JPH06208018A - Production of color filter - Google Patents

Abstract

PURPOSE:To uniformalize the width of a black matrix and to enable the use of a material which does not generate limitation in light shieldability and has low electric resistance as the black matrix. CONSTITUTION:The black matrix 2 is formed on a glass substrate 1 and thereafter, filter parts 5, 6, 7 of respective colors are formed. This formation is so executed that the ends of the filter parts 5, 6, 7 of the respective colors exist on the black matrix 2 and, therefore, the filter parts 5, 6, 7 of the respective colors are registered with relatively good accuracy and eventually the width of the black matrix 2 is uniformalized. The black matrix 2 and the filter parts 5, 6, 7 of the respective colors are formed with ITO electrodes 3 therebetween and the black matrix 2 is not directly superposed on the filter parts 5, 6, 7 of the respective colors and, therefore, the degradation in the film quality does not arise any more even if metals and resins having the low electric resistance are used for the black matrix 2.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art As shown in FIG. 3, the above color filter has a set of a red (R) color filter section 5, a green (G) color filter section 6, and a blue (B) color filter section 7. A plurality of sets are formed on the glass substrate, and the black matrix 8 is formed on the portions where the red, green, and blue filter portions 5, 6, and 7 are not formed.

A method shown in FIG. 4 has been proposed as a method for manufacturing a color filter having such a structure {Japanese Patent Laid-Open No. 61-272720 and Nikkei Sangyo Shimbun (1990.10.22).
Liquid crystal color filter made by Nippon Paint Co., Ltd.)}. The method is performed as follows.

First, as shown in FIG. 4A, the ITO electrode 3 and the positive resist 4 are applied in this order on the entire surface of the glass substrate 1.

Next, a part of the positive resist 4 is removed by exposure and development to expose the ITO electrode 3 part where the color filter is to be formed, and the substrate in this state is immersed in an electrodeposition bath to apply a voltage. Then, an electrodeposited color filter is deposited on the exposed portion of the ITO electrode 3, followed by washing with water and baking to obtain a cured red filter portion 5 (see FIG. 4 (b)). This process is repeated in the same manner, and as shown in FIGS. 4C and 4D, the green filter unit 6,
The blue filter portion 7 is obtained.

Finally, as shown in FIG. 4 (e), the remaining portion of the positive resist 4 is peeled off, and the substrate in this state is dipped in a black electrodeposition solution for electrodeposition, and the filter portion 5 for each color is formed. ,
A black matrix 8 is formed between 6 and 7.

Furthermore, an improved method of the above method has been proposed (EID90-120: IBM Japan). In this improvement method, an ITO electrode is formed on the entire surface of a glass substrate by sputtering or vapor deposition, and a black negative photosensitive resin mixed with an organic pigment is used to form a black matrix on the ITO electrode. Next, a positive resist is applied on the black matrix, and subsequently, using a photomask having a light transmission area wider than that of the black matrix, exposure and development are performed to expose the ITO electrode portion where the filter portion is to be formed. After that, the red, green, and blue filter portions are formed by electrodeposition in the same manner as the above-mentioned method.

[0008]

By the way, in the case of the method described with reference to FIG. 4, since the black matrix 8 is formed after the filter portions 5, 6, 7 of each color are formed on the ITO electrode, each color is formed. There is a problem that the width of the black matrix 8 varies as shown in FIG. 3 due to the shift of the formation positions of the filter parts 5, 6, and 7.

On the other hand, in the case of the improved method, although the filter portion is formed after the black matrix is formed, if a material having a low electric resistance is used for the black matrix, the black matrix is formed in the subsequent formation of the filter portion by electrodeposition. Since the filter part is formed on the upper part and the film quality on the black matrix deteriorates, it is necessary to use an organic material having a high electric resistance in order to prevent this, and as a result, the light shielding property is limited. There's a problem.

The present invention has been made to solve the above-mentioned problems of the prior art, and a material having a uniform width of the black matrix and having a low light-shielding property and a low electric resistance is used as the black matrix. It is an object to provide a method of manufacturing a color filter that can be used.

[0011]

According to the method of manufacturing a color filter of the present invention, a red filter portion, a green filter portion and a blue filter portion are formed in a predetermined pattern on a glass substrate, and the filter portion is not formed. In a method of manufacturing a color filter in which a black matrix is formed in a portion, a step of forming a black matrix made of a resin or a metal in which a pigment having a low electric resistance and a high light blocking rate is dispersed in a predetermined pattern on a glass substrate. And a step of forming a transparent electrode on the entire surface of the black matrix, a step of forming a resist film on the transparent electrode, a part of the resist film is removed, and the exposed transparent electrode part is formed. The step of forming the red color filter portion in a state where the end of the red color filter portion is located on the black matrix, and a part of the resist film is removed and exposed. A step of forming a green filter part on the bright electrode part so that its end is located on the black matrix, and removing a part of the resist film to form a blue part on the exposed transparent electrode part. Forming the filter portion such that its end is located above the black matrix, whereby the above object is achieved.

[0012]

In the present invention, the black matrix is formed on the glass substrate, and then the filter portion for each color is formed. At the time of this formation, since the filter portion of each color is performed so that its end is located on the black matrix, the alignment of the filter portion of each color is relatively accurately performed.
As a result, the width of the black matrix becomes uniform.
Further, since the black matrix and the filter part of each color are formed with the transparent electrode in between and the black matrix and the filter part of each color do not directly overlap with each other, a metal or resin having a low electric resistance is added to the black matrix. Even if you use, the deterioration of the film quality will disappear.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a process chart for explaining the method of manufacturing the color filter of this embodiment. First, FIG. 1 (a)
As shown in FIG. 2, a chromium film for a black matrix is formed on a glass substrate 1 made of Corning 7059 by sputtering, a photoresist (OFPR5000) is applied on the chromium film, and then exposure, development and baking are performed. After that, dry etching is performed with SF6 gas to form a black matrix pattern 2 made of chromium on the glass substrate 1.

Next, as shown in FIG. 1B, an ITO electrode 3 is formed on the entire surface of the glass substrate 1 on which the black matrix pattern 2 is formed by sputtering, and then IT
A positive resist 4 is applied on the entire surface of the O electrode 3.

Next, as shown in FIG. 1C, a part of the positive resist 4 is removed, and a red filter part 5 is formed on the removed part. To describe this in detail, the positive resist 4 is aligned so that the end of the part where the part of the positive resist 4 has been removed fits within the width of the black matrix 2 thereunder, that is, the black matrix 2 is above. After that, exposure and development are performed to expose the portion of the ITO electrode 3 where the red filter portion 5 is to be formed. The glass substrate 1 in such a state is immersed in an electrodeposition liquid bath described below, and a voltage of 50 V is applied to form the red filter portion 5. The above electrodeposition bath is
For example, a pigment having an average particle diameter of 0.17 μm, which is obtained by adding 30% of a yellow pigment to a red pigment, is added to an acrylic resin by
Was used at a pH of 9 or less.

Next, as shown in FIG. 1D, a part of the positive type resist 4 is further removed, and the removed part is
The green filter portion 6 is formed. This will be described in detail. The positive resist 4 is partly removed so that the end of the positive resist 4 is located above the underlying black matrix 2, and then exposure and development are performed to obtain a green filter portion. The portion of the ITO electrode 3 where the 6 is to be formed is exposed. The glass substrate 1 in this state is dipped in an electrodeposition liquid bath described below, and a voltage of 55 V is applied to form a green filter portion 6. As the electrodeposition liquid bath in this case, for example, a pigment having an average particle diameter of 0.12 μm obtained by adding 40% of a yellow pigment to a green pigment is dispersed in an acrylic resin at a ratio of ⅕ to What was set to 9 or less was used.

Next, as shown in FIG. 1 (e), the entire surface of the glass substrate 1 is irradiated with ultraviolet light to develop and remove the positive resist 4 to form red and green filter portions 5 and 6. The upper part of the ITO electrode 3 not exposed is exposed. The glass substrate 1 in such a state is immersed in an electrodeposition liquid bath described below, and 50
A voltage of V is applied to form the blue filter portion 7. As the electrodeposition liquid bath in this case, for example, a pigment having an average particle diameter of 0.1 μm obtained by adding 30% of a yellow pigment to a blue pigment,
The one having a PH of 9 or less was used which was dispersed in the acrylic resin at a ratio of 1/5.

Therefore, in the case of this embodiment, the black matrix 2 is followed by the filter portions 5, 6, 7 for each color.
And forming the filter parts 5, 6, 7 for each color, the positioning is performed so that the ends of the filter parts 5, 6, 7 for each color are located on the black matrix 2. That is, the shape of the filter portion for each color is automatically determined by the pattern of the black matrix previously formed. Therefore, as shown in FIG. 2 (plan view), the width of the black matrix 2 is substantially constant,
It is possible to manufacture a color filter in which the filter parts 5, 6, and 7 of each color have no shape irregularity. Further, since the black matrix 2 and the filter parts 5, 6, 7 of each color are formed with the ITO electrode 3 interposed therebetween, the black matrix 2 and the filter parts 5, 6, 7 of each color do not directly overlap each other. Therefore, even if chrome having a low electric resistance is used for the black matrix 2, the film quality is not deteriorated.

Although chromium is used for the black matrix 2 in the above embodiment, the present invention is not limited to this, and other metals or a resin in which a pigment having a low electric resistance and a high light shielding rate is dispersed is used. can do.

An example of a manufacturing method in the case of using a resin in which a pigment having a low electric resistance and a high light blocking rate is dispersed will be described below. On the glass substrate 1 made of Corning 7059, a negative photosensitive resin (resistance value 10 ⁹ Ωcm) in which carbon black is dispersed is applied, and then exposed and developed to form the black matrix 2.
The black matrix 2 has a film thickness of, for example, 1.
It is preferable that the thickness is 5 μm and the average transmittance of visible light is 1% or less. After forming the black matrix 2,
Similarly as before, the ITO electrode 3 was vapor-deposited on the entire surface by sputtering, and the positive photoresist 4 was applied thereon, and sequentially.
The ITO electrode 3 in the portion where the filter portion is to be formed is exposed and the filter portions 5, 6, 7 of each color are formed by electrodeposition.

In this example using a resin, carbon black is used for the pigment and a negative photosensitive resin is used for the resin, but other materials can be used for both the pigment and the resin.

In the above embodiment, the filter portion for each color is red,
Although formed in the order of green and blue, the present invention is not limited to this,
The order is arbitrary. For example, the order of formation may be red, blue, green, or blue, green, red.

[0024]

As described above in detail, in the case of the present invention, since the filter portion of each color and the black matrix are not in contact with each other, the material of the black matrix can be selectively used regardless of the electrical resistivity. It becomes possible, and there is no problem even if metal or resin with low resistance is used. In addition, since the filter part of each color is formed so that its end is located above the black matrix, that is, the shape of the filter part of each color is automatically determined by the pattern of the black matrix formed earlier. Since the filter part of each color is formed, it is possible to realize a color filter having a uniform black matrix without unevenness in shape.

[Brief description of drawings]

FIG. 1 is a process drawing for explaining a method for manufacturing a color filter of the present invention.

FIG. 2 is a plan view partially showing a color filter manufactured by the method of the present invention.

FIG. 3 is a plan view partially showing a color filter manufactured by a conventional method.

FIG. 4 is a process drawing for explaining a conventional color filter manufacturing method.

[Explanation of symbols]

 1 Glass Substrate 2 Black Matrix 3 ITO Electrode 4 Positive Resist 5 Red Filter 6 Green Filter 7 Blue Filter

Claims (1)

[Claims] 1. A method of manufacturing a color filter in which a red filter portion, a green filter portion and a blue filter portion are formed in a predetermined pattern on a glass substrate, and a black matrix is formed in a portion where the filter portion is not formed. In the above step, a step of forming a black matrix made of a resin or a metal in which a pigment having a low electric resistance and a high light shielding rate is dispersed in a predetermined pattern on a glass substrate, and forming a transparent electrode on the entire surface of the black matrix. And a step of forming a resist film on the transparent electrode, a part of the resist film is removed, a red filter part is provided on the exposed transparent electrode part, and an end thereof is on the black matrix. And a part of the resist film is removed, and a green filter part is formed on the exposed transparent electrode part, and its end is Forming in a state of being located on the rack matrix, and removing a part of the resist film to form a blue filter part on the exposed transparent electrode part, and an end of which is located on the black matrix. And a method of manufacturing a color filter, the method including: