JP2003033991A - Plastic substrate for display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastic substrate for a display element which is excellent in heat resistance, chemical resistance and steam barrier properties, low in average coefficient of linear expansion and is furthermore high in bending strength, and by which bending, deformation, or cracks due to wiring in a thin-film device forming process are hard to be generated. SOLUTION: The plastic substrate for a display element comprises at least, as constituent element, laminated sheet layers which contain paper or fabric cloth and in which its thickness is 50 to 1000 μm, and the average coefficient of linear expansion in a face direction from a normal temperature to the glass transition point is -5 to 30 ppm/ deg.C, a metal layer, and a resin layer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a reflection type thin film transistor (T) having excellent heat resistance, chemical resistance and dimensional stability.
FT) display device, organic electroluminescence (E
L) Display element, plasma display panel (PD
P), a plastic substrate for a display device suitable for a display device such as a field emission display (FED).

[0002]

2. Description of the Related Art In recent years, there has been a high demand for display elements such as thin film, light weight, large size, arbitrary shape, and curved surface display. In particular, mobile devices are strongly required to be lightweight and highly durable, and as their use expands, display panels that use plastic as a substrate instead of the conventional glass substrate are being considered and have begun to be put into practical use. It was However, recently, the demand for high-speed response has been increasing with the development of color moving images on the display, and the demand for TFTs, organic ELs, etc. is increasing. However, glass substrates are still used for these display substrates, making them lightweight. Due to strong demands for high efficiency and high durability, plasticization is desired. However, the conventional plastic display element substrate has insufficient heat resistance, and there is a risk of warping or deformation in the step of forming a metal semiconductor or an insulating film by CVD (Chemical Vapor Deposition). In addition, since the difference in the coefficient of thermal expansion between the resin layer forming the substrate and the electrode is large, the transparent electrode is likely to crack and the resistance value tends to increase, especially in the application of the TFT liquid crystal substrate which is exposed to a high temperature change during processing. Occasionally, there are cases where it will occur, and sometimes it will fall into a situation such as a disconnection, so it has not yet been put to practical use. On the other hand, reflective liquid crystal display elements have been attracting attention from the viewpoint of low power consumption, and attempts have been made to make plastic for these substrates. For example, Japanese Patent Application Laid-Open No. 11-2812 discloses that a laminated plate including a fiber cloth impregnated with a resin such as a glass epoxy laminated plate is used as a reflective liquid crystal display substrate. However, the reflective conductive substrate exemplified here uses a white pigment for the reflective layer, and is not suitable for the recent demand for high definition and high contrast, and also has a higher barrier for polysilazane. In recent years when dimensional stability is required, it was insufficient in terms of water vapor barrier property.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides heat resistance,
A plastic substrate for a display element, which is excellent in chemical resistance and water vapor barrier properties, has a low average linear expansion coefficient, high bending strength, and is unlikely to cause warpage, deformation, or wiring cracks in the thin film device formation process. Is to provide.

[0004]

[Means for Solving the Problems] That is, the present invention includes (1) a paper or a fiber cloth having a thickness of 50 to 1000 μm.
A plastic plate for a display element, which has m and has a plane direction average linear expansion coefficient from room temperature to a glass transition point of −5 to 30 ppm / ° C., and a metal layer and a resin layer as at least the components. (2) The plastic substrate for a display element according to (1), wherein the laminated plate layer is formed by heat-molding a prepreg obtained by impregnating and drying a paper or fiber cloth with a resin composition containing at least an epoxy resin. (3) The plastic substrate for a display element according to (1), wherein the laminated plate layer is formed by heat-molding a prepreg obtained by impregnating and drying a paper or fiber cloth with a resin composition containing at least a phenol resin. (4) The plastic substrate for a display element according to (1), wherein the laminated plate layer is formed by heat-molding a prepreg obtained by impregnating and drying a resin composition containing at least a polyimide resin into paper or a fiber cloth. (5) The plastic substrate for a display device according to (1) to (4), wherein the metal layer contains at least copper. (6) The plastic substrate for a display element according to (1) to (4), wherein the metal layer contains at least iron. (7) The plastic substrate for a display device according to any one of (1) to (4), wherein the metal layer contains at least aluminum. (8) The resin layer has a Tg of 150 ° C. or higher and has dimethyl sulfoxide resistance, tetramethylammonium hydroxide resistance, and liquid crystal resistance (1) to
(7) A plastic substrate for a display device. (9) The plastic substrate for a display element according to (1) to (8), wherein the resin layer contains at least a cyanate resin. (10) The plastic substrate for a display device according to (9), wherein the cyanate resin is a novolac type cyanate resin and / or a prepolymer thereof. (11) The plastic substrate for a display device according to (1) to (8), wherein the resin layer contains at least a polyfunctional acrylic resin. (12) The plastic substrate for a display element according to (1) to (8), wherein the resin layer contains at least an epoxy resin. (13) The resin substrate for a display element according to (12), wherein the epoxy resin is an alicyclic epoxy resin. (14) The alicyclic epoxy resin is an alicyclic epoxy resin represented by the general formula (1) (1
3) Resin substrate for display element.

