JPS58142315A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To vertically orient a liq. crystal and to obtain a clear color display by forming innumerable needlelike protrusions by high frequency sputter etching treatment. CONSTITUTION:The surface of plastic films made of tetrafluoroethylene-hexafluoropropylene copolymer resin, trifluorochloroethylene resin, perfluoroalkoxy resin or polymethyl methacrylate are subjected to high frequency sputter etching treatment at several 100- several 10kHz frequency. Innumerable needlelike protrusions 7, 7' are formed on the film surfaces 2, 2' by the treatment. Transparent electrodes 8, 8' are then formed on the prescribed parts of the films by sputtering, ionic plating or other method while preventing a practical change in the shape of the protrusions 7, 7'. The films are placed so that the treated surfaces face to each other, and a liq. crystal 3 is sealed in the gap between the films. Polarizing plates 1, 1' are put on the other surfaces of the films, and color display is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal display device capable of displaying unexploded W ore.

Liquid crystal display devices are used in watches, desk calculators, and automobile instrumentation.
It is used for various public funds such as...

Conventionally, in this type of liquid crystal display device, electrodes are provided between two polarizing plates, and the liquid crystal molecules are oriented parallel to the OIi direction of the polarizing plate (parallel alignment), and one surface of these polarizing plates is A structure in which a reflective plate such as aluminium foil is arranged on the other surface of glass for holding noodles is mainly used.

The conventional liquid crystal display described above displays characters and graphics by changing the molecular arrangement of the liquid crystal by applying a voltage between the electrodes.
Until now, it was not possible to display characters, figures, etc. in color, but if color display was desired, an Fi coloring filter had to be placed in the mold, which was a hassle.

By the way, in order to display a color image without disposing a colored filter, it is necessary to orient the liquid crystal perpendicularly to the surface direction of the polarizing plate and cause birefringence of light by the liquid crystal when voltage is applied. 〇 Transparent plastic is known as a means for straight alignment of liquid crystals.
By rubbing the surface of the ballistic film in one direction with a cloth, the surface of the ballistic film is rubbed in one direction. A method of orienting the liquid crystal on this film using an OPS method, or a method of orienting the liquid crystal on a transparent plastic film on which SiO is obliquely deposited, and a chemical treatment section have been proposed. In either method, direct alignment of the liquid crystal OA is still insufficient, and the current situation is that it is difficult to obtain a clear color display.

The inventors of the present invention have made intensive studies in view of the above-mentioned current situation, and found that when two films are formed such that a projection is formed and two films are arranged so that their treated surfaces face each other, and a liquid crystal is sealed between the films, the film ll! It was discovered that liquid crystals can be vertically aligned by the needle-like protrusions formed on the surface, resulting in clear color display, and this led to the completion of the present invention.

That is, in the liquid crystal display device according to the present invention, two transparent plastic films A each having one side subjected to high frequency sputter etching treatment and having invincible acicular protrusions formed thereon, are heated by the high wave sputter etching treatment SWt. A liquid crystal is sealed between these films, and a polarizing plate is further arranged on the other surface of the transparent plastic film.

The material of the transparent plastic film used in the present invention is not particularly limited, but 1 m1! 47 because of the ease of forming needle-like protrusions by I4 wave sputter etching process.
Preferred are ethylene fluoride-67 propylene fluoride copolymer resins, trifluorochlorinated ethylene 411 resins, perfluoroalkoxy trifluorocarbons, or polymethyl methacrylate. These transparent plastic films are used with one side subjected to high frequency sputter etching treatment.

The sputter etching process on the surface of the transparent plastic film has a frequency of several hundred 11J1z w#! i knee M
Although this can be done using high frequency Hg (), it is practically preferable to use the industrially allocated frequency of 13.56 MHg. The processing conditions at this time are set depending on the material of the plastic film, but usually TTGS atmospheric pressure o, ooos ~ 0.
5 T@rr preferably 0.005 to 0.15 Tar
The discharge power density is 0.1 to 5 watts, /; and the processing time is several seconds to several minutes. In addition, the atmospheric gas is not particularly limited, but may include inert gas such as argon, air, nitrogen,
Water vapor etc. are practical.

