JPH11174424A - Substrate for liquid crystal display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a substrate for a liquid crystal display panel excellent in optical characteristics, display quality and heat resistance by using an aromatic polycarbonate resin comprising a repeating unit.expressed by a specified formula as a base. SOLUTION: The substrate for a liquid crystal display panel consists of a base an aromatic polycarbonate resin having a repeating unit expressed by the formula. In the formula, R1 to R8 are independently hydrogen atoms, halogen atoms and 1-6C hydrocarbon groups. The halogen atoms are fluorine, chlorine, bromine atoms or the like. Examples of the 1-6C hydrocarbon groups are methyl group and ethyl group, and X is 1-15C hydrocarbon group and is preferably propylidene group, 1,1-cyclohexylidene group, or 9,9-fluolidene group. However, when R1 to R8 are hydrogen atoms, a bisphenol-A polycarbonate with X being an isopropylidene group is excluded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for a liquid crystal display panel, and more particularly, to a liquid crystal display panel having excellent optical characteristics and excellent display quality by using a substrate made of a polycarbonate resin. The present invention relates to a liquid crystal display panel substrate to be realized.

[0002]

2. Description of the Related Art In recent years, there has been a high demand for liquid crystal display elements such as thinner, lighter, larger, arbitrary shapes, and curved surface display. In particular, as the use of portable devices such as pagers (pagers), cellular phones (cell phones), electronic notebooks, and pen input devices has expanded, liquid crystal panels using plastic substrates instead of conventional glass substrates have been studied, and some have been put into practical use. Began to be.

[0003] Compared to glass substrates, plastic substrates satisfy the demand for weight reduction and thinning, and have the effect of improving the visibility of liquid crystal display panels, but are said to be inferior to glass substrates in optical characteristics. I have no choice. Glass is optically isotropic in nature, but in the case of plastic, there is a problem that retardation occurs due to the correlation between the molecular orientation or residual strain generated during molding of the plastic substrate and the optical elastic coefficient specific to the resin.

The display function of a liquid crystal display is based on the principle of visualizing the display by optical switching of polarized light. Therefore, if the plastic substrate used as the substrate has birefringence, the display quality of the display is remarkably deteriorated, such as coloring of display and lowering of contrast.

[0005] In order to remedy this drawback, a method of improving the optical properties of the resin and a method of casting polymerization with a single sheet (JP-A-5-323303) have been studied.

However, in the conventional studies, a method of significantly reducing productivity such as using a special resin material, setting special production conditions, or molding a sheet for a long time, or using a very special resin material is considered. Because of the method used, it has to be said that this is an improvement proposal without cost competitiveness with respect to a conventionally used glass substrate.

On the other hand, as the definition of liquid crystal displays has been advanced in recent years, heat resistance during processing has been required. Therefore, even for plastic substrates, excellent optical isotropy and high glass transition temperature (Tg)
Are required. In particular, with respect to heat resistance, it has become possible to perform MIM type active matrix liquid crystal and excimer laser annealing of amorphous silicon at a temperature of 180 ° C. or higher, and a resin substrate having higher heat resistance is required.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate for a liquid crystal display panel having excellent heat resistance and realizing a liquid crystal display panel having excellent optical characteristics and excellent display quality.

[0009]

As a result of diligent studies, the present inventors have found a substrate made of polycarbonate which provides a substrate for a liquid crystal display panel having small optical anisotropy, dimensional stability and heat resistance. Was. The substrate for a liquid crystal display panel according to the present invention has not only the same display quality as when a glass substrate is used, but also has mechanical properties higher than those of a glass substrate.

