JPS63226602A - Color filter - Google Patents

Abstract

PURPOSE:To obtain a filter having excellent optical characteristic by coloring one pattern of a color filter with the symmetrical or asymmetrical 2:1 chromium complex salt dye of an azo compd. expressed by the formula. CONSTITUTION:The azo compd. expressed by the formula is prepd. by bringing the diazonium salt of aminocarboxylic acids and pyrazole deriv. into reaction with each other. A 1:1 chromium complex dye is prepd. from one kind thereof and a chromium compd. and further, the same or different kind of the azo compd. expressed by the formula is acted therewith to prepare the symmetrical or asymmetrical 2:1 chromium complex dye. Layers to be colored are dyed by the dyes having the prescribed optical characteristics to provide colored layers successively via protective films. In the formulas, R1 is H, Cl, SO3H, SO2CH3, SO2C2H5, SO2NHCH3, SO2NHC2H5, NO2; R7 is CH3, etc.; R2, R3, R4, R5, R6 respectively independently denote H, Cl, CH3, C2H5, OCH3, SO3H. The color filter having the excellent optical characteristics is obtd. by this constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to color filters. For more details,
This invention relates to color filters with excellent optical properties used in liquid crystal display devices, color separation devices, and sensors.

The conventional method for producing color filters using dyeing methods involves dyeing the surface of a substrate such as glass or silicon wafer in a striped or mosaic pattern (pattern), such as a thin transparent synthetic resin film with cationic groups or gelatin. A coat of protein-based natural polymer substances such as casein, glue, etc. is provided as a colored film, and this is dyed (colored) using a dye.
The basic principle is to do so. The following three methods are known as specific manufacturing processes for color filters.

(1) After a film to be colored is provided on the surface of the substrate, it is exposed to light through a mask and developed, and the resulting pattern is dyed to form a colored layer. Next, a non-colored protective coating film is provided over the entire surface, and a second colored film is provided thereon by the same procedure as described above. Thereafter, colored layers are sequentially laminated as necessary.

(2) After forming a film to be colored on the surface of the substrate, it is exposed to light through a mask, developed, and the resulting pattern is dyed to form a colored layer. After that, the dye is fixed and resisted with tannic acid, etc. Apply. A second coating to be colored is provided by a similar operation. Thereafter, if necessary, a colored layer is formed on the same substrate surface.

(3) A film to be colored (a film to be colored) is provided on the surface of the substrate. After a positive resist layer is provided thereon, the colored film exposed in a pattern is dyed by exposure and development through a mask, and then the positive resist layer is peeled off to form a colored portion. The operations after forming the positive resist layer are repeated to dye the same colored film in a plurality of colors in a desired pattern.

Color filters manufactured by the above process are usually manufactured using the three primary colors R (red), Ge), and B (blue), or the three complementary primary colors Y (purchased M (magenta),
It has a colored layer colored C (cyan) (M may be omitted). The most important property required of a color filter is its optical property, and the spectral properties of each colored layer greatly control the value of the final product.

In this regard, liquid crystal display devices equipped with color filters are highly resistant to heat treatments encountered during the manufacturing process and to light applied during use as a final product, resulting in loss of desired optical properties. There should be no.

It goes without saying that the dyes applied must also have good solubility and solubility in water and be stable for long periods in acidic dye baths. By the way, since protein-based natural polymer substances such as gelatin, casein, and glue have cationic groups, they can be dyed (colored) with water-soluble anionic dyes. In addition, when using a photocurable synthetic resin base material instead of these, it is possible to dye it with a water-soluble anionic dye in the same way as protein-based natural polymer substances, since it is necessary to retain cationic groups in the resin component. will be done.