[Chemical 2] (15) The plastic substrate for a display device according to (1) to (8), wherein the resin layer contains at least a polyimide resin. (16) The plastic substrate for a display device according to (1) to (15), wherein the metal plate layer also serves as a reflection layer. (17) The plastic substrate for a display device according to (1) to (16), wherein the metal plate layer is laminated adjacent to the laminated plate layer. Is.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION A laminated plate layer containing paper or fiber cloth used in the present invention is a reflection type liquid crystal display substrate which does not use transmitted light, a top emission type organic EL device substrate, and FE.
Since it is used as a D cathode substrate or the like, transparency is not required. The thickness of this laminated plate layer is 50 to 1000 μm, preferably 70 to 700 μm, and more preferably 80 to 500 μm.
μm, and more preferably 100 to 400 μm. Below the lower limit, the rigidity of the board may not be maintained,
If the amount exceeds the upper limit, the weight becomes too large, and there is a risk that the advantages of plasticization for weight reduction may be lost. The average linear thermal expansion coefficient in the plane direction (TMA method, hereinafter the average linear expansion coefficient) from room temperature to the glass transition point of the laminated plate layer is -5 to 30 ppm, preferably 0 to 2
The range is 5 ppm, more preferably 10 to 20 ppm. If the average linear expansion coefficient exceeds the upper and lower limits, the difference with the linear expansion coefficient of the metal used for the wiring becomes large,
May cause wire breakage when exposed to high temperatures.

The laminated plate layer of the present invention has an average linear expansion coefficient of −
It is not particularly limited as long as it has a characteristic of 5 to 30 ppm / ° C., and Tg of the resin used from the viewpoint of heat resistance.
Is preferably 150 ° C. or higher. Specific examples thereof include epoxy resin, phenol resin, and polyimide resin.

The epoxy resin used in the present invention is not particularly limited as long as the laminated plate layer satisfies the above average linear expansion coefficient, and bisphenol A type, novolac type, cyclic fat type and long chain fat type are used alone. Alternatively, two or more kinds can be used in combination. The epoxy curing agent is also not particularly limited, but examples thereof include aromatic polyamines, novolac type phenol resins, imidazole compounds, dicyandiamide, and the like. Above all, it is preferable to include a polyfunctional epoxy resin such as a novolac-based epoxy resin as a constituent because it has high heat resistance and a low linear expansion coefficient. The phenol resin used in the present invention is not particularly limited as long as the laminated plate layer satisfies the above average linear expansion coefficient, such as novolac type and resol type. Further, these may be used in combination. In order to impart flexibility, oil, an epoxy resin, and a thermoplastic resin can be used in combination. Further, in order to impart heat resistance, a resol type phenol resin modified with a drying oil such as tung oil is preferable. The polyimide resin used in the present invention is not particularly limited as long as the laminated plate layer satisfies the above average linear expansion coefficient similarly to the above resin, but a polyimide amide resin, a thermoplastic polyimide resin such as a polyether imide resin, An addition type polyimide resin such as polybismaleimide or a condensation type polyimide resin such as an aromatic polyimide can be used. Among them, thermoplastic polyimide resin and addition type polyimide resin are preferable.

The resin composition used for the laminate layer of the present invention can be used alone or in combination with other thermosetting resins, alkyd resins,
One or more kinds of thermoplastic and / or thermosetting resins such as phenoxy resin, solvent-soluble polyimide resin, polyphenylene oxide, and polyether sulfone may be used in combination.

The resin composition used for the laminated plate layer of the present invention may use an inorganic filler together with the resin component. The inorganic filler is added to increase the elastic modulus, reduce the linear expansion coefficient, and reduce the water absorption.
Examples of the inorganic filler include talc, alumina, glass, silica, mica and the like. Of these, fused silica is preferable because it has excellent low thermal expansion. Further, among fused silica, it is preferable to use spherical fused silica having an average particle diameter of 2 μm or less from the viewpoint of improving the filling property. Also,
From the viewpoint of viscosity control, the average particle size is preferably 0.2 μm or more.
In the present invention, the average particle size was measured by a laser diffraction / scattering method using a particle size distribution measuring device LA920 manufactured by Horiba Ltd. The blending amount of the inorganic filler is 100
The amount is preferably 10 to 400 parts by weight, more preferably 40 to 300 parts by weight, based on parts by weight. When the blending amount is within this range, the thermal expansion of the laminated plate layer can be reduced with good workability.

