing plate having the same thickness as that of Comparative Example 2. However, the optical laminates of Examples 1 and 2 according to the present invention are thin and lightweight, and are cured with active energy rays (ultraviolet rays) containing an epoxy compound for bonding between the polarizing plate and the glass substrate. It can be seen that excellent durability is exhibited by using the adhesive of the conductive resin composition.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Liquid crystal cell substrate, 2 Adhesive layer, 5 Polarizing plate, 6 Polarizing film, 7 Transparent protective layer, 8 Resin layer 10, 11, 12 Optical laminated body.

Claims (4)

A liquid crystal cell substrate;
A thickness formed from an active energy ray-curable resin composition that is laminated in contact with the surface of the liquid crystal cell substrate and contains an epoxy compound having at least one epoxy group in the molecule and a photocationic polymerization initiator. and the adhesive layer but Ru der less than 2μm,
A polarizing plate having a thickness of 100 μm or less, having a polarizing film laminated in contact with the surface of the adhesive layer and having a dichroic dye adsorbed and oriented on a polyvinyl alcohol-based resin;
With
The polarizing plate is
The polarizing film laminated in contact with the surface of the adhesive layer;
The optical laminated body comprised with the transparent protective layer 1 layer laminated | stacked on the surface on the opposite side to the said adhesive bond layer in the said polarizing film.   The optical laminate according to claim 1, wherein the active energy ray-curable resin composition further contains an oxetane compound. The transparent protective layer is composed of a cured product of the configuration of a thermoplastic resin film, or an active energy ray curable resin composition, the thickness is 50μm or less claim 1 or 2 optical laminate according to . An epoxy compound having at least one epoxy group in the molecule on the surface of the polarizing film of a polarizing plate having a thickness of 100 μm or less having a polarizing film in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin, and Forming an uncured adhesive layer comprising an active energy ray-curable resin composition containing a cationic photopolymerization initiator;
Bonding the uncured adhesive layer formed on the surface of the polarizing film to the liquid crystal cell substrate;
And irradiating an active energy ray, the thickness of cured adhesive layer of the uncured you form an adhesive layer is 2μm or less steps,
The manufacturing method of an optical laminated body provided with this.

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