JPS6190132A - Liquid crystal panel - Google Patents

Abstract

PURPOSE:To improve an excellent aging resistance of the titled panel by forming an orientation controlled film contg. a reaction product of an alkoxy org. indium, a nylon resin and an epoxide resin as a main component on a substrate. CONSTITUTION:The orientation controlled film 3 is prepared by vapor-depositing or low temp. sputtering an electrode 2 composed of a transparent electrode film contg. stannic oxide and indium oxide as the main component on the sub strate 1 comprising the inorg. glass and the plastic film and then coating the plate 1 with a solution dissolving the alkoxy org. indium, the nylon resin and the epoxide resin in a solvent of alcohol etc and heating and drying the obtd. film. The titled panel is formed by enclosing the liquid crystal material together with a chipping material 6 which is used to maintain a space between the substrates 1 into the space between the substrates arranging the electrode 2 and the orientation controlled film 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal panel used in various displays, etc., in which a liquid crystal substance is sealed between a pair of substrates.
In particular, the present invention relates to an alignment control film formed on a substrate surface to adjust the alignment of liquid crystal molecules in such a liquid crystal panel.

[Prior Art] In general, a liquid crystal panel has a liquid crystal material sealed between a pair of substrates, at least one of which is transparent, provided with electrodes mainly made of tin oxide or indium oxide, so that a voltage can be applied between the electrodes. It has become. This LCD panel is
It is widely used for various types of display, and the orientation of liquid crystal molecules is adjusted in order to improve the clarity of displayed images. As a means for adjusting the alignment of liquid crystal molecules, it is known to form an ultra-thin film having an effect of controlling the alignment of liquid crystal molecules, that is, an alignment control film, on the substrate surface.

Conventionally, as the above-mentioned orientation ul 1111fl'J, a film formed by forming a film of a reaction product of nylon, epoxy resin, and organic titanate as an orientation control film is known (Japanese Unexamined Patent Publication No. 14220/1982). This alignment control film is produced by applying the above-mentioned mixed solution onto a substrate and then heating it at a relatively low temperature.
Since it can be formed at a temperature of 130 to 150[deg.] C., it has the advantage of being applicable even when a plastic substrate is used, which is excellent in mass production, or when a switching element that is sensitive to heat is installed.

However, according to experiments conducted by the present inventors, when a liquid crystal panel is formed with an alignment control film as described above, there is a problem in that it is difficult to obtain sufficient aging resistance. If the aging resistance is insufficient, the alignment of liquid crystal molecules will be disturbed over time, and soot will appear in the image, resulting in a decrease in sharpness.

[Problems to be Solved by the Invention] The present invention can be formed by heating at a relatively low temperature, which is sufficient even when the substrate is made of plastic or when a switching element that is sensitive to heat is installed. The problem to be solved is to obtain a liquid crystal panel that exhibits excellent aging resistance.

[Means for Solving the Problems] The measures taken to solve the above problems in the present invention are to apply nitrogen containing a reaction product of alkoxy organic indium, nylon, and epoxy resin as a main component to the substrate surface. The object is to provide a liquid crystal panel formed as an alignment control film.

[Function] In the present invention, nylon exhibits an excellent alignment effect, and the alkoxy organic indium and epoxy resin act as a reinforcing agent to form a stable film without impairing the alignment effect of nylon. Furthermore, the alkoxyorganic indium also has a function that supplements the orienting function of nylon.

Although the reaction patterns of these champions are not necessarily clear, the present inventors speculate as follows. That is, while it is known that nylon and epoxy resin undergo condensation polymerization,
Since alkoxyorganic indium and nylon are difficult to react directly, nylon and epoxy resin first undergo condensation polymerization, and alkoxyorganic indium is bonded to the epoxy resin bonded to the nylon in a form similar to a frontal bond, forming the entire structure. It is thought that it is being stabilized. Since these reactions can be obtained at a relatively low temperature, a stable orientation control film with excellent orientation can be obtained by heating at a relatively low temperature. [Example] Fig. 1 , 1 is a substrate, 2 is an electrode made of a transparent conductive film provided on the substrate l, 3 is an alignment control film, 4 is a sealing material layer, 5 is an upper and lower conductive layer, 6 is a gap agent, and 7 is a liquid crystal material. be.

At least one side of the substrate 1 is transparent, and in addition to inorganic glass,
For example, plastic films such as aromatic heat-resistant polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyethersulfone, polysulfone, polycarbonate, cellulose acetate, diene rubber, acrylic resin, and urethane resin can be used.

When the substrate 1 is made of a plastic film, the mass productivity of the liquid crystal panel is improved, and the alignment control film 3, which will be described later, is particularly useful when the substrate 1 is made of a plastic film.

