JPH10300916A - Manufacturing method of color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color filter manufacturing method which can form a colored pixel with few defects by a method which is extremely simplified as compared with the prior art, and does not require waste liquid treatment of a developing solution. To do. A method of manufacturing a color filter in which pixels of at least two colors are formed on a transparent substrate includes:
Forming a film to be dyed on the transparent substrate, and then irradiating the laser light to a portion other than the region serving as the pixel of the first color to evaporate and remove the film to be dyed in the irradiated portion; (2) Step ( (1) a step of coloring the film to be dyed in a region to be a pixel of the first color formed by 1) with a coloring liquid containing a dye of the first color to form a pixel of the first color; A film to be dyed is formed on the entire surface of the substrate including the pixels, and then a laser beam is applied to a portion other than the region serving as the pixel of the second color,
(4) coloring the film to be dyed in the region to be the pixel of the second color formed in step (3) with a coloring liquid containing a dye of the second color; And a step of forming a second color pixel.

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 to be mounted on a color liquid crystal display, a color facsimile, a color video camera, etc., and more particularly, to a method of forming a pattern of colored pixels on a transparent substrate. The present invention relates to a method for manufacturing a color filter.

[0002]

2. Description of the Related Art A color liquid crystal display is provided with a color filter having pixels of two or more colors, usually three colors, formed on a transparent substrate. Generally, as three colors,
The three primary colors red, blue and green are used. If desired, pixels of the fourth color or more having different hues may be formed. Further, a black matrix may be formed. These pixels are formed in a pattern on a transparent substrate by various methods.

Conventionally, as a method of manufacturing a color filter, (A) a dyeable resin film having photosensitivity is formed on a transparent substrate, and the dyeable resin film is patterned by photolithography. A method of forming a colored pixel by dyeing a relief (relief dyeing method), (B) forming a dyeable layer made of a dyeable polymer material on a transparent substrate, and forming a dye-resistant resist film thereon Is formed in a pattern and used as a mask, and the exposed portion of the layer to be dyed is dyed in a desired color (mask dyeing method). (C) A pigment is dispersed in a photosensitive resin on a transparent substrate. A method (a pigment dispersion method) of forming a coating layer of a coloring composition and patterning the layer by photolithography is known. Among these methods, the pigment dispersion method using a pigment as the colorant (C) generally has a disadvantage that the contrast of the colored pixels is lower than the method using a dye. Also, (A)
In the method of performing patterning by photolithography of (C) to (C), a wet etching method is adopted.
In the development process, there are disadvantages such as undissolved matter and dust from the developer being mixed into the pixels, causing pixel defects, and further requiring waste liquid treatment of the developer.

Conventionally, unlike these methods, as a method that does not use a wet etching method for patterning pixels,
(D) A method has been proposed in which a photoresist pattern is formed on a colored hydrophilic polymer layer containing a dye and used as a mask to perform patterning by a dry etching method such as plasma etching (Japanese Patent Laid-Open No. 57-17230).
4). In this method, by using a colored hydrophilic polymer as a colored polymer layer and dry-etching,
It is stated that physical properties such as swelling, stains, adhesion and the like, which are problems in wet etching, can be prevented, and there is little side etching and the like, and pattern accuracy can be improved. As a method that does not require a developing step, (E)
A heat-sensitive layer is formed on a color element receiving layer coated on a support, and the color element receiving layer is partially exposed by irradiating high-density energy radiation according to a pattern, and then the part is dyed. There has been proposed a method of forming a pattern by using the method (Japanese Patent Publication No. 1-57762).

However, in the method (D), a mask forming step is required, and since this step is performed by photolithography, a photoresist is required in addition to a material for forming a pixel. A process is required, and therefore wastewater treatment is also required.
In the method (E), the problem caused by the developing step is solved because there is no developing step. However, the removal of the photosensitive layer is performed by converting light energy into heat, and the heat is used. In addition to the problem that the edge of the pattern becomes dull, the surface of the color element receiving layer at the exposed portion is also affected by the heat, causing a problem that the film thickness changes and the smoothness deteriorates. Further, in the conventional relief dyeing method, it is necessary to use a photosensitive resin having a resolution required for pattern formation as a dyeable resin.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing a color filter capable of forming a colored pixel having few defects by a method which is extremely simplified as compared with the prior art. . Another object of the present invention is to provide a method for manufacturing a color filter which does not require waste liquid treatment of a developer unlike the conventional method using a photosensitive resin.

The inventors of the present invention have conducted intensive studies to overcome the problems of the prior art. As a result, a film to be dyed is formed on a transparent substrate, and unnecessary portions (pixels of the first color) are formed by a laser irradiation method. Of the first region) is removed by evaporation.
A film to be dyed in a region to be a pixel of a color is formed in a pattern, and then the film to be dyed in a pattern is dyed with a coloring liquid containing a dye to form a pixel of a first color. By repeating the above, it was found that a color filter having at least two color pixels was obtained.

According to this method, it is not necessary to use an expensive photosensitive resin as a material for forming a film to be dyed, and since there is no development step, a colored pixel having no pixel defect can be obtained. It is possible to obtain a remarkable function and effect that a color filter having excellent flatness can be obtained, and a color filter having excellent contrast can be obtained because a dye is used as a colorant. The present invention has been completed based on these findings.

[0009]

According to the present invention, there is provided a method for manufacturing a color filter in which at least two color pixels are formed on a transparent substrate, (1) forming a film to be dyed on a transparent substrate, Irradiating the laser light to a portion other than the region to be the first color pixel to evaporate and remove the film to be dyed in the irradiated portion; (2) the first color pixel formed in the step (1); Forming a pixel of the first color by coloring the film to be dyed in a region to be formed with a coloring liquid containing a dye of the first color; (3) coating the film to be dyed on the entire surface of the substrate including the pixel of the first color Forming, and then irradiating the laser light to a portion other than the region serving as the pixel of the second color to evaporate and remove the film to be dyed in the irradiated portion. (4) The second step formed in the step (3) A film to be dyed in a region to be a pixel of a color is applied with a coloring liquid containing a dye of a second color. Then, the step of forming pixels of the second color, and (5) if necessary, the same steps as steps (3) and (4) are repeated to form pixels of the required number of colors after the third color And a method of manufacturing a color filter having at least two color pixels formed therein.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIG. First, as shown in FIG.
A film to be dyed 2 is provided on a transparent substrate 1. As a transparent substrate, glass, a transparent thin plate made of synthetic resin, a sheet,
Films and the like. A substrate on which a black matrix is formed in advance can also be used as the substrate. The black matrix fills or covers the gaps between the colored pixels with a light-shielding substance, and has a role of improving the contrast of the color filter. As the material of the black matrix, for example,
Chromium, chromium oxide thin film, carbon black, graphite,
There is a resin composition mixed with a light-shielding substance. The black matrix may be formed by the same method as forming the colored pixels.

The film to be dyed is usually formed using a resin having a dyeing property. Such a resin is not particularly limited as long as it has a dyeing property, and examples thereof include natural polymer materials such as gelatin, glue, and casein, and synthetic polymer materials such as polyvinyl alcohol, polyvinylpyrrolidone, and an acrylic resin. Can be The film to be dyed is generally formed by applying a solution of a resin having dyeability on a transparent substrate by a coating method such as a spin coater, a roll coater, or a bar coater, and drying. The thickness of the film to be dyed can be appropriately determined depending on the application, but is usually about 0.5 to 3 μm.

Next, as shown in FIGS. 1 (a) and 1 (b), a portion other than the region 4 serving as the pixel of the first color is irradiated with the laser beam 3 to evaporate the film to be dyed at the irradiated portion. The pattern 4 is formed. The laser light used here is preferably a laser light having a wavelength in the ultraviolet region because of its high shape accuracy, and an excimer laser is particularly preferable. Examples of excimer lasers include ArF, K
There are rF and XeCl lasers. CO ₂ , Y
Laser light having a wavelength in the infrared region such as an AG laser can also be used. However, in this case, it is preferable that laser light of a short wavelength is produced using a nonlinear optical element, and the laser light of this wavelength is irradiated.

The laser beam is irradiated using a mask, or is irradiated without using a mask by adjusting the line width of the laser beam. At this time, the laser light is selectively irradiated to a portion other than the region to be the pixel of the first color, and the film to be dyed at the irradiated portion is removed by evaporation, and the region to be the pixel of the first color is formed in a pattern. Form. The energy density of the laser light is usually about 0.2 to 3 J / cm ² . In order to control the output of the laser light, it is preferable that the laser light is pulse light. This is because processing control in the depth direction of the film to be dyed is facilitated by the number of shots of the pulsed light.

A pixel to be formed (or a region to be a pixel)
Is appropriately selected according to the purpose, but is usually approximately 100 × 300 μm, and the pixel interval is approximately 30 μm. There are two methods for irradiating the laser light, one is a method of surface exposure through a photomask, and the other is a method of narrowing down the laser light and scanning. Usually, it is preferable that the size of the spot of the laser beam is such that one of the length and width of the spot is at least 30 μm or less. As a method of scanning with laser light, there is a method of moving the substrate itself on an XY stage or a method of scanning with laser light using an optical system. This method does not require a photomask, and is particularly advantageous for fine processing.

As shown in FIGS. 1 (b) and 1 (c), the patterned film 4 to be dyed is colored with a first color liquid containing a dye (for example, red; R). Fix it. Thereby, the pixel 4 of the first color (for example, red)
R is formed. The dye to be used is not particularly limited, but in terms of group, acid dyes and reactive dyes are particularly preferable. Chemical structures include, for example, azo dyes, phthalocyanine dyes, anthraquinone dyes, triphenylmethane dyes, and indigoid dyes. The dye is fixed as required. The fixing process of the dye
The whole substrate is, for example, 50 to 90 ° C. of a tannic acid aqueous solution.
In a bath for 1 to 60 minutes, and then add 50
For example, there is a treatment by placing the solution in a bath at ~ 90 ° C for about 1 to 30 minutes.

Next, as shown in FIG. 1D, in a second color pattern forming step, first, a film to be dyed 5 is formed on the entire surface of the substrate on which the first color pixels are formed. The dyed film 5 includes a dyed film 5 a formed directly on the substrate 1,
There is a film to be dyed 5b formed on the colored pixel 4R. Next, the laser light is applied to a portion other than the region to be the pixel of the second color, and the film to be dyed in the irradiated portion is removed by evaporation.
By this step, as shown in FIG. 1E, the film 6 to be dyed in a region to be a pixel of the second color is formed in a pattern.
When irradiating the laser light, the output (including the number of shots) of the laser light is controlled, and only the dyed film 5b is evaporated on the dyed film 5b formed on the colored pixel 4R, so that the first color Colored pixels 4R remain. FIG.
As shown in (e) and (f), the patterned dyed film 6 is colored with a coloring liquid of a second color containing a dye (for example, green; G), and is subjected to a fixing treatment as necessary. As a result, the second color (for example, green) pixel 6G is formed.

In order to form pixels of three colors or more, the same operations as steps (d) to (f) of FIG. 1 are repeated. That is,
As shown in FIG. 1G, first, the colored pixels 4R and 6G
Is formed on the entire surface of the substrate including The dyed film 7 includes a dyed film 7a formed directly on the substrate 1 and a dyed film 7b formed on the colored pixel 4R or 6G. Next, the laser light is applied to a portion other than the region serving as the pixel of the third color, and the film to be dyed in the irradiated portion is removed by evaporation. By this step, as shown in FIG.
The film 8 to be dyed in a region to be a pixel of a color is formed in a pattern.

When irradiating the laser beam, the output (including the number of shots) of the laser beam is controlled to evaporate only the film 7b formed on the colored pixels 4R and 6G. Thus, the first color pixel 4R and the second color pixel 6G remain. FIG. 1 (h)
As shown in (i) and (i), the patterned film 8 to be dyed is a third color liquid containing a dye (for example, blue;
It is colored in B) and, if necessary, fixed. Thereby, the pixel 8B of the third color (for example, blue) is formed.

Normally, by forming the three color pixels on a transparent substrate, a color filter is completed as shown in FIG. 1 (i). If necessary, the fourth and subsequent colored pixels can be formed in a similar manner. Further, a protective film may be formed on the colored pixels. Examples of the material of the protective film include an epoxy resin, a urethane resin, and a polyimide resin.

(Function) In the present invention, the resin (film to be dyed) evaporates by photoreaction by laser light irradiation and patterning is performed, so that edge dulling due to heat does not occur. Furthermore, since a mask resist is not used, it can be manufactured with an inexpensive material, there is no erosion of a dyed film or elution of a dye due to peeling of the mask resist, there is no contamination of impurities from a developer, and pixel defects are reduced. It becomes possible. Also,
Since the development step is not required, the step can be simplified, and the waste liquid treatment of the developer is not required. Swelling, spotting, adhesion, side etching, etc., which are problems in wet etching, do not become a problem, and the pattern accuracy is good.

[0021]

EXAMPLES Hereinafter, preferred embodiments of the present invention will be described more specifically with reference to examples.

Example 1 As shown in FIG. 1, a solution containing 10 g of gelatin, 0.1 g of diazonium salt, and 100 g of water (hereinafter referred to as a resin solution) was applied to an alkali-free glass substrate 1 by a spin coater. Then, after pre-baking at 60 ° C., baking was performed at 100 ° C. to form a film to be dyed 2. Next, a KrF excimer laser (MPB, PS
X-100) is irradiated through a metal mask to an area other than the area where the pixels of the first color are to be formed (FIG. 1A), and the irradiated portion is removed by evaporating. A pattern 4 was formed [FIG. 1 (b)]. The azo dye PC-Red 136P [Nippon Kayaku Co., Ltd.] 1
g, 2 g of glacial acetic acid, and 100 g of water.
After immersion at 0 ° C. for 10 minutes, it was washed with water and stained [FIG.
(C)]. This was added to a 0.3% by weight aqueous solution of tannic acid for 7 days.
After immersion at 0 ° C. for 5 minutes, washing with water, immersion in a 0.09% by weight aqueous tartar solution at 70 ° C. for 1 minute, and fixing by heating at 130 ° C. for 3 minutes, a red pixel 4R [FIG. (C)]
Was formed. The same resin solution is applied on the entire surface of the substrate on which the first color pixels 4R are formed by a spin coater,
After pre-baking at 60 ° C., baking at 100 ° C.
Was formed [FIG. 1 (d)].

Next, a KrF excimer laser (PSX-100, manufactured by MPB) is irradiated through a metal mask to a region other than the region where the second color pixel is formed (FIG. 1D).
The irradiated portion was removed by evaporation, thereby forming a pattern 6 to be a second color pixel [FIG. 1 (e)]. This was immersed in a coloring liquid containing 1 g of a phthalocyanine dye PC-Green FOP [Nippon Kayaku Co., Ltd.], 2 g of glacial acetic acid, and 100 g of water at 70 ° C. for 10 minutes, and then washed with water.
Stained. This was added to a 0.3% by weight aqueous solution of tannic acid for 7 days.
After immersion at 0 ° C. for 5 minutes, washing with water, immersion in a 0.09% by weight aqueous tartar solution at 70 ° C. for 1 minute, and fixing by heating at 130 ° C. for 3 minutes, green pixels (second color) ; 6G)
Was formed [FIG. (F)]. The same resin solution as described above is applied by a spin coater to the entire surface of the substrate on which the first color and second color pixels are formed, and after pre-baking at 60 ° C., 100
The film was baked at ℃ to form a film 7 to be dyed [FIG.

Next, a KrF excimer laser (PSX-100, manufactured by MPB) is irradiated through a metal mask to areas other than the area where the third color pixel is formed (FIG. 1 (g)).
The irradiated portion was removed by evaporation to form a pattern 8 to be a third color pixel [FIG. 1 (h)]. This was immersed in a coloring solution containing 1 g of anthraquinone dye PC-Blue 43P (Nippon Kayaku Co., Ltd.), 2 g of glacial acetic acid, and 100 g of water at 70 ° C. for 10 minutes, washed with water and dyed. This is added to a 0.3% by weight aqueous tannic acid solution at 70%.
Immersion at 70 ° C. for 1 minute, and then fixed by heating at 130 ° C. for 3 minutes to obtain blue pixels [third color; 8B)
Was formed to form a color filter having RGB three-color pixels [FIG. 1 (i)]. The color filter thus obtained had no pixel defects, and when used in a color liquid crystal display, excellent color tone and high contrast could be obtained.

[0025]

According to the method of manufacturing a color filter of the present invention, the film to be dyed is vaporized and removed by photoreaction by irradiation with a laser beam to perform patterning. Therefore, the following remarkable effects can be obtained. it can. (1) There is no dulling of the pattern edge due to heat. (2) In the conventional relief dyeing method, a photosensitive resin having a resolution required for pattern formation was required as a dyeable resin, whereas in the present method, a photosensitive resin having a resolution required for pattern formation was required. Since it is unnecessary, a wide range of materials and inexpensive materials can be used. (3) Since the mask resist is not used, there is no erosion of the dyed film and no elution of the dye due to the removal of the mask resist. (4) Since the developing step is unnecessary, there is no mixing of impurities from the developing solution, and it is possible to reduce pixel defects.
Further, the process can be simplified, and the waste liquid treatment of the developing solution is not required. Furthermore, swelling, spotting, adhesion, side etching, etc., which are problems in wet etching, do not become a problem,
Good pattern accuracy.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing steps (a) to (i) in one embodiment of a method for manufacturing a color filter of the present invention.

[Explanation of symbols]

 1: Transparent substrate 2: Film to be dyed 3: Laser light 4: Patterned film to be dyed for the first color 4R: Red filter (pixels of the first color) 5: Film to be dyed 5a: Film to be dyed on the substrate 5b: Film to be dyed on pixel of first color 6: Patterned film to be dyed of second color 6G: Green filter (pixel of second color) 7: Film to be dyed 7a: Film to be dyed on substrate 7b: First color And the film to be dyed on the pixel of the second color 8: Patterned film to be dyed of the third color 8B: Blue filter (pixel of the third color)

Claims (1)

[Claims] 1. A method of manufacturing a color filter, wherein pixels of at least two colors are formed on a transparent substrate.
Forming a film to be dyed on the transparent substrate, and then irradiating the laser light to a portion other than the region serving as the pixel of the first color to evaporate and remove the film to be dyed in the irradiated portion; (2) Step ( (1) a step of coloring the film to be dyed in a region to be a pixel of the first color formed by 1) with a coloring liquid containing a dye of the first color to form a pixel of the first color; A film to be dyed is formed on the entire surface of the substrate including the pixels, and then a laser beam is applied to a portion other than the region serving as the pixel of the second color,
(4) coloring the film to be dyed in the region to be the pixel of the second color formed in step (3) with a coloring liquid containing a dye of the second color; Then, the step of forming the pixel of the second color, and (5) if necessary, the same steps as steps (3) and (4) are repeated,
Forming a pixel of a required number of colors from the third color onward. A method for manufacturing a color filter in which pixels of at least two colors are formed.