JP2002302539A - Resin substrate for liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin substrate for liquid crystal display elements excellent in heat resistance exhibiting >=200 deg.C glass transition temperature, transparency, solvent resistance, resistance to orientating agents and resistance to liquid crystal. SOLUTION: This resin substrate for liquid crystal display elements is characterized by using a plastic sheet containing a polyester resin represented by the general formula (1) (wherein R represents a 2-7C aliphatic or alicyclic alkylene group; R1 , R2 , R3 , R4 each represent a 1-7C alkyl group, aralkyl group or alkoxy group which may each be same or different) and having a least >=200 deg.C glass transition temperature and 8,000 to 200,000 molecular weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin substrate for a liquid crystal display device, and more particularly, to a thin film transistor (hereinafter referred to as a thin film transistor) having heat resistance of 200.degree. C. or more, excellent in transparency, solvent resistance and liquid crystal resistance. The present invention relates to a resin substrate for a liquid crystal display element suitable for a display element (referred to as TFT).

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices have become thinner, lighter,
There is a high demand for large size, arbitrary shape, and curved surface display. In particular, portable equipment is strongly required to be lightweight and highly durable, and as their use is expanded, a liquid crystal display panel using a plastic substrate instead of a conventional glass substrate has been studied, and some have been put into practical use. I started. However, recently, high-speed responsiveness has been required with the development of color moving images of liquid crystal, and the demand for TFT is increasing.
A glass substrate is still used as a liquid crystal display substrate for TFT, and plasticization is desired in view of strong demands for weight reduction and high durability. JP-A-9-153767 and JP-A-10-15 as resin substrates for liquid crystal display elements
No. 38 is disclosed. However, the glass transition temperatures of the resins exemplified in these patents are 200
° C or lower and CVD (Chemical Vapou).
TFT that goes through a high temperature process such as r Deposition
Warpage and deformation may occur in the element manufacturing process.
Further, in the TFT element manufacturing process, for example, TN, S
Unlike the TN device manufacturing process, it needs to have resistance to dimethyl sulfoxide (DMSO) used for removing the resist and a developing solution for photolithography, and also needs resistance to the liquid crystal mixture itself used for the display device. It is said. An example in which a specific fluorinated polyimide having high heat resistance is used for a liquid crystal display resin substrate (Japanese Patent Laid-Open No.
However, it is not practical to use it for actual production because the raw materials used are very expensive.

[0003]

The problem to be solved by the present invention is to improve heat resistance, transparency, solvent resistance and liquid crystal resistance at a glass transition temperature of 200 ° C. or higher, which can be applied to a TFT liquid crystal display element substrate and the like. An object of the present invention is to provide an excellent resin substrate for a liquid crystal display element.

[0004]

That is, the present invention provides: (1) The following general formula (1) having a glass transition temperature of at least 200 ° C. and a molecular weight of 8,000 to 200,000:
A resin substrate for a liquid crystal display element, comprising using a plastic sheet containing a polyester resin represented by the formula:

[0005]

Embedded image (R represents an aliphatic or alicyclic alkylene group having 2 to 7 carbon atoms, and R1, R2, R3, and R4 represent hydrogen or an alkyl group, an aralkyl group, or an alkoxy group having 1 to 7 carbon atoms. (2) The resin substrate for a liquid crystal display element according to (1), wherein the plastic sheet is not corroded even when heated in dimethylsulfoxide (DMSO) at 40 ° C. for 1 hour. (3) The plastic sheet is (a) the general formula (1)
The resin substrate for a liquid crystal display element according to (2), comprising 99 to 1 parts by weight of a polyester resin represented by the formula (1) and (b) 1 to 99 parts by weight of a polyfunctional monomer having two or more unsaturated groups. (4) The unsaturated group of the polyfunctional monomer (b) having two or more unsaturated groups is an allyl group, a vinyl group, an acryl group,
The resin substrate for a liquid crystal display element according to (3), wherein the resin substrate is at least one selected from methacryl groups. (5) The resin substrate for a liquid crystal display device according to (3) or (4), wherein the compound (b) having two or more unsaturated groups is dicyclopentadienyl diacrylate. (6) The resin substrate for a liquid crystal display element according to any one of (2) to (5), which has been crosslinked by one or more crosslinking methods selected from organic peroxides, electron beams, and ultraviolet rays. It is.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The resin substrate for a liquid crystal display element of the present invention is characterized by using a plastic sheet containing a polyester resin having a glass transition temperature of 200 ° C. or higher. An aromatic polyester obtained by interfacial polycondensation or melt polycondensation of bisphenol and an aliphatic or alicyclic dicarboxylic acid derivative. The bisphenol used for the polyester resin of the present invention has the general formula (2)

[0007]

Embedded image

(Wherein, R1, R2, R3, and R4 are the same as described above). Here, various bisphenols can be applied as the bisphenol represented by the general formula (2). Specific examples include 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9-bis (4-hydroxy-3,5 -Dimethylphenyl) fluorene, 9,9-bis (4-hydroxy-3-ethylphenyl) fluorene, and the like, but are not limited thereto. Among these, 9,9-bis (4-hydroxyphenyl) fluorene is particularly preferred. These bisphenols may be used alone,
Two or more kinds may be used in combination depending on the purpose. Still further, as long as the constitution of the present invention is satisfied, these bisphenols exemplified above and, for example, bis (4-hydroxyphenyl) methane [commonly known as bisphenol F],
1,1-bis (4-hydroxyphenyl) ethane, 2,
2-bis (4-hydroxyphenyl) propane [commonly known as bisphenol A], 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4-dihydroxydiphenyl ether, 4,4-dihydroxydiphenyl sulfone [commonly known as bisphenol S], It may be copolymerized with bisphenols such as 4,4-dihydroxydiphenyl sulfide and 4,4-dihydroxybiphenol.

The polyester resin of the present invention may have a structure containing an unsaturated group, and can be crosslinked by containing an unsaturated group. Examples of the polyester resin containing an unsaturated group include those having an unsaturated group added to the terminal and those copolymerized with bisphenol containing an unsaturated group. Examples of the terminal unsaturated group include an allyl group, an acryl group, a methacryl group, and a maleimide group. Examples of bisphenols containing an unsaturated group include bis (3-allyl-4-hydroxyphenyl) methane (commonly called diallylbisphenol F), 1,1-bis (3-allyl-4-hydroxyphenyl) ethane, 2,2- Bis (3-allyl-4-hydroxyphenyl) propane (commonly called diallylbisphenol A), bis (3-allyl-4)
-Hydroxyphenyl) ether, bis (3-allyl-
Examples thereof include 4-hydroxyphenyl) sulfone (commonly called diallylbisphenol S), bis (3-allyl-4-hydroxyphenyl) sulfide, 3,3-diallyl-4, and 4-hydroxybiphenol. is not.

The aliphatic or alicyclic dicarboxylic acid derivatives used in the present invention include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, methylmalonic acid, ethylmalonic acid and the like. Aliphatic dicarboxylic acids, monocyclic alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, decalin dicarboxylic acid,
Polycyclic alicyclic dicarboxylic acids such as norbornane dicarboxylic acid, adamantane dicarboxylic acid, and tricyclodecene dicarboxylic acid are used. The total amount of the dicarboxylic acid component can be arbitrarily included in the range of 1 to 100 mol%, where 100 is the total.

For the purpose of further improving heat resistance, an aromatic dicarboxylic acid component such as a polycyclic aromatic dicarboxylic acid or biphenyldicarboxylic acid can be used together. At this time, the content of the aliphatic or alicyclic dicarboxylic acid component is desirably 50 mol% or more so as not to deteriorate the optical anisotropy. Examples of the aromatic dicarboxylic acid component used in this case include aromatic monocyclic dicarboxylic acids such as terephthalic acid and isophthalic acid, and polycyclic aromatic dicarboxylic acids such as naphthalenedicarboxylic acid, anthracene dicarboxylic acid, and phenanthylene dicarboxylic acid. And biphenyldicarboxylic acids such as 2,2'-biphenyldicarboxylic acid. However, it is not limited to these. These dicarboxylic acid derivatives may be used alone or in combination of two or more as needed.

The aromatic polyester resin of the present invention can be produced by a known method used for producing an aromatic polyester resin. For example, it can be produced by a so-called interfacial polymerization method in which an alkaline aqueous solution of bisphenol and an aliphatic or aromatic dicarboxylic acid chloride dissolved in an organic solvent incompatible with water are mixed and synthesized.
It can also be produced by a melt polymerization method in which a phenyl ester of an aromatic dicarboxylic acid and bisphenol are heated. However, in the case of the melt polymerization method, it is necessary to heat to a high temperature, and there is a problem that the polymer is easily colored. In the case of production by an interfacial polymerization method, for example, a sodium hydroxide mixed aqueous solution of bisphenol is added to a methylene chloride solution of isophthalic acid dichloride and terephthalic acid dichloride,
It is obtained by polymerizing for 5 minutes to 5 hours with stirring at 5 to 25 ° C.

Examples of the organic solvent incompatible with water include methylene chloride, chloroform, 1,2-dichloroethane,
Chlorobenzene, xylene and the like are used. As the alkaline aqueous solution, an aqueous solution of potassium hydroxide, pyridine or the like is used in addition to sodium hydroxide. In the polymerization reaction, a phase transfer catalyst such as a tertiary amine or a quaternary ammonium salt, for example, triethylamine, benzyltriethylammonium chloride, tetrabutylammonium bromide or the like can be used to activate the polymerization reaction. Also, in order to obtain a polymer of a predetermined molecular weight,
The molecular weight may be adjusted using a molecular weight modifier. As the molecular weight regulator, a monovalent phenol compound is used. For example, p-tert-butylphenol can be used.

The glass transition temperature of the polyester resin of the present invention is preferably 200 ° C. or higher, more preferably 220 ° C. or higher. When the glass transition temperature of the resin is 200 ° C. or lower, warpage or deformation may occur in the TFT element manufacturing process. The number average molecular weight of the polyester resin of the present invention is from 8,000 to 200,000, more preferably from 10,000 to 150,000, and most preferably from 15,000 to 100,000. If the number average molecular weight is 8,000 or less, the polymer tends to be brittle, and if it exceeds 200,000, the viscosity tends to be too high and moldability tends to be poor.

The resin substrate for a liquid crystal display device of the present invention needs to have resistance to dimethyl sulfoxide (DMSO). Methods for imparting resistance to DMSO are as follows: 1. A resin having excellent chemical resistance is coated on a plastic sheet. 2. Crosslink the polyester resin having a crosslinkable functional group. 3. Crosslink by blending a crosslinkable polyfunctional monomer with the polyester resin. And the like. Among them, a method of blending and cross-linking a polyfunctional monomer to impart sufficient chemical resistance is preferable.

As the polyfunctional monomer (b) having two or more unsaturated groups used in the present invention, various compounds having two or more unsaturated groups can be applied. As the unsaturated group, an allyl group, a vinyl group, an acryl group, a methacryl group and the like are preferable. Specific examples of the polyfunctional monomer having two or more unsaturated groups used in the present invention, such as polyallyl compounds such as triallyl isocyanurate, diallyl isophthalate, diallyl terephthalate, divinyl biphenyl, divinyl benzene, trivinyl cyclohexane, etc. Polyfunctional vinyl compound, isocyanuric acid triacrylate, isocyanuric acid triethoxy triacrylate, trimethylolpropane triacrylate, trimethylolpropane triethoxy triacrylate, trimethylolpropane tripropoxy triacrylate, glyceryl propoxy triacrylate, pentaerythritol triacrylate, penta Erythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol pen Acrylate, alkoxy Ray Ted bisphenol A diacrylate, propoxy Ray Ted bisphenol A diacrylate, alkoxy Ray Ted hydrogenated bisphenol A diacrylate,
Propoxylated hydrogenated bisphenol A diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, neopentyl glycol diacrylate, neopentyl glycol dialkoxy diacrylate, dicyclopentadienyl diacrylate, hydrogenated dicyclopentadienyl diacrylate Examples thereof include, but are not limited to, polyfunctional acrylate compounds such as acrylates, and polyfunctional methacrylate compounds in which the acryl group of the polyfunctional acrylate compound is replaced with a methacryl group. Of these, dicyclopentadienyl diacrylate is particularly preferred.

The ratio between the polyester resin (a) used in the present invention and the polyfunctional monomer (b) having two or more unsaturated groups is 99/1 to 1 / (b) by weight% of (a) / (b). 99
Is preferable, 98/2 to 10/90 is more preferable, and 95/5 to 50/50 is particularly preferable. (A)
If the ratio is less than 1% by weight, the crosslinked product tends to become brittle. If it exceeds 99% by weight, the effect of adding (b) is not recognized, and the solvent resistance may be insufficient. The method for crosslinking a resin substrate for a liquid crystal display element of the present invention can be applied by any method as long as it can be polymerized by the reaction of an unsaturated group. Among them, from the viewpoint of transparency, organic peroxides, electron beams, and ultraviolet rays are preferred, and crosslinking using ultraviolet rays is particularly preferred.