The electrode 2 provided on the substrate 1 is a transparent conductive material mainly made of, for example, tin oxide or indium oxide, and is attached to the substrate 1 by vapor deposition, low-temperature sputtering, CvD, or the like. Further, the substrate 1 is provided with a film as an alignment control film 3, which is mainly composed of a reaction product of alkoxyorganic indium, nylon, and epoxy resin, which will be described later. A liquid crystal substance 7 is sealed between the substrates 1 provided with the electrodes 2 and the alignment control film 3, together with a gap agent 6 for maintaining the distance between the substrates 1.

Next, the alignment control film 3 will be explained in more detail.

First, alkoxyorganoindium [In(OR) 3] (
R is an alkyl group such as ethyl, propyl, butyl, etc.) It is preferable that R is an isopro group for reasons such as high manufacturing purity, excellent orientation control ability, and excellent action as a reinforcing agent.

As the nylon, a nylon copolymer is preferable from the viewpoint of ease of handling, and specific examples include 6-nylon, 6.6-nylon, and 12-nylon, and among them, 12-nylon is preferred from the viewpoint of ease of forming J1λ. preferable.

Further, the nylon is preferably an alcohol-soluble nylon copolymer from the viewpoint of workability in film formation. In addition, especially when the substrate 1 is made of plastic or when a switching element that is sensitive to heat is installed, the melting point should be set at about 80 to 130 °C so that a film with excellent orientation control ability can be obtained by heating at as low a temperature as possible. Preferably, nylon is used.

Epoxy resins include glycidyl ether type, glycidyl ester type, bisphenol type, glycidyl amine type, cycloaliphatic type, linear aliphatic type, etc. Bisphenol type A is preferred. In particular, a liquid material having a sufficient ability to control the orientation of the film and in which 0HCH3 CH-CH2)- is O to 3 is preferred.

Alkoxy organic indium (A), nylon (B),
The component ratio of the epoxy resin (C) in the orientation control film 3 is A
/B/C= 5~30/10-1'00/1~10 (
In terms of weight ratio, A is preferably (in terms of In20.1), and optimally A/B/C is around 21/4/2.

Orientation I of a material whose main component is a reaction product of alkoxy organic indium, nylon, and epoxy resin as described above.
Forming I#DQ3 on the substrate l can be easily performed as follows.

That is, the alignment control film 3 can be obtained by dissolving alkoxy organic indium, nylon, and epoxy resin in a solvent, applying this solution to the surface of the substrate 1, and then heating and drying it.

Examples of the solvent include alcohols such as ethanol, methanol, butanol, isopropyl alcohol, propatool, ketones such as acetone methyl ethyl ketone and dimethyl ketone, cyclic ethers such as tetrahydrofuran and dioxane, and mixtures thereof. , are selected in consideration of solubility with each component, non-reactivity with each component, evaporability during film formation, etc. The ratio of the three components as solid content to this solvent is 0.1 to 5.
The amount is preferably 3% by weight or less, particularly 3% by weight or less in order to obtain excellent alignment performance and film uniformity.

The solution can be easily applied to the substrate 1 by a dipping method or a spraying method. Drying after coating 1'5 on the substrate 1 is preferably carried out at 60 to 1'50°C for about 30 to 300 minutes. From the point of view of preventing partial orientation defects, especially 10
0 to 200 minutes is appropriate. After this drying, 20 to 200 g/crn2. Optimally 100 g/
It is preferable to perform the rubbing under a static pressure of about cm 2 because an alignment control film 3 with a better alignment state can be obtained.

The orientation control film 3 in the present invention can be easily formed as described above, and does not require a vacuum process, a patterning (etching, peeling) process, or a printing process, so that continuous mass production is easy.

Example 1 A solution having the following composition was applied to a substrate comprising a polyethylene terephthalate film with a thickness of 100 g and a transparent conductive film containing indium fertilized as a main component as an electrode, and heated at 120°C.
and dried for 120 minutes. Furthermore, the electrodes were attached using a low-temperature sputtering device to keep the film surface temperature below 120°C.

Solution composition Q Added solvent Ethanol 13g Methyl ethyl ketone 3g o Alkoxy organic indium In-(003H7) 3In20 equivalent: 2.1go Nylon 12-nylon copolymer (trade name: Diamid Daicel Chemical Industries, Ltd. 0.4g) Molecular weight: 1000~ 1500 Melting point peak 105℃ 0 Epoxy resin Bisphenol A type epoxy resin (Product name: Epicote 828 Shell Chemical Co., Ltd. % Formula % (25℃) Epoxy equivalent 184-194 However, In('QC3H7) 3 is hydrated when left in air. For decomposition, 2.5% by weight (In
203 conversion) was used.

