JPH0463389B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for manufacturing a color filter, and its uses include color video cameras and other color filters that recognize light and separate light into different colors. BACKGROUND ART A color filter is used, for example, by arranging color elements in a mosaic or stripe pattern on a light-receiving element surface of a solid-state image sensor for colorizing a color television camera using a solid-state image sensor. The color elements commonly used are blue, red, and green. Photosensitive resins with dyeing properties used in conventional color filters include photosensitive resins made by adding dichromates such as ammonium dichromate or potassium dichromate as photocrosslinking agents to proteins such as gelatin or casein. There is a composition. The general manufacturing method for color filters is to apply dichromate-added gelatin or casein onto a glass plate using a spin coating method, and then irradiate it with ultraviolet rays through a mask to form a latent image of the color element dyed layer. Then, the color element dyed layer is exposed by development. Next, the color element dyed layer is dyed with a dye. In order to form the red, blue, and green color element dyed layers, the above steps are repeated three times while forming an optically transparent intermediate film to prevent mixed dyeing, thereby forming a color filter. Problems to be Solved by the Invention The performances required of the dyeable photosensitive resin used in color filters manufactured through the above steps are (1) good resolution;
(2) It is easy to dye, (3) it has good storage stability, and (4) there is no risk of causing environmental pollution to the photosensitive resin and developer. Photosensitive resins made from casein and gelatin, which are currently widely used, show almost satisfactory performance in terms of resolution, but because alkali is used to increase solubility in water, dark reactions cause dark Hydrolysis of the resin progresses even in places, and the quality gradually deteriorates to the point where it becomes unusable. Furthermore, since it contains a dichromate such as ammonium dichromate as a photocrosslinking agent, drainage equipment is required for disposal. Furthermore, the stainability depends largely on the film thickness, and the staining conditions require high temperature and low pH for a long period of time. Not only does the resin film become thicker and the amount of ultraviolet rays required to cure the resin (exposure amount) increases, but also the light is transmitted through diffraction to areas that are blocked by the mask. is irradiated, so the resolution decreases. Therefore, the film thickness of the resin is required to be as thin as possible. Therefore, the dyeability of the resin used in the color element dyeing layer must be such that it can achieve a dyeing concentration sufficient to obtain the necessary spectral characteristics with a thin film thickness, and at low temperatures and in a short period of time. . Therefore, like casein and gelatin,
Resins that require a film thickness of 0.8 μm or more are unsuitable. Means for Solving the Problems In order to solve the above problems, the present invention uses a high-resolution dyeing photosensitive resin that can be developed with water, can be dyed at low temperatures, near neutral pH, and in a short time, as a color element colored layer. The present invention provides a method for producing a color filter using the present invention. That is, the present invention relates to a monomer having a structure of N-vinyl-2-pyrrolidinone and a quaternary amine and having a polymerizable unsaturated bond, and a compound having the following structure.

[Formula] A photosensitive resin made by adding a water-soluble bisazide compound as a crosslinking agent to a terpolymer of R ₁ = -H, CH ₃ R ₂ = -CnH _2o+1 (n = 1 to 8) as a substrate. In this method, a resin pattern is formed by coating the resin on top, selectively exposing it to light, and developing it with water, and then dyeing this pattern to form a color filter. Function The photosensitive resin for dyeing used in the present invention is made by the following molecular design. That is, it has a structure formed by ternary copolymerization of a compound having a photosensitive function, a compound having a dyeing function (nearly pH neutral), and a compound having a function of adjusting solubility in water. Specifically, N-vinyl-2-pyrrolidinone, a water-soluble compound that easily reacts with a crosslinking agent when exposed to ultraviolet rays, was used as the photosensitive compound, and a compound with a quaternary amine structure was used as the compound with a dyeing function. A compound having a polymerizable unsaturated bond was used. Further, in order to adjust the water solubility, a hydrophobic compound having the following structural formula was used.