The resin substrate for a liquid crystal display element of the present invention becomes a member having excellent solvent resistance by being crosslinked with an organic peroxide, an electron beam, ultraviolet rays, or the like. The method for forming the member can be selected according to the viscosity of the composition comprising the polyester resin (a) and the polyfunctional monomer (b) having two or more unsaturated groups. For example, casting a resin composition dissolved in a solvent, after evaporating the solvent, electron beam or ultraviolet irradiation, or crosslinking and molding by heating, or directly cast on a roll or belt,
Furthermore, using two opposing flat plates that can transmit an electron beam or ultraviolet light made of polished glass or the like, a cavity is formed by a spacer or the like, and injected into an injection mold having a peripheral portion sealed, and the electron beam or It can be molded by cross-linking by ultraviolet irradiation or heating. Alternatively, after the resin composition is extruded, the resin composition may be cross-linked by electron beam, ultraviolet light, or heating to be molded.

(Crosslinking of Organic Peroxide) Crosslinking with an organic peroxide can be carried out by a usual crosslinking method with an organic peroxide applied to unsaturated polyester or the like. As the organic peroxide used in the present invention, known organic peroxides such as dialkyl peroxide, acyl peroxide, hydroperoxide, ketone peroxide, and peroxyester can be used. Specifically, dicumyl peroxide, α, α′-bis (t-butylperoxy) diisopropylbenzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane,
2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, di-t-hexyl peroxide,
1,1-bis (t-butylperoxy) -3,3,5-
Trimethylcyclohexane, t-butylperoxy-2
-Ethylhexanoate, t-butylperoxyisopropyl monocarbonate and the like. The compounding amount of the organic peroxide is preferably from 0.1 to 10 parts by weight, more preferably from 0.5 to 5 parts by weight, based on 100 parts by weight of (a) + (b). If the amount of the organic peroxide is less than 0.1 part by weight, sufficient crosslinking cannot be obtained and the solvent resistance tends to be poor. If the amount is more than 10 parts by weight, the appearance of the crosslinked product tends to deteriorate.

(Crosslinking by Electron Beam) The resin substrate for a liquid crystal display element of the present invention can be crosslinked by radiation such as an electron beam. The irradiation amount of the electron beam is 100 kGy to 2000 kG.
The range of y is preferable, and the range of 500 kGy to 1500 kGy is more preferable, but there is no particular problem even if the value deviates from this range as long as the properties of the obtained crosslinked product do not deviate from the intended range. As the radiation, electron beams from various electron beam accelerators are preferable, but radiation such as α-rays, β-rays, and γ-rays from radioisotopes can also be used.

(Crosslinking by Ultraviolet Ray) The resin substrate for a liquid crystal display element of the present invention can be crosslinked by an ultraviolet ray by adding a photopolymerization initiator. Examples of the photopolymerization initiator include benzophenone, benzoin methyl ether, benzoin methyl ether, benzoin isopropyl ether, diethoxyacetophenone, 1-hydroxycyclohexylphenyl ketone, 2,6-dimethylbenzoyldiphenylphosphine oxide, and 2,4,6-trimethyl. Benzoyldiphenylphosphine oxide and the like. Two or more of these photopolymerization initiators may be used in combination. The addition amount of the photopolymerization initiator is 100% of (a) + (b).
The amount is preferably 0.02 to 5 parts by weight, more preferably 0.02 to 5 parts by weight.
The amount is more preferably from 0.5 to 1 part by weight. If the amount of the photopolymerization initiator is less than 0.02 parts by weight, the crosslinking tends to be insufficient. The irradiation amount of the ultraviolet ray is arbitrary as long as the photopolymerization initiator generates radicals, but it is preferable to irradiate the ultraviolet light in the range of 0.1 to 200 J in accordance with the type and amount of the photopolymerization initiator.

In the present invention, for the purpose of promptly completing the crosslinking, irradiation with an electron beam or ultraviolet rays and thermal polymerization may be used in combination. That is, the composition is heated to 30 to 300 ° C. simultaneously with or after the irradiation with the electron beam or ultraviolet light. in this case,
An organic peroxide may be added. In the present invention, the completion of the polymerization reaction and the internal strain generated during the polymerization can be reduced by heating the crosslinked product after the crosslinking by irradiation with an electron beam or ultraviolet rays. The heating temperature is preferably selected as appropriate according to the composition of the crosslinked product and the glass transition temperature. In order to improve the thermal stability, weather resistance, durability, water resistance, corrosion resistance, and the like, the resin substrate for a liquid crystal display element of the present invention includes, in addition to the components described above, an ultraviolet absorber, a light stabilizer, and an antioxidant. Additives such as an agent, an antifoaming agent, a leveling agent, a release agent, and an ion scavenger can be added to further improve the performance.

[0023]

The present invention will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples. Synthesis Example [Synthesis of polyester resin]
In 163.2 ml of a 1 M aqueous sodium hydroxide solution, 28.0 g of bisphenolfluorene and 0.48 g of benzyltetraethylammonium chloride were dissolved, and 11.8 g of succinic chloride and 160 m of methylene chloride were added thereto.
The solution dissolved in 1 was added and stirred vigorously at room temperature for 30 minutes. After the reaction is completed, the organic phase is separated, washed with water,
Poured into acetone. The precipitate was filtered, washed with acetone and dried. As a result, the number average molecular weight was 20,000
0 polyester resin was obtained.

Example 1 5 g of a synthesized polyester resin and 5 g of cyclopentadienyl diacrylate (DCPDA) were added to chloroform 1
0 g, and 0.05 g of 1-hydroxycyclohexyl phenyl ketone [“Irgacure 184” manufactured by Ciba Geigy] was dissolved therein as a photopolymerization initiator.
This solution was cast on a release-treated glass plate,
After cross-linking by irradiating ultraviolet rays of 00 mJ / cm ² , the sheet was further heated under reduced pressure in a nitrogen oven at 250 ° C. * 1 hour to obtain a sheet having a thickness of 0.2 mm.

Example 2 A sheet was obtained in the same manner as in Example 1 except that 8 g of the synthesized polyester resin and 2 g of dicyclopentadienyl diacrylate (DCPDA) were used. Example 3 A solution prepared by dissolving 8 g of a synthesized polyester resin and 2 g of divinyl biphenyl (DVBP) in 20 g of chloroform was cast on a glass plate subjected to a mold release treatment, and 1000 kG.
After irradiating with electron beam of y to crosslink, it was further heated in a reduced pressure oven at 250 ° C. * 1 hour under reduced pressure for a thickness of 0.2 m.
m of sheets were obtained. Example 4 8 g of the synthesized polyester resin and 2 g of divinyl biphenyl (DVBP) were dissolved in 20 g of chloroform, and bis (t-butylperoxy) as an organic peroxide was dissolved therein.
After dissolving 0.2 g of diisopropylbenzene [“Perbutyl P” manufactured by NOF CORPORATION], this solution is cast on a glass plate subjected to a mold release treatment, and is heated at 150 ° C. * 1 hour + 175 in an oven under a nitrogen atmosphere. ° C * 1 hour + 200 ° C *
After heating for 1 hour for cross-linking, the sheet was further heated under reduced pressure in an oven under reduced pressure at 250 ° C. * 1 hour to obtain a sheet having a thickness of 0.2 mm.

Comparative Example 1 A solution prepared by dissolving 10 g of polyarylate (produced by Unitika Ltd.) in 10 g of chloroform was cast on a release-treated glass plate and dried by heating at 100 ° C. for 1 hour in an oven under a nitrogen atmosphere. After that, further in an oven under reduced pressure for 18
Heating was carried out under reduced pressure at 0 ° C. * 1 hour to obtain a sheet having a thickness of 0.2 mm. Comparative Example 2 5 g of a polyarylate manufactured by Unitika Ltd. and 5 g of dicyclopentadienyl diacrylate (DCPDA) were dissolved in 10 g of chloroform, and 1 g of a photopolymerization initiator was dissolved therein.
After dissolving 0.05 g of -hydroxycyclohexyl phenyl ketone [“Irgacure 184” manufactured by Ciba Geigy], this solution was cast on a glass plate that had been subjected to a mold release treatment, and irradiated with 1,000 mJ / cm ² ultraviolet rays to be crosslinked. Thereafter, the sheet was further heated under reduced pressure in a nitrogen oven at 180 ° C. * 1 hour to obtain a sheet having a thickness of 0.2 mm. With respect to the sheet prepared as described above, deformation such as color, light transmittance, solvent resistance (DMSO), alignment agent resistance, liquid crystal resistance, heat resistance (Tg), warpage, and bending is performed by the following methods. evaluated.

<Evaluation Method> Color: The appearance was visually observed. Light transmittance: The light transmittance at 550 nm was measured with a U3200 type spectrophotometer manufactured by Hitachi, Ltd. DMSO resistance: Dimethyl sulfoxide (DM at 40 ° C)
After immersing the sample in SO) and leaving it to stand for 60 minutes, the sample was taken out and its appearance was visually observed. Alignment agent resistance: A sample is placed on a spin coater. After dripping CRD-8201 (manufactured by Sumitomo Bakelite) on the surface, spin coating was performed at 2500 rpm. 180
After drying at 60 ° C. for 60 minutes, the appearance was visually observed. Liquid crystal resistance: ZIL-47 manufactured by Merck on the surface of the sheet
One drop of 92 was left and left for 1 hour in an oven at 120 ° C., after which the sample was taken out and the appearance was visually observed. Heat resistance (Tg): DMS-2 manufactured by Seiko Denshi Co., Ltd.
The maximum value of tan δ at 1 Hz using a type 10 viscoelasticity measuring apparatus was defined as a glass transition point (Tg). Deformation such as warping and bending: aluminum is formed on a substrate to a thickness of 3000 mm by sputtering, and a simulated wiring pattern having a width of 3 μm and a length of 30 mm is formed by a photolithographic method. Was sputtered to form a 5 mm square resistance measuring electrode. Subsequently, a metal mask having an opening of 10 mm □ is provided at the center of the wiring pattern, and SiN (2000 °) / amorphous Si (500
Å) / SiN (2000 Å) layers were formed by continuous CVD. Furthermore, after putting in a 180 degreeC oven for 1 hour and returning to normal temperature, the external appearance was observed visually.

The evaluation results are shown in Tables 1 and 2. As is clear from these results, Examples 1 to 4 have improved heat resistance, solvent resistance, and alignment agent resistance, which are disadvantages of the conventional polyarylate, and have heat resistance of Tg of 200 ° C. or higher, T having a light transmittance of 90% or more and having transparency and liquid crystal resistance
A sheet suitable for a resin substrate for an FT liquid crystal display element can be obtained.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

The resin substrate for a liquid crystal display element of the present invention is excellent in heat resistance, transparency, solvent resistance, alignment agent resistance and liquid crystal resistance having a glass transition temperature of 200 ° C. or more. It can be suitably used for a resin substrate for liquid crystal display.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // C08L 67:02 C08L 67:02 F term (reference) 2H090 JB03 JD08 JD13 JD17 4F071 AA33X AA44 AA77 AA81 AA86 AF02 AG05 AH16 BC01 4J011 PA88 PC02 PC08 QA12 RA07 SA16 SA22 SA34 SA84 UA01 UA03 VA02 WA07 4J026 AB08 AC23 BA28 DB02 DB09 DB15 DB32 DB36 GA08 4J029 AA03 AB01 AC05 AD01 AE01 BB12A BB13A BC07A03 CA03 JB03CA03 CDB JC091 KE11

Claims (6)

[Claims] 1. A resin substrate for a liquid crystal display element, comprising using a plastic sheet containing a polyester resin represented by the following general formula (1) having a glass transition temperature of at least 200 ° C. and a molecular weight of 8,000 to 200,000. Embedded image (R represents an aliphatic or alicyclic alkylene group having 2 to 7 carbon atoms, and R1, R2, R3, and R4 represent hydrogen or an alkyl group, an aralkyl group, or an alkoxy group having 1 to 7 carbon atoms. It may be the same or different.) 2. The resin substrate for a liquid crystal display device according to claim 1, wherein the plastic sheet is not eroded even when heated in dimethyl sulfoxide (DMSO) at 40 ° C. for 1 hour. 3. A plastic sheet comprising: (a) 99 to 1 part by weight of a polyester resin represented by the general formula (1);
(B) Polyfunctional monomers 1 to 9 having two or more unsaturated groups
3. The resin substrate for a liquid crystal display element according to claim 2, comprising 9 parts by weight. 4. The polyfunctional monomer (b) having two or more unsaturated groups, wherein the unsaturated group is at least one selected from an allyl group, a vinyl group, an acryl group and a methacryl group. 3. The resin substrate for a liquid crystal display element according to 3. 5. Compound (b) having two or more unsaturated groups
5. The resin substrate for a liquid crystal display device according to claim 3, wherein is a dicyclopentadienyl diacrylate. 6. The cross-linking treatment by one or more cross-linking methods selected from organic peroxides, electron beams and ultraviolet rays.
The resin substrate for a liquid crystal display element according to any one of the above.