A coupling agent is preferably added to the resin composition used for the laminated plate layer of the present invention. The coupling agent improves the wettability of the interface between the resin and the inorganic filler, thereby uniformly fixing the resin and the filler on the glass cloth, and the effect of improving heat resistance and hygroscopicity is recognized. As the coupling agent, any commonly used one can be used, and among them, one or more selected from epoxysilane coupling agents, titanate coupling agents, aminosilane coupling agents and silicone oil type coupling agents can be used. It is preferable to use a coupling agent in terms of high wettability with the interface of the inorganic filler and improvement in heat resistance. In the present invention, the coupling agent is
The amount is preferably 0.05% by weight or more and 3% by weight or less with respect to the inorganic filler.

The fiber cloth used for the laminated plate layer in the present invention is not particularly limited, and various inorganic or organic fiber cloths can be used. Specific examples thereof include glass cloths such as E glass (non-alkali glass), S glass, D glass, quartz, and high dielectric constant glass, Kevlar (trade name: manufactured by DuPont Toray Kevlar), Technora (trade name: Teijin's), Conex (trade name: Teijin's) representative poly-p-phenylenephthalamide, poly-m-phenylenephthalamide, p-phenylenephthalamide and 3,4'-diphenyletherphthalamide Examples thereof include aromatic polyamide fiber cloths and aramid fiber cloths made of copolymers, aramid fiber cloths, polyester fiber cloths, nylon fiber cloths, polybenzazole fiber cloths, carbon fibers, carbon fiber cloths such as silicon carbide fibers, and the like. Glass cloth is preferable. The weaving method of the woven filament is not particularly limited, and plain weave, Nanako weave,
A woven fabric having a structure such as satin weave and twill weave may be used, and plain weave is preferable. Further, the material is not limited to the woven cloth and may be a non-woven cloth. Although the thickness of the fiber is not particularly limited, it is preferably 30 to 200 μm, more preferably 40 to 100 μm.

The fiber cloth used in the present invention is surface-treated with various silane coupling agents, borane coupling agents, titanate coupling agents, aluminum coupling agents, etc. for the purpose of improving wettability with resin components. It may be treated with an agent, but is not limited thereto. The paper used in the present invention is not particularly limited as long as it impregnates the resin layer, but kraft paper, cotton linter paper, aramid paper and the like can be used.

The resin composition used in the laminated plate layer of the present invention may contain, if necessary, a lubricant, a heat-resistant agent, an antistatic agent, an ultraviolet absorber, a pigment, etc. within a range not impairing the effects of the present invention. Ingredients such as stabilizers may be added. The laminated plate layer of the present invention is obtained by impregnating a paper or fiber cloth with a resin composition and drying it to form a prepreg, and heat-molding one or more of the prepregs. The metal layer of the present invention is not particularly limited, but Ni, Al, Ag, C
u, Cr, Mn, Mg, Zn, C, Si, Mo, V, N
Those containing at least one of b, Ti, Pd, Pt, Au, Fe, Sn, Zn, etc. are preferable, and alloys, oxides thereof,
It may be a nitride or a halide. Further, the surface may be treated by polishing including sandblasting, lapping, buffing, etching, reverse sputtering and the like. The metal layer can be obtained by thermoforming a copper foil and the like when the laminate layer is thermoformed, and can be formed on one side surface or both surfaces of the laminate layer by a method such as vapor deposition, sputtering or thermal spraying. It is also possible to stack the layers on each other, and the stacking method is not particularly limited. Since the metal layer is less likely to allow water vapor to pass therethrough, an effect of suppressing dimensional change due to moisture absorption of the laminated plate layer and the resin layer can be expected. In addition, by laminating the metal layer adjacent to the laminated plate layer, it is possible to obtain a reflective layer that reflects the surface shape of the laminated plate layer to some extent. Suitable reflection characteristics can be obtained in response to the demand for high contrast. To impregnate a paper or fiber cloth with the resin composition of the present invention, alcohols, ethers, acetals, ketones, esters, alcohol esters,
Varnish using organic solvents such as ketone alcohols, ether alcohols, ketone ethers, ketone esters and ester ethers, and apply to paper or fiber cloth.
A prepreg can be obtained by drying.
Also, a prepreg can be obtained by applying the resin composition of the present invention to a paper or a fiber cloth without solvent and drying the composition.

