JP2002156518A - Method for manufacturing color filter substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a color filter substrate preventing residual air bubbles from being generated in a liquid crystal cell after sealing a liquid crystal therein without canceling an advantage of a method for manufacturing a liquid crystal display device using a dripping method, i.e., without extending evacuation time for sticking the color filter substrate to a counter substrate. SOLUTION: Prior to formation of the liquid crystal cell, the color filter substrate is set up in a thermostat under atmospheric pressure, is heated to a specified temperature, furthermore, is kept at the specified temperature for a specified time, subsequently is returned to normal temperature and is subjected to degassing treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a color filter substrate used for a liquid crystal display device.

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices capable of color display, that is, devices having color filters, have become mainstream due to diversification of functions of personal computers and word processors equipped with the liquid crystal display devices.

FIG. 3 shows a general color filter substrate. FIG. 4 shows a general liquid crystal display device.

First, FIG. 3 will be described. A color filter 6 is formed on a substrate 5, and a protective film 7 is formed so as to cover the entire surface of the color filter 6. Then, a transparent electrode 8 is formed via the protective film 7, and an insulating film 9 is formed so as to cover the entire surface of the transparent electrode 8 and the protective film 7, thereby forming the color filter substrate 4.

A liquid crystal display using the color filter substrate 4 is configured as shown in FIG. First, substrate 1
4, a transparent electrode 8 and an insulating film 9 are sequentially laminated to form a counter substrate 15.

The orientation control film 10 is provided on each of the counter substrate 15 and the color filter substrate 4 constructed as described above.
Is formed, the color filter substrate 4 and the opposing substrate 15 are opposed to each other with the spacer 11 interposed therebetween, and are bonded together with the sealant 12 to form a liquid crystal cell.

[0007] Then, liquid crystal 13 is injected into the inside of the liquid crystal cell to form a liquid crystal display device 16.

[0008]

In the liquid crystal display device 16 having such a color filter substrate 4, the pressure reduction state when the liquid crystal 13 is sealed and the subsequent alignment control film 1
Gas is easily generated from the color filter 6 and the protective film 7 by heat treatment or the like at the time of stabilizing the orientation of 0. When gas is generated from the color filter 6 and the protective film 7, residual bubbles are generated in the liquid crystal cell after the liquid crystal 13 is sealed,
The liquid crystal display device 16 has a problem of causing a fatal defect.

For this reason, Japanese Patent Application Laid-Open No. 4-42129 discloses that before injecting liquid crystal into a liquid crystal cell, the liquid crystal cell is degassed by holding the liquid crystal cell under reduced pressure and heating for a long time, and after the liquid crystal is sealed. A method for preventing residual air bubbles is disclosed.

However, this method is disclosed in Japanese Patent Laid-Open No. 62-8 / 1987.
It is not suitable for the dropping method disclosed in Japanese Patent Application Laid-Open No. 9025 or JP-A-63-179323. That is, in the dropping method, a predetermined amount of liquid crystal is dropped on at least one of the color filter substrate and the counter substrate, and both substrates are bonded together under reduced pressure, and cell formation and liquid crystal encapsulation are simultaneously performed.

Therefore, if the above-described method of holding the liquid crystal cell before injecting the liquid crystal 13 under reduced pressure and heating for a long time is used in such a dropping method, the two substrates can be formed into a liquid crystal cell in a short time. There was a problem that the advantage of the law was lost.

In view of the above problems, the present invention does not impair the advantages of the method of manufacturing a liquid crystal display device by a dropping method,
Provided is a method of manufacturing a color filter substrate capable of preventing generation of residual bubbles in a liquid crystal cell after sealing a liquid crystal without extending a vacuum holding time at the time of bonding a color filter substrate and a counter substrate. Things.

[0013]

According to a method of manufacturing a color filter substrate of the present invention, before forming a liquid crystal cell, the color filter substrate is subjected to degassing by heating at atmospheric pressure in a constant temperature bath. Features.

According to the method for manufacturing a color filter substrate of the present invention, the degassing process is performed before the liquid crystal cell is formed. Under the same conditions, generation of residual bubbles in the liquid crystal cell after the liquid crystal is sealed can be prevented. Further, the time required for degassing the color filter substrate can be further reduced.

[0015]

According to a first aspect of the present invention, there is provided a method for manufacturing a color filter substrate, wherein the color filter substrate is installed in a constant temperature bath under atmospheric pressure, heated to a predetermined temperature, and further maintained at the predetermined temperature for a predetermined time. After that, degassing is performed by opening to normal temperature.

According to this structure, the color filter substrate alone is placed under atmospheric pressure in a constant temperature bath, heated to a predetermined temperature and degassed, so that the upper limit of the heating temperature is set to the heat resistant temperature of the color filter substrate. Can be set, so that the degassing process can be performed in a short time. Therefore, when the liquid crystal is encapsulated by the dropping method using the color filter substrate treated by the above method, the liquid crystal can be filled without extending the vacuum holding time at the time of encapsulation, that is, without impairing the advantage of the dropping method. Can prevent the generation of residual air bubbles in the liquid crystal cell after the sealing. Furthermore, since the degassing process is performed under the atmospheric pressure, the degassing process can be performed in a shorter time without the need for evacuation time as compared with the case where the degassing process is performed under reduced pressure. No equipment is required. When manufacturing a color filter substrate using a large substrate, the temperature chamber itself becomes large, and it takes a very long time to evacuate, so degassing under atmospheric pressure is a significant manufacturing process. It leads to shortening of tact.

According to a second aspect of the present invention, in the method for producing a color filter substrate according to the first aspect, the heating temperature is set to be higher than 150 ° C.
C., and the holding time of the heating temperature is longer than 6 hours and shorter than 12 hours.

According to this configuration, good degassing of the color filter substrate can be realized.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4 showing the above-mentioned conventional example are denoted by the same reference numerals and described.

(Embodiment) FIG. 1 is a diagram showing a flow of a method for manufacturing a liquid crystal display device using the method for manufacturing a color filter substrate of the present invention. On the color filter substrate side, the color filter substrate 4 as shown in FIG. 3 described above is formed in a first step A1.

In a second step A2, the color filter substrate 4 is placed alone in a thermostat such as a clean oven under atmospheric pressure, heated to a predetermined temperature, and held for a predetermined time.
The color filter substrate 4 is degassed.

FIG. 2 shows an apparatus for degassing the color filter substrate 4. The color filter substrate 4 is placed under atmospheric pressure on a substrate holder 3 provided inside the thermostat 1. Then, the color filter 6 is degassed by heating to a predetermined temperature by the heater 2 and holding the same for a predetermined time and then opening the room temperature.

In the degassing process, in the case of the color filter substrate 4 having the polyester resin color filter 6 and the acrylate resin protective film 7, the heating temperature is higher than 150 ° C. and lower than 180 ° C. By setting the holding time to be longer than 6 hours and shorter than 12 hours, good degassing of the color filter 6 and the protective film 7 can be realized. If the temperature range and the processing time deviate, sufficient degassing cannot be performed.

In the third step A3, an orientation control film 10 is formed on the color filter substrate 4 which has been subjected to the degassing process, a sealing material 12 is applied, and a cell surrounded by the sealing material 12 is placed in a region to be a cell. A fixed amount of liquid crystal 13 is dropped.

On the other hand, on the side of the opposing substrate, a fourth step A4
Then, similarly to FIG. 3 showing the above-mentioned conventional example, the transparent electrode 8 and the insulating film 9 are formed on the surface of the substrate 14, and the counter substrate 15 is formed.

Then, in a fifth step A5, the opposite substrate 1
5, an alignment control film 10 is formed. In the sixth step A6, spacers 11 are scattered on the opposing substrate 15 using the color filter substrate 4 and the opposing substrate 15 formed as described above, and the color filter substrate 4 on which the liquid crystal 13 is dropped is reduced under reduced pressure. Then, the sealing material 12 is cured to form the liquid crystal display device 16.

According to the method of manufacturing the liquid crystal display device, since the color filter substrate 4 is subjected to the heat treatment in advance in the second step A2, degassing from the color filter is considered in the steps after the second step. You don't have to.
Therefore, in the liquid crystal sealing step of the sixth step A6, both substrates can be made into liquid crystal cells in a short time without extending the vacuum holding time, that is, when the dropping method is used.
The generation of residual air bubbles in the liquid crystal cell can be prevented without impairing the advantage of the above.

Although the heat treatment of the color filter substrate 4 is performed after the formation of the insulating film 9 in this embodiment, it may be performed before the formation of the insulating film 9. Alternatively, it may be performed after the alignment control film 10 is formed.

In this (embodiment), the sealing material 1
Although the application of 2 and the dropping of the liquid crystal 13 are performed on the color filter substrate 4 side, the same effect can be obtained by performing on the counter substrate 15 side.

[0030]

As described above, according to the method for manufacturing a color filter substrate of the present invention, the upper limit of the heating temperature can be set up to the heat resistant temperature of the color filter substrate, so that the degassing process can be performed in a short time. Therefore, it is possible to prevent the generation of residual air bubbles in the liquid crystal cell after sealing the liquid crystal without extending the vacuum holding time at the time of bonding the color filter substrate and the opposing substrate. Since gas processing is performed, degassing processing can be performed in a shorter time without requiring time for evacuation.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a manufacturing process of a liquid crystal display device in Embodiment.

FIG. 2 is a view showing a degassing process of a color filter substrate in the embodiment.

FIG. 3 is a view showing a general color filter substrate;

FIG. 4 is a diagram showing a general liquid crystal display device.

[Explanation of symbols]

 Reference Signs List 4 color filter substrate 5 substrate 6 color filter 15 counter substrate 16 liquid crystal display

Claims (2)

[Claims] 1. A color filter substrate is placed in a thermostatic chamber under atmospheric pressure, heated to a predetermined temperature, held at the predetermined temperature for a predetermined time, then released to normal temperature and degassed. Manufacturing method of a color filter substrate. 2. The degassing process of the color filter substrate, wherein the heating temperature is higher than 150 ° C. and lower than 180 ° C., and the holding time of the heating temperature is longer than 6 hours and less than 12 hours. 2. The method for manufacturing a color filter substrate according to 1.