JPS62134626A - Structure for arranging spacer material in liquid crystal display body - Google Patents

Abstract

PURPOSE:To control precisely the inter-substrate gap to improve the display quality and the yield considerably by making the distribution density of spacer materials for the gap different between the center part and the peripheral part and arranging spacer materials in parts other than center parts of picture elements. CONSTITUTION:The distribution density of spacer materials 10 for the gap between upper and lower substrates is varied, and preferably, a ratio of distribution density of spacer materials near a seal to that in the center part of the displays body is set to 1:(1-10). Spacer materials 10 are arranged in gaps of picture elements or near end faces of them. Though the gap between substrates in the center part of the cell is apt to be narrower than that near the seal, the gap is controlled precisely because the distribution density of spacer materials is varied. Though characteristics are degraded by irregular reflection if spacers exist in center parts of picture elements, spacer materials are arranged in parts other than center parts to improve the display characteristic and the yield considerably.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the arrangement of spacer materials for the gap between the upper and lower substrates of a liquid crystal display.
Regarding structure.

[Summary of the invention]

The present invention makes a difference in the distribution density of the spacer material for the gap between the upper and lower substrates of a liquid crystal panel to ensure a uniform gap between the substrates. By making a difference in the range of 10 and arranging the spacer material in the gap between the pixels or near the end face thereof, the gap between the upper and lower substrates can be precisely controlled, and the display quality can be greatly improved.

[Conventional technology]

Conventional spacer materials for the gap between the upper and lower substrates of liquid crystal displays include glass fiber, alumina oxide, metal oxides such as 5in2 crystal balls, polystyrene, polyamide, epoxy resin, acrylic resin, polyester, polyamide, acrylic, and gelatin. A photosensitive polymer resin such as the following is used, and the shape thereof is cylindrical or spherical. There are two ways to apply the spacer material: a dry method in which the spacer material is placed on a sieve and sprinkled with vibration or compressed air, and a wet method in which the spacer material is mixed in a volatile organic solvent and spread by spraying. Further, there are printing methods in which the spacer material is formed by photo-buttering, photo-etching, screen printing, offset printing, flexographic printing, and the like. In all conventional methods, the gap between the substrates is made uniform by uniformly arranging spacer materials in equal amounts within cells, and the key point is to make the number of spacer materials uniform per unit area. However, the conventional method has problems in that it is difficult to control the gap between the upper and lower substrates, and the poor Ei gap causes panel discoloration, poor appearance, poor contrast, and poor response, resulting in poor display quality and yield.

The present invention is intended to solve this problem, and its purpose is to provide a technique for precisely controlling the gap between upper and lower substrates in order to improve display quality and yield.

[Means to solve the problem]

The arrangement structure of the spacer material for the gap between the upper and lower substrates of the liquid crystal display of the present invention is to control the gap between the substrates by making a difference in the distribution density of the spacer material within the cell, and the spacer material is arranged in the vicinity of the sealing area of the display body and in the center area. Spacer material distribution density ratio of 1:1
By making a difference in the range of 10, the gap can be controlled with high precision. Another feature is that the display characteristics are improved by arranging the spacer material in the pixel gap or near the end face thereof.

[Effect]

According to the above configuration of the present invention, as the cell size of the liquid crystal display becomes larger or the substrate thickness becomes thinner, and the gap between the upper and lower substrates becomes thinner, the gap at the center of the cell tends to become lower than that at the time of sealing. Therefore, instead of arranging the spacer material uniformly within the cell as in the past, by creating a difference in the density of the spacer material at the center and at the time of sealing, the gap between the substrates can be precisely controlled. Furthermore, if the spacer material is located at the center of the pixel, it will diffusely reflect light and the optical characteristics will deteriorate. Therefore, by arranging the spacer material between the pixels or near the end faces of the pixels, display characteristics can be improved.

〔Example〕

FIG. 1 is a cross-sectional view of a liquid crystal panel in an embodiment of the present invention;
FIG. 2 is a layout diagram of spacer materials in an embodiment of the present invention. Spacer material 10 for the gap between upper and lower substrates in the present invention
The distribution density of is characterized by being less at the seal edge, more at the center of the cell, and more at the pixel gap or near its end face.

This will be explained in detail in Examples below.

Example-1 Glass fiber of 8 μm was used as the spacer material for the substrate gap, and the density of the spacer material in the vicinity of the seal and in the center was 1 = 5.
A spacer material was fried on the surface of the substrate using compressed air using a sieve, and after cell formation, TN type liquid crystal was injected. The substrate gap was improved by about 10% compared to the conventional product, and the display characteristics were also good.

Example-2 Polyamide resin is used as the substrate gap spacer material, φ15μ
m, thickness 2 μm, printed by offset printing with a difference in spacer material distribution density of 1:2 between the seal part and the center part,
After annealing, alignment treatment was performed to form cells, and smectic liquid crystal was injected. The accuracy and variation in the gap between the upper and lower substrates were improved by 10 to 20% compared to conventional products, and the display characteristics were also excellent.

Example-5 Using gelatin photosensitive resin as the spacer material for the substrate gap, the width is 15 μm, the length is 25 μm square, and the thickness is 2 μm.The spacer material distribution density is divided into three parts from the sealing side to the center, in a ratio of 1:2:3. After performing 7-dimensional patterning with a difference, annealing was performed to form a cell, and a smectic liquid crystal was injected. The accuracy and variation of the gap between the upper and lower substrates and the display characteristics were also comparable to those of Example-2.

Example-4 Using photosensitive polyamide resin as the spacer material for the substrate gap,
A door with a diameter of 15 μm and a thickness of 1.5 μm is divided into three parts from the spacer material distribution density seal to the center, with a difference in the ratio of 1:2:3. After forming a pattern near the pixel gap, annealing and alignment treatment are performed. It was made into a cell and injected with smectic liquid crystal. The accuracy of the gap between the upper and lower substrates has been improved, the gap has become extremely uniform, and the number of defective substrate gaps and pixel defects has been greatly reduced, greatly improving display quality.

〔Effect of the invention〕

As described above, according to the present invention, the distribution density of the spacer material for the gap between the upper and lower substrates of the liquid crystal panel is differentiated, and preferably the distribution density ratio between the vicinity of the sealing edge and the central part of the display is in the range of 1:1 to 10. By making a difference in the distance between the pixels and arranging the spacer material in the gap between the pixels or near the edge thereof, the accuracy and uniformity of the gap between the upper and lower substrates can be greatly improved, and the display characteristics and yield can be greatly improved. Although the invention has been described with respect to a liquid crystal display, it can be applied to other displays such as FCD and EP, which aim to improve display quality by keeping the gap between two or more substrates constant, and is highly effective.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the liquid crystal display of the present invention. FIG. 2 is a plan view showing the arrangement of spacer materials in FIG. 1. FIG. 3 is a cross-sectional view of a conventional liquid crystal display. FIG. 4 is a plan view showing the arrangement of the spacer materials shown in FIG. 3. 1... Upper transparent substrate 2... Lower Komei substrate 5... Upper transparent electrode 4... Lower transparent electrode 5...Liquid crystal layer 6...Upper polarizing plate 7...Lower polarizing plate 8...・Sealing agent 9...Sealing agent spacer material 10...
...More than spacer material for the gap between the upper and lower boards

Claims (3)

[Claims] (1) A liquid crystal display that secures the gap between the substrates by making a difference in the distribution density of the spacer material for the gap between the upper and lower substrates. (2) A liquid crystal display according to claim 1, wherein the substrate gap is secured by making a difference in the distribution density ratio of the spacer material in the vicinity of the sealing edge of the display body and in the center part in the range of 1:1<10. body. (3) The liquid crystal display according to claim 1, characterized in that the spacer material is arranged between the pixels or near the end faces of the pixels.