The plastic substrate for a display device of the present invention comprises
A resin layer is preferably provided as the outermost layer in order to impart insulating properties and / or to improve smoothness or reflection characteristics. The resin layer may be formed by coating, but may be formed by lamination or pressing using a film and is not particularly limited. As the material of the resin layer, cyanate resin, polyfunctional acrylic resin, epoxy resin, polyimide resin, etc., Tg of 150 ° C.
As described above, it is preferable that the main component is a resin having excellent chemical resistance. The thickness of the resin layer is preferably 1 to 100 μm, more preferably 2 to 60 μm. Further, for the purpose of imparting insulating properties, the same material as that of the laminated plate layer, that is, a material containing paper or fiber cloth may be used. The cyanate resin used in the resin layer of the present invention includes bisphenol dicyanate, di (4-cyanate-3,5-dimethylphenyl) methane, 4,4′-thiodiphenylcyanate,
2,2′-di (4-cyanatephenyl) hexafluoropropane, bisphenol E dicyanate, phenol / dicyclopentadiene copolymer cyanate, phenol novolac type cyanate resin, cresol novolac type cyanate resin, and / or its prepolymer Can be used. Among them, the novolac type cyanate resin and / or its prepolymer are preferable because of their high heat resistance and low linear expansion coefficient. The novolac type cyanate resin referred to here is obtained by reacting an arbitrary novolac resin with a cyanating reagent such as cyanogen halide, and can be prepolymerized by heating the obtained resin. Then, the resin layer can be obtained by further heating after coating the laminated plate layer or the metal layer. When a cyanate resin is used in the resin layer of the present invention, a curing accelerator can be added to the resin composition.
As the curing accelerator, known ones can be used,
Examples include organic metal salts such as zinc naphthenate, cobalt naphthenate, tin octylate, and cobalt octylate, triethylamine, tributylamine, diazabicyclo.
Tertiary amines such as [2,2,2] octane, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4 Examples include imidazoles such as -methyl-5-hydroxymethylimidazole, phenol compounds such as phenol, bisphenol A, nonylphenol, and phenol novolac resin, organic acids, and the like, or a mixture thereof. Among these, the phenol novolac resin is preferable in terms of curability and small amount of ionic impurities. In the present invention, the compounding amount of the curing accelerator can be appropriately changed depending on the use conditions, but is 0.05% by weight or more and 10% by weight or less based on the novolac type cyanate resin and / or its prepolymer. Is desirable. As the polyfunctional acrylic resin used in the resin layer of the present invention, a polymer obtained by crosslinking a monomer having a bifunctional or more acryloyl group such as isocyanuric acid ethylene oxide-modified triacrylate or dicyclopentadienyl diacrylate is used. preferable. As a method of forming a resin layer using these polyfunctional acrylates, a method of heating can be used as in the case of the cyanate resin, and in that case, it is preferable to add a thermal decomposition type initiator. The thermal decomposition type initiator is not particularly limited, but one selected from the group consisting of an azo type initiator and a peroxide type initiator is preferable. Particularly, a peroxide-based initiator capable of generating radicals under the drying temperature condition is preferable. Examples of this peroxide type initiator include dicumyl peroxide,
Examples thereof include dialkyl peroxides such as di-t-butyl peroxide, peroxyesters such as t-butylperoxypivalate and t-hexylperoxypivalate, among which peroxyesters are preferred. . The thermal initiator used in the present invention may be a catalytically effective amount, and its blending amount is not particularly limited, but is 0.01% with respect to 100 parts by weight of the acryloyl group-containing organic component.
Is preferably about 5 parts by weight, more preferably about 0.02.
5 to 2 parts by weight. A curing method using an energy beam such as an electron beam or a light beam is also possible, and in this case, it is preferable to include a photopolymerization initiator which generates a radical in the composite composition. The photopolymerization initiator used in that case is not particularly limited, for example, benzophenone, benzoin methyl ether, benzoin propyl ether,
Diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,2-dimethoxy-1,
2-diphenylethan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzophenone and the like can be mentioned. Two or more of these photopolymerization initiators may be used in combination. The content of these photopolymerization initiators is preferably 0.01 to 5 parts by weight, more preferably 0.1 to 5 parts by weight, and most preferably 100 parts by weight of the organic component containing an acrylic group. Is
It is 0.3 to 2 parts by weight.

