JPH019935Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to a liquid crystal display element provided with means for suppressing abnormal lighting phenomena caused by static electricity.

<Prior Art> Conventionally, liquid crystal display elements have been widely used as small-sized, low-power-consumption displays. Among them, field-effect liquid crystal display elements (hereinafter referred to as TNFEM liquid crystal display elements) using twisted nematic liquid crystals are used for watches and
It occupies the mainstream of display devices such as calculators. FIG. 1 is a side cross-sectional view showing the schematic structure of a conventional TNFEM liquid crystal display. In the same figure, 1 and 1 are substrates such as glass,
2, 2 are display electrodes such as an ITO film coated on the substrates 1, 1 by vapor deposition, sputtering, etc.;
3, 3 is an alignment film coated on the display electrodes 2, 2, 4 is a spacer, 5 is a liquid crystal, 6 is a seal,
7, 7 is a polarizing plate provided on the outside of the substrates 1, 1, and 8 is a reflecting plate.

<Problems that the invention attempts to solve> However, the TNFEM with the above structure
In a liquid crystal display element, conventionally, when the surfaces of the polarizing plates 7, 7 are rubbed with a finger, cloth, etc., static electricity is generated, and the generated static electricity induces charging on the inner surfaces of the substrates 1, 1. If this charged charge is excessive, transparent electrodes 2, 2 on the inner surface of the substrates 1, 1
The liquid crystal molecules were excited by the electrical charging caused by the erroneous lighting.

The present invention was devised to solve the conventional problems caused by the generation of static electricity, and aims to prevent erroneous lighting of liquid crystal display elements by preventing excessive charging due to the generation of static electricity. This is the purpose.

<Means for Solving the Problems> The present invention provides a liquid crystal display element in which a liquid crystal is sandwiched between two substrates, in which at least one of the two substrates has a conductive material in a transparent material. It is a low-resistance substrate mixed with particles or a charge transfer complex, and is characterized in that the low-resistance substrate is grounded and a display electrode is formed on the low-resistance substrate via an insulating film.

<Function> According to the above, even if static electricity is generated on the surface of the polarizing plate, the charge is dispersed on the low resistance substrate, so that excessive charge charge does not occur locally, and the charge is transferred from the low resistance substrate into the air. static electricity is prevented.

<Example> Hereinafter, an example of the liquid crystal display element according to the present invention will be described in detail using the side cross-sectional view showing the schematic configuration of FIG. In FIG. 2, parts that are the same as those in FIG. 1 are designated by one reference numeral. In the figure, reference numerals 9 and 9 indicate low resistance substrates, and the low resistance substrates 9 and 9 are substrates made of transparent materials such as glass and plastic mixed with conductive particles such as metal particles and carbon particles (carbon black). Alternatively, it is a substrate made by mixing a charge transfer complex such as tetracyanoquinidimethane (TCNQ) or polysulfone nitride ((SN) ₂ ) into transparent plastic. Furthermore, at least one of the low resistance substrates 9, 9 is grounded. 10, 10 are insulating films such as SiO ₂ that insulate the inner surfaces of the low resistance substrates 9, 9. The substrates 9, 9 have a reduced resistance value due to the presence of the mixed material. This resistance value depends on the amount of mixed materials, but if the volume resistance value of the substrates 9 is 10 ⁸ Ωcm or less and the surface resistance value is 10 ⁸ Ω or less, excessive charging can be prevented. . The reason why this excessive charging can be prevented is that if the substrate has low resistance, even if static electricity is generated by rubbing the surface of the polarizing plates 7, 7 with a finger, cloth, etc., the charge will be dispersed on the substrate surface. No excessive charge charge occurs locally;
Even if the static electricity is generated, it is dissipated from the substrate surface into the outside air, so it is considered that the charge is difficult to accumulate on the substrate surface.

In addition, when a new low-resistance material (conductor) is installed, there may be a part around the display electrode where the low-resistance material is not present, and the display electrode may be charged with electric charge in this part, causing erroneous lighting. Sometimes I end up doing it. However, in the present invention, since the substrate itself is a low-resistance substrate for preventing static electricity, there is no place where there is no low-resistance material for the display electrodes, and it is possible to prevent charging of electric charges in all transparent electrodes.

Note that if the upper low resistance substrate 9 and the lower low resistance substrate 9 are electrically connected, the upper low resistance substrate 9 and the lower low resistance substrate 9 will have the same potential, so the insides of the substrates are approximately the same. Since the object is covered with a potential object, the effect of preventing static electricity is improved.

<Effects of the invention> As explained in detail above, according to the invention, by using a low-resistance substrate for the substrates that sandwich the liquid crystal layer, a low-resistance material for preventing static electricity can also be used as a substrate. Therefore, without adding a new low-resistance material, excessive charging due to static electricity does not occur on the electrodes in contact with the liquid crystal layer, and therefore, it is possible to provide a useful liquid crystal display element that can prevent abnormal lighting phenomena. It is.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing the schematic structure of a conventional TNFEM liquid crystal display element, and FIG. 2 is a side sectional view showing the schematic structure of an embodiment of the liquid crystal display element according to the present invention. 1...Substrate, 2...Display electrode, 3...Alignment film,
4... Spacer, 5... Liquid crystal, 6... Seal, 7
...Polarizing plate, 8...Reflector, 9...Low resistance substrate,
10...Insulating film.

Claims (1)

[Claims for Utility Model Registration] In a liquid crystal display element in which a liquid crystal is sandwiched between two substrates, at least one of the two substrates has conductive particles or a charge transfer complex mixed in a transparent material. 1. A liquid crystal display element, characterized in that the low resistance substrate is grounded and display electrodes are formed on the low resistance substrate via an insulating film.