Problem to be Solved by the Invention In order to obtain dyes with desired optical properties and reliability (mainly good resistance to heat and light) and solubility in water, a large number of water-soluble anionic dyes are used. They have been considered alone or in combination. However, in the case of complementary yellow dyes, it is particularly difficult to select a dye that satisfies the above-mentioned desired properties, and at present no satisfactory dye has been found. Furthermore, with respect to the green color obtained by combining a yellow anionic dye with a cyan or green anionic dye, a desirable green color cannot be obtained because the desired yellow dye has not been found.

The spectral characteristics required for the desired yellow dye are 400-4
Wavelength (λv=50) that gives 50cm transmittance of a colored film dyed so that the transmittance at 5Qnm is 1% or less
is at 520±lQnm, which means that the transmittance in the wavelength region longer than 550 Jim is as high as possible.For this purpose, dyes belonging to the color index Acid Orange 149 are conventionally used.
This dye has the disadvantage of poor light resistance. Color Index Acid Yellow 161 is a dye that satisfies both optical properties and light resistance, and has been used for a long time, but this dye has poor solubility in water and the aqueous solution becomes cloudy, making it particularly difficult to dye. When the dye bath is made acidic, it becomes cloudy and the dye precipitates, resulting in poor dyeing reproducibility and short life of the dye bath.

Under these circumstances, there is a demand for the development of dyes for color filters that have excellent optical properties and are also excellent in solubility in water and in heat resistance and light resistance of dyed films.

Means for Solving the Problems The present inventors have developed the above-mentioned optical characteristics and excellent reliability (
As a result of our earnest efforts to find a color filter that has good light resistance and heat resistance, we discovered that a certain metal-containing azo compound also has excellent solubility in water, and as a result, dyed (colored) color filters can meet the optical properties described above. The inventors discovered that the method also has excellent reliability, leading to the present invention.

That is, the present invention provides a color filter in which a patterned colored film is placed on a substrate, in which at least one pattern is a symmetrical or asymmetrical 2:1 chromium azo compound represented by the following formula (1) as a free acid. Color filter No.2 or -No2 is characterized by being colored with a complex salt dye, and R7 represents -CH or -〇.Also, Rt, Rs, R4, R5 and R6 each independently represent -H1-α , representing CH3, C2H5,0CHs or -3o3H).

The color filter of the present invention will be explained in detail.

The symmetrical or asymmetrical 2:1 chromium complex dye of the azo compound represented by formula (1) used in the color filter of the present invention is generally produced as follows.

First, the azo compound of formula (1) used in producing a symmetrical or asymmetrical chromium complex dye can be obtained, for example, by reacting a diazonium group of aminocarboxylic acids with a pyrazole derivative by a conventional method.

One part of the azo compound of the formula (1) and a chromium compound (from this, a 1:1 chromium molten salt dye is first formed, and then the same or different azo compound of the formula (1) is reacted to form a symmetrical or asymmetrical 2= 1 chromium complex salt dye is obtained, but the formula (1
) to a 1:1 chromium complex dye, for example, by converting an azo compound of formula (1) in the presence of an acid medium in a closed or open vessel with at least 1 molar equivalent of a chromium donor and at the boiling point of the medium or at 100°C. It can be carried out by reacting at a temperature exceeding . In this case, trivalent chromium salts such as chromium formate, chromium acetate, chromium fluoride, chromium chloride or chromium sulfate can be used as chromium donors. Also this 1:1
The chromium complexation can be carried out in an aqueous medium optionally in the presence of an organic solvent such as alcohol, butanol or formamide.

The conversion of the 1=1 chromium complex dye to the 2:1 chromium complex dye is then carried out as follows. When a symmetrical 2:1 chromium complex dye is desired, the same type of azo compound of formula (1) used to prepare the 1:1 chromium complex dye, or when an asymmetric 2:1 chromium complex dye is desired, The azo compound of formula (1) different from the azo compound of formula (1) used to produce the 1:1 chromium complex dye is used, and the reaction is carried out in an aqueous solution or suspension in an acidic solution. This can be done by heating in the presence of a binder. The reaction temperature is preferably 6
It is 0-100°C. Examples of acid binders that can be used are alkali metal hydroxides or carbonates or acetates, such as sodium hydroxide, sodium carbonate or sodium acetate or the corresponding lithium, potassium or ammonium salts. The reaction may sometimes be accelerated by the addition of organic solvents such as alcohols or formamide or by the addition of surfactants. The molar ratio of the azo compound of the formula (υ) to the 1=1 chromium complex dye is usually 1:0.85 to 1:1.
The ratio is more preferably 1:1.

