JPH05173013A - Color filter manufacturing method - Google Patents

Abstract

(57) [Abstract] [Purpose] There is no risk that a part of another unit color filter will be formed on the unit color filter created earlier, and the surface of the color filter can be smoothed. The viewing angle characteristics of the liquid crystal display device can be greatly improved, defects such as overedges at the time of patterning the ITO electrode on the surface can be prevented, and the manufacturing process can be simplified. [Structure] An ultraviolet ray that applies a remaining colored resist of one color to a substrate on which a filter of at least one color is partially formed, and blocks light in the ultraviolet side transmission wavelength range of the filter of the photosensitive wavelength range of the colored resist. The feature is that back exposure is performed by ultraviolet rays through a cut filter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color filter used in a liquid crystal display device or the like.

[0002]

2. Description of the Related Art As a conventional method of manufacturing a color filter of this kind, as shown in FIG. 3, for example, a metal such as Cr is sputtered on a transparent substrate 1 such as a glass substrate through a mask. Or, a light-shielding resist made of an organic substance is applied, a mask is placed, and ultraviolet rays are radiated. The light-shielding film 2 is formed in a grid pattern on the portions other than the portions corresponding to each pixel, leaving the portions exposed to the ultraviolet rays ( FIG. 3 (a)),
After that, corresponding to each pixel, for example, red R, green G, blue B
There is a method of forming the unit color filters 3a, 3b, and 3c (see FIG. 3B), that is, a method using a so-called mask.

Further, as shown in FIG. 4, on the transparent substrate 1 such as a glass substrate, unit colors of R, G, B corresponding to each pixel by dyeing, pigment dispersion, electrodeposition method or the like. The filters 3a, 3b, 3c are formed (FIG. 4A), and then
By applying a light-shielding resist 4 (FIG. 4 (b)) and performing back exposure with ultraviolet rays, the portions exposed by the ultraviolet rays are left without being shielded by the unit color filters 3a, 3b, 3c. There is a method of forming the light shielding film 2 between 3c (FIG. 4C), a so-called self-alignment method.

[0004]

However, in any of the above methods, the unit color filter 3a corresponding to each pixel,
Since the step of forming the light shielding film 2 separately from 3b and 3c is required, there is a problem that the manufacturing process is complicated.

In any of the above methods, the light shielding film 2
Is formed thinner than the unit color filters 3a, 3b, 3c, so that the surface becomes non-uniform, which is a serious problem for the STN liquid crystal display device in which the viewing angle characteristics deteriorate unless the surface is smooth. Further, if the surface is non-uniform, there is a problem that defects such as overedges are likely to occur during patterning of the ITO electrode on the surface.

Therefore, in order to solve the above-mentioned problems, as shown in FIG. 5, for example, R, R, etc. corresponding to each pixel are dyed on the transparent substrate 1 such as a glass substrate by dyeing, pigment dispersion, electrodeposition or the like. G unit color filters 3a and 3b are formed, and then the remaining one color B of colored resist 5 is applied (see FIG.
(A)), back exposure with ultraviolet rays (FIG. 5 (b)), and leaving the portions exposed to ultraviolet rays without being blocked by the unit color filters 3a and 3b, the unit color filter 3
A method has also been proposed in which the unit color filter 3c of B is formed between a and 3b together with the light shielding film (FIG. 5C).

However, in the case of this method, in addition to the transmission wavelength range of the B filter, the wavelength range of the B colored resist is R.
Alternatively, the ultraviolet side transmission wavelength range of the G filter (R or G
The second transmission peak of the filter, which varies depending on the material and thickness of the filter. ) Is also included, and in this case, as shown in FIG. 5C, the colored resist of B is exposed even behind the unit color filter 3a of R previously created, As a result, there is a problem that a part 3c 'of the B unit color filter 3c is formed on the R unit color filter 3a in an overlapping manner.

In view of the above problems, the present invention eliminates the possibility that a part of another unit color filter is formed on the previously prepared unit color filter, and
The surface of the color filter can be smoothed, the viewing angle characteristics of the STN liquid crystal display device can be greatly improved, and defects such as overedges when the ITO electrode is patterned on the surface can be prevented. It is an object of the present invention to provide a method for manufacturing a color filter that simplifies the process.

[0009]

According to the method of manufacturing a color filter of the present invention, a colored resist of the remaining one color is applied to a substrate on which a filter of at least one color is formed, and the photosensitive wavelength range of the colored resist is applied. Among these, the back exposure is performed by ultraviolet rays through an ultraviolet ray cut filter that blocks light in the ultraviolet side transmission wavelength range of the filter.

[0010]

According to the above method, the ultraviolet cut filter blocks the light in the ultraviolet transmission wavelength range of the previously prepared filter out of the photosensitive wavelength range of the remaining colored resist of one color. There is no possibility that a part of another unit color filter may be formed on the created unit color filter so as to overlap. As a result, the margin when forming the unit color filter of the remaining one color becomes large, so by adjusting the exposure amount during the back exposure, the thickness of the unit color filter of the remaining one color is the unit created earlier. It can have the same thickness as the color filter. Therefore, the surface of the color filter can be smoothed, the viewing angle characteristics of the STN liquid crystal display device can be greatly improved, and defects such as an overedge during the patterning of the ITO electrode on the surface can be prevented. obtain. Further, since the light-shielding film is formed at the same time when the unit color filter for the remaining one color is formed, the manufacturing process is simplified.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in FIG. 1 and FIG. In the present embodiment, first, for example, R (red) and G (green) unit color filters 3a and 3b are provided on the transparent substrate 1 such as a glass substrate by dyeing, pigment dispersion, electrodeposition or the like corresponding to each pixel. Formed and then the remaining color B
A (blue) colored resist 5 is applied (FIG. 5A).
Next, back exposure is performed with ultraviolet rays through the ultraviolet ray cut filter 6 (FIG. 5B). And the unit color filter 3
By leaving a portion which is not blocked by a and 3b and exposed to ultraviolet rays, a blue color B is provided between the unit color filters 3a and 3b.
The unit color filter 3c is formed together with the light shielding film (FIG. 5C).

In this case, as shown in the transmission characteristic diagram of FIG. 2, the transmission characteristic of the ultraviolet cut filter 6 is such that light in the ultraviolet side transmission wavelength range of the red R filter is included in the photosensitive wavelength range of the blue B colored resist 5. Is blocked, and light in the transmission wavelength range of the blue B filter is transmitted. That is, for example, 3
The light having a wavelength of 80 nm or less is cut off.

According to the method of the present invention, the ultraviolet cut filter 6 shields the remaining one color, that is, the light in the ultraviolet side transmission wavelength range of the red R filter, which is previously prepared, of the photosensitive wavelength range of the colored resist 5 of blue B. Therefore, there is no possibility that a part of the blue color B unit color filter 3c is overlapped on the red color R unit color filter 3a. As a result, the margin for forming the blue B unit color filter becomes large. Therefore, the thickness of the blue B unit color filter 3c can be adjusted to adjust the exposure amount at the time of the back exposure. The unit color filters 3a and 3b for R and green G can have the same thickness. Therefore, the surface of the color filter can be smoothed and S
It is possible to significantly improve the viewing angle characteristics of the TN liquid crystal display device and prevent defects such as overedges when the ITO electrode is patterned on the surface. Further, since the light-shielding film is formed at the same time when the unit color filter 3c for blue B is formed, the manufacturing process is simplified.

[0014]

As described above, according to the method of the present invention, there is no possibility that a part of another unit color filter is formed on the previously prepared unit color filter and the surface of the color filter is formed. Can be smoothed, and the viewing angle characteristics of the STN liquid crystal display device can be significantly improved,
There is an important practical advantage that defects such as an overedge during patterning of the ITO electrode on the surface can be prevented and the manufacturing process can be simplified.

[Brief description of drawings]

FIG. 1 is a diagram showing steps of an embodiment of a method for producing a color filter according to the present invention.

FIG. 2 is a transmission characteristic diagram of the ultraviolet cut filter used in the above-mentioned embodiment.

FIG. 3 is a diagram showing steps of an example of a conventional color filter producing method.

FIG. 4 is a diagram showing a process of another example of the conventional method for producing a color filter.

FIG. 5 is a diagram showing a process of still another example of the conventional method for producing a color filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Light-shielding film 3a R unit color filter 3b G unit color filter 3c B unit color filter 5 Colored resist 6 UV cut filter

Claims (1)

[Claims] 1. A colored resist of the remaining one color is applied to a substrate on which a filter of at least one color is partially formed,
A method of manufacturing a color filter, wherein back exposure is performed by ultraviolet rays through an ultraviolet ray cut filter that blocks light in the ultraviolet ray transmission wavelength range of the filter in the photosensitive wavelength range of the colored resist.