JPS60153025A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To prevent the color of the cell of a liq. crystal display element and the visual angle from being made ununiform and to attain high display quality by sticking a gapping agent for keeping the gap between substrates uniform to an orienting films formed on one of the plastic film substrates. CONSTITUTION:Electrically conductive transparent films 2, 2 of In2O3 or the like are formed on plastic film substrates 1, 1 such as polyethylene terephthalate films. One of the substrates 1, 1 is dipped in a treating liq. prepd. by dispersing a gapping agent G such as polystyrene beads or polymer fibers in a soln. of polyamide, silicone resin or the like as an orienting agent. The gapping agent G has such hardness that the film 2 is not damaged. The dipped substrate 1 is dried with hot air to remove the solvent, and it is heat treated. The resulting film is rubbed to fix a gapping agent G on an orienting film 3. The substrate 1 is connected to the other substrate 1 having the film 2 and an orienting film 3 with a sealing agent 5 in-between, and a liq. crystal 4 is injected into the gap between the substrates. A high quality uniform display can be carried out independently of the bending of the cell or pressure or vibration applied to the cell.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a liquid crystal display element using a plastic film as a substrate.

[Prior art]

In a conventional liquid crystal display device using a plastic film as a substrate, as shown in FIG. 1, the gap material G is formed between two substrates 1.
It is sealed together with liquid crystal 4 in the cell formed in 1.

Such conventional liquid crystal display element material and gap material G are
It is a mobile item, and if pressure is applied to the liquid crystal cell, vibration is applied, or it is bent, it will move within the liquid crystal cell, resulting in variations in the response speed of the product (more than 30%). This has led to deterioration in display quality, such as uneven cell color and non-uniform viewing angles.

〔the purpose〕

The present invention aims to overcome the above-mentioned drawbacks found in conventional products.

〔composition〕

According to the present invention, a liquid crystal display element having a plastic film as a substrate is characterized in that a gap material interposed between the substrates along with the liquid crystal is fixed to an alignment treatment film provided on the substrate surface. is provided.

An explanatory cross-sectional view of the liquid crystal display element of the present invention is shown in FIG. In this figure, each symbol has the same meaning as in FIG. 1. That is, 1 is a substrate made of a plastic film, 2 and 3 are transparent electrodes and alignment films formed on the surface thereof. In the case of the present invention, the gap material G is fixed to a self-aligning treatment film formed on one of the substrates, and is non-movable. In FIG. 2, the gap material G is fixed to the alignment film of the lower substrate, but it may be fixed to the alignment film of the upper substrate.

To manufacture the liquid crystal display element of the present invention, first, an ITO film as a transparent electrode is formed on a plastic film such as polyester, polycarbonate, polysulfone, polyethersulfone, modified polyester, etc. by a conventionally known method. , perform patterning processing. Next, an alignment treatment solution is applied thereon and dried to form an alignment treatment film, but in the case of the present invention, there are A caulking gap material is dispersed, and an alignment treatment material solution in which this gap material is dispersed is applied to one substrate surface and dried. In this case, a conventionally known spin coater, roll coater, or the like can be used as a coating means, and after coating and drying, the alignment film is heated to 80 to 150° C. to be thermally cured.

The alignment treatment agent used in the present invention may be of a solvent-soluble type, such as polyvinyl alcohol, polyfluoroethylene, polyamide, polyimide, urea resin, melamine resin, phenol resin, polyvinyl chloride, polyvinyl acetate. , polymethyl methacrylate, polystyrene,
Polyvinyl butyral, polyparaxylene, polybenzimidazole, silicone resin, nitrocellulose, acetylcellulose, cellulose acetate butyrate, cellulose acetate-1 propionate, methylcellulose, polyethylene terephthalate, polyethylene, polypropylene, viscose rayon, polydimethylcyclo xane, polyurethane.

Examples include epoxy resin, polyethylene-vinyl acetate copolymer, polymethacrylic acid-vinylpyrrolidone copolymer, nylon/epoxy resin/organometallic alcoholade composition, nylon/epoxy resin composition, nylon/organometallic alcoholade composition, etc. .

In addition, the gap material used in the present invention includes polymeric substances such as polystyrene, divinylbenzene copolymer,
A polymer fiber or the like is used, and its shape is not particularly limited, but spherical or rod-like shapes are preferred, and in the case of spherical shapes,
Particle size of approximately 6 to 15 μm, in case of rod shape, diameter of approximately 6 to 15 μm
It is preferable to use a material having a length of about 10 to 200 μm. The hardness of the gap material is set to a level that does not damage the electrode (ITO), for example, 123 (J) on the Rockwell hardness.
IS K7202) is also sufficient. When the gap material is dispersed in the alignment agent solution, the amount of the gap material used is 10-5 to 1 part by weight, preferably 10-' to 10-2 parts by weight, per 1 part by weight of the alignment agent. It is a percentage.

〔effect〕

As described above, in the liquid crystal display element of the present invention, the gap material is bonded to the alignment film of the substrate in the liquid crystal cell,
Since it is immobile and is uniformly distributed over the alignment film, there is no display quality even if the cell is bent or pressure and vibration are applied to the cell.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

Example A plastic panel substrate comprising a polyethylene terephthalate film with a thickness of 75 μm and a transparent conductive film containing indium oxide as the main component was immersed for 1 minute in the following alignment treatment agent solution in which a gap material was dispersed, and then heated with hot air. The solvent was removed by drying, followed by heat treatment at 150°C for 30 minutes.

[Orientation treatment material solution composition]

(1) Nylon (melting point peak 103°C) 10 parts by weight (2
) Epoxy resin (Shell Epiko 815) 3 parts by weight (3)
Tetraoctyl titanium - 1 to 4 parts by weight (4) Gap material 0.01 parts by weight (polystyrene beads, particle size 10 μm) (5) Solvent (lower alcohol type) 82.99 parts by weight Next, as described above The obtained panel was rubbed in one direction with a cotton cloth under pressure of 1 kg/cm♂ to obtain a panel substrate A.

On the other hand, a panel substrate B was obtained in the same manner as above except that a solution containing no gap material was used as the alignment treatment agent solution.

The panel substrates A and B were stacked so that the rubbing directions were perpendicular to each other, and biphenyl liquid crystal was sealed between the substrates to obtain a liquid crystal display element. When using this liquid crystal display element,
The display quality was not impaired by bending, pressure, or vibration, and the variation in response speed was less than 10%, and there was no cell color unevenness, and good viewing angle uniformity was exhibited.

[Brief explanation of drawings]

FIG. 1 is an explanatory cross-sectional view of a conventional liquid crystal display element, and FIG. 2 is an explanatory cross-sectional view of a liquid crystal display element of the present invention. ■...Substrate, 2...Transparent electrode, 3...Alignment treatment film, 4...Liquid crystal, 5...Sealing material, G...Gap material. Patent applicant Ricoh Co., Ltd. - Representative patent attorney Toshiaki Ikeura Figure 1 Figure 2

Claims (1)

[Claims] (1) A liquid crystal display element having a plastic film as a substrate, characterized in that a gap agent interposed between the substrates together with the liquid crystal is fixed to an alignment treatment film provided on the substrate surface.