JPH11314313A - Plastic laminate - Google Patents

Abstract

(57) [Summary] [Problem] Lighter than one using a glass substrate,
A plastic laminate excellent in optical properties, mechanical strength, and the like, which can be suitably used for substrates such as a liquid crystal display device, a touch panel, and a solar cell conversion element is provided. SOLUTION: A plastic laminate characterized in that the following A, B, C are laminated in this order. Usually, a conductive film is further laminated on the photocurable resin layer of the laminate. A: Photocurable resin B: Gas barrier film C: Cured film

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic laminate suitably used for substrates such as a liquid crystal display, a touch panel and a solar cell conversion element.

[0002]

2. Description of the Related Art With the rapid progress of electronics technology, the field of optoelectronics, especially liquid crystal display devices, touch panels, solar cell conversion elements, etc., is expanding. 2. Description of the Related Art In general, an optoelectronic element is provided for various uses by forming the element on a glass substrate having a transparent conductive layer. However, glass has a large weight, and when incorporated into a portable device, there is a problem that the weight of the equipment increases due to the large specific gravity of the glass. Therefore, weight reduction is strongly desired, and a sheet substrate made of polyarylate, polyethersulfone, polycarbonate, or the like, which is relatively excellent in strength, transparency, heat resistance, and the like, is being used as a plastic sheet instead of a glass substrate.

However, these sheet substrates at present have a thickness of about 0.1 mm and thus lack rigidity as compared with conventional glass substrates. In order to impart rigidity, it is conceivable to increase the film thickness. However, in the solvent casting method, production of about 0.2 mm in thickness is practically limited due to problems of foaming, reduction in flatness, and residual solvent. . For application to liquid crystal devices, the sheet substrate usually has a birefringence of 20 n.
m or less, preferably 10 nm or less, but it is difficult to produce a molded article having low birefringence which is easily affected by molecular orientation during plastic molding. Therefore, Japanese Patent Application Laid-Open No. 7-36023 and the like have proposed an optical plastic sheet in which two sheets of sheets having a small birefringence are laminated. However, since such a sheet is a thermoplastic resin, the sheet has low rigidity. Also, there is a drawback that the chemical resistance is significantly poor. Also, JP-A-6-116406
In the publication, a sheet in which the surface layer of a base sheet is coated with a curable resin as an optical sheet has been proposed, but such a sheet is also swollen by a solvent from the side of the sheet when washing the substrate, and as a result, There is a problem that the chemical resistance is poor and the rigidity of the substrate is not sufficient.

Further, in the field of optoelectronic devices,
In particular, since a high degree of optical characteristics, gas barrier properties, electrical conductivity, mechanical strength, and the like are required, a substrate having a multilayer structure composed of a plurality of layers or films having various functions is actually used. No. 5308 discloses that a cured film is provided on both surfaces of a plastic molded body, and a conductive film is provided on one surface.
On the other hand, a laminate in which a metal oxide film is provided on one side has been proposed. However, this laminated body has a problem that cracks are likely to occur during heating due to a difference in properties of each layer and a problem of adhesion, in addition to the problem of the base sheet alone.

On the other hand, although a plastic sheet substrate is useful as a glass substitute substrate, it is necessary not only to be light in weight but also to have flexibility in order to increase the utility value. That is, when the substrate is bent (bent) at a certain curvature, it is necessary that the conductive film does not crack and the electrical conductivity is maintained. However, the conventional plastic sheet substrate has a problem that its bending resistance is insufficient.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a plastic laminate having sufficient bending resistance as a substrate for a liquid crystal device, a touch panel, a solar cell, and the like.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that various physical properties of a plastic laminate having a specific structure including a photocurable resin as a substrate are included. Noting that it is remarkably superior, the present invention has been reached. That is, the present invention resides in a plastic laminate characterized in that the following A, B, and C are laminated in this order. A: Photocurable resin B: Gas barrier film C: Cured film

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the plastic laminate of the present invention will be described in more detail. (Photo-curable resin layer) The photo-curable resin layer constitutes the base layer of the plastic laminate of the present invention. The photocurable resin that forms the photocurable resin sheet serving as the base material layer is a resin that is cured by irradiation with ultraviolet light or the like. Specifically, a resin composition comprising an acrylate compound having a radically reactive unsaturated compound, a resin composition comprising this acrylate compound and a mercapto compound having a thiol group, epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, etc. And the like, but are not limited thereto.

Among them, at least one selected from sulfur-containing bis (meth) acrylate represented by the formula (1) and alicyclic skeleton bis (meth) acrylate represented by the formula (2)
A composition comprising a kind of bis (meth) acrylate is preferable in terms of chemical resistance, rigidity and the like. “(Meth) acrylate” is a generic term for acrylate or methacrylate.

[0010]

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[In the formula (1), R ¹ and R ² may be different from each other and represent a hydrogen atom or a methyl group. R ³ is a hydrocarbon group having 1 to 6 carbon atoms which may have an oxygen atom and / or a sulfur atom in the carbon chain, preferably 2 to 4 carbon atoms.
Represents an alkylene group. R ⁴ represents a hydrocarbon group having 1 to 6 carbon atoms which may have an oxygen atom and / or a sulfur atom in the carbon chain, preferably an alkylene group having 1 to 3 carbon atoms. X represents a halogen atom, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, and a represents an integer of 0 to 4. However, when a is an integer of 2 or more, a plurality of Xs may be different from each other. Some examples of the compound represented by the formula (1) are as follows. p-bis (β-methacryloyloxyethylthiomethyl) benzene, p-bis (β-acryloyloxyethylthiomethyl) benzene, m-bis (β-
Methacryloyloxyethylthiomethyl) benzene, m
-Bis (β-acryloyloxyethylthiomethyl) benzene, p-bis (β-methacryloyloxyethyloxyethylthiomethyl) benzene, p-bis (β-methacryloyloxyethylthioethylthiomethyl) benzene, p-bis (β -Methacryloyloxyethylthiomethyl) tetrabromobenzene, m-bis (β-methacryloyloxyethylthiomethyl) tetrachlorobenzene. These compounds are described in, for example, JP-A-62-1953.
No. 57 can be synthesized.

[0012]

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In the formula (2), R^FiveAnd R⁶Are different from each other
And may represent a hydrogen atom or a methyl group. b is 1 or
Represents 2 and c represents 0 or 1. When some of the compounds represented by the formula (2) are exemplified,
It is as follows. Bis (oxymethyl) tricyclo [5.
2.1.0^2,6] Decane = diacrylate, bis (e
Xymethyl) tricyclo [5.2.1.0^2,6] Deca
Dimethacrylate, bis (oxymethyl) tris
B [5.2.1.0^2,6] Decane = acrylate meta
Acrylate, bis (oxymethyl) pentacyclo [6.
5.1.1^3,6. 0^2,7. 0^{9, 13}Pentadecane =
Diacrylate, bis (oxymethyl) pentacyclo
[6.5.1.1.^3,6. 0^2,7. 0^{9, 13}Penta
Decane dimethacrylate, bis (oxymethyl) pen
Tacyclo [6.5.1.1. ^3,6. 0^2,7. 0^{9, 13}]
Pentadecane acrylate methacrylate. these
The compound is described in, for example, JP-A-62-225508.
It can be synthesized by the disclosed methods.

The (meth) acrylates represented by the above formulas (1) and (2) can be used alone or in combination of two or more. When the compound of the formula (1) is used alone, the low birefringence plate obtained according to the present invention has a refractive index of 1.54 to 1.65 at room temperature at a D line (589.3 mm) of sodium, and has a high refractive index. Having. When the compound of the formula (2) is used alone, the refractive index is relatively low, from 1.47 to 1.51. Therefore, a low birefringent plate having a desired refractive index between 1.47 and 1.65 can be obtained by using two or more compounds represented by the formulas (1) and (2) in combination.

The photocurable resin can be used by polymerizing the above bis (meth) acrylate alone.
At least one mercapto compound selected from mercapto compounds having two or more thiol groups in the molecule represented by the following formulas (3), (4) and (5) is bis (meth) acrylate 80 to 99.1. With respect to parts by weight, 0.
By mixing 1 to 20 parts by weight, more preferably 1 to 15 parts by weight, and still more preferably 5 to 10 parts by weight, it is possible to reduce birefringence and impart appropriate toughness. If the amount of the mercapto compound is more than 20 parts by weight, heat resistance is lowered, which is not preferred.

[0016]

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[In the formula (3), a plurality of R ⁷ may be different from each other and each represents a methylene group or an ethylene group.
R ⁸ is 2 to 15 carbon atoms which may contain an oxygen atom and / or sulfur atom in the carbon chain, preferably a hydrocarbon residue of 2-6. d shows the integer of 2-6. That is, the compound represented by the formula (3) is a diester to hexaester of thioglycolic acid or thiopropionic acid and a polyol. Some examples are pentaerythritol tetrakis (β-thiopropionate), pentaerythritol tetrakis (thioglycolate), trimethylolpropane tris (β-thiopropionate), and trimethylolpropane tris (thioglycolate). , Diethylene glycol bis (β-thiopropionate), diethylene glycol bis (thioglycolate), triethylene glycol bis (β-thiopropionate), triethylene glycol bis (thioglycolate), dipentaerythritol hexakis (β
-Thiopropionate), dipentaerythritol hexakis (thioglycolate) and the like.

[0018]

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[In the formula (4), Y may be different from each other, and HS- (CH ₂ ) _e- (CO) (OCH ₂ -C
_{H 2) f - (CH 2} ) g - shows a. Here, e represents an integer of 1 to 4, f represents an integer of 1 to 4, and g represents an integer of 0 to 2, respectively. That is, the compound of the formula (4) is an ω-SH group-containing triisocyanurate. Some examples are tris [2- (β-thiopropionyloxy) ethyl] isocyanurate, tris (2-thioglyconyloxyethyl) isocyanurate, and tris [2- (β-thiopropionyloxyethoxy) ethyl]. Examples include isocyanurate, tris (2-thioglyconyloxyethoxyethyl) isocyanurate, tris [3- (β-thiopropionyloxy) propyl] isocyanurate, and tris (3-thioglyconyloxypropyl) isocyanurate.

[0020]

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[In the formula (5), R ⁹ and R ¹⁰ may be different from each other and represent a hydrocarbon group having 1 to 3 carbon atoms. m and n each represent 0 or 1. p represents 1 or 2. That is, the compound of the formula (5) is an α, ω-SH group-containing compound. Some examples thereof include benzenedimercaptan, xylylenedimercaptan, and 4,4'-dimercaptodiphenylsulfide.

Other monomers used in the polymerization of the photocurable resin include, for example, methyl (meth) acrylate, phenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, methacryloyloxy Methyltetracyclododecane, methacryloyloxymethyltetracyclododecene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2,2-bis [4- (β -Methacryloyloxyethoxy) phenyl] propane, 2,2 '
-(Meth) acrylate compounds such as -bis [4-([beta] -methacryloyloxyethoxy) cyclohexyl] propane, 1,4-bis (methacryloyloxymethyl) cyclohexane, trimethylolpropane tri (meth) acrylate, styrene, chlorostyrene and divinyl Core and / or side chain substituted and unsubstituted styrenes such as benzene and α-methylstyrene. Among these other monomers, methacryloyloxymethylcyclododecane, 2,2-bis [4- (β-methacryloyloxyethoxy) phenyl] propane, 2,2-bis [4- (β
-Methacryloyloxyethoxy) cyclohexyl] propane, 1,4-bis (methacryloyloxymethyl)
Cyclohexane, and mixtures thereof, are particularly preferred.
Further, these may contain small amounts of antioxidants, ultraviolet absorbers, dyes and pigments, fillers and the like.

The bis (meth) acrylate or a mixture of the bis (meth) acrylate and the mercapto compound as described above is cured by a known radical polymerization in which a photopolymerization initiator which generates a radical by active energy rays such as ultraviolet rays is added. Let it. As the photopolymerization initiator used at that time, for example, benzophenone, benzoin methyl ether, benzoin isopropyl ether, diethoxyacetophenone, 1-hydroxycyclohexylphenyl ketone, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethyl Benzoyldiphenylphosphine oxide and the like. Preferred photoinitiators are 2,4,6-trimethylbenzoyldiphenylphosphine oxide and benzophenone. Two or more of these photopolymerization initiators may be used in combination.

The amount of the photopolymerization initiator added is 100
0.01 to 1 part by weight, preferably 0.02 part by weight based on part by weight
０．３0.3 parts by weight. If the amount of the photopolymerization initiator is too large, the polymerization proceeds rapidly, causing not only an increase in birefringence but also a deterioration in hue. If the amount is too small, the composition cannot be cured sufficiently. The amount of the active energy rays to be irradiated is arbitrary as long as the photopolymerization initiator generates radicals.However, if the amount is extremely small, the heat resistance and mechanical properties of the cured product are sufficiently exhibited due to incomplete polymerization. On the contrary, if the amount is extremely excessive, deterioration of the cured product due to light such as yellowing occurs. Therefore, ultraviolet rays having a wavelength of 200 to 400 nm are preferably 0 to 400 nm depending on the composition of the monomer and the type and amount of the photopolymerization initiator. Irradiate in the range of 1 to 200 J. Specific examples of the lamp to be used include a metal halide lamp and a high-pressure mercury lamp.

For the purpose of promptly completing the curing, thermal polymerization may be used in combination. That is, the composition and the whole mold are usually heated in the range of 30 to 300 ° C. simultaneously with the light irradiation. In this case, a radical polymerization initiator may be added in order to complete the polymerization better, but excessive use causes an increase in birefringence and a deterioration in hue. Specific examples of the thermal polymerization initiator include benzoyl peroxide, diisopropyl peroxy carbonate, t-butyl peroxy (2-ethylhexanoate), and the amount used is 1 part by weight or less based on 100 parts by weight of the monomer. Is preferred.

Furthermore, after the radical polymerization by light irradiation is performed, the cured product is heated to reduce the completion of the polymerization reaction and the internal strain generated during the polymerization. The heating temperature is appropriately selected according to the composition of the cured product and the glass transition temperature. However, since excessive heating results in deterioration of the hue of the cured product, a temperature around the glass transition temperature or lower is preferable.

The molding method of the photocurable resin sheet is such that a cavity is formed by a spacer or the like using two opposing flat plates (hereinafter, referred to as a "molding die") at least one surface of which is capable of transmitting active energy rays, and a peripheral portion is formed. The photocurable resin is injected into a sealed injection mold, and irradiated with active energy rays to cure the photocurable resin. The material of the mold, from the surface of the sheet after curing, preferably using polished glass,
Any material may be used as long as it has sufficient transmittance of active energy rays to cure the photocurable resin and does not easily deform its shape due to heat or the like. Moreover, plastics, such as an acrylic plate, which can obtain surface properties equivalent to a polished glass are mentioned.

If necessary, a release agent or the like may be applied on the mold, or a release layer may be provided so that the cured photocurable resin sheet can be easily removed from the mold. The release agent to be used, the release layer, its application method and the like are not particularly limited, but a substance having sufficient transmittance of active energy rays to cure the photocurable resin, and furthermore, a photocurable resin. Any substance may be used as long as it is a substance that does not easily change its state of formation due to active energy rays for curing, heat generated during curing, or the like, and has a flatness comparable to that of a glass surface.

The active energy ray cures the photocurable resin, and includes, for example, ultraviolet rays. The irradiation amount of the active energy ray may be an amount that cures the photocurable resin to be used. The spacers and the like for forming the cavities are not particularly limited, as long as the desired sheet thickness can be obtained. For example, a plate or bar made of rubber or metal such as silicon rubber, or a plate or bar made of resin such as Teflon may be used. (Gas barrier film) Examples of the film in the present invention include an inorganic oxide film, and a gas barrier resin layer such as an ethylene-vinyl alcohol copolymer (for example, EVAL, trade name EVAL, Soarnol) or vinylidene chloride. Preferably, it is an inorganic oxide film. What is an inorganic oxide?
These are oxides of metals, nonmetals, and submetals. Specific examples include aluminum oxide, zinc oxide, antimony oxide, indium oxide, calcium oxide, cadmium oxide, silver oxide, gold oxide, chromium oxide, silicon oxide, and cobalt oxide. , Zirconium oxide, tin oxide, titanium oxide, iron oxide, copper oxide, nickel oxide, platinum oxide, palladium oxide, bismuth oxide, magnesium oxide, manganese oxide, molybdenum oxide, vanadium oxide, barium oxide, and the like. Is particularly preferred. In addition, in the inorganic oxide,
Trace amounts of metals, non-metals, sub-metals and their hydroxides,
Further, carbon or fluorine may be appropriately contained in order to improve flexibility. Examples of a method of forming the gas barrier layer include a method of coating a resin or the like and a method of forming a vapor deposition film made of an inorganic oxide. As a method for forming the deposited film, a conventionally known method such as a vacuum deposition method, a vacuum sputtering method, an ion plating method, and a CVD method can be used.

The thickness of the above-mentioned gas barrier film is not particularly limited, and varies depending on the type of the constituent components of the gas barrier film. ~ 50 nm is preferred.
In order to obtain a more advanced oxygen gas barrier property and a higher water vapor barrier property, the thickness of the film may be increased.
If it is less than 10 nm, the film may be in an island shape and a portion where the film is not formed may be generated, and a uniform film may not be obtained. (Curing film) The cured film in the present invention is not particularly limited as long as it is an organic compound-based cured film, and is formed from a hard coating agent, an anchor coating agent (primer coating agent) or the like. is there. As a specific example, as the hard coat agent, an acrylate such as polyurethane acrylate or epoxy acrylate or a polyfunctional acrylate, a photopolymerization initiator, and an organic solvent as main components can be used. Examples of the anchor coating agent include known anchor coating agents such as isocyanate-based, polyurethane-based, polyester-based, polyethyleneimine-based, polybutadiene-based and alkyl titanate-based agents. These resins are
It can be used alone or in combination of two or more kinds. Further, three-dimensional crosslinking can be performed using various curing agents, crosslinking agents and the like.

Particularly preferable examples of the cured film include a silicone resin as an organic polymer when various properties such as surface hardness, heat resistance, chemical resistance, and transparency are taken into consideration. The active energy ray-curable composition containing a silane coupling agent having an acryloyl group or a methacryloyl group is particularly preferable. When an active energy ray-curable composition containing a silane coupling agent having an acryloyl group or a methacryloyl group is used, in particular, the adhesion between a gas barrier film made of a metal oxide or the like and a cured film is improved, and the gas barrier property is improved. Especially improve. Although the reason is not clear, the improvement in adhesion is due to the fact that the silane coupling agent chemically reacts with the metal oxide thin film and reacts with other film formations where acryloyl groups and methacryloyl groups of the silane coupling agent coexist. It is considered that the cured film is firmly bonded to the metal oxide thin film. In addition, improvement of gas barrier property,
It is considered that the gap between the metal oxide particles constituting the metal oxide thin film is filled with a silane coupling agent or a film forming component reacted with the acryloyl group or methacryloyl group.

The silane coupling agent may have at least one of an acryloyl group and a methacryloyl group, but preferably has an acryloyl group having a high reaction rate. For example, if a silane coupling agent having only an isocyanate group or a mercapto group as a reactive group and not having an acryloyl group or a methacryloyl group is used, the adhesion is not improved. This seems to be due to the fact that even though the bond between the silane coupling agent and the metal oxide thin film is formed, the silane coupling agent reacts with other co-existing film formations and is hardly taken into the film. It is.

Examples of the silane coupling agent having an acryloyl group or a methacryloyl group include γ-acryloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyl Triethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-acryloxypropylmethyldiethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxypropyl-tris ( β
-Methoxyethoxy) silane, γ-methacryloxypropyl-tris (β-methoxyethoxy) silane, and the like.

These silane coupling agents generally account for 0.1 to 60% by weight, preferably 0.2 to 45% by weight, of the active energy ray-curable composition. If the amount of the silane coupling agent is too small, it is difficult for the adhesion between the cured film and the metal oxide thin film to be sufficiently exhibited. This is presumably because the amount of the functional group that reacts with the metal oxide thin film in the composition is not sufficient. Conversely, if the silane coupling agent is present in excess, the alkali resistance of the cured film may decrease. This is probably because a large amount of the silane coupling agent that does not react with the metal oxide thin film remains in the cured film and reacts with the alkali.

The active energy ray-curable composition comprises a conventional monomer, oligomer, polymer, or the like which is polymerized by irradiation with an active energy ray to form a cured film, except for containing a silane coupling agent. For example, monomers or oligomers such as epoxy (meth) acrylate, urethane (meth) acrylate, and polyester (meth) acrylate are used. Examples of some of these include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexaacrylate. Monofunctional and polyfunctional acrylic monomers, methacrylic monomers, and vinyl monomers having one or more carbon-carbon double bonds, such as methacrylate, isoamyl acrylate, ethoxydiethylene glycol acrylate, methoxydiethylene glycol acrylate, and N-vinylpyrrolidone. Further, the active energy ray-curable composition may contain known additives such as an ultraviolet absorber and a thermal polymerization inhibitor.

In order to form a cured film with the active energy ray-curable composition, the active energy ray-curable composition is applied by various coating methods such as a gravure coating method, a reverse coating method, a die coating method and the like, and the active energy ray is applied. Irradiation and curing may be used. At this time, preheating may be performed after application and before curing. When the active energy ray-curable composition is diluted with a solvent, the solvent must be removed in this preheating step.

The above composition is usually preferably diluted with a volatile solvent and applied as a liquid composition. Although what is applied as a solvent is not particularly limited, it is required that the surface properties of the object to be applied are not impaired in use. Furthermore, stability of the composition, wettability to the substrate,
The solvent should be determined in consideration of volatility and the like. Further, the solvent may be used as a mixture of not only one kind but also two or more kinds. Examples of the solvent include alcohols, esters, ethers, ketones, halogenated hydrocarbons, aromatic hydrocarbons such as toluene and xylene, and aprotic polar solvents.

The cured film has an improved surface hardness, a controlled refractive index, an improved mechanical strength, an improved thermal characteristic, and an improved durability of the metal oxide film and the transparent conductive film provided on the cured film. For the purpose, etc., inorganic fine particles are added. Such inorganic fine particles are not particularly limited as long as they do not impair transparency in a film state. A particularly preferred example from the viewpoint of improving workability and imparting transparency is a sol dispersed in a colloidal state. More specific examples include silica sol, antimony oxide sol, titania sol, alumina sol, zirconia sol, tungsten oxide sol, and the like. The addition amount of the inorganic fine particles is not particularly limited, but in order to make the effect more remarkable, it is preferable that the content is 1% by weight or more and 80% by weight or less in the transparent coating. If the amount is less than 1% by weight, a clear effect of the addition is hardly recognized, and if it exceeds 80% by weight, problems such as poor adhesion to the transparent resin and cracks in the coating itself occur, resulting in a decrease in impact resistance. There are cases. The particle diameter of the inorganic fine particles is not particularly limited, but is preferably 1 to 300 mμ,
More preferably, those having 5 to 100 mμ are used.
When the particles having an average particle diameter of more than 300 μm are used, the resulting film tends to be poor in transparency and turbid. Further, in order to improve the dispersibility of the particulate inorganic material, various kinds of fine particle surface treatments may be performed, and there is no problem even if various surfactants, amines and the like are added.

Various curing agents may be used in combination with the coating composition used at the time of forming the cured film for the purpose of accelerating curing and curing at a low temperature. As the curing agent, various epoxy resin curing agents or various organic silicon resin curing agents are used. Specific examples of these curing agents include various organic acids and their acid anhydrides, nitrogen-containing organic compounds, various metal complex compounds, metal alkoxides, various salts such as organic carboxylate and carbonate of alkali metals, and salts of organic acids. Examples thereof include oxides and radical polymerization initiators such as azobisisobutyronitrile. These curing agents can be used as a mixture of two or more kinds. Among these curing agents, an aluminum chelate compound is particularly useful from the viewpoint of the stability of the coating composition, the presence or absence of coloring of the film after coating, and the like.

The aluminum chelate compound referred to here
For example, the general formula AIXn Y _3-n Al indicated by
It is a minium chelate compound. Where X in the formula is O
L (L represents a lower alkyl group), Y is a general formula M¹ CO
CH_Two COM^Two (M¹, M^TwoAre lower alkyl groups)
And a ligand derived from the compound represented by the general formula M ^Three C
OCH_Two COOM^Four (M^Three , M^Four Are low-grade alk
Selected from the ligands derived from the compounds represented by
At least one, and n is 0, 1 or 2. one
General formula AlX_nY_3-n Aluminum chelation indicated by
Examples of the compound include various compounds.
Such as solubility in products, stability, and effect as a curing catalyst
Particularly preferred from a viewpoint is aluminum acetyl alcohol.
Cetonate, aluminum bisethyl acetoacetate
Monoacetylacetonate, aluminum di-n-butyl
Toxide-monoethyl acetoacetate, aluminum
-Di-iso-propoxide-monomethylacetoacete
And so on. These are used by mixing two or more kinds.
It is also possible.

Various types of surfactants are added to the coating composition used for forming the cured film in order to improve the flow during application and improve the smoothness of the transparent film to lower the coefficient of friction of the film surface. It is also possible. As the surfactant, a block or graft copolymer of dimethylpolysiloxane and alkylene oxide, a fluorine-based surfactant, and the like are particularly effective.

An inorganic oxide other than the inorganic fine particles can be added to the coating composition used for forming the cured film as long as the film performance and the transparency are not significantly reduced. The combined use of these additives can improve various properties such as adhesion to a substrate, chemical resistance, surface hardness, and durability. Examples of the inorganic material that can be added include a metal alkoxide, a chelate compound and / or a hydrolyzate thereof represented by the following general formula (C).

M (OR) m (C) Here, M is silicon, titanium, zircon, antimony, tantalum, germanium, aluminum or the like. R is an alkyl group, an acyl group, or an alkoxyalkyl group. m is the same value as the number of charges of the metal M. The cured film is obtained by curing the coating composition, and the curing is performed by a heat treatment. The heating temperature is appropriately selected in consideration of the composition of the coating composition and the heat resistance of the transparent crosslinked resin, but is preferably 50 to 2
50 ° C. As a method of applying the coating on the transparent resin, brush coating, dip coating, roll coating, spray coating,
Conventional coating methods such as spin coating and flow coating can be easily used. In applying the coating composition, it is also an effective means to perform various pretreatments for the purpose of improving cleaning, adhesion, and water resistance. Particularly preferred pretreatments include an activation gas treatment, a chemical treatment, and an ultraviolet treatment. It is sufficiently possible to carry out these pretreatments continuously or stepwise in combination.

The thickness of the cured film is not particularly limited, but is usually 0.1 to 50 μm, preferably 0.3 to 10 μm from the viewpoint of maintaining the adhesive strength and hardness.
m. In applying the coating, the coating composition is used after being diluted with various solvents for the purpose of controlling the workability and the thickness of the coating. As the diluting solvent, for example, water, alcohols, esters, ethers, halogenated hydrocarbons, dimethylformamide, dimethylsulfoxide and the like can be variously used depending on the purpose, and a mixed solvent can be used if necessary. is there. A polar solvent such as water, alcohol, dimethylformamide, ethylene glycol, diethylene glycol, triethylene glycol, benzyl alcohol, phenethyl alcohol, and phenyl cellosolve is preferably used from the viewpoint of the dispersibility of the particulate inorganic oxide. (Conductive Film) In the plastic laminate of the present invention, a laminate in which a conductive film is laminated on a photocurable resin layer is preferably used as a liquid crystal display device substrate. As a conductive material forming this conductive film, indium oxide, tin oxide, gold, silver,
Copper, nickel and the like can be mentioned, and these can be used alone or in combination of two or more. Among them, usually, indium tin oxide (hereinafter referred to as “IT”) composed of a mixture of 99 to 90% of indium oxide and 1 to 10% of tin oxide
O ") is particularly preferred from the viewpoint of the balance between transparency and conductivity. The method for forming the transparent conductive film can be performed by using a conventionally known vacuum evaporation method, sputtering method, ion plating method, chemical vapor deposition method, or the like. Of these, the sputtering method is preferred from the viewpoint of adhesion. The thickness of the above-mentioned transparent conductive film is usually preferably in the range of 500 to 2000 ° from the viewpoint of the balance between transparency and conductivity.

Further, in order to be suitably used as a plastic laminate having high bending resistance for substrates in the field of optoelectronics such as a liquid crystal display device and a touch panel,
Generally, if the plastic laminate has a hardness of 2 GP or more in the conductive film and / or a stiffness of 1.5 μN / nm or more and / or a modulus (Young's modulus) of 15 GP or more, the laminate is generally bent. Also, the conductive film does not crack and the electric resistance value does not deteriorate. And, preferably, the hardness is 3 GP or more, and / or the stiffness is 1.5 μN / nm or more, and / or the modulus (Young's modulus) is 20 GP or more.

Generally, it is said that a film formed has an internal stress due to a difference in thermal expansion coefficient between the substrate (base) and the film, and that a large amount of the film tends to cause cracks in the film. Various methods are known for measuring the internal stress of the film, but cannot be applied to the plastic laminate for the following various reasons. (A) Measurement of the amount of deflection of a substrate after film formation is uncertain in the case of a plastic substrate because of the influence of heat and the like. (B) The method of obtaining from the lattice constant and the plane spacing of the crystal peak of thin film X-ray diffraction cannot be measured when the film is amorphous. (C) Measurement by Raman scattering is difficult because the base material is plastic.

Further, although the internal stress of the film is related to the occurrence of cracks when the film is at rest, such as after film formation,
Cracking when the plastic laminate is bent includes other factors. One of them is the quality of the film following the base sheet when the plastic laminate is bent. Cracks are likely to occur if the film does not follow the substrate sheet poorly. Hardness and elasticity can be considered as the evaluation as physical properties, and can be directly characterized as an influencing factor of the presence or absence of cracks in the film due to bending.

In order to make physical properties such as hardness of the conductive film to a specific value or more, the properties of the conductive film may be controlled. However, the layer structure and the properties of layers other than the conductive film in the laminate also have a great influence. . Note that since the substrate is made of plastic, the upper limit of the film forming temperature is low, and there is a limit to changing the physical properties of the conductive film even if other film forming conditions are changed. On the other hand, a cured film is relatively easy to change its physical properties in a wide range, such as by changing the formulation and curing conditions. (Layer Structure of Laminate) The plastic laminate of the present invention comprises the above photocurable resin (A), gas barrier film (B), and cured film (C) laminated in this order. It is formed by stacking a conductive film on a resin layer. FIG. 1 shows the most basic configuration as a laminate having such a configuration. Further, the plastic laminate of the present invention is not limited to the one shown in FIG. 1, and further has a structure shown in FIG. 2 in which a gas barrier film is interposed between a photocurable resin layer and a conductive film. The configuration in FIG. 3 in which a cured film is interposed between the resin layer and the conductive film, and the configuration in FIG. 4 in which a gas barrier film is interposed between the cured film and the conductive film are exemplified.

Gas barrier layer (B) on photocurable resin (A)
When the gas barrier layer is rubbed or scratched during handling of the laminated body due to contact of A and B, the barrier property may be greatly reduced. When the cured film (C) is laminated on the gas barrier layer, not only the gas barrier property is further improved, but even if there is rubbing or scratches during handling, the gas barrier property does not decrease much, resulting in a stable gas barrier property. Can be provided.

When a liquid crystal display device is obtained by laminating a conductive film on the laminate of the present invention, it is possible to obtain a good liquid crystal display device in which gas does not enter the cell, deterioration of the liquid crystal, and no bubbles are generated in the cell. Become. Furthermore, by inserting a gas barrier film in the eye of the conductive film and the cured resin layer, the barrier properties can be further improved, and the heat resistance of the conductive film can be further improved. When a cured film is inserted between the conductive film and the photocurable resin, the adhesion of the conductive film is improved, and a favorable film is obtained without peeling of ITO or the like. Furthermore, when a gas barrier film is inserted between the cured film and the conductive film, not only the gas barrier property is further improved than that of directly laminating the gas barrier film on the cured resin layer, and the heat resistance of the film is also improved. It may be particularly preferred. (Properties of Laminate) The plastic laminate of the present invention has 55 properties.
It is preferable that the light transmittance at a wavelength of light of 0 nm is 80% or more. When the light transmittance is less than 80%, in the case of color display or the like, the screen becomes dark, so that it is difficult to use it, and it tends to be used only for applications such as a monochrome display element. The birefringence of the plastic laminate is 20 nm.
The thickness is particularly preferably 10 nm or less. 20n
When it is larger than m, when a display panel is used, color unevenness of a display screen tends to occur.

On the other hand, the thickness of the plastic laminate is not more than 0.1.
10 to 2.00 mm is preferred. The transparent conductive sheet has a large flexural modulus, but if it is less than 0.10 mm, the sheet tends to bend under its own weight, and there is a tendency that the manufacturing process of a liquid crystal display device using a conventional glass substrate cannot be used,
If it exceeds 2.00 mm, the weight becomes the same as that of a conventional glass substrate of 1.5 to 0.7 mm, which deviates from the purpose of weight reduction.

As an application example of the plastic laminate of the present invention, for example, when it is used as a substrate for a liquid crystal display device, it usually has a configuration in which liquid crystal is sandwiched between plastic laminates. Further, a liquid crystal layer is sandwiched between substrates provided with an insulating film, if necessary, and an alignment film on the conductive film of the plastic laminate, if necessary. A deflection plate is provided outside the substrate holding the liquid crystal layer. In addition, the electroluminescent display element usually has a structure in which a light emitting layer, an insulating layer, and a back electrode are sequentially formed on the plastic laminate of the present invention, and the whole is further covered with a gas barrier layer. In this case, the light emitting layer contains zinc sulfide, cadmium sulfide, zinc selenide, etc., and the insulating layer contains yttrium oxide, thallium oxide, silicon nitride, etc.
Aluminum or the like is used for the back electrode.

[0053]

EXAMPLES Hereinafter, the contents and effects of the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. The plastic laminates obtained in Examples and Comparative Examples were evaluated by the following methods. <Film Thickness> Regarding the gas barrier film and the conductive film of the laminate obtained in Examples and Comparative Examples, the cross section of the laminate was observed with a transmission electron microscope (H-600, manufactured by Hitachi, Ltd.) Was measured for thickness. <Surface Resistance Value of Conductive Film> The surface resistance value was measured using a 4-terminal resistance meter (Lorester MP) manufactured by Mitsubishi Chemical Corporation. <Bending resistance test of conductive film> A plastic laminate having a size of 5 × 10 cm was placed along the long side with the conductive film on the inner side of φ2.
After winding the plastic laminate around a 5 mm stainless steel tube, the conductive film was wound outside, and then the presence or absence of cracks in the conductive film was examined with an optical microscope, and the surface resistance was measured by the above method. <Indentation test of conductive film> Pi manufactured by Hysitron
Using a coIndenter, one indentation (indenter indentation) was performed for 10 seconds at a load (μN) at which the indenter indentation depth was about one-tenth of the film thickness, and the average value was measured five times per sample. I asked. In each measurement, the distance between the measurement points was sufficiently large so that the influence of the indentation did not occur.
Further, the sample was sufficiently fixed on the sample stage. <Heat resistance> In the bigat softening test, the measurement conditions were as follows: indenter cross-sectional area 1.0 mm, load 5 kg, heating rate 50 ° C./h.
r, those in which the indenter penetrated 0.4 mm or more at 120 ° C. or less were ×, those that penetrated 0.2 to 0.4 mm were Δ, 0.1 m
When there was almost no approach below m, the result was marked as “○”. <Birefringence index> Birefringence measuring device (ODR, ADR
100), and the in-plane birefringence was measured at a wavelength of 632.8 nm. <Light transmittance> The transmittance at a wavelength of 550 nm was measured using a spectrophotometer manufactured by Hitachi, Ltd. <Roughness (Ra) of ITO film surface> Using a surface roughness measuring device (Surf Comb 575A, manufactured by Tokyo Seimitsu Co., Ltd.)
Diamond needle (1 μmR, 90 ° cone), measurement length 0.5 mm, cutoff value 0.16 mm, measurement speed 0.
The measurement was performed under the conditions of 06 mm / sec and linear correction. Example 1 100 parts by weight of bisoxymethyltricyclo [5.2.1.0 ^2,6 ] decane dimethacrylate and 2,4,6-trimethylbenzoyldiphenylphosphine oxide ("Lucillin TPO" manufactured by BASF) as a photoinitiator ") 0.
After uniformly mixing and stirring 05 parts by weight and 0.05 parts by weight of benzophenone, the composition was defoamed to obtain a composition. This composition was poured into an optically polished glass mold using a 0.4 mm thick silicon plate as a spacer, and an output of 80% on the glass surface was obtained.
40 / cm on the glass mold surface with a metal halide lamp of W / cm
After irradiation so as to have an energy of J / cm ² , the glass mold was released, and a photocurable resin sheet having a thickness of about 0.4 mm was obtained.

On the obtained cured resin sheet (A), a 10 nm thick silicon oxide thin film (B) was formed with a target material SIO using an argon gas total pressure of 6.7 E ⁻¹ Pa using an RF sputtering machine manufactured by ULVAC. Was. Further, components (a), (b), (c) and (d) shown below were added to the layer (B) at 62, 38, respectively.
5, 0.3% mixed, diluted with propylene glycol monomethyl ether, applied by spin coating,
5J / c with 80W / cm output metal halide lamp
The cured film (C) was laminated by irradiating so as to have an energy of m ² . Component a; bisoxymethyltricyclo [5.2.1.0
^2,6 ] decane diacrylate, upimer UV SA-1002 dicyclopentanyl diacrylate manufactured by Mitsubishi Chemical Corporation, Kayarad R684 manufactured by Nippon Kayaku Co., Ltd. Component b; a mixture of trimethylolpropane triacrylate, epoxy acrylate, etc., Japan Kayrad R130 manufactured by Kayaku Co., Ltd. Component c; 1-hydroxycyclohexylphenyl ketone and bis (2,6-dimethoxybenzoyl) -2,4,4
A mixture of trimethylpentylphosphine oxide, Irgacure 1800, manufactured by Ciba-Geigy Japan, Inc. Component d; polyether-modified silicon, Kyoeisha Chemical Co., Ltd.
Granol 450 The oxygen barrier of the laminate having the A / B / C layer structure is measured using an Oxy-Tran Oxy-Mocon meter at 23 ° C. and 80% humidity, and the oxygen barrier is 0.1 cc / m ^2.・
day or less. In addition, as a comparison, when the oxygen permeability of the cured resin sheet (A) was measured, it was 16 cc / m ^2.
And the oxygen permeability of the laminate having the A / B layer configuration was 1.5 cc / m ² · day.