That is, the present invention provides the following formula (1)

[0011]

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[In the above formula (1), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom and a carbon atom having 1 to 6 carbon atoms.
And X is a hydrocarbon group having 1 to 15 carbon atoms. However, when R _{1 to} R ₈ are hydrogen atoms, X is not an isopropylidene group. ] It is a substrate for liquid crystal display panels using an aromatic polycarbonate resin comprising a repeating unit represented by the following formula:

Further, a repeating unit represented by the above formula (1) and the following formula (2)

[0014]

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A liquid crystal based on a copolymerized polycarbonate resin comprising a repeating unit represented by the formula (1), wherein the repeating unit represented by the above formula (1) accounts for 30 to 99 mol% of the whole. This is a display panel substrate.

The substrate for a liquid crystal display panel of the present invention comprises a substrate made of an aromatic polycarbonate resin having a repeating unit represented by the above formula (1). In the above formula (1), R _{1 to} R ₈ are each independently selected from a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. Examples of the hydrocarbon group having 1 to 6 carbon atoms include a methyl group and an ethyl group. X is a hydrocarbon group having 1 to 15 carbon atoms. Preferred examples of such a hydrocarbon group include a propylidene group, a 1,1-cyclohexylidene group, a 3,3,5-trimethyl-1,1-cyclohexylidene group, and a 9,9-fluoridene group.

However, when R _{1 to} R ₈ are hydrogen atoms, X
Is a isopropylidene group, that is, a so-called bisphenol A type polycarbonate is excluded.

As the base material of such a liquid crystal display panel substrate, for example, fluorene-9,9-di (4-phenol) type polycarbonate, fluorene-9,9-di (3
-Methyl-4-phenol) type polycarbonate, 3,
3 ', 5,5'-Tetramethylbisphenol A type polycarbonate, 3,3,5-trimethyl-1,1-di (4-phenol) cyclohexylidene type polycarbonate can be mentioned.

The aromatic polycarbonate resin is a copolymer of a polycarbonate comprising a repeating unit represented by the above formula (1) and a so-called bisphenol A type polycarbonate having a repeating unit represented by the above formula (2). Is also good. Fluorene-9,9-di (4-phenol), fluorene-9,9
-Di (3-methyl-4-phenol) (both corresponding to the following formula (4)), 3,3 ′, 5,5′-tetramethylbisphenol A (corresponding to the following formula (3)), 3,3, 5-Trimethyl-1,1-di (4-phenol) cyclohexylidene (corresponding to the following formula (5)) is preferred.

[0020]

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[In the above formula (3), R _{1 to} R ₈ each independently represent a hydrogen atom, a halogen atom and a carbon atom having 1 to 6 carbon atoms.
Is a hydrocarbon group. However, R _{1 to} R ₈ are not simultaneously hydrogen atoms. ]

[0022]

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[In the above formula (4), R _{1 to} R ₈ each independently represent a hydrogen atom, a halogen atom and a carbon atom having 1 to 6 carbon atoms.
Is a hydrocarbon group. ]

[0024]

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[In the above formula (5), R _{1 to} R ₈ each independently represent a hydrogen atom, a halogen atom or a carbon atom having 1 to 6 carbon atoms.
Is a hydrocarbon group. ]

In this case, the proportion of the repeating unit represented by the above formula (1) is preferably 30 to the entire repeating unit.
９９99 mol%, more preferably 30-75 mol%. If it is less than 30 mol%, the heat resistance may be insufficient.

The degree of polymerization of the polycarbonate resin used as the base material of the substrate for a liquid crystal display panel of the present invention was determined by extrapolating the intrinsic viscosity [η] obtained by measuring and extrapolating a methylene chloride solvent at 20 ° C. using an Ubbelohde viscometer. The value is preferably 0.15 to 1.0. If [η] is less than 0.15,
In some cases, a film or sheet-like molded product having sufficient strength cannot be obtained. If it is larger than 1.0, molding may be difficult. The intrinsic viscosity is more preferably from 0.25 to 0.7.

The method for polymerizing the above polycarbonate resin is not particularly limited, and examples thereof include ordinary interfacial polymerization methods and melt polymerization methods.

The thickness of the substrate constituting the substrate for a liquid crystal display panel of the present invention is preferably 50 to 700 μm. When the thickness is less than 50 μm, there is a problem that handling becomes difficult in the process of manufacturing the base material. When the thickness is more than 700 μm, not only the characteristic of the resin base material that is lightweight is lost, but also the display quality is deteriorated due to an increase in parallax, which is not preferable. The thickness of the substrate is more preferably 70
５００500 μm.

The thickness unevenness is preferably ± 5% or less because it directly affects the unevenness of the cell gap of the liquid crystal cell. Furthermore, since the retardation is represented by the product Δn · d of the refractive index difference Δn between the slow axis and the fast axis and the thickness d of the base material, the base material having less unevenness of the thickness has less variation in the retardation. . Therefore, the thickness unevenness is more preferably ±
It is 2.5% or less.

The above base material has excellent heat resistance, and the glass transition temperature is desirably 160 ° C. or higher. If the temperature is lower than 160 ° C., in the alignment film forming process and the electrode forming process
Restrictions may arise. Further, the glass transition temperature is preferably 180 ° C. or more to withstand the formation of the MIM element.

The retardation value of the substrate is preferably 20
nm or less. If it is larger than 20 nm, coloring or inversion of the display will occur, and the display quality will deteriorate. The value of the retardation is more preferably 10 nm or less, and still more preferably 5 nm or less.

When a dot matrix drive is performed on a large panel such as an STN, it is desired that the maximum refractive index direction indicating the direction of the molecular orientation axis, that is, the dispersion of the slow axis be small. Usually, ± 15 ° or less is preferably used, but ± 10 ° or less is preferably used for fine display. To realize multi-color display with good color reproduction on a large STN panel, a retardation value of 10 nm
Hereinafter, it is particularly preferable that the angle variation of the slow axis is ± 7.5 degrees or less.

Further, the haze value of the substrate is preferably 1% or less. When the haze is large, the display quality often deteriorates. Therefore, the value of haze is more preferably 0.1.
5% or less.

The method for producing the above-mentioned base material is not particularly limited, and examples thereof include a method for obtaining the above-mentioned polycarbonate resin by a usual extrusion molding method, a solution casting method and the like. The solution casting method is more advantageous in terms of reduction of retardation, but if sufficient measures can be taken to reduce molecular orientation, the extrusion molding method is preferable in terms of productivity.

In order to ensure long-term reliability of the liquid crystal display element, the substrate for a liquid crystal display panel of the present invention has a gas barrier layer for preventing intrusion of oxygen and moisture and a hard coat on at least one surface of the substrate made of the polycarbonate resin. Such as a solvent-resistant layer having a cross-linking structure or a laminate of transparent conductive layers can be arranged.

For example, when the gas barrier layer is formed by a wet coating method, examples of the barrier material include polyvinyl alcohol, polyvinyl alcohol-based polymers such as polyvinyl alcohol-ethylene copolymer, polyacrylonitrile, and polyacrylonitrile-styrene copolymer. A known coating material such as polyacrylonitrile-based polymer or polyvinylidene chloride can be used.

The coating method is not particularly limited, but a known method such as a reverse roll coating method, a gravure roll coating method, or a die coating method can be used. Further, when the adhesiveness and wettability with the substrate or the substrate surface are poor, an easy adhesion treatment such as a primer treatment can be appropriately performed.

In the case where the gas barrier layer is formed by a dry process such as sputtering or vacuum deposition, at least one metal selected from known barrier materials such as Si, Al, Ti, Mg and Zr, or two or more metals. The oxide, nitride or oxynitride thin film of the above metal mixture can be formed by a known method.

The thickness of these gas barrier layers may be set to a thickness at which the desired performance can be exhibited. Note that two or more types of layers such as dry / wet, dry / dry, and wet / wet may be appropriately combined and laminated.