The epoxy resin used in the resin layer of the present invention is not particularly limited, but phosphorus-modified epoxy resin,
An alicyclic epoxy resin, a polyester-modified alicyclic epoxy resin, a dicyclopentadiene-modified epoxy resin, an imide epoxy resin or the like is preferably contained as a main component, and among them, the alicyclic epoxy resin represented by the formula (1) is particularly preferable. It is preferable to use an epoxy resin as a main component. These epoxy resins can also be cured by heat to form a resin layer. Examples of the curing agent include phthalic anhydride, tetraphthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, trimellitic anhydride, polyazelaic anhydride, and other acid anhydride curing agents, ethylenediamine, diethylenetriamine, meta. Amine-based curing agents such as phenylenediamine, phenols novolaks, trisphenolmethane, phenols / dicyclopentadiene polymer, phenols / xylylene glycols polycondensate,
Examples thereof include, but are not limited to, phenols / biphenyldimethanol polycondensates, phenolic curing agents such as bisphenol S, and the like. These may be used alone or in combination of two or more. The polyimide resin used in the resin layer of the present invention is not particularly limited, but the polyimide amide resin used in the laminated plate layer of the present invention, a thermoplastic polyimide such as a polyetherimide resin, or an addition type polyimide such as polybismaleimide. A condensation type polyimide resin such as resin or aromatic polyimide can be used. Among them, condensed polyimides are preferable from the viewpoint of high heat resistance and low linear expansion coefficient. The resins for forming these resin layers may be used alone or in combination of two or more kinds. When it is necessary to smooth the surface of the resin layer, for example, a plate having a high surface smoothness, such as glass or metal, may be placed on the surface and heated, and in order to form the mat layer for improving the reflection characteristics. It is also possible to heat using a jig such as a roll or a belt for transferring the mat shape. Further, when curing the energy rays, a smooth plate or a mat forming jig made of a material such as glass that transmits the energy rays may be used. The plastic substrate for a display device of the present invention may be subjected to a barrier treatment such as moisture resistance and gas permeation resistance, a hard coat treatment, a transparent electrode treatment and the like, if necessary. When the plastic substrate for a display element of the present invention is used for a reflection type display element, a metal layer may be used as a reflection layer, or an electrode layer formed on the substrate of the present invention may be used as a reflection layer. In any case, since the metal layer is used, it is possible to obtain a high-contrast reflection-free reflection layer by appropriately treating the surface of the metal layer or the electrode layer with high reflection efficiency.

[0016]

EXAMPLES Next, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the following Examples unless the gist thereof is exceeded. The types of the metal layer and the resin layer can be combined in any manner, and the type of the display element is not limited. <Example 1> Phenolic resin copper-clad laminate (PLC-2147) obtained by impregnating paper with a phenol resin, stacking a dried prepreg and a 35 μm copper foil, and heat-pressing them.
RH one side, plate thickness 0.8 mm, average linear expansion coefficient of laminated plate layer about 22 ppm / ° C .: Sumitomo Bakelite) on both sides, bisphenol A type epoxy acrylate 65% solution (lipoxy VR-60LAV-1A: Showa High Polymer) 2 1 part by weight, a mixture of DPHA: dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA: Nippon Kayaku) 0.9 part by weight, isocyanuric acid EO-modified triacrylate (Aronix M-31)
5: Toa Gosei) 8.9 parts by weight 2,2-dimethoxy-
1,2-diphenylethan-1-one (IRGACU
RE651: Ciba Specialty Chemicals) 0.2 parts by weight, and a resin varnish consisting of 32.4 parts by weight of butyl acetate / butyl cellosolve (weight ratio 4/1) as a solvent,
UV-cured by the cast casting method to a thickness of about 60μ
The resin layer of was formed. The copper foil surface of PLC-2147RH is roughened by etching, and the resin layer on the laminated board layer side is
The matte layer was formed using a glass plate with controlled unevenness in order to reflect light efficiently. Example 2 A glass cloth is impregnated with an epoxy resin,
Epoxy resin copper clad laminate obtained by stacking a dried prepreg and a 18 μm copper foil and performing heat and pressure molding (EL
C-4765 One side, plate thickness 0.15 mm, copper foil surface of laminated board layer having an average linear expansion coefficient of about 16 ppm / ° C: Sumitomo Bakelite) is roughened by etching, and epoxy prepreg (EI-6765 thickness 0. 1 mm, average linear expansion coefficient of about 16
ppm / ° C .: Sumitomo Bakelite) were layered and heated and pressed. Further, a resin layer having an uneven surface was formed on the laminated layer of ELC-4765 by using dicyclopentadiene diacrylate (Toagosei Co., Ltd.) in the same manner as in Example 1. <Example 3> Epoxy prepreg (EI
-6765 0.2mm thickness, average linear expansion coefficient of laminated board layer about 16ppm / ℃: Sumitomo Bakelite), instead of copper foil, aluminum foil about 8μm thick (PACAL21: foil made in Japan) on one side Heat and pressure molding was performed again. Next, the dicyclopentadiene diacrylate (Toagosei Co., Ltd.) used in Example 2 was cast-cast on the side of the laminated plate, a smooth glass surface was applied, and the resin having a smooth surface was obtained by ultraviolet curing through the glass surface. A layer (about 20 μm) was formed. <Example 4> An epoxy resin double-sided copper-clad laminate obtained by impregnating glass cloth with a heat-resistant epoxy resin, laminating 18 μm copper foil on both surfaces of a dried prepreg, and performing heat-press molding (ELC-4781 plate thickness 0.1 mm, average linear expansion coefficient of laminated plate layer about 15 ppm / ° C: Sumitomo Bakelite) is used to roughen the copper foil surface, and novolac type cyanate resin (PT60 number average molecular weight 800: Lonza Japan) on both surfaces. 100 parts by weight and phenol novolac resin (
A resin layer was formed using a varnish prepared by dissolving 2 parts by weight of PR-51714: Sumitomo Dures) in methyl ethyl ketone at room temperature. It should be noted that one side has a thickness of about 2 μm by coating in order to form a resin layer for the purpose of insulation, and the other side that needs to have a smooth surface for circuit formation uses the cast casting method. By thermosetting with a mirror surface applied, a smooth resin layer having a thickness of about 15 μm was obtained. <Example 5> A prepreg using the same heat-resistant epoxy as in Example 4 (EI-6781, thickness: 0.05 mm, average linear expansion coefficient: about 15 ppm / ° C) was overlaid with stainless steel foil of 40 μm, and heated and pressed. It was manufactured in the same manner as in Example 4 except that molding was performed. <Example 6> A fiber cloth having glass cloth formed on both sides of a glass non-woven fabric was impregnated with an epoxy resin, and a dried prepreg was overlaid with a copper foil of 18 µm on both sides, followed by heat and pressure molding. Epoxy resin double-sided copper clad laminate (ELC-
4970 Plate thickness 0.8mm, average linear expansion coefficient of laminated layers is about 2
4ppm / ℃: Sumitomo Bakelite) copper foil surface is roughened,
In the same manner as in Example 2, a 100 μm dicyclopentadiene diacrylate cured resin layer was formed on both sides.
As one of the resin layers, a resin layer having an uneven surface was formed as in Example 1. <Example 7> A BT resin obtained by impregnating a glass cloth with a BT resin containing bismaleimide and triazine as a main component as a polyimide resin, stacking a dried prepreg and a copper foil, and performing heat-pressing. Double-sided copper clad laminate (CCL-
HL-950 Thickness 0.2mm, average linear expansion coefficient of resin layer is about 1
3 ppm / ° C .: Mitsubishi Gas Chemical Co., Ltd. was sandwiched between two polyimide films (Upilex VT: Ube Industries), and heated and pressure-molded to be integrated. <Example 8> As a polyimide resin on glass cloth,
2,2-bis (4-cyanatophenyl) propane 90
Part and bis (4-maleimidophenyl) methane 10 parts were dissolved in methyl ethyl ketone, and zinc octylate 0.05 parts and triethylenediamine 0.05
The prepreg (thickness: about 0.1 mm) that has been impregnated with a varnish containing parts is sandwiched between two aluminum foil (PACAL21: foil made in Japan) with a thickness of about 8 μm, and heat and pressure molding is performed. And integrated. The average linear expansion coefficient of this laminated plate layer was about 12 ppm / ° C. Next, as the resin layer, 100 parts by weight of alicyclic epoxy (Celoxide 2021P: Daicel) having a structure like the formula (1) (solid content conversion), bisphenol S (development name EX-1 (B):
Daicel) 3 parts by weight, cation catalyst (development name EX-1
(A): 0.5 part by weight of Daicel, a surfactant (F-
177: Dainippon Ink Co., Ltd.), and after immersing in a solution dissolved in 2-butoxyethanol, it was pulled up, precured at 170 ° C. for 30 minutes, and then heat cured at 200 ° C. for 2 hours. Furthermore, using the same resin, Example 4
Similarly to the above, the resin layer having a smooth surface of about 15 μm was formed on one side by heat curing by the cast casting method. <Example 9> 95 parts of bis (4-maleimidophenyl) methane and 5 parts of bis (4-aminophenyl) methane were used as polyimide resin on a carbon fiber cloth (Nicalon: Nippon Carbon) treated with an epoxysilane coupling agent. N,
After pre-reacting in N-dimethylformamide, novolac type epoxy resin (ECN-1273: Ciba Geigy) 10
A prepreg (thickness: about 0.2 mm) that had been impregnated with a varnish mixed with a part was sandwiched between two copper foils having a thickness of about 12 μm, and heat-press molding was performed to integrate them.
The average linear expansion coefficient of this laminated plate layer was about 12 ppm / ° C. After roughening the copper foil surface by etching,
6.37 g of trizine was added to N, N-dimethylacetamide 1
After completely dissolving in 30 mL, 6.54 g of pyromellitic dianhydride was added, and the polyimide varnish obtained by stirring at 15 ° C. for 1 hour and at room temperature for 3 hours was cast on both copper foil surfaces and dried. Then, in an oven under reduced pressure, 150 ° C * 30 minutes + 200 ° C * 30 minutes + 250 ° C * 30 minutes + 300 ° C * 3
It was heated under reduced pressure for an hour to be imidized.

<Comparative Example> A glass epoxy copper clad laminate (TLC551M: Toshiba Chemical) having a thickness of 0.1 mm was subjected to an etching treatment to peel off the copper foil to prepare a laminate made of E glass. Two of these were laminated and heat-pressed and integrated. Next, a heat-resistant white paint (No.4264-2: Okitsumo) was applied on both sides and cured to form a reflective layer. Furthermore, low temperature firing type polysilazane solution (N-L11
(0: Tonen) and then dried, and then immersed in hydrogen peroxide for 4 hours and then dried at 150 ° C. for 2 hours.

<Evaluation 1> The matte layer (concavo-convex surface) of the plastic substrate for a display device of Example 1, Example 2 and Example 6
Sputter aluminum on top to a thickness of 200Å,
A semitransparent reflective surface was formed. Further, on the resin layer of Example 3, SiOx was sputtered to a thickness of 500Å,
Used as a water vapor barrier. A color filter layer was formed on the reflective layer side (Al surface in Example 3) of the plastic substrates of Examples 1 to 3, Example 6 and Comparative Example. The color filter layer is formed on the barrier layer deposition surface side having a water vapor permeability of 0.06 g / m ² / day by photolithography using a resin black matrix material and three types of pigment-dispersed color resists of R, G, and B. went. The size of the R, G, B color resists was 70 μm × 200 μm, and a black matrix was formed between them with a width of 10 μm. The outer size of the black matrix was 40 mm × 60 mm, and the color filter formation range was 30 mm × 50 mm. Further, a color filter overcoat material was applied by a spin coater and cured in an oven at 170 ° C. for 1 hour. As a substrate for forming a color filter to be used in combination, a transparent plastic substrate in which polyether sulfone (PES) was used as a substrate material and a water vapor barrier of SiOx was formed on both surfaces was used. Next, transparent electrodes were formed on both substrates. The substrate on which the color filter was formed had a thickness of indium tin oxide (ITO) of 10 on the surface on which the color filter was formed and on one surface of the PES substrate by a single-wafer sputtering apparatus.
A film having a thickness of 0 nm was formed and patterned into a stripe shape by photolithography and etching to obtain a transparent electrode.
Alignment agent is printed / formed on the patterned transparent electrode,
After rubbing so as to have a twist orientation of 240 degrees, it was washed and dried. Next, the PES substrate was screen-printed with a sealing material and prebaked. Meanwhile, spacers were scattered on the substrate side of the example and the comparative example in which the color filter was formed. In addition, the spacer used had an adhesive coating. Subsequently, the two substrates were bonded together, and the sealing material was completely cured to form a cell.
A composition prepared by adding a chiral agent to ZLI2293 manufactured by Merck Ltd. as a liquid crystal was injected into the cell and sealed with a sealing material to obtain a liquid crystal cell. Further, a retardation film and a polarizing film were attached to the liquid crystal cell to obtain a liquid crystal display device. When a drive waveform generator was connected to the produced liquid crystal display device to perform display, in Example 4, good display performance was obtained in both brightness and contrast, but in Comparative Example, it was evaluated as insufficient contrast. there were.

<Evaluation 2> With respect to the plastic substrates of Examples 4, 5, 7 to 9 and Comparative Example, a gas chromatography vapor permeability measuring instrument GTR- manufactured by Yanaco Analytical Industry Co., Ltd.
30 was used to measure the water vapor permeability. As a result, in the examples having the metal layer, all of the values below the measurement limit were 0.0.
01G / m was ² · day or less, but in the comparative example was 0.3 g / m ² · day. Generally, when a plastic substrate is used for a TFT liquid crystal substrate that requires high definition, the water vapor permeability of the plastic layer is 0.1 g / m ² · da due to the dimensional change tolerance due to water absorption.
It must be less than or equal to y. Further, in the organic EL display element, it is required that the water vapor permeability of the light emitting element is further at least 0.01 g / m ² · day or less. In addition to these, the plastic substrates of Examples 4, 5, and 7 to 9 also exhibited excellent performance in terms of low linear expansion coefficient, solvent resistance, heat resistance, and rigidity. From the above, the present invention is applicable not only to the STN type liquid crystal display element but also to the reflective TF.
T liquid crystal display device, organic EL display device, plasma display panel (PDP), field emission display (FE)
It was found that it is also suitable for display elements such as D).

[0020]

As described in detail above, the plastic substrate for a reflective liquid crystal display device of the present invention has a high degree of water vapor barrier property, heat resistance, chemical resistance, low average linear expansion coefficient, and rigidity. Therefore, it is suitable for various kinds of display devices.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // C08L 87:00 C08L 87:00 F term (reference) 3K007 AB11 AB12 AB13 AB14 CA05 CC01 EB00 4F072 AB09 AB28 AB31 AD13 AD23 AD45 AG03 AG07 AG16 AG20 AH21 AL12 4F100 AB01B AB02B AB10A AB17B AK01C AK25C AK33A AK49A AK49C AK51C AK53A AK53C AL05C BA03 BA10A BA10C DG10A DG11A DH01A EJ82A GB41 JA02A JA05C JN06B YY00A YY00C 5C094 AA33 AA36 AA37 AA38 BA29 BA31 BA43 EA06 EB01

Claims (17)

[Claims] 1. A paper or fiber cloth is contained and has a thickness of 50 to 1.
A laminated board layer having a surface direction average linear expansion coefficient from room temperature to a glass transition point of −5 to 30 ppm / ° C., and a plastic substrate for a display element, which includes at least a metal layer and a resin layer as constituent elements. 2. The plastic substrate for a display element according to claim 1, wherein the laminated plate layer is formed by heat-molding a prepreg obtained by impregnating and drying a paper or fiber cloth with a resin composition containing at least an epoxy resin. 3. The plastic substrate for a display element according to claim 1, wherein the laminated plate layer is formed by heat-molding a prepreg obtained by impregnating a paper or fiber cloth with a resin composition containing at least a phenol resin and drying the prepreg. 4. The plastic substrate for a display device according to claim 1, wherein the laminated plate layer is formed by heat-molding a prepreg obtained by impregnating and drying a paper or fiber cloth with a resin composition containing at least a polyimide resin. 5. The plastic substrate for a display element according to claim 1, wherein the metal layer contains at least copper. 6. The plastic substrate for a display element according to claim 1, wherein the metal layer contains at least iron. 7. The plastic substrate for a display device according to claim 1, wherein the metal layer contains at least aluminum. 8. The resin layer according to claim 1, wherein Tg of the resin layer is 150 ° C. or higher and dimethyl sulfoxide resistance, tetramethylammonium hydroxide resistance, and liquid crystal resistance are provided. Plastic substrate for display element. 9. The plastic substrate for a display device according to claim 1, wherein the resin layer contains at least a cyanate resin. 10. The plastic substrate for a display device according to claim 9, wherein the cyanate resin is a novolac type cyanate resin and / or a prepolymer thereof. 11. The plastic substrate for a display device according to claim 1, wherein the resin layer contains at least a polyfunctional acrylic resin. 12. The plastic substrate for a display device according to claim 1, wherein the resin layer contains at least an epoxy resin. 13. The resin substrate for a display device according to claim 12, wherein the epoxy resin is an alicyclic epoxy resin. 14. The resin substrate for a display device according to claim 13, wherein the alicyclic epoxy resin is the alicyclic epoxy resin represented by the general formula (1). [Chemical 1] 15. The resin layer according to claim 1, wherein the resin layer contains at least a polyimide resin.
A plastic substrate for a display device according to the item. 16. The plastic substrate for a display device according to claim 1, wherein the metal plate layer also serves as a reflective layer. 17. The plastic substrate for a display device according to claim 1, wherein the metal plate layer is laminated adjacent to the laminated plate layer.