JPH01213622A - Color liquid crystal display body - Google Patents

Abstract

PURPOSE:To facilitate electrode formation and cell thickness control and to improve characteristics by forming an adhesive layer on color filters formed on one substrate and forming transparent electrodes on a transparent substrate adhered thereon. CONSTITUTION:The color filters 3 are formed on the substrate 1 consisting of soda glass and the adhesive layer 4 is formed thereon by a roll coating method using an adhesive agent of a UV curing type. The low alkali glass substrate 8 is thereafter brought into tight contact with said layer and the fine bubbles in the adhesive layer 4 are expelled by using a rubber roller. UV rays are then projected on the low alkali glass substrate 8 from the front face side thereof to cure the adhesive layer 4. The surface of the low alkali glass substrate 8 is polished by a polishing machine to obtain the smooth surface. This substrate is cleaned and an electrode film consisting of ITO is formed by a vapor deposition method on the low alkali glass substrate 8 and is patterned to obtain the electrodes 6; further, an oriented film 7 is coated thereon. The color liquid crystal display body which has a uniform response speed and the good appearance of color tones is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a color liquid crystal display device used for a color display.

[Conventional technology]

Color liquid crystal displays using color filters are divided into those in which the color filter is formed outside the liquid crystal cell and those in which the color filter is formed inside the liquid crystal cell.

(Problem to be solved by the invention) Although the manufacturing process is simple for the color filter formed outside the cell, parallax occurs due to the thickness of the substrate on the color filter side, and the displayed color changes depending on the position of the viewer. There is a problem with the characteristics that are different. On the other hand, there are two types of cells in which a color filter is formed inside the cell: one in which the color filter is formed on the electrode, and one in which the color filter is formed between the electrode and the substrate. There is a characteristic problem in that the effective voltage applied to the liquid crystal drops, making it unsuitable for high duty. In addition, although the display characteristics of a color filter formed between the electrode and the substrate are excellent, it is difficult to form the electrode on the color filter, and the optimal film thickness varies depending on the base material of the color filter and the color of the filter. However, there were manufacturing problems such as the inability to make the cell thickness uniform.

The present invention was created in view of this problem, and its purpose is to take advantage of the advantages of the color liquid crystal display in which a color filter is formed between the electrodes and the substrate as described above, and to facilitate electrode formation and cell thickness management. The objective is to provide a color liquid crystal display that can be used.

(Means for Solving the Problems) The color liquid crystal display of the present invention comprises a liquid crystal sandwiched between a pair of substrates, at least one of which is transparent, and a color liquid crystal formed on one substrate and between the liquid crystal. A color liquid crystal display having a filter, a color filter formed on the one substrate, an adhesive layer formed to cover the entire surface of the color filter, and a transparent substrate adhered onto the adhesive layer. and a transparent electrode is formed on the substrate.

(Function) FIG. 4 shows a sectional view of a color filter forming side substrate (hereinafter referred to as a color filter substrate) of a typical conventional color liquid crystal display, and a color filter substrate of a typical color liquid crystal display of the present invention. A cross-sectional view of the color filter is shown in FIG. 1. In FIG. 4 and FIG. 1, an undercoat layer 2 is formed on the substrate 1 in order to improve the adhesion of the color filter, the effect of preventing ion elution, and other properties. The undercoat layer 2 does not need to be one layer, and may include, for example, a layer for preventing ion elution,
A layer for improving the adhesion of the color filter may be laminated, and then the color filter 3 is formed on the undercoat layer 2. Methods for forming the color filter 3 include printing methods, dyeing methods, etc., but the optimal film thickness for a liquid crystal display differs depending on the color (for example, red, green, blue, etc.). Thereafter, in the conventional color filter substrate, after forming the overcoat layer 11 as shown in FIG. 4, the electrodes 6 are formed.

The overcoat layer 11 is preferably made of a material that protects the color filter 3, improves the adhesion of the electrode 6, and protects the edges of the color filter 3.The overcoat layer 11 is a combination of an organic film and an inorganic film. A multilayer film is suitable. In addition, in order to smooth out the unevenness of the color filter 3 and the depressions in the gap portion with the overcoat layer 11, a fairly thick overcoat layer 11 is required, or in that case, it is difficult to make the thickness of the overcoat layer 11 uniform. Therefore, it is difficult to make the surface of the color filter 3 smooth. After that, the electrode 6 is formed and the rough orientation 1 is formed.
17 are formed.

- In the power tree invention, as shown in Fig. 1, the color filter 3
An adhesive layer 4 is formed thereon, and a transparent substrate 5, at least one of which has been polished, is adhered to the color filter 3 through the adhesive layer 4. In manufacturing, there are two methods: bonding a pre-polished transparent substrate 5, and bonding and then polishing the transparent substrate 5, but either method is fine. However, this may be either a method in which it is formed on the transparent substrate 5 in advance and then bonded, or a method in which it is formed after the transparent substrate is bonded.