The solvent-resistant layer for imparting solvent resistance is made of a known material such as a resin structure having a cross-linked structure of a silicone resin, a cross-linked structure of an acrylic resin, a cross-linked structure of an epoxy resin, or the like. It can be formed by using a coating method and a curing method. The purpose of the solvent resistance is to impart durability to solvents and chemicals at the time of assembling the liquid crystal panel, and a material capable of sufficiently securing alkali resistance, acid resistance, and stability to organic solvents such as N-methylpyrrolidone. It is preferable to select curing conditions.

When the gas barrier layer and the solvent-resistant layer are laminated on each other, a primer layer can be appropriately provided for the purpose of improving the adhesion between the respective layers. As the primer layer, a silicon-based material containing a silane coupling agent or the like, an acrylic-based material, an acrylic-urethane-based material, or a material containing an alkoxytitanium or the like is applied by a method such as gravure or microgravure coating, and is appropriately provided by drying. be able to.

For use as a substrate for a liquid crystal display panel, a layer made of a transparent conductive film may be formed on at least one surface of a substrate which has been processed, for example, the above-mentioned gas barrier layer or solvent-resistant layer. As the transparent conductive film, a known electrode material used for a glass substrate in terms of transparency, conductivity, reliability, and the like can be used. Examples of such an electrode material include indium-tin oxide, fluorine-doped tin oxide, cadmium-tin oxide, vanadium oxide, and aluminum-zinc oxide-based materials. Preferably, it is indium-tin oxide. Additives can be added as needed. For example, a case where zinc oxide is added to indium-tin oxide and a case where zinc oxide is added to indium oxide can be exemplified.

The transparent conductive film of indium-tin oxide can be formed by a known method such as a sputtering method, a vacuum deposition method and an ion plating method. In order to improve the adhesion between the indium-tin oxide layer and the underlying material, it is also possible to appropriately select the primer layer and to undercoat.

The thickness of the liquid crystal display panel substrate of the present invention is 5
It is preferably from 0 to 700 μm. If the thickness is less than 50 μm, there is a problem that handling becomes difficult in a substrate manufacturing process. When the thickness is more than 700 μm, not only the characteristic of the resin base material that is lightweight is lost, but also the display quality is deteriorated due to an increase in parallax, which is not preferable. The thickness of the substrate is more preferably 70 to 500 μm.

[0046]

The substrate for a liquid crystal display panel of the present invention has high heat resistance and sufficient optical and mechanical properties. Therefore, it is possible to meet the demand for higher definition of the liquid crystal display while utilizing the features of the resin substrate, and it is useful as a substitute for a glass substrate.

The substrate for a liquid crystal display panel of the present invention can be used as an electrode material for a display, such as a photoelectrode for a photosensitive member, a surface heating element, an electrode for an organic EL, as well as a liquid crystal display device. Further, it can be used for all display substrates requiring a transparent conductive substrate such as an EL display, an electrochromic display, and an electrophoretic display.

[0048]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples. The intrinsic viscosity [η] of the polycarbonate resin was determined by extrapolation using a Ubbelohde viscometer at 20 ° C. in a methylene chloride solvent. Various evaluations of the following examples and comparative examples were performed in the following manner.

<Organic Solvent Resistance> A few drops of N-methylpyrrolidone (NMP), which is a typical solvent for the liquid crystal alignment film precursor, was dropped on the sample surface on which the solvent resistant layer was formed.
After standing for minutes, changes in the surface, such as cloudiness, swelling, and dissolution, were visually observed. When no change was observed, it was evaluated as having organic solvent resistance.

<Alkali Resistance> The sample was immersed in a 3.5 wt% aqueous sodium hydroxide solution used at the time of dissolving the resist after patterning at 30 ° C. for 10 minutes, and then thoroughly washed with running water and dried. The appearance of the surface was visually observed. At that time, when no change was observed, it was determined that the composition had an alkali aqueous solution resistance.