Solvent system n-butanol 16% by weight isopropyl alcohol 201/acetylacetone
21/Propionic acid 2
41/ethyl alcohol 32 tr turpentine 6 // and the amounts of ethanol and methyl ethyl ketone were adjusted depending on the amount of this solvent system and were kept constant.

After applying the above solution to the substrate and drying it, 100 g
Rub in one direction under pressure of /cm2, stack two of these substrates so that the upper and lower rubbing directions are perpendicular, and place Loche RO-TN-619 liquid crystal (pyrimidine-based Δ
ε〉0 nematic liquid crystal) was filled to form a liquid crystal panel.

Table 1 shows the results of the durability test of this liquid crystal panel.

Example 2 Epikote 828, the epoxy resin used in Example 1
(trade name, manufactured by Shell Chemical Co., Ltd.) with a viscosity of 8 to 1 lc.
A liquid crystal panel was produced in the same manner as in Example 1, except that Epikote 815 (trade name, manufactured by Shell Chemical Co., Ltd.) having an epoxy equivalent of 183 to 183 was used.

Table 1 shows the results of the durability test of this liquid crystal panel.

Example 3 A liquid crystal panel was produced in the same manner as in Example 1 except that the polyethylene terephthalate film used as the substrate in Example 1 was replaced with polyether sulfone. Table 1 shows the results of the durability test of this liquid crystal panel.

Example 4 A liquid crystal panel was produced in the same manner as in Example 1, except that indium octylate (OCB HI3)'3 was used in place of the impropoxy indium used in Example 1. Table 1 shows the durability test results of this liquid crystal panel.

Comparative Example 1 A liquid crystal panel was produced in the same manner as in Example 1 except that the alkoxyorganic indium used in Example 1 was replaced with tetraoctyl titanate. Table 1 shows the results of the durability test of this liquid crystal panel.

Comparative Example 2 A liquid crystal panel was produced in the same manner as in Example 1 except that the alkoxy organic indium used in Example 1 was replaced with octyl ugly organic aluminum. Table 1 shows the results of the durability test of this liquid crystal panel.

Table 1 0 Uniform orientation Δ: Partially defective orientation (domain, rubbing streaks, etc.) Hair growth Xz No horizontal orientation Successful orientation area M5Q% or less
A liquid crystal panel was placed between two polarizing plates arranged so that the polarization directions were perpendicular to each other, and the alignment state of the liquid crystal panel due to transmitted light was visually observed from the normal direction to the panel surface.

[Effect of the Invention 1 According to the present invention, a liquid crystal panel with extremely excellent durability can be obtained. Moreover, the alignment control film of the liquid crystal panel exhibits the above-mentioned durability and excellent alignment control effect when heated at low temperatures, so it can be used even when a plastic substrate or a switching element that is sensitive to heat is installed, increasing the productivity of the liquid crystal panel. It is something that can improve.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an example of a liquid crystal panel according to the present invention. DESCRIPTION OF SYMBOLS 1: Substrate, 2: Electrode, 3: Orientation control film, 4: Seal material layer, 5: Vertical conductive layer, 6: Gap agent, 7: Liquid crystal substance.

Claims (1)

[Scope of Claims] 1) A liquid crystal panel characterized in that a film mainly composed of a reaction product of alkoxyorganic indium, nylon, and epoxy resin is formed on a substrate surface as an alignment control film. 2) Claim 1, wherein the substrate is a film of aromatic heat-resistant polyester, polyether sanphone, polysulfone, polycarbonate, cellulose acetate, diene rubber, acrylic resin, or urethane resin. LCD panel described in section. 3) Alkoxy organic indium [In-(OR)_3]
2. The liquid crystal panel according to claim 1, wherein R is an isopro group. 4) The liquid crystal panel according to claim 1, wherein the nylon is a nylon copolymer. 5) The liquid crystal panel according to claim 4, wherein the nylon copolymer contains 12-nylon. 6) The liquid crystal panel according to claim 4, wherein the nylon copolymer is alcohol-soluble. 7) The liquid crystal panel according to claim 1, wherein the nylon has a melting point peak of 80 to 130°C. 8) The liquid crystal panel according to claim 1, wherein the epoxy resin is a bisphenol type. 9) The liquid crystal panel according to claim 8, characterized in that it is a bisphenol A type epoxy resin. 10) The liquid crystal panel according to claim 9, wherein ▲ where ▲ includes a mathematical formula, chemical formula, table, etc. ▼ in the bisphenol A type epoxy resin is 0 to 3.