[Formula] R ₁ = -H, CH ₃ R ₂ = -C _o H _2o+1 (n = 1 to 8) By using such resin, dyeing can be done in a short time with a thin film thickness, and unnecessary equipment is required. It becomes possible to obtain a color filter having a highly accurate fine dyeing pattern without using the above method. Example A compound having a quaternary amine structure and a polymerizable unsaturated bond is 2-hydroxy-3-methacryloxypropyltrimethylammonium chloride. Methacroyloxyethyltrimethylammonium chloride Examples include. Examples of hydrophobic compounds that adjust water solubility include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, and propyl acrylate. Water-soluble and dyeable photosensitive resins made by copolymerizing the three types of compounds mentioned above are extremely stable, and even those with crosslinking agents can withstand storage for more than three months if stored in the dark. can. A crosslinking agent that reacts with ultraviolet light is sodium 4,4'-diazidostilbene-2,2'-disulfonate. Sodium 2,6-bis-(4'-azidobenzal-)4-methylcyclohexanone-2,2'-disulfonate Sodium 1,3-bis-(4'-diazobenzal-)2-propanone-2,2'-disulfonate Sodium 2,6-bis-(4'-azidobenzal-)cyclohexanone-2,2'-disulfonate Examples include. If the molar ratio of N-vinyl-2-pyrrolidinone contained in the resin is less than 30%, the photosensitivity is low, and the photosensitivity is inferior to casein or gelatin-dichromate-based resins. Furthermore, if the molar ratio of the compound having a quaternary amine structure is less than 5%, the dyeing property is poor and it is not possible to obtain the necessary optical density at a film thickness of 0.8 μm or less. If it exceeds 30%, the solubility in water is high and the film tends to become rough.
If the molar ratio of the hydrophobic compound used to adjust the solubility in water exceeds 60%, the solubility in water will drop significantly and development in water will become impossible, so this range is desirable. Further, if the molar ratio is less than 10%, the solubility is high and development with water becomes difficult. Therefore, the composition ratio of the resin of the present invention is such that the molar ratio of N-vinyl-2-pyrrolidinone is
30%-85%, molar ratio of compound having quaternary amine structure and polymerizable unsaturated bond is 5-30
%, the molar ratio of the compound to adjust the solubility in water is preferably 10% to 60%. Since the resin used in the present invention is a terpolymer of each element, the required performance can be brought out by changing the composition ratio depending on the application. When this photosensitive resin is applied onto a glass plate, irradiated with ultraviolet rays, and then dyed to produce a color filter, it has the following advantages compared to gelatin or casein-dichromate based photosensitive resins. I have it. (1) The same optical density can be achieved with a thinner film thickness compared to gelatin or casein-dichromate photosensitive resins. Table 1 shows the results.

[Table] (2) In gelatin or casein-dichromate photosensitive resins, the dyed part and the part that undergoes photocrosslinking are the same, so the dyed part changes when exposed to light. However, in the resin used in the present invention, the parts exhibiting each function are independent of each other, so the dyeing is not affected by light irradiation. Table 2 shows the change in film thickness to obtain the same optical density when the amount of light irradiation changes.

[Table] As can be seen from the above results, the resin used in the present invention can obtain the same optical density with a film thickness of 50% to 30% compared to conventional resins, and therefore is affected by light diffraction during light irradiation. is reduced and the resolution is increased. Furthermore, staining can be carried out at room temperature in a short time. Next, examples of dyes capable of dyeing this photosensitive resin will be given. (1) Red dyes include Suminol, Milling,
Scarlet G (Sumitomo Chemical), Cibacron Scarlet G-P (Ciba Geigy), Cibacron Pronto Scarlet (Ciba Geigy), Suminol Fast Red G
(Sumitomo Chemical), Sumilite Splat Red
4BL (Sumitomo Chemical), Aminyl Red E-2BL
(Sumitomo Chemical), Aminyl Red E-3BL (Sumitomo Chemical), Azide Scarlet 901 (Sumitomo Chemical), Suminol Milling Scarlet
FG (Sumitomo Chemical), Suminol Milling Orange SG (Sumitomo Chemical), Suminol Fast Orange PO (Sumitomo Chemical), Maxilon
Red GRL (Ciba Geigy), Eriosin Scarlet RE (Ciba Geigy),
Mikawan Brilliant Red 8BS (Mitsubishi Chemical), Acid Light Scarlet
Examples include GL130% (Mitsubishi Chemical) and Kayanol Milling Red RS125 (Mitsubishi Chemical). (2) As green dyes, Suminol, Milling,
Gilliant Green 5G (Sumitomo Chemical), Acid Gilliant Milling Green G
(Sumitomo Chemical), Acid Brilliant Milling
Green B (Sumitomo Chemical), Mication Olive Green 3GS (Ciba Geigy), Kayanol Milling Green 5GW (Nippon Kayaku),
Sooriidazole Green P-GG (Hoechst), Paper First Green 5G
(Beichel) etc. (3) As blue dyes, Sumilite, Spra,
Turquoise Blue G (Sumitomo Chemical), Cibacron Blue 3G-A (Ciba Geigy), Cidochlorane Blue 8G (Ciba Geigy), Procion Turquoise H-A (CIC), Kayachi Onturquois P-A (Nippon Kayaku), Kayathion Turquoise P-NGF (Nippon Kayaku), Sumikalon Blue E-FBL (Sumitomo Chemical), Sumikalon Brilliant Blue S-BL (Sumitomo Chemical), Suminol Leveling Sky Blue R Extra Conc (Sumitomo Chemical), Orazole Blue GN (Ciba Geigy), Maxion Blue 3GS (Mitsubishi Chemical), Maxion Blue 2GS (Mitsubishi Chemical), Kayanol Milling Blue GW (Nippon Kayaku), Kayasil
Examples include Sky Blue R (Nippon Kayaku). Next, more detailed examples of the resin used in the present invention will be described. N-vinyl-2-pyrrolidinone 30.0g 2-hydroxy-3-methacryloxypropyltrimethylammonium chloride 10.0g Methyl methacrylate 15.0g Azobisisobutyronitrile 0.2g Methanol 250ml Pour the above liquid into a three-neck flask, After purging the reaction vessel with nitrogen for 1 hour, the temperature was raised to 65°C, and polymerization was carried out with stirring for 6 hours. After the polymerization was completed, the mixture was precipitated in a large amount of ethyl acetate, washed with petroleum ether, and then dried under reduced pressure to remove the solvent. After drying, dissolve in water and add 4,
A photosensitive resin solution was prepared by adding 5 mg of sodium 4'-diazidostilbene-2,2'-disulfonate per 1 g of resin. FIGS. 1 to 3 are cross-sectional views showing each step of an embodiment of the present invention for forming a color separation filter for a solid-state image sensor. The photosensitive resin solution described above is uniformly applied onto the transparent substrate 1 using a spinner. Next, irradiate ultraviolet rays through a mask (surface illuminance 4.5MW/cm ² ×
5 seconds) to form a latent image of pattern part 2 of the first color, which is the part that should feel red, and then soak it in water at 25℃.
It was developed for 30 seconds to reveal it. Next, pattern part 2
was stained under the following conditions. Suminol Milling Red G 1.0wt% Acetic acid 2.0wt% Pure water Dyeing temperature, time 25°C, 4 minutes A transparent intermediate film (methyl methacrylate polymer) 3 was placed on top of the dyed pattern area 2 using a spinner in the same way. Apply. FIG. 1 is a sectional view showing this state. Next, the photosensitive resin solution is uniformly applied again and exposed through a mask in the same manner as the first color to form a latent image of the second color pattern part 4, which is the part that should feel green, and then soaked in water at 25°C. Developed for 30 seconds.
Thereafter, the pattern portion 4 was dyed under the following conditions. Suminol Milling Brilliant Green 5G 2.0wt% Acetic Acid 2.0wt% Pure Water Staining temperature, time 25°C, 6 min The above-mentioned transparent interlayer film 5 was applied on top of this film. FIG. 2 is a sectional view showing this state. Furthermore, the above photosensitive resin solution was uniformly applied on the upper part, exposed and developed in the same manner as the first and second colors to form a third color pattern part 6, which is a part that should feel blue. Next, this pattern part 6
was stained under the following conditions. Cibachloran Blue 8G 1.0wt% Acetic acid 2.0wt% Pure water Dyeing temperature and time 25°C for 5 minutes Top coat 7 was formed on top of this to obtain the color separation filter shown in Figure 3. By the above method, a mosaic color separation filter for a solid-state image sensor can be formed. FIG. 4 shows a color separation filter formed directly on a solid-state image sensor 9 made of a semiconductor substrate or the like using the above method, and the same parts as in FIG. 3 are given the same numbers. Reference numeral 8 indicates a light detection section of the solid-state image sensor 9. Effects of the Invention The present invention provides a method for manufacturing a color filter in which a monomer having a structure of N-vinyl-2-pyrrolidinone and a quaternary amine and having a polymerizable unsaturated bond is used in a colored layer of a color element and A terpolymer of compounds with the structure

[Formula] By using a photosensitive resin composition formed by adding a water-soluble bisazide compound to R ₁ = -H, -CH ₃ , R ₂ = -C _o H _2o+1 (n = 1 to 8). , compared to conventional casein and gelatin-dichromate-based photosensitive resins.
A filter with a thin film thickness of 30% to 50% and the same optical density can be obtained under dyeing conditions of short time around room temperature. Furthermore, since the required optical density can be obtained with a thin film thickness, the resolution is increased and pattern alignment is facilitated, and at the same time it can be developed with water and does not cause environmental pollution. Furthermore, by changing the ratio of the three types of compounds, the film thickness, dyeing concentration, dyeing conditions, etc. can be selected depending on the application. In this manner, the present invention greatly contributes to the mass production of color filters having highly accurate fine patterns.

[Brief explanation of drawings]

1, 2, and 3 are cross-sectional views showing the manufacturing process of a color filter according to an embodiment of the present invention, and FIG.
The figure is a sectional view of a solid-state imaging device using a color filter according to the present invention. 1... Board, 2... First color pattern, 3...
...intermediate film, 4...second color pattern, 5...intermediate film, 6...third color pattern, 7...top coat, 8...photodetection section, 9...solid-state image sensor.

Claims (1)

[Claims] 1 A monomer having a structure of N-vinyl-2-pyrrolidinone and a quaternary amine and having a polymerizable unsaturated bond, and a compound having the following structure [Formula] R ₁ A photosensitive resin made by adding a water-soluble bisazide compound as a crosslinking agent to a terpolymer of =-M, -CH ₃ R ₂ = -C _o H _2o+1 (n = 1 to 8) is placed on a substrate. Manufacture of a color filter characterized by comprising a step of coating, a step of forming a pattern of the resin by selectively exposing the resin and developing with water, and a step of dyeing the formed pattern to form a dyed pattern. Method.