JPS6370803A - Formation of color filter - Google Patents

Abstract

PURPOSE:To simplify processes and to shorten working time by subjecting a substrate to a resist treatment by immersion into a fixing liquid to eliminate the need for executing photoetching again after the resist treatment. CONSTITUTION:A dyeable photosensitive resin 12 is coated by means such as spin coating on a transparent substrate 11 such as glass. The dyeable photosensitive resin 2 is prebaked by heating and a photomask is put thereon. The resin is then exposed, developed and post-baked, by which the dyeable photosensitive resin 12 is patterned. The substrate 11 is immersed in dye water to color the dyeable photosensitive resin 12. The substrate 11 is further subjected to the resist treatment by immersion into the fixing liquid 13. The resist treatment is executable by the process consisting in immersing the substrate into an aq. tannic acid soln. (60-70 deg.C) for about 1min and washing the substrate, then immersing the substrate in an aq. tartaric acid soln. (40-60 deg.C) for about 1min followed by washing. The process is thereby simplified and the film thickness is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for forming a color filter applied to, for example, a liquid crystal display element.

"Prior Art and its Problems" For example, in liquid crystal display devices and the like, devices in which color filters are formed on a glass substrate are used. Special
In some devices, such as color liquid crystal televisions, a large number of pixel electrodes are provided, and color filters of three primary colors are provided corresponding to each pixel electrode.

To give an example of a conventional method for forming such a color filter, as shown in FIG.
Next, the dyeable photosensitive resin 2 is covered with a photomask, exposed and developed, and patterned as shown in FIG. 2(b). This is immersed in an aqueous dye solution to dye the patterned dyeable photosensitive resin 2 as shown in Figure 2 (C). Finally, the resist dyeing resin 3 is applied to the surface of the dyeable photosensitive resin 2 by means such as a spin cord, and resist dyeing treatment (processing to prevent dye bleeding and fading) is performed.

However, in the conventional color filter forming method described above, in the case of, for example, a liquid crystal display element, the resist dyeing resin 3 is also applied to the terminal part, so a process of scraping and photoetching the resist dyeing resin 3 is required. , the manufacturing process was becoming more complex. Further, since the resist dyeing treatment is performed by applying the resist dyeing resin 3, the color filter tends to become thicker due to the resisting resin 3. In particular, in the case of color LCD TVs, etc., it is necessary to provide three types of color filters that make up the three primary colors, so the process as described above @ 3 times is repeated.
Color filters are formed for each color, but in that case, the resist dyeing resin 3 has to be applied three times, resulting in an extremely thick film of the color filter. In the case of liquid crystal display elements, a behavior W in which the alignment of liquid crystals is disturbed due to color filters may occur.

OBJECT OF THE INVENTION In view of the problems of the prior art described above, an object of the present invention is to provide a method for forming a color filter in which the process is further simplified and the film thickness can be reduced.

"Structure of the Invention" The method for forming a color filter according to the present invention includes a step of applying a dyeable photosensitive resin onto a substrate or a thin film formed on the substrate, and a step of patterning the dyeable photosensitive resin by photoetching. , a step of dyeing the dyeable photosensitive resin by immersing it in dye water, and a step of applying resist dyeing treatment by immersing it in a fixing liquid.

As described above, in the present invention, since the resist dyeing treatment is performed by immersing in the fixing liquid, there is no need to perform photoetching again after the resist dyeing treatment, which simplifies the manufacturing process. In addition, since resist dyeing treatment is applied without applying resist dyeing resin,
Accordingly, the film thickness of the color filter can be made thinner, and when applied to a liquid crystal display element, etc., there is no risk of deterioration of characteristics.

"Embodiment of the Invention" FIG. 1 shows an embodiment of the method for forming a color filter according to the present invention.

As shown in FIG. 1(a), a transparent substrate 11 such as glass
A dyeable photosensitive resin 12 is applied thereon by means such as a spin cord. As the dyeable photosensitive resin 12, for example, acrylic resin "rR603" (trade name, manufactured by Nippon Kayaku ■) can be used. Note that the film thickness of the dyeable photosensitive resin 12 is suitably about 0.7 to 0.8 um.

As shown in FIG. 1(b), the dyeable photosensitive resin 12 is heated and prebaked, covered with a photomask, exposed, developed, and postbaked to pattern the dyeable resin 1218.

As shown in FIG. 1C, the substrate 11 is immersed in dye water to color the dyeable photosensitive resin 12 that has been patterned.

In this case, as a red dye, for example, rR21PJ or 'R+36PJ (trade name, manufactured by Nippon Kayaku tI@) can be used, and a blue dye, for example, r
B43PJ, '87PJ (trade name, manufactured by Nippon Kayaku ■) can be used, and as a green type, for example, rGIP J
, 'G7PJ (product name, manufactured by Nippon Kayaku ■) can be used.

As shown in Fig. 1 (d), the substrate 11 is immersed in the fixing liquid 13 to perform resist dyeing treatment. When the above dye is used as the staining agent, this resist staining treatment is performed using ■ Tannic acid aqueous solution (60%
- 70°C) for about 1 minute, (1) washing with water, (2) immersing in an aqueous tartaric acid solution (40 - 60°C) for about 1 minute, and (4) washing with water.

The color filter thus obtained can be formed to have a total thickness of 0.68 to 1.5 μm. On the other hand, in the conventional forming method shown in FIG. 2, the total film thickness is 1.5 to 3.0 um.

Note that when applying the color filter forming method of the present invention to, for example, a color liquid crystal display television, a pixel electrode made of a transparent conductive film is formed on the substrate 11, and the above steps are repeated three times to form a predetermined shape. Color filters made of three primary colors of red, blue, and green are formed corresponding to the pixel electrodes. In this case, since color filters of different colors are rarely stacked, the total film thickness is the film thickness of each color filter, that is, 0.8 to 1.5
It is possible to make it about um. Then, an alignment film made of polyimide resin may be formed over this color filter.

"Effects of the Invention" As explained above, according to the present invention, since the resist dyeing treatment is performed by immersion in the fixing liquid, there is no need to perform photoetching again after the resist dyeing treatment, and the process is simplified. can be used to reduce work time. Further, since the resist dyeing treatment can be performed using an inexpensive fixing liquid, manufacturing costs can also be reduced. In general, since resist dyeing treatment is performed without applying resist dyeing resin, the film thickness of the color filter can be made thinner, and there is no risk of degrading the characteristics when applied to a liquid crystal display element or the like. In addition, since resisting treatment can be performed simply by immersing the material in a fixing solution, it becomes easier to manage various conditions.

[Brief explanation of the drawing]

Figure 1(a), Figure 1(b), Figure 1(C), Figure 1(
d) is a sectional view showing an embodiment of the method for forming a color filter according to the present invention according to the steps; FIG. 2(a), FIG. 2(b);
), FIG. 2(C), and FIG. 2(d) are cross-sectional views showing an example of a conventional color filter forming method according to the steps. In the figure, 11 is a substrate, 12 is a dyeable photosensitive resin, and 13 is a fixing liquid.

Claims (2)

[Claims] (1) A process of coating a dyeable photosensitive resin on the substrate or a thin film formed on the substrate, a process of patterning the dyeable photosensitive resin by photoetching, and a process of patterning the dyeable photosensitive resin by immersing it in dye water and exposing it to the dyeable photosensitive resin. A method for forming a color filter, comprising the steps of dyeing a resin and applying resist dyeing treatment by immersing it in a fixing liquid. (2) The method for forming a color filter according to claim 1, wherein the step of applying resist dyeing treatment comprises the steps of immersing in an aqueous tannic acid solution and immersing in an aqueous tartaric acid solution.