JPS6146902A - Polarizing substrate - Google Patents

Abstract

PURPOSE:To obtain a polarizing substrate which decrease gas permeability of steam, etc. and can extend the life of a polarizer and a liquid crystal display device having the polarizer by providing a uniaxially stretched optically transparent plastic film to one surface of the polarizer and a thin glass plate to the other surface. CONSTITUTION:The polarizer which is formed by adsorbing and orienting an I2 or dichromatic dye to a PVA film and is adhered with a glass plate having 50mu-1mm. thickness on one surface by a polyester adhesive agent is adhered by means of the polyester adhesive agent to one surface of the uniaxially oriented polyester film such as the polyester film uniaxially stretched 50-800% in such a manner that the plane of polarizer is positioned on the uniaxially stretched film side and that the absorption axis of the polarizer is made parallel or orthogonal with the stretching axis of the film to obtain the polarizing substrate. An electrode pattern is formed on the uniaxially stretched film side and a liquid crystal is sealed between said substrate and the substrate having a counter electrode. The thin and lightweight liquid crystal display cell having a long life with less deformation is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polarizing substrate mainly used in liquid crystal display devices.

<Conventional technology> Recent technology 1. There is a growing demand for lighter weight and thinner liquid crystal display devices, and current methods for achieving this are changing from the conventional configuration in which polarizing plates are placed on both sides of a liquid crystal display cell in which liquid crystal is sealed between glass substrates, to Various configurations have been proposed that use a liquid crystal display cell in which liquid crystal is sealed between two polarizing substrates each provided with a plastic film.

<Problems to be Solved by the Invention> However, a liquid crystal display cell formed by sealing a liquid crystal between two polarizing substrates each having a plastic film on both sides of a polarizer is a liquid crystal display cell formed by using a glass substrate. Compared to display cells, they are deformed by external pressure and cannot maintain a cell gap, making it difficult to obtain a clear display; they are highly permeable to gases such as water vapor, and the lifespan of polarizers and liquid crystals is shortened; There are also drawbacks such as deformation over time due to expansion and contraction of the plastic film due to heat and moisture absorption, and there is currently a need for improvement.

<Means for Solving the Problems> The present invention solves the drawbacks of the prior art and provides a new polarizing substrate. A plastic film having optical transparency such as a film is provided, and a thin glass plate is provided on the other side.The polarizing substrate has an electrode pattern formed on one side K, preferably on the plastic film side, by a conventional method. By using the cell substrate as a cell substrate, arranging the patterned surfaces with a predetermined gap so that they are in contact with each other, filling the liquid crystal, and sealing the periphery, there is little deformation, long life, and shrinkage over time. A good liquid crystal display cell without deformation can be obtained.
The polarizer used to carry out the present invention may be a nine-iodine and/or dichroic dye-based polarizer in which iodine and/or dichroic dye is adsorbed and aligned as a polarizing element, or a highly hydrophilic polarizer such as polyvinyl alcohol. Polyene polarizers with oriented polyenes are used, either by dehydrating a molecular film or by dehydrochlorinating a polyvinyl chloride film.

As the plastic film, optically transparent films such as polyester, polysulfone, polyethersulfone, polycarbonate, triacetate, epoxy resin, and phenoxy resin are used, but preferably the film is uniaxially stretched by 50 to 800%. The thin glass plate, which is a stretched film such as a uniaxially stretched polyester film made of a polyester film, is made of soda glass, borosilicate glass, organic glass, etc. and has a thickness of 50 μm or more. It is preferable to laminate the film and the stretched film so that the absorption axis of the polarizer and the stretching axis of the film are parallel or perpendicular to each other.However, as long as the angular error is within about 5 degrees, the error is acceptable due to optical properties. ◇ <Effects of the Invention> Since the polarizing substrate of the present invention is constructed and used as described above, a liquid crystal display device using the same can maintain a cell gap, resulting in good display. Furthermore, the liquid crystal has a long lifespan and does not deform over time.

<Example> Next, examples of the present invention will be shown.

Example 1 Iodine was adsorbed and oriented on a polyvinyl alcohol film with a thickness of 75 μm to obtain an iodine polarizer with a thickness of 25 μm.

A glass plate having a thickness of lff is adhered to one side of the polarizer using a polyester adhesive, and a uniaxially stretched polyester film having a thickness of 100 μm is attached to the other side with the absorption axis of the polarizer parallel to the stretching axis of the film. The polarizing substrate of the present invention was obtained by bonding with the adhesive described above. When this polarizing substrate was treated at 100°C for 4 hours, the transmittance was 42.34, the degree of polarization was 95.2%, and the shrinkage was The ratio and deformation (curl height) were 0 and 6.90 Example 2 A polarizing substrate was prepared in the same manner as in Example 1 except that the absorption axis of the polarizer and the stretching axis of the film were made perpendicular to each other. I got it.

When this polarizing substrate was treated at 100°C for 4 hours, the transmittance was 40.1qb1, the degree of polarization was 94.4cm, the shrinkage rate and...
Deformation is 0, 90

Claims (1)

[Claims] 1) A polarizing substrate in which a polarizer is provided with an optically transparent plastic film such as a uniaxially stretched polyester film on one side and a thin glass plate on the other side.