By this high frequency sputter etching process, countless needle-like protrusions with a length of approximately 0.1 to 10 digits are formed on the treated surface of the transparent plastic film, and these needle-like protrusions exhibit vertical alignment of liquid crystal molecules and absorb light. As a result, clear color display can be achieved without using colored filters.

Next, the present invention will be explained in detail with reference to figures and planes. In FIG. 1, 1.1' is a polarizing plate, on which transparent plastic films 2 and 2' each having one side subjected to high-frequency sputter etching treatment are arranged so that the treated surfaces face each other. A liquid crystal 3 such as a nematic liquid crystal or a smectic liquid crystal is sealed between two films 2 and 2'. 4 is a glass plate for protecting the polarizing plate 1', 5 is a reflective plate made of aluminum foil, etc., and 6 is a sealing material for sealing the liquid crystal 3, for example, an epoxy adhesive is used. .

In the above liquid crystal display device, as shown in FIG. 2, numerous needle-like protrusions 7, 7' are formed on the surfaces of the transparent plastic films 2, 2' by sputter etching. A transparent electrode 8 is provided at a predetermined portion of the film 2.2'.
, 8' are provided.

Using a mixture of indium oxide and saponified tin for the transparent electrode 8.8'a, a thin film can be formed on the needle-like protrusion 7.7' by vacuum deposition, sputtering, or ion blating. From the point of view of uniform adhesion to the substrate, it is preferable to use a sputtering method or an ion blasting method. Note that when forming the transparent electrode, care should be taken to ensure that the thickness thereof is approximately 200 to 500, and that the shape of the needle-like protrusion is not substantially changed.

In such a liquid crystal display device, when a voltage is applied between the electrodes, a phase delay occurs, and a corresponding color change occurs in the transmitted light, and this color change enables color display.

The present invention is constructed as described above, and a liquid crystal is encapsulated so as to be vertically aligned in the darkness on the 11th side of a transparent plastic film on which numerous needle-like protrusions are formed by high-wavelength sputter etching treatment. Therefore, it has the characteristic that clear color display can be obtained.

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

Example: One side of a transparent film made of 37 chlorofluoroethylene resin having a thickness of 0.21111 was exposed to high waste waves using argon gas for 60 seconds under the conditions of an atmospheric pressure of 0.01 Torr and a discharge power density of I Wets/cs''. Sputter etching treatment (J
iii wave @ 13.56 MHz) L, average length 1
Forms countless needle-like protrusions.

Next, a mixture of indium oxide and tin oxide is formed on a predetermined part of the treated surface of this film to a thickness of 400 mm by sputtering to form a transparent electrode. -(P-Methoxybenzylidene) A liquid crystal containing P/-butylaniline as a main component was sealed using an epoxy adhesive to a thickness of 20 μm.

Then, place an orthogonal polarizing plate (thickness 10
A liquid crystal display device with the same structure was placed on a glass plate (500 μm thick) and a glass plate (500 μm thick), and an orthogonal polarizing plate (100 μm thick) and an aluminum foil reflector (5×11 m thick) on the other transparent film. Obtained.

When a voltage of 4 to 81 volts was applied between the transparent electrodes of this liquid crystal display device, color display ranging from yellow to green was achieved depending on the voltage.

For comparison, 4 to 8
When a voltage of V was applied, no change in color tone was observed and only black and white color display was possible.

) 4. Brief Description of the Drawings FIG. 1 is a cross-sectional view showing an example of a liquid crystal display device according to the present invention.

1.1'...Polarizing plate 2.2'...Transparent plastic film 3...m
A7.7'--Acicular projection patent applicant Nitto Electric Industry Co., Ltd. Representative Hijikata Sanbe

Claims (1)

[Claims] One side of the plastic film was etched with high-quality camphor to form fine needle-like protrusions, and two sheets of plastic film were placed so that the high-frequency sputter etching areas faced each other. A liquid crystal display device characterized in that a liquid crystal is sealed between the transparent plastic films and a polarizing plate is disposed on the other surface of the transparent plastic film.