JP3323677B2 - How to create a color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a color filter used in a liquid crystal display or the like, and more particularly to a method for forming a pattern pixel having a light shielding property.

[0002]

2. Description of the Related Art A color filter used in a full-color liquid crystal display has a light-shielding pattern pixel between each of R, G, and B pixels for the purpose of preventing light leakage and improving contrast. The light-shielding pattern pixels are formed using a metal film such as chromium or a material in which a black pigment or the like is dispersed in a photosensitive resin. In the case of a metal film such as chromium, the metal film is vapor-deposited on the entire surface of the glass substrate by means such as vapor deposition, and then a resist is applied, patterned, and etched to pattern the metal film. In this method, the process is very complicated, the yield is low, and there are problems in cost. On the other hand, a method of forming a pattern pixel having a light-shielding property using a photosensitive black resin in which a photosensitive resin and carbon are combined is known. In this case, in order to obtain a certain light-shielding property, a film thickness of several μm is required. It is necessary, and usually, to create a color filter, pattern pixels having light-shielding properties and R,
Since the G and B pixels have a certain degree of overlap at the present time, the surface of the color filter has irregularities. In order to obtain good flatness, a flattening layer is further provided thereon and the surface is polished.
Therefore, Japanese Patent Application Laid-Open Nos. Hei 3-209203 and Hei 4-6960 are disclosed.
For No. 2, a method of applying a black photosensitive resin layer on the entire surface after forming R, G, and B, exposing from the back surface, and forming a pattern pixel having a light shielding property in a gap between RGB is being studied. However, with these methods, it is very difficult to apply a black photosensitive resin layer between the R, G, and B pixels with the same film thickness as the R, G, and B over the entire surface. When a liquid crystal panel was prepared using the color filters described above, there was a problem that the cell gap was not uniform and display unevenness occurred.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a color filter having pattern pixels having good flatness and light-shielding properties over the entire surface. A second object of the present invention is to provide a method for easily and accurately forming a pattern pixel having a high light-shielding property.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to cover a multicolor pattern formed by pixels each having one of the three primary colors of light provided on a transparent substrate, and to shield the multicolor pattern by transfer onto the transparent substrate. Forming a photosensitive photosensitive resin layer, irradiating actinic rays through the transparent substrate, curing the light-shielding photosensitive resin layer in a portion where the multicolor pattern is not present, and developing the light-shielding photosensitive resin layer. Forming a pixel having a light-shielding property in a portion where the multicolor pattern does not exist, comprising:
The pixel having one of the three primary colors of light contains a compound represented by the following general formula I , and the light-shielding photosensitive resin layer
The light in the photosensitive wavelength region has one of the three primary colors of the light
This is achieved by a method for producing a color filter, wherein the transmittance after passing through the pixel is 2% or less .

[0005]

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Here, R ₁ is an amino group substituted with at least one hydroxyalkyl group or a group represented by the following general formula II. The hydroxyalkyl group preferably has 1 to 10 carbon atoms, and may further have an alkyl group, an aryl group, an alkoxy group or an aryloxy group.

[0007]

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R ₂ : hydrogen atom, alkyl group, aralkyl group, aryl group, alkoxy group, aralkyloxy group,
Aryloxy group, halogen atom, amino group or R
Represents a substituent represented by ₁ . When R ₂ is an amino group substituted with at least one hydroxyalkyl group represented by R ₁ ,
₁ and R ₂ may be the same or different. R ₃ represents an alkylene group which may have a substituent, and preferably has 1 to 10 carbon atoms. R _{4 is a} hydrogen atom, an alkyl group, an aralkyl group, an aryl group, an alkoxyalkyl group, an aralkyloxyalkyl group, an aryloxyalkyl group or a group represented by HO—R ₃ —, and R ₃ and R ₄ are nitrogen atoms May be included to form a 5- or 6-membered heterocyclic ring. Hereinafter, the present invention will be described in detail.

As a method for forming a multicolor pattern composed of one of the three primary colors of light, that is, R, G, and B pixels, on a transparent substrate, a dyeing method, a printing method, a pigment dispersion method, an electrodeposition method,
All known methods such as a transfer method can be used. When the light transmittance of the R, G, and B pixels in the photosensitive wavelength region of the light-shielding photosensitive resin exceeds 2%, the R, G,
It is preferable that a light absorber or the like is added to the B pixel to make the transmittance 2% or less. In this case, it is preferable to use a coumarin-based compound represented by the above general formula I as a light absorbing agent. These compounds have good light-absorbing properties and retain a light-absorbing performance of 25% or more even after heat treatment at 200 ° C. or more, and a multicolor pattern is formed using the photopolymerizable composition. In such a case, these photopolymerizations are not hindered. Note that the above-described heat treatment at 200 ° C. or higher is performed to further harden the pattern pixels as needed when the color filter is formed.

The following are specific examples of the coumarin compound represented by the general formula I, but the compounds which can be used in the present invention are not limited thereto.

[0011]

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[0012]

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[0013]

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[0014]

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[0015]

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[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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[0021]

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Among these compounds, compounds 1 and 5 having a light absorption capacity exceeding 70% even after heat treatment at 200 ° C. or more are preferable.

In the present invention, an image forming method such as a transfer material, a transfer method, and a developing method used in the step of forming a light-shielding photosensitive resin layer by transfer over the entire surface of the transparent substrate by covering the color filter is described in detail. Kaihei 4-208940
A transfer material and an image forming method having a separation layer and a photosensitive resin layer having low adhesion to a temporary support disclosed in Japanese Patent Application No. Hei. A photosensitive resin having a thermoplastic resin layer, an intermediate layer and a photosensitive resin layer on a temporary support disclosed in Japanese Patent Application No. 4-88875) and having the smallest adhesive force between the temporary support and the thermoplastic resin layer. Transfer material and image forming method
-72724 (Japanese Patent Application No. 3-9292, Japanese Patent Application No. 3-120)
223, having a thermoplastic resin layer, a separation layer, and a photosensitive resin layer disclosed in Japanese Patent Application No. 4-12980), wherein the transfer material and the image formation have the smallest adhesive force between the thermoplastic resin layer and the separation layer. Method, JP-A-5-80503 (Japanese Patent Application No. 3-153)
227, a temporary support disclosed in Japanese Patent Application No. 4-64870) has a thermoplastic resin layer, an intermediate layer and a photosensitive resin layer on the temporary support, and the adhesive force between the temporary support and the thermoplastic resin layer is low. Smallest photosensitive transfer material and image forming method, Japanese Patent Application No. 5-11
The light-shielding photosensitive resin composition containing two or more colorants and the method for forming a light-shielding image described in No. 0487 can be used.

When exposing through a transparent substrate (referred to as back exposure), the light source is selected according to the photosensitivity of the light-shielding photosensitive resin layer, and may be an ultrahigh-pressure mercury lamp, xenon lamp, carbon arc lamp, argon laser, or the like. Known light sources can be used.

At this time, when the light transmittance of the R, G, and B pixels with respect to the photosensitive wavelength region of the light-shielding photosensitive resin layer exceeds 2%, a light-shielding pattern having an optical density (OD) of 1.5 or more is used. In the case of forming a pixel, a light-cured light-shielding film may remain on the R, G, and B pixels, which may make it difficult to be practically used as a color filter. Therefore, the light transmittance of the pixel is 2% or less. As described above, it is preferable to add the compound represented by the general formula I.

Alternatively, only a desired wavelength region may be selectively extracted by using an optical filter. In this case, R, G, and R in the photosensitive wavelength region of the light-shielding photosensitive resin layer are used.
It is preferable to use an optical filter that transmits only light in a wavelength range where the light transmittance of each pixel B is 2% or less.

Both may be combined.

According to this method, the light-shielding photosensitive resin layer transferred onto each of the R, G, and B pixels does not substantially cure when exposed through the substrate, and is removed by a subsequent development process. It becomes possible. Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0029]

【Example】

Examples 1 to 43 On a polyethylene terephthalate film temporary support having a thickness of 100 µm, a coating solution having the following formulation H1 was applied,
After drying, a thermoplastic resin layer having a dry film thickness of 20 μm was provided.

Thermoplastic Resin Layer Formulation H1: Methyl methacrylate / 2-ethylhexyl acrylate / benzyl methacrylate / methacrylic acid copolymer (copolymer composition ratio (molar ratio) = 55/30/10/5, weight average molecular weight = 50,000) 15.0 parts by weight Polypropylene glycol diacrylate (average molecular weight = 822) 6.5 parts by weight Tetraethylene glycol dimethacrylate 1.5 parts by weight p-toluenesulfonamide 0.5 parts by weight Benzophenone 1.0 parts by weight Methyl ethyl ketone 30.0 Parts by weight

Next, the following formulation B1 was placed on the thermoplastic resin layer.
And dried to a dry film thickness of 1.6 μm.
An intermediate layer having a thickness of m was provided.

Intermediate layer formulation B1: 130 parts by weight of polyvinyl alcohol (PVA205 manufactured by Kuraray Co., Ltd., saponification rate = 80%) 60 parts by weight of polyvinyl pyrrolidone (PVP, K-90 manufactured by GAF Corporation) Fluorine-based surfactant (Asahi Glass) 10 parts by weight of distilled water 3350 parts by weight

On a temporary support having the thermoplastic resin layer and the intermediate layer, a coating solution having the following formulation C1 is applied.
After drying, a light-shielding photosensitive resin layer having a dry film thickness of 2 μm was formed.

Formulation C1: Benzyl methacrylate / methacrylic acid copolymer (molar ratio = 70/30, intrinsic viscosity = 0.12) 30.00 parts by weight Pentaerythritol tetraacrylate 7.40 parts by weight Michler's ketone 0.04 parts by weight 2 (Ο-chlorophenyl) -4,5-diphenyl imidazole dimer 0.40 parts by weight Carbon black 3.80 parts by weight Hydroquinone monomethyl ether 0.01 parts by weight Methyl cellosolve acetate 280.00 parts by weight Methyl ethyl ketone 140.00 parts by weight

Further, a cover sheet of polypropylene (12 μm in thickness) was pressed on the light-shielding photosensitive resin layer to prepare a light-shielding photosensitive transfer material. The photosensitive wavelength of the light-shielding photosensitive resin layer is from 350 nm to 420 nm, and the main photosensitive wavelength when an ultra-high pressure mercury lamp is used as a light source is 365 nm.
(I-line) and 405 nm (h-line), and the OD was 2.0 (measured using a Macbeth densitometer).

Further, red (R), blue (B) and green (G) colored photosensitive layer coating solutions having the compositions shown in Table 1 below were prepared.

Table 1: Formulation of coating solution for colored photosensitive layer R layer G layer B layer K layer ────── Benzyl methacrylate / 60.0 60.0 60.0 60.0 Methacrylic acid copolymer (Molar ratio = 73/27 Viscosity = 0.12) Pentaerythritol 43.2 43.2 43.2 43.2 Tetraacrylate Michler's ketone 2.4 2.4 2.4 2.4 2- (o-chlorophenyl 2.5 2.5 2.5 2.5 Diphenylimidazole dimer Irgasin red BPT (red) 5.4 --- --- --- Sudan blue (blue) --- 5.2 --- --- Copper phthalocyanine (green) --- --- 5.6 --- Carbon black (black) --- --- --- 5.6 Methyl cellosolve acetate 560 560 560 560 Methyl ethyl ketone 280 280 280 280 ─────────────────── ───────────────

The R-layer has an i-line transmittance of 0.5
%, Respectively, Compounds 1 to 43 are added,
The coating solutions for Examples 1 to 43 were used.

First, a color filter composed of R, G, and B pixels was formed on a glass substrate (thickness: 1.1 mm) using a coating solution containing Compound 1. Table 2 shows the transmittances of the i-line and the h-line in this case.

[0040]

The cover sheet of the light-shielding photosensitive transfer material is peeled off, and a light-shielding photosensitive resin layer surface is formed on a multicolor pattern surface on a multicolor pattern composed of R, G, and B pixels. VP-II).
kg / cm ² ) and heating (130 ° C.) for bonding, followed by peeling at the interface between the temporary support and the thermoplastic resin layer to remove the temporary support.

Next, the entire surface was exposed through an ultra-high pressure mercury lamp through a glass substrate. In this case, as shown in Table 2, the transmittance of the B pixel for h-line exceeds 2%.
Toshiba glass filter (UV) between the light source and the glass substrate
D36c). The exposure amount was 100 mj / cm ² . Thereafter, development was performed with a 1% aqueous solution of sodium carbonate to remove uncured portions, and pattern pixels having light-shielding properties were formed in gaps between the R, G, and B pixels. The completed color filter has good flatness with no overlap between the pattern pixels having light-shielding properties and the RGB pixels, and furthermore, substantially no light-shielding photosensitive resin layer remains on each of the RGB pixels. Did not. When similar steps were repeated using a coating solution containing Compounds 2 to 43, almost the same good results were obtained.

Comparative Example 1 A color filter was prepared in the same manner as in Example 1 except that no Toshiba glass filter (UVD36c) was provided at the time of exposure. In this case, the light-blocking photosensitive resin layer remained on the B pixel, and it was difficult to use it as a color filter.

Comparative Example 2 Red (R), blue (B), and red (R) having the composition shown in Table 1 of Example 1
Using a green (G) colored photosensitive layer coating solution (that is, a solution not containing the compound of the present invention), a glass substrate (thickness 1.1) was used.
mm), an R, G, B multicolor pattern was formed. Table 3 shows the transmittance of the i-line and the h-line in this case.

[0045]

A light-shielding photosensitive resin layer was provided on the multicolor pattern using a light-shielding transfer material in the same manner as in Example 1.
10 through Toshiba glass filter (UVD36c)
Exposure was performed at 0 mj / cm ² , followed by development with a 1% aqueous solution of sodium carbonate to remove uncured portions, thereby forming light-shielding pattern pixels in the gaps between R, G, and B pixels. In this case, since the transmittance of the R i-line exceeds 2%, a failure occurs in which the light shielding layer remains on the R pixel.

Example 44 A coating solution having the following formulation H1 was applied on a polyethylene terephthalate film temporary support having a thickness of 100 μm.
After drying, a thermoplastic resin layer having a dry film thickness of 20 μm was provided. Thermoplastic resin layer formulation H1: methyl methacrylate / 2-ethylhexyl acrylate / benzyl methacrylate / methacrylic acid copolymer (copolymer composition ratio (molar ratio) = 55/30/10/5, weight average molecular weight = 50000) 15.0 Parts by weight polypropylene glycol diacrylate (average molecular weight = 822) 6.5 parts by weight tetraethylene glycol dimethacrylate 1.5 parts by weight p-toluenesulfonamide 0.5 parts by weight benzophenone 1.0 parts by weight methyl ethyl ketone 30.0 parts by weight

Next, the following formulation B1 was placed on the thermoplastic resin layer.
And dried to a dry film thickness of 1.6 μm.
An intermediate layer having a thickness of m was provided. Separation layer formulation B1: Polyvinyl alcohol (PVA205, manufactured by Kuraray Co., Ltd., saponification ratio = 80%) 130 parts by weight Polyvinylpyrrolidone (PVP, K-90, manufactured by GAF Corporation) 60 parts by weight Fluorinated surfactant (Asahi Glass Co., Ltd.) 10 parts by weight of distilled water 3350 parts by weight

On a temporary support having the thermoplastic resin layer and the intermediate layer, a coating solution having the following formulation C1 was applied.
After drying, a light-shielding photosensitive resin layer having a dry film thickness of 2 μm was formed. Formulation C1: Benzyl methacrylate / methacrylic acid copolymer (molar ratio = 70/30, intrinsic viscosity = 0.12) 30.00 parts by weight Pentaerythritol tetraacrylate 7.40 parts by weight Michler's ketone 0.04 parts by weight 2 (ο- Chlorophenyl) -4,5-diphenyl imidazole dimer 0.40 parts by weight Carbon black 2.80 parts by weight Hydroquinone monomethyl ether 0.01 parts by weight Methyl cellosolve acetate 280.00 parts by weight Methyl ethyl ketone 140.00 parts by weight

Further, a cover sheet of polypropylene (thickness: 12 μm) was pressed on the light-shielding photosensitive resin layer to prepare a light-shielding photosensitive transfer material. The photosensitive wavelength of the light-shielding photosensitive resin layer is from 350 nm to 420 nm, and the main photosensitive wavelength when an ultra-high pressure mercury lamp is used as a light source is 365 nm.
(I-line) and 405 nm (h-line), and OD (optical density) was 1.5. (Measurement Using Macbeth Densitometer) Next, colored red, green, and blue photosensitive layers having the composition shown in Example 1 were formed. Using this, a glass substrate (thickness 1.1)
mm), R, G, B color filters were prepared. In this case, heat treatment was performed at 220 ° C. for 20 minutes for each color to completely cure each pixel. The obtained i-line and h of each color pixel
The line transmittance was as shown in Table 4.

[0051]

The covering sheet of the light-shielding photosensitive transfer material is peeled off, and the light-shielding photosensitive resin layer surface is coated with a laminator (VP-II manufactured by Taisei Laminator Co., Ltd.) on the color filter surface having the R, G, and B pixels. Pressurizing (0.8kg / c
m ² ) and bonding by heating (130 ° C.), and then peeling off at the interface between the temporary support and the thermoplastic resin layer, and removing the temporary support. Next, back exposure was performed using an ultra-high pressure mercury lamp from the side opposite to the color filter surface. At this time, as shown in Table 4, the transmittance of the h-line of B exceeded 2%.
Toshiba glass filter (UVD3) between light source and sample
The exposure amount was set to 100 mj / cm ² through 6c). Thereafter, development was performed with a 1% aqueous solution of sodium carbonate to remove unnecessary portions, and a light-shielding film was formed in each of the R, G, and B pixel gaps. The finished color filter had no overlap between the light-shielding film and the RGB layers, and had good flatness.

Example 45 A coating solution having the following formula H1 was applied on a polyethylene terephthalate film temporary support having a thickness of 100 μm.
After drying, a thermoplastic resin layer having a dry film thickness of 20 μm was provided.

Thermoplastic resin layer formulation H1: methyl methacrylate / 2-ethylhexyl acrylate / benzyl methacrylate / methacrylic acid copolymer (copolymer composition ratio (molar ratio) = 55 / 28.8 / 11.7 / 4.5; Weight average molecular weight = 80000) 15.0 parts by weight BPE-500 (polyfunctional acrylate manufactured by Shin-Nakamura Chemical Co., Ltd.) 7.0 parts by weight F177P (fluorinated surfactant manufactured by Dainippon Ink and Chemicals) 0.3 parts by weight methanol 30. 0 parts by weight methyl ethyl ketone 19.0 parts by weight 1-methoxy-2-propanol 10.0 parts by weight

Next, the following formulation B1 was placed on the thermoplastic resin layer.
And dried to a dry film thickness of 1.6 μm.
An intermediate layer having a thickness of m was provided. Separation layer formulation B1: Polyvinyl alcohol (PVA205, manufactured by Kuraray Co., saponification ratio = 80%) 130 parts by weight Polyvinylpyrrolidone (PVP, K-30, manufactured by GAF Corporation) 60 parts by weight Distilled water 2110 parts by weight Methanol 1750 parts by weight

On the temporary support having the thermoplastic resin layer and the intermediate layer, a coating solution having the following formulation is applied and dried to form a light-shielding photosensitive resin layer having a dry film thickness of 2 μm. Example 4 A cover sheet of polypropylene (12 μm thick) was pressure-bonded on the light-shielding photosensitive resin layer.
The light-shielding photosensitive transfer material No. 5 was prepared.

-Bensyl methacrylate / methacrylic acid copolymer (molar ratio = 70/30 viscosity = 0.12) 10.06 parts-Dipentaerythritol hexaacrylate 10.60 parts-2,4-bis (trichloromethyl) -6- [4- ( (N, N-diethoxycarboxymethyl) -3-fluoromophenyl] -S- 0.52 parts 1.70 parts ・ Hydroquinone monomethyl ether 0.01 parts ・ F177P (Surfactant manufactured by Dainippon Ink) 0.07 parts ・ Methyl cellosolve acetate 40.00 parts ・ Methyl ethyl ketone 125.0 parts

When the same steps as in Example 1 were repeated except that the light-shielding photosensitive resin layer was transferred onto the color filter prepared in Example 1, similar excellent results were obtained.

Hereinafter, as examples of the synthesis of the compound represented by the general formula I, the synthesis examples of the compound 1 and the compound 5 are shown.

Synthesis Example 1 (Synthesis of Compound 1) 3-Phenyl-7-[(6-chloro-4-diethylamino-s-triazin-2-yl) amino] coumarin 2
11. parts, N-butylamino-4-butanol
Two parts were added to 20 parts of tetrahydrofuran and reacted under reflux for 6 hours. The reaction product was poured into water, and the precipitated crystals were collected by filtration. After recrystallization from a mixed solvent of chloroform: ethyl acetate (1: 1), 20 parts of 3-phenyl-7-[[6
-(4-Hydroxybutylbutylamino) -4-diethylamino-s-triazin-2-yl] amino] coumarin was obtained. The melting point of the obtained compound was 124 to 126 ° C.

Synthesis Example 2 (Synthesis of Compound 5) 3-Phenyl-7-[(6-chloro-4-diethylamino-s-triazin-2-yl) amino] coumarin 2
1.1 parts and 12.7 parts of 3-hydroxymethylpiperidine were added to 20 parts of tetrahydrofuran and reacted under reflux for 3 hours. The reaction product was poured into water, and the precipitated crystals were collected by filtration. Recrystallization from ethyl acetate gave 22.2 parts of 3-phenyl-7-[[6- (3-hydroxymethylpiperidino) -4-diethylamino-s-triazin-2-yl] amino] coumarin. . The melting point of the obtained compound was 182-183 ° C.

[0062]

According to the method of the present invention, a photosensitive resin layer having a light-shielding property is transferred onto a multicolor pattern, and back exposure can be performed in a state where the light-shielding resin layer on the pixel is not substantially cured. Therefore, a color filter having excellent flatness can be easily formed.

Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G02B 5/20-5/28 CAPLUS (STN)

Claims (2)

(57) [Claims] 1. A light source comprising three light sources provided on a transparent substrate.
Forming a light-shielding photosensitive resin layer by transfer onto the transparent substrate over the multicolor pattern formed by the pixels having the primary color 1; irradiating active light through the transparent substrate;
A step of curing the light-shielding photosensitive resin layer in a portion where the multicolor pattern is not present, and a step of developing the light-shielding photosensitive resin layer to form a light-shielding pixel in a portion where the multicolor pattern does not exist; Wherein the pixel having one of the three primary colors of light is provided.
There contains a compound represented by the following general formula I, and wherein
The light in the photosensitive wavelength range of the light-blocking photosensitive resin layer is the light
2% transmittance after passing through a pixel having 1 of the three primary colors
A method for producing a color filter, characterized by the following . Embedded image Here, R ₁ represents an amino group substituted with at least one hydroxyalkyl group or a group represented by the following general formula II . Embedded image R _{2 represents a} hydrogen atom, an alkyl group, an aralkyl group, an aryl group, an alkoxy group, an aralkyloxy group, an aryloxy group, a halogen atom, an amino group or a substituent represented by R ₁ . When R ₂ is at least one amino group substituted with a hydroxy group represented by R _1, R ₁ and R ₂ may be the same or different. R ₃ represents an alkylene group which may have a substituent . R _{4 represents a} hydrogen atom, an alkyl group, an aralkyl group, an aryl group, an alkoxyalkyl group, an aralkyloxyalkyl group, an aryloxyalkyl group or a group represented by HO—R ₃ — . R ₃ and R ₄ may include a nitrogen atom to form a 5- or 6-membered heterocyclic ring. 2. The method for producing a color filter according to claim 1, wherein the light transmittance of the multicolor pattern pixel in the photosensitive wavelength region of the light-shielding photosensitive resin layer is 2% or less.