Next, a cured film (C) composed of the same components a, b, c and d as described above is laminated on the layer A side surface of the laminate having the above-mentioned A / B / C layer constitution. Subsequently, using the same machine, oxygen partial pressure 1E ^-2 Pa, total pressure 6.7E ^-1 Pa, target material I
A 120 nm thick ITO film was formed with TO (tin oxide to indium oxide ratio: 95: 5) to obtain a plastic laminate. Table 1 shows the evaluation results of the laminate. Also,
The heat resistance, birefringence, light transmittance and roughness of the ITO film surface of the laminate were also measured, and all were good. Example 2 A plastic laminate was obtained in the same manner as in Example 1, except that the order of lamination was changed to an ITO film, a photocurable resin sheet, a silicon oxide thin film, and a cured film. Table 1 shows the evaluation results of the laminate. Further, the heat resistance of the laminate, birefringence,
The light transmittance and the roughness of the ITO film surface were also measured, and all were good. Example 3 A plastic laminate was obtained in the same manner as in Example 1, except that a silicon oxide thin film and an ITO film were formed by a DC sputtering machine manufactured by ULVAC. Table 1 shows the evaluation results of the laminate.
Shown in Further, the heat resistance, birefringence, light transmittance and roughness of the ITO film surface of the laminate were also measured, and all were good.

[0056]

[Table 1]

[0057]

The plastic laminate of the present invention is excellent in chemical resistance and rigidity, can use the conventional glass substrate process, and has excellent chemical resistance of the substrate, so that the transparent conductive film It has a particularly advantageous effect that it does not cause peeling or cracking, is lighter than a glass substrate, and has excellent impact resistance, and is extremely valuable in industrial use.

The plastic laminate of the present invention is preferably used as a substrate for a liquid crystal display device, and is provided with a TN (Twisted Nema).
Simple matrix type such as tic type, STN (Super Twisted Nematic type, ferroelectric liquid crystal) FLC (Ferroelectric Liquid Cristal) type, MIM (Metal-Insulator-Meta)
l) It can be applied to liquid crystal display devices such as an active matrix type such as a TFT type and a TFT (Thin-Film Transistor) type.

[Brief description of the drawings]

FIG. 1 shows one embodiment of the plastic laminate of the present invention.

FIG. 2 shows one embodiment of the plastic laminate of the present invention.

FIG. 3 shows one embodiment of the plastic laminate of the present invention.

FIG. 3 shows one embodiment of the plastic laminate of the present invention.

[Explanation of symbols]

 A: Photocurable resin B: Gas barrier film C: Cured film I: Conductive film

Claims (14)

[Claims] 1. A plastic laminate comprising the following layers A, B and C laminated in this order. A: Photocurable resin B: Gas barrier film C: Cured film 2. The plastic laminate according to claim 1, wherein a conductive film is laminated on the photocurable resin layer. 3. The plastic laminate according to claim 2, wherein a gas barrier film is interposed between the photocurable resin layer and the conductive film. 4. The plastic laminate according to claim 2, wherein a cured film is interposed between the photocurable resin layer and the conductive film. 5. The plastic laminate according to claim 2, wherein a gas barrier film is interposed between the cured film and the conductive film. 6. The plastic laminate according to claim 2, wherein the hardness of the conductive film is 2 GP or more. 7. The stiffness of the conductive film is 1.5 μN / n.
The plastic laminate according to any one of claims 2 to 6, wherein m is not less than m. 8. The plastic laminate according to claim 2, wherein the modulus of the conductive film is 15 GP or more. 9. A sheet in which a photocurable resin layer is formed by curing a composition comprising at least one bis (meth) acrylate selected from the following formulas (1) and (2) with active energy rays: Claim 1 characterized by the following.
8. The plastic laminate according to any one of 8. Embedded image [In the formula (1), R ¹ and R ² may be different from each other and represent a hydrogen atom or a methyl group. R ³ and R ⁴ may be different from each other and represent a hydrocarbon group having 1 to 6 carbon atoms which may have an oxygen atom and / or a sulfur atom in a carbon chain. X represents a substituent selected from a halogen atom, an alkyl group having 1 to 6 carbon atoms and an alkoxy group having 1 to 6 carbon atoms, and a represents an integer of 0 to 4. However, when a is an integer of 2 or more, a plurality of Xs may be different from each other. ] [In the formula (2), R ⁵ and R ⁶ may be different from each other and represent a hydrogen atom or a methyl group. b represents 1 or 2, and c represents 0 or 1. ] 10. A photocurable resin sheet comprising 80 to 99.9 parts by weight of at least one bis (meth) acrylate selected from the formulas (1) and (2) and the following formulas (3), (4) and (5) A plastic sheet according to claim 9, which is a sheet formed by curing a composition containing 0.1 to 20 parts by weight of at least one mercapto compound selected from the group consisting of an active energy ray. Laminate. Embedded image [In the formula (3), a plurality of R ⁷ may be different from each other, and each represents a methylene group or an ethylene group. R ⁸ represents a hydrocarbon residue having 2 to 15 carbon atoms which may contain an oxygen atom and / or a sulfur atom in the carbon chain. d shows the integer of 2-6. ] [In the formula (4), Y may be different from each other, and HS- (C
_{H 2) e - (CO)} (OCH 2 -CH 2) f - (C
H ₂ ) _g −. Where e is an integer of 1 to 4, f is 1 to 4
And g represents an integer of 0 to 2, respectively. ] [In the formula (5), R ⁹ and R ¹⁰ may be different from each other and represent a hydrocarbon group having 1 to 3 carbon atoms. m and n each represent 0 or 1. p represents 1 or 2. ] 11. The plastic laminate according to claim 1, wherein the gas barrier film is made of an inorganic oxide. 12. The plastic laminate according to claim 1, wherein the gas barrier film is made of silicon oxide. 13. The plastic laminate according to claim 2, wherein the conductive film is made of indium tin oxide. 14. A substrate for a liquid crystal display device comprising the plastic laminate according to claim 1.