The transparent substrate 5 used in the present invention is desirably as thin as possible due to parallax problems, and the material may be either organic or inorganic, but an inorganic material with a low alkali ion content such as low alkali glass may be used as an undercoat. The layer 2 may be omitted, and in this case, the adhesion of the electrode 6 is also improved. When forming the adhesive layer 4, if it is thicker than the color filter 3, the unevenness of the color filter 3 will be smoothed by the adhesive layer 4. Furthermore, a layer for protecting the color filter may be provided between the adhesive layer 4 and the color filter.

As described above, the color liquid crystal display of the present invention has fewer restrictions in manufacturing and has improved characteristics compared to conventional color liquid crystal displays. Hereinafter, it will be explained in detail using examples.

(Example 1) As shown in FIG. 2, a color filter 3 was formed on a substrate 1 made of soda glass, and an adhesive layer 4 was formed using an ultraviolet curing adhesive by a roll coating method. After that, a low alkali glass substrate 8 with a thickness of 0.1 mm was attached closely, and ultraviolet rays were irradiated from the top side of the zero-order low alkali glass substrate 8, which removed fine air bubbles in the adhesive layer 4 using a rubber roller. 'lIi adhesion layer 4 was cured and the surface of the low-alkali glass substrate 8 was polished using a polishing machine to obtain a smooth surface. Next, this was cleaned and a layer made of ITO was placed on the low-alkali glass substrate 8. A telephone pole film was formed by vapor deposition, patterned to obtain an electrode 6, and an oriented layer 7 made of polyimide was applied thereon to produce a color filter substrate for a liquid crystal display. When this was used to form a cell for a liquid crystal display, and the cell was connected to a drive circuit and driven, a color liquid crystal display with uniform response speed, uniform color tone, and good appearance was obtained.

(Comparison example) On the other hand, in the conventional color liquid crystal display shown in Figure 4, which was created for comparison, the spacer material for maintaining the liquid crystal cell gap sinks into the color filter on the substrate, resulting in uniform cell thickness. This appeared as a difference in response speed. Also, due to poor adhesion between the electrode 6 and the overcoat layer 11, some of the electrodes were cut off, resulting in electrodes that could not be applied with voltage.

(Example 2) A color liquid crystal display similar to that of Example 1 was prepared using liquid crystal mixed with black dye, and compared with a color liquid crystal display prepared by the conventional method shown in FIG. 4, which was prepared for comparison. Did 0
The color liquid crystal display of this example was prepared using black dye in Example 1.
However, in conventional color liquid crystal displays, the effect of black dye varies from color filter to color filter due to variations in cell thickness, and furthermore, due to variations in overall cell thickness, The liquid crystal cell became optically non-uniform, resulting in poor viewing.

(Example 3) As shown in FIG. 3, a color filter 3 was formed on a substrate l made of sorter glass to obtain a substrate A.

On the other hand, after polishing a soda glass substrate 9 with a thickness of 0.1 mm, an SiO3 film 1O for preventing the elution of alkali ions and an electrode 6 made of ITO were formed by sputtering, and an alignment film 7 was coated to form the substrate B. And so. After that, the substrate A and the substrate B were sandwiched between the adhesive layer 4 made of a V-curing adhesive, and when the adhesive layer 4 was cured by irradiation with ultraviolet rays, the surface of the substrate 8 remained smooth and bonded. When a liquid crystal cell was formed using the substrate prepared in Example 1 and was connected to a drive circuit and driven, a color liquid crystal display with good appearance similar to that shown in Example 1 was obtained.

As an effect of this embodiment, since the substrate on which the color filter is formed and the substrate on which the electrodes made of ITO are formed are separate bodies, it is possible to process each of them. Therefore, there is an effect that there is no longer a restriction that high temperatures cannot be applied when forming electrodes on a substrate on which a color filter has already been formed, as in the prior art. Furthermore, since each material can be processed as described above, it is possible to lower the resistance of the electrode by high temperature heating or the like when forming the electrode.

(Effects of the Invention) As described above, according to the present invention, it is possible to provide a substrate with a hard surface and less irregularities for use in a color liquid crystal display than the conventional method. Further, it is easy to form a color liquid crystal display, and the same electro-optical properties as a liquid crystal display without a color filter layer can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of the color filter side substrate of the color liquid crystal display of the present invention. FIG. 2 is a sectional view of a color filter side substrate of a color liquid crystal display for explaining Examples 1 and 2 of the present invention. FIG. 3 is a cross-sectional view of a color filter side substrate of a color liquid crystal display explaining Example 3 of the present invention. FIG. 4 is a sectional view of a color filter side substrate of a conventional color liquid crystal display. l... Substrate 2... Undercoat layer 3... Color filter 4... Adhesive layer 5... Transparent substrate 6... Electrode 7... Alignment film 8... Low alkali glass substrate 9 ...Leader glass substrate 10φ...SiO*M 11...Overcoat layer and above Applicant Seiko Epson Corporation Fig. 1 Fig. 2

Claims (1)

[Claims] A color liquid crystal display having a liquid crystal sandwiched between a pair of substrates, at least one of which is transparent, and a color filter formed on one of the substrates and between the liquid crystal,
It has a color filter formed on the one substrate, an adhesive layer formed to cover the entire surface of the color filter, and a transparent substrate adhered on the adhesive layer, and a transparent substrate is formed on the substrate. A color liquid crystal display characterized by forming electrodes.