<Acid resistance> An etching solution (a mixture of 35 wt% ferric chloride aqueous solution, 35 wt% hydrochloric acid, and water mixed at a ratio of 1: 1: 10) used for patterning the transparent conductive layer is added at 30 ° C. at 10 ° C. After immersion for about 1 minute, the resultant was sufficiently washed with running water and then dried, and the appearance of the surface was visually observed. At that time, when no change was observed, it was determined to have acid resistance. When all of the above-mentioned organic solvent resistance, alkali resistance, and acid resistance were obtained, the composition was considered to have solvent resistance.

<Gas Barrier Property> The gas barrier property was measured by measuring oxygen permeability and water vapor permeability. Oxygen permeability is MOCO
Using Oxytran 2 / 20ML manufactured by N Corporation, 30 ° C, 50
% RH and a high humidity environment of 30 ° C. and 90% RH. The water vapor transmission rate was measured under the humidification condition of 40 ° C. and 90% RH using Percontran W1A manufactured by MOCON with the surface opposite to the surface on which the transparent conductive layer was provided facing the humidification side.

<Retardation> The retardation was measured at 590 nm using an M-150 type ellipsometer manufactured by JASCO Corporation.

Example 1 284 parts by weight of 3,3 ', 5,5'-tetramethylbisphenol A and 225 parts by weight of DPC were used as catalysts in the presence of 0.2 part by weight of sodium salt of bisphenol A under a nitrogen stream in the range of 200 to 280 parts. Polymerization was performed by a dephenol reaction at ℃ to obtain a homopolymer of 3,3 ′, 5,5′-tetramethylbisphenol A. [η] = 0.35.

This resin was dissolved in methylene chloride to prepare a 22% by weight solution. The resulting solution was cast on a polyester film by a die coating method, and then dried. Table 1 summarizes the physical properties of the obtained base material.

A solvent-resistant layer was formed on both sides of the substrate.
As a coating solution for forming the solvent-resistant layer, 50 parts by weight of light acrylate DCP-A manufactured by Kyoeisha Chemical Co., Ltd.
A mixture of 50 parts by weight of -methoxy-2-propanol, 3.5 parts by weight of Irgacure 184 manufactured by Ciba Geigy, and 0.02 parts by weight of SH28PA manufactured by Dow Corning Toray Co., Ltd. was used.

This coating solution was coated using a bar coater, and heated at 60 ° C. for 1 minute to volatilize and remove the residual solvent in the coating film. Then, using a 160 W / cm high pressure mercury lamp,
The coating film was cured by irradiating ultraviolet rays under the conditions of an integrated light quantity of 700 mJ / cm ² to form a solvent-resistant layer having a thickness of 4.5 μm.

Further, an SiOx layer was formed as a gas barrier layer on one side of the laminated substrate having the solvent resistant layer formed on both sides by sputtering. After the substrate was set in the continuous sputtering apparatus and evacuated to 1.3 mPa, Ar / O ₂ = 70/30
Was introduced to bring the atmospheric pressure to 0.22 Pa. Using silicon as a sputtering target, the input power density is 1 W / cm ² , the substrate temperature is DC at room temperature.
Sputtering was performed to form a SiOx layer having a thickness of 30 nm.

Further, an indium-tin oxide thin film layer, which is a transparent conductive thin film, was formed on the surface opposite to the gas barrier layer by sputtering. An indium-tin oxide target (molar ratio: indium / tin = 90/10, packing density: 95%) as a sputtering target for that purpose
Was used. Set the film in the continuous sputtering device,
After evacuating to a pressure of 1.3 mPa, Ar / O ₂ = 98.
Atmospheric pressure of 0.27P by introducing a mixed gas of 5 / 1.5
a. Then, the substrate temperature was set to 60 ° C., and DC sputtering was performed at a power density of 1 W / cm ² . The resulting transparent conductive film had a thickness of 30 nm and a surface resistance of 250 Ω / sq.

Table 2 summarizes the results of the gas barrier property, water vapor barrier property, and solvent resistance test of this liquid crystal display panel substrate.