Next, an example of the color filter of the present invention will be explained using the drawings. Figure 1 fa) to (h) are glass plates (substrate)
FIG. 2 is a conceptual diagram showing a method of manufacturing a color filter using a lamination method in which colored layers of different colors are laminated on top. In Fig. 1, l is a glass plate, 2 is a thin film of photocurable resin etc. provided by spin-coding, 2' is a film to be colored by photo-curing 2 through a mask, 2'' is a colored layer, 3 is a non-staining protective film, 4
5 is a photomask, 5 is a second colored layer, and 6 is a non-stainable protective film.

A mixture of a protein-based natural polymer such as gelatin, casein, or glue and a dichromate such as ammonium dichromate or a photocurable synthetic resin composition having a cationic group is spin-coated on the glass plate 1. , applied by a method such as roller coach ink to a thickness of 0.2 to 2
A photocurable thin film 2 of μ is provided (FIG. 1(b)).

Next, a photomask 4 having a predetermined pattern on the thin film
The exposed area is cured by irradiating it with ultraviolet light. (1st
Figure (C)).

Next, the unexposed portions are removed by developing with water or the like to form a colored layer 2' having a predetermined pattern (FIG. 1(d)). 5. To obtain a first color, a first colored layer 2'' is formed by dyeing using a dye having predetermined optical properties (FIG. 1(e)).

Next, a non-staining protective film 3 is applied over the entire surface (Fig. 1(f)).
.

Next, a photocurable coating layer for obtaining a colored layer is provided on the protective film 3 in the same manner as described above, and is exposed to light through a mask and developed to form a colored layer in a predetermined pattern. ,
In order to obtain a second color, a second colored layer 5 is formed by dyeing with a dye having predetermined optical properties (FIG. 1(g)).
.

Next, a non-staining protective film 6 is provided on the entire surface (Fig. 1 (h)).
. This operation can be repeated to form a colored layer of a third color, or even a colored layer of a fourth color.

In direct-cut color separation color filters for solid-state imaging devices, a flattening layer is provided on the silicon substrate on which the light detection section, etc. is provided, and a colored layer is formed on top of it using the same procedure as described above. The same material as the non-staining protective film can be used for the planarization layer.

The colored layers include primary colors R (red), G (green), B (blue),
In some cases, complementary colors Y (yellow), M (magenta),
A case of C (cyan) is also possible.

Green can also be obtained by a combination of yellow and cyan, by layering a yellow colored layer and a cyan colored layer, or by dyeing yellow or cyan and then dyeing again with cyan or yellow dye. It can also be formed by a double dyeing method.

In the present invention, a symmetrical or asymmetrical azo compound represented by the general formula (1) 2: It is essential to use a 1-chromium complex dye or a mixture thereof, and because the yellow colored layer or green colored layer has good spectral transmission characteristics and resistance such as light resistance and heat resistance, it is suitable for color separation. As a color filter, it is possible to obtain faithful color reproducibility, and as a color display car) - as a filter, it has good color balance and excellent durability.
- Images can be obtained.

Protein-based natural polymer substances such as gelatin, casein, and glue as the film to be colored in the present invention will be explained. Gelatin is an animal protein that is irreversibly made water-soluble by boiling collagen with water. Gelatin is extracted from animal bones, skin, pus, etc. by boiling it with water. Casein is a phosphorus protein that is the main component of milk. A dichromate such as ammonium dichromate is added to an aqueous solution of these natural proteins, and the coated layer is cured by applying ultraviolet rays after uniformly coating it on a substrate such as glass using spin coating or roller coating. , a water-insoluble film is formed.

Further, examples of synthetic resins having a cationic group as a coloring material used in the present invention include the following.

That is, a photoreactive resin composition consisting of a polymer having a photoreactive unsaturated group and a quaternary ammonium base in its side chain, a photopolymerization initiator, and a solvent, or this resin composition further containing one
A photoreactive resin composition containing a compound having two or more photoreactive unsaturated groups in its molecule is applied to the surface of a substrate, and then irradiated with active light such as ultraviolet rays to cause a reaction and form a film. These are things that have been done. In this case, polymers having a photoreactive unsaturated group and a quaternary ammonium base in their side chains are, for example, (N,N-dimethylamino)ethyl acrylate, (N,N-diethylamine)ethyl acrylate,
), allyl bromide, 3-chloro-2-methylpropene, p-chloromethylstyrene in homopolymers or copolymers obtained by polymerizing monomers having tertiary amino groups such as (N,N-dimethylamino)propylacrylamide, etc. , 3-chloro-2-hydroxypropyl methacrylate and other unsaturated compounds having an active halogen atom. Examples of compounds having two or more photoreactive unsaturated groups in one molecule include ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate,
Examples include neopentyl glycol diacrylate and trimethylolpropane trimethacrylate. As the photoreaction initiator, 2-ethylanthraquinone, benzophenone, etc. can be used. Further, the solvent may be any solvent as long as it can dissolve the polymer, photoreaction initiator, etc. well, and for example, 2-methoxyethanol, 2-ethoxyethanol, toluene, xylene, etc. can be used.

Such a photoreactive resin composition is applied to the surface of a substrate and cured by irradiation with actinic light such as ultraviolet rays to obtain a film.

Examples of photocurable anionic dye-dyeable synthetic resins are not limited to the above examples (a polymer containing a quaternary ammonium salt as one component, a photocrosslinking agent,
For example, a cationic group-containing polymer to which a diazo compound, azide, or diazide compound has been added, or a photocrosslinking group such as a chalcone, cinnamic acid, azide, or stilbazole group has been introduced into the polymer is dissolved in water or an organic solvent. It may also be a resin composition that has been prepared.

Symmetrical or asymmetrical 2:1 of the azo compound represented by formula (1)
For dyeing (coloring) the film using a chromium complex dye, for example, a dipping method or a printing method is used, and a dipping method using an aqueous solution is particularly convenient. In this case it is usually 0.1
A base material provided with the above film in a dye bath at 10 to 100°C in which 1 to 10 g of a symmetric or asymmetric 2:1 chromium complex dye of the azo compound of formula (1) is dissolved in 1 t of water, preferably 1 to 10 g. After soaking for 10 seconds or more for about 60 minutes, the sample is taken out, washed with water, and dried. The cyan-colored film thus obtained exhibits optical properties preferable as a color filter.

A method for providing a non-staining protective film is a negative-type 7-otoresist, for example, a resin composition obtained by adding a photo-crosslinking agent such as a diazo compound to an acrylic or polyvinyl alcohol-based polymer, or a photo-crosslinking group such as chalcone or cinnamic acid. A method is employed in which a resin composition, etc., in which acrylic or polyvinyl alcohol-based polymer is introduced in advance, is dissolved in water or an organic solvent, applied by spin coating, and cured by irradiation with ultraviolet rays.

In the present invention, glass, plastic sheets, silicon wafers, etc. can be used as substrates on which the coating to be dyed is provided, after being pretreated with a silane coupling agent or the like or provided with a flattening layer, if necessary. Ru.

"Example" The present invention will be explained in more detail by way of examples.

Example 1 KFCR-500 (gelatin aqueous solution manufactured by Fuji Pharmaceutical Co., Ltd.) on optical glass (high purity glass plate with excellent light transmittance)
4 parts of ammonium dichromate and 1 part of an 8% aqueous solution of ammonium dichromate were mixed and the degassed photosensitive liquid was coated with a spin code method to form a film with a thickness of lμ.
After pre-baking at 80°C for 10 minutes, it was applied using a mask alignment device MA-10 model (manufactured by Mikasa) through a mask with a predetermined number of turns.
After exposure with an energy amount of 00 mJ/d, 40°
Developed in warm water at C. The gelatin film was then post-baked at 120°C for 10 minutes to harden the gelatin film.

Next, it was immersed for 5 minutes at 60°C in a 0.5% aqueous solution of C, I, Acid Blue 185 adjusted to pH 5K with acetic acid, washed with water, and dried to form a first cyan colored layer.

Next, FVR-GIO (an oil-soluble negative photoresist produced by Fuji Pharmaceutical Co., Ltd.) was applied using a spin code method to a film thickness of 0.5μ, and after prebaking at 120°C for 10 minutes, using an ultra-high pressure mercury lamp. It was exposed to light at an energy level of 55 mW/cr/l, and after rinsing, it was post-baked at 15,000 for 20 minutes to form a resist dyeing layer.

Next, a photosensitive gelatin layer was prepared in the same manner as described above, exposed and developed to form a dyeable layer with a specific pattern, and pi was adjusted to 5 with acetic acid. 5 at 60°C in a 0.2% aqueous solution of the compound of formula (2) below.
Dyeing was done by soaking for a minute, and a second colored layer was applied.

This compound has excellent solubility in water, remains completely transparent even when acetic acid is added, and no precipitate was formed even after being left at 60'C for 2 weeks.

Next, the same photosensitive composition as the above-mentioned resist dyeing layer was applied to a film thickness of 0.5 μm.
A protective film was formed by spin-coding and exposing under the same conditions. The obtained color filter consisted of two colors, yellow and cyan, and was suitable as a color filter for a solid-state image sensor.

When the spectral transmittance curve of the yellow colored part was measured, it was found that 400
The transmittance in the region of ~4501 m is 3% or less, and the wavelength at which the transmittance is 50 cm, λT = 50. was 512mm. This value did not change at all even when the dye bath for obtaining yellow color was left at 60°C for two weeks before use, and the reproducibility and working stability were good.

Ultraviolet cut filter (L-40 manufactured by HOYA Corporation)
) to a standard fade meter (FAL-3H model manufactured by Suga Test Instruments), the optical density (-1o
The rate of decrease in gT) was 1 inch, and there was almost no fading.

The symmetrical 2:1 chromium complex salt of formula (2) used in this example was synthesized as follows.

A 1:1 chromium complex dye prepared by reacting diazotized 2-aminobenzoic acid-5-sulfonic acid with 1-(3'-chlorophenyl)-3-methyl-5-pyrazolone followed by chromation. 0, 1 mol, and dilazotized 2-aminobenzoic acid-5-sulfone l['1-(
0.1 mol of the dye prepared from 3'-chlorophenyl-3-methyl-5-pyrazolone was suspended in lt of water.

After adding IN sodium hydroxide solution until the pH value was 7, the mixture was heated to 8 oeCK. The resulting bright yellow solution was heated to pH = 7.0 until no metal-free dye was detected. The mixture was stirred at 80°C. Then sodium chloride was added to precipitate a 2:1 chromium complex, which was separated and dried.

This complex dye λmax: 440nm (water) It had the structure of

Comparative example The dyes used to obtain the second colored layer are C, I.

The spectral transmittance curve of the yellow part of the color filter prepared by the same method as in Example 1 except that Acid Yellow 161 was used is that of Example 1 when the dye bath immediately after preparation was used.
It was very similar to the curve obtained in .

However, the solubility of C, I, Acid Yellow 161 in water is poor, and the solution is translucent, and when acetic acid is added to adjust the pH, it becomes cloudy and forms a viscous precipitate over time. Therefore, when the dye bath was left at 60°C for two weeks and then subjected to dyeing, the precipitates stuck to the film surface of the dyed object in spots. In addition, the spectral transmittance curve of the area where no precipitate is attached varies depending on the area and is unevenly colored.
The wavelength at which the tinting power decreases and the transmittance is 50 cm, λT = 50.
Compared to the case where the dye bath immediately after preparation was used, the wavelength was shifted to the shorter wavelength side by '3 to lQ nm depending on the location of the colored part.

Example 2 Toluene・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・69■ (N,N-dimethylamino)ethyl methacrylate...
...30 parts azoisobutyronitrile...
・・・・・・・・・・・・・・・・・・・・・・・・ 1 part of the liquid with the above composition was treated with SO'C in a nitrogen atmosphere for 8 hours,
100 parts of poly(N,N-dimethylamino))ethyl methacrylate solution are obtained. After adding 15 parts of chloromethylstyrene to 50 parts of this solution at room temperature and reacting for 16 hours,
This was dissolved in 260 parts of 2-ethoxyethanol. Further, 916 parts of Irgacure 651 (manufactured by Ciba Geigy, a photopolymerization initiator) was added and dissolved to obtain a cationic group-containing photosensitive resin composition.

Next, the glass surface described above was washed with acetone, dried, and then K
Apply a 10% ethanol solution of BM503 (silane coupling agent, Shin-Etsu Chemical Co., Ltd. Membrane) and dry at 110°C for 5 minutes.
Heat and dry for a minute, then wash the surface with acetone.
It was dried and used as a base material for coating.

The above-mentioned photosensitive resin composition was applied to the surface of this coating base material to a film thickness of approximately 1 micron using a spin code method, and after drying at 100°C for 20 minutes, ultraviolet rays were applied at 80 Wa using a high-pressure mercury lamp.
tt 7cm, irradiated for 4 seconds to harden the coating film, and then
It was post-baked at 0°C for 30 minutes to form a hardened layer to be dyed.

A positive resist Az111S (manufactured by Hoechst Japan ■) was applied to a film thickness of 1 μm using the spin foot method, and
After pre-baking at °C for 20 minutes, the mask alignment device MA-10
After exposure using a mold (manufactured by Mikasa ■) with an energy amount of 300 millijoules/d, a positive resist developer AZ303 (
(manufactured by Hoechst Javan ■) diluted 4 times with water for 90 seconds at room temperature, and then washed with water.

Next, in a 0.1% aqueous solution of "Kayanor Milling Red G RA" (manufactured by Nippon Kayaku ■, red acid dye), 50%
After immersion at °C for 5 minutes, washing with water, treatment with ethyl acetate for 2 minutes, and treatment with N-methylpyrrolidone for 5 seconds to remove the positive resist, washing with water and drying to form a patterned first red colored area. I got it.

Next, in the same manner as described above, a positive resist layer is provided, exposed to light through a mask, and developed to expose the dyeable resin layer in a portion other than the first colored portion.

60'C in a 0.2% aqueous solution of the compound of formula (3) below.
After soaking for 2 minutes in C.1, Acid Blue 185 0.
After dyeing by immersing in a 5% aqueous solution at 60° C. for 10 minutes, the positive resist was peeled off to obtain a second colored layer colored green. Note that a 0.2% aqueous solution of the compound of formula (3) described below for obtaining a yellow color was completely transparent and no precipitate was formed even when it was left at 6000° C. for one month.

Next, another part of the same dyeable resin layer was soaked in a 0.1% aqueous solution of C,1, Acid Blue 90 for 50 min in the same manner as described above.
After dyeing by immersion at °C for 5 minutes, the positive resist was peeled off to obtain a third colored layer colored blue.

Next, the same photosensitive composition as the resist dyeing layer of Example 1 was applied to a film thickness of 0.
The color filter of the present invention was obtained by spin-coding the film to a thickness of 5μ, exposing it to light under the same conditions, and providing a protective film.

The obtained color filter consisted of three colors, red, green, and blue, and was suitable for use in liquid crystal color televisions. When the spectral transmittance curve of the green colored part was measured, the wavelength showing the maximum transmittance was 520 nm, and the wavelength showing the yellow side transmittance of 50 nm, λT = 50. is 513 copies m
The transmittance in the region of 1400 to 450 nm was 3 cm or less. In addition, the optical density (-10 gT) at the maximum absorption wavelength of 513 nm on the yellow side after 200 hours of exposure to a standard fade meter (FAL-3H model, manufactured by Suga Test Instruments) through an ultraviolet cut filter (L-40, manufactured by HOYA Corporation) The rate of decline was 2 inches, with almost no fading.

The compound of the following formula (3) used in Example 2 was synthesized as follows.

Diazotized 2-aminobenzoic acid-5 sulfone ff
wo1-(3'-chlorophenyl)-3・-methyl-5-
0.11 mol of 1:1 chromium complex dye prepared by reaction with pyrazolone followed by chromation and diazotized 2-aminobenzoic acid and 1-phenyl-3-
0.1 mol of the dye prepared from methyl-5-pyrazolone was stirred in one portion of water. The resulting suspension was then adjusted to pH 6-7 with aqueous ammonia and heated to 90°C. The soon-forming yellow solution was stirred at I) H=7.90° C. until no metal-free dye was detected. Sodium chloride was then added to precipitate the asymmetric 2:1 chlorocomplex dye, which was then separated and dried. This complex dye had the following structure.

Comparative Example The yellow dye used to obtain the second green colored part was C.
, 1. The spectral transmittance curve of the green colored part of the song filter produced by the same method as in Example 2 except that Acid Orange 149 was used was similar to that in Example 1, but
As a result of the light emitting test described in Example 1, significant discoloration was observed with a reduction rate of 58%, and the green-colored area was discolored to blue-green with strong cyan because the balance between yellow and cyan was disrupted.

Examples 3 to 16 A symmetrical or asymmetrical 2:1 chromium complex salt dye was synthesized according to Example 1 or Example 2 using the azo compound shown in the ■ column or ■ column of the table as the azo compound of formula (1). Using this complex salt dye (λmax in water is shown in column 1 of the table), a oak filter consisting of two colors, yellow and cyan, was obtained in substantially the same manner as in Example 1.

Effects of the Invention A color filter that is used in liquid crystal display devices, color separation devices, sensors, etc. and exhibits good reproducibility, excellent optical properties, and durability, especially in the yellow or green region when combined with a cyan dye. was gotten.

[Brief explanation of drawings]

In FIGS. 1(a) to (h), 1 Glass plate 2 Photocurable thin film 2' Colored film 2" First colored layer 3 Non-staining protective film 4 Photomask 5 Second colored layer 6 Non-staining protective film 7 Developing tank 8 Staining tank 9 Represents the irradiation lamp. ,・S′1 ・・°・2゛; Shocking evening ,! Patent applicant Nippon Kayaku Co., Ltd. ＾ I-＾ ＾
＾d、OOで口11-1FIJA

Claims (1)

[Claims] 1. In a color filter in which a patterned colored film is placed on a substrate, at least one pattern is a symmetrical or asymmetrical 2:1 azo compound represented by the following formula (1) as a free acid. A color filter characterized by being colored with chromium complex dye. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1) (In formula (1), R_1 is -H, -Cl, -SO_3
H, -SO_2NH_2, -SO_2CH_3, -SO
_2C_2H_5, -SO_2NHCH_3, -SO_
2NHC_2H_5 or -NO_2, R7 is -CH_
Represents 3 or ▲There are mathematical formulas, chemical formulas, tables, etc.▼, respectively. Moreover, R_2, R_3, R_4, R_5 and R_6 are each independently -H, -Cl, -CH_3, -C_2H_
5, -OCH_3 or -SO_3H. )