JP3142900B2 - Manufacturing method of color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to is a method of manufacturing a color filter, red detail further can enable color display by combining a monochrome liquid crystal display device of the blue, green 3 The present invention relates to a method for manufacturing a color filter for a liquid crystal display device comprising a dot matrix of a primary color or a color filter portion having a predetermined pattern shape and a black light-shielding layer filling between the three primary colors.

[0002]

2. Description of the Related Art Liquid crystal display elements have been the mainstream of conventional display devices because of their features such as thinness, lightness and low power consumption.
In recent years, remarkable developments have been shown as an alternative to an RT (cathode ray tube), but a color filter is indispensable to colorize this display element and obtain a display performance closer to a CRT. Various materials and methods have been proposed.

A typical example thereof is a dyed color filter obtained by dyeing a thin film of a natural polymer such as gelatin with a dye, and has been used in a small liquid crystal type color television and the like. Although this dyed color filter was excellent in terms of transmittance and chromaticity, several drawbacks have been pointed out as the size of liquid crystal display elements has been increasing in recent years.

That is, there is a lack of uniformity of chromaticity over a large area, a high cost due to the complexity of the process, and a lack of heat resistance and weather resistance due to the use of a dye.

In order to make up for these disadvantages, in recent years, a so-called pigment dispersion method in which a pigment is used as a pigment and the pigment is dispersed in a photosensitive resin in advance has been receiving attention.
The production of a color filter by a pigment dispersion method is generally performed by the following steps.

First, a light-shielding layer called a black matrix is formed on a transparent substrate such as glass or plastic. The light-shielding layer is In its contact to the liquid crystal element of the TFT type is provided in order to hold or preventing deterioration in the contrast of the characteristics of the transistors are formed by high chromium thin film to the normal light-shielding.

[0007] Contact simple matrix driving represented by a liquid crystal element of the STN mode information, originally or lower than the contrast TFT type of these devices, due to the pursuit of low cost, black matrix is omitted Usually, they are formed by superposition of three primary colors, and high light-shielding properties are not always provided.

Next, a colored resist containing a pigment and a photosensitive resin is applied, and a PVA (polyvinyl alcohol) layer is applied as an oxygen barrier film on the colored resist layer. Then, an unexposed portion is removed by development to form a color pattern. This operation is repeated twice with another color to form a color filter of three primary colors.

[0009]

One of the problems that arises when a color liquid crystal element is produced using the color filter thus formed is the presence of pinholes or foreign matter in the color filter.

[0010] Above all, pinholes of the color filter cause light leakage of the liquid crystal element and cause significant deterioration of the display appearance. Therefore, eliminating the pinhole is an important point in the production of the color filter. The object of the present invention is to provide a thick film with good productivity.
But it forms a well-cured good black matrix
And shield the pinholes in the color filter from light.
To improve the display quality.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and includes a step of forming a color filter having a predetermined pattern on a transparent substrate, and a step of forming a photo-curing layer on substantially the entire surface of the color filter. Forming a liquid layer for forming a light-shielding film by applying a liquid for forming a light-shielding film, and a step of exposing the liquid layer for forming a light-shielding film. In the step of exposing the liquid layer for forming, the step of patterning and exposing the liquid layer for forming a light-shielding film from above and the step of exposing substantially the entire surface of the substrate from the side opposite to the transparent substrate are performed simultaneously or sequentially.
Black matrix
Turn is slightly wider than the gap determined by the color filter
A method for producing a color filter is provided, which is a step of forming the color filter to be wider . Further, a step of forming a color filter having a predetermined pattern on the transparent substrate and forming a light-shielding film forming liquid layer by applying a photocurable light-shielding film forming liquid over substantially the entire surface of the color filter. In the method for producing a color filter, comprising the steps of: exposing the light-shielding film-forming liquid layer, exposing the light-shielding film-forming liquid layer; And a step of exposing substantially the entire surface of the substrate from the opposite side of the transparent substrate, simultaneously or sequentially, so that the width is slightly wider than the gap determined by the color filter. and forming a black matrix pattern, provides a method for producing a color filter according to claim <br/> step is a step of changing the pin hole in the color filter black defect I do. That is, high quality color display is enabled by removing pinholes in the color filter.

Another object of the present invention is to provide red, blue,
Green mutual positional accuracy and shape of each color filter of precisely defined, thereby is obtained by enabling Kusuru that such a reduction in light leakage and the aperture ratio of each pixel of the liquid crystal display device.

[0013] In the following, it will be described in detail the content of the present invention in further.

The production of the color filter according to the present invention is performed as follows. First, the colored resist liquid on a glass substrate was coated, applying the oxygen barrier film such as PVA film on this further. Next, exposure is performed through a photomask,
The colored resist is patterned into a predetermined shape.

After forming the first color pattern in this way, the same operation is repeated to form the second and third color filter patterns. The color filter pattern formed here has a certain degree of shape and positional error due to the performance of the apparatus used at the time of exposure or development conditions in any of the stripe, delta, and mosaic cases. This error may also be caused by a difference in the type of material used, and it is difficult to form all three color patterns in a predetermined shape and position.

Next, a liquid for forming a light-shielding film such as a resist colored black is applied on the color filter. Then, exposure is performed from the application surface side through a patterned photomask, and at the same time, exposure is performed almost entirely from the opposite glass surface, without passing through the photomask. Thereafter, by performing development, a predetermined black matrix pattern is formed, and a color filter substrate that enables high-contrast display in which the gap between display electrodes of the liquid crystal display element is covered with the black matrix is formed. Here, the exposure through the photomask from the application surface is performed so that a predetermined black matrix pattern is formed irrespective of the shape and position accuracy of the color filter.
It is formed slightly wider than the gap determined by the color filter.

[0017] Simultaneously, exposure over substantially the entire surface from the glass substrate side is selectively performed on a gap portion determined by the color filter and a pinhole portion formed in the color filter, and overlaps the color filter. Not enough light reaches the part of the black resist. Thus, the development of subsequent, to together the black matrix pattern is formed into a predetermined shape, black layer is formed in the pinhole portions that occur in the color filter, a pinhole portion would be repaired. In this manner, of the defects in the color filter, those caused by pinholes are removed, and a good appearance can be given to the color liquid crystal display device. At the same time, the three primary colors are accurately arranged in the portion surrounded by the black matrix.

The light-shielding film-forming liquid is a material that is cured by light such as ultraviolet rays, have good anything as long as it has a light blocking property after curing. A photo resist mixed with a black pigment such as carbon or a photo-curable resin is preferably used.

The method of patterned exposure is preferably the easiest to perform through a photomask, such as by light beam scanning, but it may also in other ways.

When exposing from the opposite side of the transparent substrate, exposure is performed on almost the entire surface of the substrate. More specifically, it not good is carried out for the portion corresponding to the effective display area in the case of incorporating a color filter in the liquid crystal display element.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a sectional view showing one example of the process of the present invention.

Example 1 A glass substrate 1 having one surface polished and flattened was washed and dried, and a color resist in which a red pigment was dispersed was applied and dried, and then a PVA film as an oxygen barrier film was applied and dried. Subsequently, exposure and development were performed to form a stripe pattern by photolithography. The film thickness of the red pattern R obtained here was approximately 2.mu. m. Green pattern G and then at a similar manner, about each blue pattern B 2.mu. m
And a pattern of three primary colors was obtained. These patterns about 5 ~ 20 [mu] m than the display pattern of the color liquid crystal display device obtained by using the color filter substrate
The dimensions were made larger. Thus the diameter at a certain ratio to the color filter created contained a pinhole 6 of about 10 ~ 100μ m (Figure 1 (a)).

Next, a black resist 2 is applied on the color filter thus obtained, dried, and a PVA film 3 is further applied and dried (FIG. 1B).

[0024] The first through the photomask 4 having a pattern already aligned pattern so as to completely cover the three primary mutual gap portion being formed from the coating surface side during exposure of the substrate Then, a second exposure was performed on the entire surface of the substrate from the back side of the glass substrate (FIG. 1C). The substrate is exposed and developed to a film thickness of 1.3.
give mu m, the black matrix 5 of the line width of about 30.mu. m (FIG. 1 (d)). Although the black resist is patterned in a matrix by the first exposure, a portion corresponding to the pinhole is not effectively irradiated with ultraviolet light because it is blocked by a photomask. Pinhole 及 beauty red second ultraviolet light from the back surface of the substrate by the exposure is missing part of the irradiated color filter followed,
Ultraviolet light is applied to the gap between the blue and green color filters, and these portions are cured.

As described above, the black resist remains in the pinhole portion in the color filter, and the so-called "white defect" is changed to "black defect", and the defect having a large influence on the display quality of the liquid crystal display element is changed to a defect having a small influence. The conversion was made. Also. Since the curing of the portion in contact with the glass surface of the second black resist by exposure proceeds, black resist of the color filter over between <br/> gap portion is made ultraviolet light irradiation from the upper and lower surfaces, and 1.3Myu m Despite being relatively thick,
A good film could be formed. Thus, a good color filter substrate having a transmittance of the black matrix portion of 1% or less was obtained.

Example 2 For producing a color filter substrate similar to that of Example 1,Hey
The exposure equipment used to expose the black resist
Using a possible device,1And the second2Exposure at the same time
Was. The results are the same as in Example 1, except that the pinhole portion is
Completely restored.

[0027] In Example 3 Example 1 was subjected to exposure through the nitrogen gas between the photomask and the substrate during exposure instead of the PVA film formed on the color resist 及 beauty black resist, P
The same result as that obtained when the VA oxygen barrier film was used was obtained.

[0028]

According to the present invention, a color filter with less noticeable pinholes can be obtained. Also, the mutual positional accuracy and shape of the red, blue, and green color filters are accurately specified to prevent light leakage and decrease in the aperture ratio of each pixel of the liquid crystal display element.
It can be such Kusuru.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Black resist 3 PVA film 4 Photomask 5 Black matrix

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 5/20-5/28

Claims (2)

(57) [Claims] 1. A step of forming a color filter having a predetermined pattern on a transparent substrate, and applying a photocurable light-shielding film forming liquid to substantially the entire surface of the color filter to form a light-shielding film forming liquid layer. Forming a light-shielding film forming liquid layer, and exposing the light-shielding film forming liquid layer to the light-shielding film forming liquid layer. , have at the same time or sequentially rows exposing substantially the entire substrate from the opposite side of the step and the transparent substrate to be exposed by patterning from above, the light-shielding property to be
The black matrix pattern formed by the film is
Is slightly wider than the gap determined by the color filter
A process for producing a color filter. 2. A step of forming a color filter having a predetermined pattern on a transparent substrate, and applying a light-curable light-shielding film forming liquid to substantially the entire surface of the color filter to form a light-shielding film forming liquid layer. Forming a light-shielding film forming liquid layer, and exposing the light-shielding film forming liquid layer to the light-shielding film forming liquid layer. The step of exposing using a photomask patterned from above and the step of exposing almost the entire surface of the substrate from the opposite side of the transparent substrate are performed simultaneously or sequentially, so that the color filter is determined.
To form a somewhat wide black matrix pattern than chance, a method for manufacturing a color filter which is a process of changing the pin hole in the color filter black defect.