When heat treatment was performed at 140 ° C. for 2 hours, no curl change (change in warpage) and no change in appearance occurred.

Next, two 7 cm square samples were cut out from the liquid crystal display panel substrate. And for each of the two samples,
Hitachi Chemical S, a low-temperature curable polyimide as an aligning agent
TX-24 was diluted and dissolved in N-methylpyrrolidone and spin-coated. Subsequently, this was cured at 140 ° C. for 2 hours, and rubbed 15 times with a rubbing machine with a polyester rubbing roll. Then, micropearls made by Sekisui Fine Chemical were sprayed as spacers. Thereafter, Araldite manufactured by Ciba-Geigy was screen-printed as a sealant.

The two samples processed as described above were
The laminate was cured by applying pressure at 2 ° C. for 2 hours to form a liquid crystal cell. The cell gap of this liquid crystal cell was 6 μm as measured by the capacitance capacitance method.

As a liquid crystal material, Kiracol 6228 manufactured by Asahi Denka was injected from the opening of the liquid crystal cell using a liquid crystal injection device. After the injection, the liquid crystal material was heated to a liquid crystal phase transition temperature, and then gradually cooled to room temperature to complete the alignment. The orientation is 180-degree STN by bonding the substrates in 180-degree orientation.
It was confirmed that they were oriented.

The cell obtained as a result had a uniform color tone and an ON response of 60 msec at an applied voltage of 1.8 V.
c and below, the OFF response was confirmed to be a response of the STN liquid crystal cell of 25 msec or less.

Example 2 Fluorene-9,9-di (4-
Phenol) 105 parts by weight, bisphenol A160
Parts by weight of 225 parts by weight of DPC and 0.2 parts by weight of sodium salt of bisphenol A as a catalyst in a nitrogen stream,
Polymerized by a dephenol reaction at 0 to 280 ° C., and fluorene-9,9-di (4-phenol) unit is 30 mol%.
The contained copolymerized polycarbonate was obtained. [η] = 0.3
It was 2.

This resin was dissolved in methylene chloride to prepare a 22% by weight solution. The resulting solution was cast on a polyester film by a die coating method, and then dried. Table 1 summarizes the physical properties of the obtained base material.

The method for manufacturing a liquid crystal display panel substrate is described in Example 1.
The same was done. Table 2 shows the results of the gas barrier, water vapor barrier, and solvent resistance tests of this panel.

The cell obtained as a result had a uniform color tone and an ON response of 60 msec at an applied voltage of 1.8 V.
c and below, the OFF response was confirmed to be a response of the STN liquid crystal cell of 25 msec or less.

Example 3 Fluorene-9,9-di (3-
Methyl-4-phenol) 114 parts by weight, 160 parts by weight of bisphenol A and 225 parts by weight of DPC are polymerized by a dephenolation reaction at 200 to 280 ° C. under a nitrogen gas stream using 0.2 parts by weight of sodium salt of bisphenol A as a catalyst. A copolymerized polycarbonate containing 30 mol% of -9,9-di (3-methyl-4-phenol) unit was obtained. [η] = 0.35.

This resin was dissolved in methylene chloride to prepare a 22% by weight solution. The resulting solution was cast on a polyester film by a die coating method, and then dried. Table 1 summarizes the physical properties of the obtained base material.

A method for manufacturing a liquid crystal display panel substrate is described in Example 1.
The same was done. Table 2 shows the results of the gas barrier, water vapor barrier, and solvent resistance tests of this panel.

The resulting cell has a uniform color tone and an ON response of 60 msec at an applied voltage of 1.8 V.
c and below, the OFF response was confirmed to be a response of the STN liquid crystal cell of 25 msec or less.

Example 4 Polycarbonate resin APEC-HT manufactured by Bayer AG (3,3,5-trimethyl-1,1-di (4-phenol) cyclohexylidene / bisphenol A = 58/42: molar ratio, η] = 0.45) was dissolved in methylene chloride to prepare a 27% by weight solution. The resulting solution was cast on a polyester film by a die coating method, and then dried. Table 1 summarizes the physical properties of the base material.

The method for producing a liquid crystal display panel substrate is described in Example 1.
The same was done. Table 2 shows the results of the gas barrier, water vapor barrier, and solvent resistance tests of this panel.

The cell obtained as a result had a uniform color tone and an ON response of 60 msec at an applied voltage of 1.8 V.
c and below, the OFF response was confirmed to be a response of the STN liquid crystal cell of 25 msec or less.

[0077]

[Table 1]

[0078]

[Table 2]

[Comparative Example] A polycarbonate resin having an average molecular weight of 24,000 ([η] = 0.43) consisting solely of bisphenol A was dissolved in methylene chloride to prepare a solution having a concentration of 22% by weight. The prepared solution was cast on a polished stainless steel belt by a casting method using a die under an environment of a temperature of 20 ° C. and a humidity of 60% RH, and then dried. The physical properties of this substrate are shown in Table 1 above.

Claims (11)

[Claims] [Claim 1] The following formula (1) [In the above formula (1), R _{1 to} R ₈ are each independently selected from a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms, and X is a hydrocarbon group having 1 to 15 carbon atoms.
However, when R _{1 to} R ₈ are hydrogen atoms, X is not an isopropylidene group. ] A liquid crystal display panel substrate based on an aromatic polycarbonate resin comprising a repeating unit represented by the following formula: 2. The repeating unit represented by the above formula (1), and the following formula (2): For a liquid crystal display panel comprising a copolymerized polycarbonate resin comprising a repeating unit represented by the formula (1), wherein the repeating unit represented by the formula (1) is 30 to 99 mol% of the whole. substrate. 3. The following formula (3): [In the above formula (3), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms. However, R _{1 to} R ₈ are not simultaneously hydrogen atoms. ]
A substrate for a liquid crystal display panel using a polycarbonate resin comprising a repeating unit represented by the following formula: 4. The following formula (4): [In the above formula (4), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms. And a repeating unit represented by the above formula (2), wherein the repeating unit represented by the above formula (4) accounts for 30 to 99 mol% of the whole. Substrate for liquid crystal display panel based on polymerized polycarbonate resin. 5. The following formula (5): [In the above formula (5), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 6 carbon atoms. And a repeating unit represented by the formula (2), wherein the repeating unit represented by the formula (5) is 30 to 99 mol% of the whole. Substrate for liquid crystal display panel based on polymerized polycarbonate resin. 6. A base material having a retardation value of 2
The liquid crystal display panel substrate according to any one of claims 1 to 5, wherein the thickness is 0 nm or less, the variation of the slow axis is ± 10 degrees or less, and the haze value is 1% or less. 7. The substrate has a thickness of 50 to 700 μm,
The substrate for a liquid crystal display panel according to any one of claims 1 to 6, wherein the thickness unevenness of the substrate is ± 5% or less. 8. The substrate for a liquid crystal display panel according to claim 1, wherein the glass transition temperature of the base material is 160 ° C. or higher. 9. The liquid crystal display panel substrate according to claim 1, wherein a transparent conductive layer is disposed on at least one surface of the substrate. 10. The substrate for a liquid crystal display panel according to claim 1, wherein a gas barrier layer, a solvent-resistant layer, and a transparent conductive layer are disposed on at least one surface of the substrate. 11. The following formula (1): [In the above formula (1), R _{1 to} R ₈ are each independently selected from a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms, and X is a hydrocarbon group having 1 to 15 carbon atoms.
However, when R _{1 to} R ₈ are hydrogen atoms, X is not an isopropylidene group. A substrate suitable for a liquid crystal display panel substrate, comprising an aromatic polycarbonate resin comprising a repeating unit represented by the formula: