JPS6289904A - Color filter - Google Patents

Abstract

PURPOSE:To obtain the titled filter having excellent durable resistance to light and heat and with the less browning property of a pigment by forming a colored resinous film with a colored substrate resinous layer contg. modified polyvinyl alcohol having a cationic group in the molecule. CONSTITUTION:The colored resinous layer is formed by dyeing the substrate resinous layer contg. modified polyvinyl alcohol having a cationic group in the molecule. The content of the cationic group in the modified polyvinyl alcohol having the cationic group in the molecule is preferably regulated to 0.1-15mol% and most preferably to 0.5-10mol%. The polymer used as the substrate resin of the colored resinous layer of the color filter is singly used or can be used as the mixture with a public-known substrate resin of gelatin, casein, polyvinyl alcohol, etc., and the polymer has excellent coated film performance, adhesion with the substrate, dyeability, resolving power, pattern reproducing property, sensitivity, heat resistance, light resistance, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a color filter suitable for use in a color image sensor-1 liquid crystal display or the like.

[Background of the Invention] Conventionally, there has been a method for manufacturing color filters for color separation used in color image sensors-1 liquid crystal displays, etc.
For example, a dyeing method as described in Japanese Patent Publication No. 52-17375 has been adopted. This staining method is usually carried out by the following method. First, a photosensitive liquid, which is a water-soluble resin imparted with photosensitivity, is uniformly applied to a predetermined substrate such as glass or a device, and dried to form a photosensitive film.

Using photolithography technology, a desired pattern of relief such as stripes or mosaics is formed, and this relief portion is dyed with a dye having predetermined spectral characteristics to form a colored resin layer of the first color. . Next, an intermediate layer for preventing color mixture is formed thereon or a fixing treatment is performed. Furthermore, in order to form colored resin layers of the second and subsequent colors, similar operations are repeated to form a predetermined colored resin layer laminate, and then a transparent protective layer is formed as the uppermost layer to obtain a color filter.

As the base resin of the colored resin layer, gelatin, casein,
Water-soluble resins such as polyvinyl alcohol, polyvinyl acetate derivatives, cellulose derivatives, polyacrylamide derivatives, and derivatives thereof are known. The photosensitive solution contains at least one of these water-soluble resins and a photosensitizer (such as a dichromate, a diazo compound, and a diazide compound).
This is a coating liquid containing a water-soluble photosensitive composition composed of a photocuring agent). The properties required for this photosensitive liquid are as follows:
There are coating film performance, adhesion to the substrate, dyeability, resolution, pattern reproducibility, sensitivity, etc., and gelatin, casein, and polyvinyl alcohol are often used as materials that satisfy these properties. For example, dichromate is added to an aqueous gelatin solution to impart photosensitivity.
Although it can be sufficiently exposed with a high-pressure mercury lamp and has photosensitivity in the visible range, the absorption in the visible range disappears after development (hardening), so it has extremely good properties as a photosensitive liquid.

On the other hand, photosensitive solutions made of water-soluble resins such as gelatin, casein, and polyvinyl alcohol have poor storage stability, insufficient dyeing properties, and the need to keep the solution at a constant temperature during coating or dyeing. There are several drawbacks, such as the need for heating, which makes manufacturing difficult to control.

A method of mixing and using other synthetic polymer compounds as a water-soluble resin for color filters has also been proposed. For example, those using copolymer latex (Japanese Unexamined Patent Publication No. 53-4
No. 7227) A method using a monopolymer mordant (Japanese Unexamined Patent Publication No. 134611/1983) is known. However, when these synthetic polymer compounds are used together,
The dyeing concentration may be insufficient, or the polymer compound and photocuring agent (e.g. dichromate) may react and harden and aggregate.
These polymer compounds and the aforementioned gelatin.

Poor compatibility with casein, polyvinyl alcohol, etc.
When mixed, phase separation or aggregation may occur,
There is a problem that it is difficult to obtain a homogeneous film.

[Object of the Invention] An object of the present invention is to provide an improved color filter.

An object of the present invention is to provide a color separation filter that does not have the above-mentioned drawbacks, especially as a color separation filter for use in image sensor-1 liquid crystal displays and the like.

Another object of the present invention is to provide a color filter that has excellent durability against light and heat and has low browning properties.

[Summary of the Invention] The present invention provides a color filter including at least one colored resin layer laminated on a substrate, wherein the colored resin layer is a base resin layer containing modified polyvinyl alcohol having a cationic group in the molecule. The present invention provides a color filter characterized in that it is made by dyeing.

The content of cationic groups in the above-mentioned modified polyvinyl alcohol having cationic groups in the molecule is preferably in the range of 0.1 to 15 mol%, and particularly preferably in the range of 0.5 to 10 mol%. .

[Effects of the Invention] The polymer used as the base resin of the colored resin layer of the color filter of the present invention can be used alone or in a mixture with known base resins such as gelatin, casein, polyvinyl alcohol, etc., and has excellent coating film performance. , excellent in adhesion to substrates, dyeability, resolution, pattern reproducibility, sensitivity, heat resistance, light resistance, etc.

Therefore, the color filter of the present invention is particularly useful as a color separation filter for use in image sensor-1 liquid crystal displays and the like.

[Detailed Description of the Invention] The main feature of the color filter of the present invention is that modified polyvinyl alcohol having a cationic group in the molecule is used as the base resin component of the colored resin layer. The above-mentioned modified polyvinyl alcohol may be used alone as a base resin component, or may be used in combination with a known base resin.

Examples of the cationic group contained in the modified polyvinyl alcohol used in the present invention include groups represented by the following general formula.

General formula (I) (However, R1, R2 and R3 represent a hydrogen atom or a lower alkyl group, and A is a linking group) General formula (II) R4 R5 (However, R4, R5, R6 and R7 are each Represents either a hydrogen atom or a lower alkyl group,
A is a linking group, and General formula (IV) (wherein R11, R12, l (13 and R14 each represent a hydrogen atom, a lower alkyl group, or a phenyl group, and X- is an anion) dicar, 1 Breath V) 1O-A-N-R16 (However, RI5 and lli+6 represent a hydrogen atom or a lower alkyl group, and A is a linking group) 2J
I[(ヱD-! 1O-A-N-R18* x- I7 (However, R17, l(+8 and lli19 each represent either a hydrogen atom or a lower alkyl group,
A is a linking group, and X is an anion) General formula (VII) N + l(21 1(2G (However, l (20 and R21 represent a hydrogen atom or a lower alkyl group) General formula (VII) VIH) ■ N+ R23・X (However, R22, R23, and R24 each represent either a hydrogen atom or a lower alkyl group, and X- is an anion.) has 1 carbon
-6 alkyl groups (methyl, ethyl, propyl, butyl, pentyl and hexyl). Note that both the lower alkyl group and the phenyl group may contain a substituent.

Modified polyvinyl alcohol containing a cationic group as described above is disclosed in, for example, JP-A-59-107345, and is known per se.

Modified polyvinyl alcohol containing a cationic group as described in L can be easily obtained by, for example, introducing a vinyl compound having a cationic group described above and copolymerizing it when producing polyvinyl alcohol by a polymerization reaction. can be manufactured.

Examples of the above vinyl compounds with cationic groups include:
The following compounds may be mentioned.

As a compound having a cationic group of general formula (I), N
-(2-dimethylamino/ethyl)acrylamide, N-
(2-dimethylaminoethyl)methacrylamide, N-
(3-dimethylaminopropyl)acrylamide, N-
(3-diethylaminepropyl)acrylamide, N-
(3-dimethylaminopropyl)methacrylamide, N
-(3-diethylaminopropyl)methacrylamide,
N-(1,1-dimethyl-3-dimethylaminopropyl)acrylamide, N-(1,1-diethyl-3-dimethylamino/butyl)acrylamide, N-(1-methyl-1,3-diphenyl-3-diethylamine propyl)
Methacrylamide, N-(3-methylethylaminopropyl)methacrylamide, N-methyl-N-(3-dimethylaminopropyl)acrylamide, N-(2,2-
dimethyl-3-diethylaminopropyl)acrylamide, N-(2,2-dimethyl-3-dimethylaminopropyl)crotonic acid amide, N-(3,3-dimethyl-4
-dimethylaminobutyl) methacrylamide, N-(3
-methylaminopropyl)acrylamide, N-(aminoethyl)methacrylamide, and inpropylmethacrylamide.

-. Examples of the compound having a cationic group of general formula (II) include compounds obtained by quaternizing the compound of general formula (I) with a known quaternizing agent.

Examples of the compound having a cationic group of general formula (III) include ■-vinylimidazole, l-vinyl-2-methylimidazole, 1-vinyl-2-ethylimidazole, 1
-vinyl-2-7enylimidazole and l-vinyl-2,4,5-)limethylimidazole.

As a compound having a cationic group of general formula (TV),
Examples include compounds obtained by quaternizing the compound of general formula (III) above using a known quaternizing agent.

Examples of the compound having a cationic group of general formula (V) include dimethylamine ethyl vinyl ether, dimethylaminopropyl ether and vinyloxyethylamine.

As a compound having a cationic group of general formula (VI),
Examples include compounds obtained by quaternizing the compound of the above general formula (V) with a known quaternizing agent.

The degree of saponification of the modified polyvinyl alcohol having a cationic group in the molecule used in the color filter of the present invention is preferably in the range of 30 to 100 mol%, and more preferably in the range of 50 to 99 mol%. preferable.

Further, the degree of polymerization of the modified polyvinyl alcohol is preferably 200 or more, and particularly preferably in the range of 500 to 5,000.

As mentioned above, the modified polyvinyl alcohol of the present invention can be used alone as a base resin, but it can also be used in combination with other known water-soluble polymer compounds.

When used in combination with the modified polyvinyl alcohol of the present invention, gelatin, albumin, casein, cellulose derivatives,
Examples include agar, sodium alginate, sugar derivatives, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide and its derivatives, polyvinyl acetate and its derivatives.

If necessary, two or more known water-soluble compounds may be mixed.

However, the content of the modified polyvinyl alcohol in the base resin layer is preferably 5% by weight or more and 30% by weight or less based on the amount of resin contained.

In the production of known color filters, a base resin and desired additives ( A coating solution containing a hardening agent such as potassium dichromate, etc.) is applied and dried to form a coating layer, and then this coating layer is used as a pattern mask (a photomask with a pattern such as a mosaic or stripe) to form a mosaic, stripe, etc. This is done by forming a base resin layer (relief), dyeing this base resin layer to make a colored resin layer (colored relief), and forming a protective layer on top of this colored resin layer. Two or more layers are laminated. In this case, each layer is often treated to prevent color mixture, or a color mixture prevention layer is provided between each layer.

The color filter of the present invention is manufactured according to the conventionally known techniques as described above, and there are no particular limitations on the manufacturing method.

The thickness of the base resin layer is preferably in the range of about 0.01 to 5 JLm, particularly preferably in the range of about 0.3 to 2 JLm.

Techniques for coloring the base resin layer are also already known. That is,
The base resin layer (relief) is dyed with a blue, green, red, cyan, magenta, or yellow dye to form a colored resin layer (color separation filter element).

Various dyes are already known as dyes used for this dyeing, and acid dyes, direct dyes, and reactive dyes are particularly preferred.

The dyes particularly preferably used in the present invention include:
List non-alkali metal dyes (i.e. those in which the alkali metal atoms of conventionally used alkali metal-containing dyes are replaced with organic cations such as pyridinium cations, ammonium cations, quinolinium cations, or hydrogen atoms). I can do it.

Note that in the production of ordinary color filters, various processing agents such as the above-mentioned curing agent or a rinsing liquid containing a buffering agent are used, but it is preferable to use those that do not contain alkali metals. In particular, it is desirable to take such consideration when manufacturing a micro color filter attached to the surface of a solid-state image sensor.

In the color filter of the present invention, it is easy to maintain a desired pH value of the colored resin layer, so its spectral transmission characteristics are improved, and furthermore, the excellent spectral transmission characteristics are stably maintained for a long period of time. There is.

Next, Examples and Comparative Examples of the present invention will be shown.

[Comparative Example 1] A photosensitive liquid having the following composition was coated on a transparent glass substrate using a spinner so that the film thickness after drying was 1.0 pm, and dried at room temperature for 15 minutes to form a base resin-containing coating layer. .

A1 gelatin 10g ammonium dichromate 1g water
A pattern mask consisting of a mosaic pattern was placed on top of this 100mfL coated layer and adhered in vacuum, and then exposed to a 500W high-pressure mercury lamp for 40 seconds (
This was then immersed in warm water at 43°C for 10 minutes and developed to dissolve and remove the non-crosslinked portions of the coating layer to form a mosaic base resin layer (relief). Created.

Next, this relief was immersed in a cyan dyeing solution with the following composition at 43°C.
It was immersed in water for 8 minutes and dyed.

Eiji JL-ku Copper-reduced phthalocyanine (tetra)sulfonic acid (tetra)pyridinium salt 0.5g pH approx. 6 buffer solution
1 sentence (containing 29.6g of ammonium acetate and 0.96mM of acetic acid per 1fL of water) Next, rinse this cyan-colored relief with a rinse solution (1fL of water).
After washing by immersion in (containing 1.5+nJ1 of acetic acid per fL) for 30 seconds, it was dried to obtain a cyan colored resin layer (cyan filter).

[Comparative Example 2] On the same transparent glass substrate as used in Comparative Example 1,
A cyan colored resin layer (cyan filter) was prepared by performing the same treatment as in Comparative Example 1, except that a photosensitive liquid having the composition shown below was coated and dried so that the film thickness after drying was 1.0 μm.
I got it.

Photosensitive liquid composition Polyvinyl alcohol Log (saponification degree 8
? , 8L degree of polymerization 2000) water
100m ammonium bichromate 2g However, the development conditions and staining conditions were changed as follows.

Development conditions: 25°C, 5 minutes Staining conditions: 25°C, 8 minutes [Example 1] On the same transparent glass substrate as used in Comparative Example 1,
A cyan colored resin layer (cyan filter) was prepared by carrying out the same process as in Comparative Example 1, except that a photosensitive liquid having the following composition was applied and dried so that the film thickness after drying was 1.0 gm.
I got it.

Photosensitive liquid composition Polyvinyl alcohol Ion pattern (degree of saponification 87.8%, degree of polymerization 2000) 20% aqueous solution of the following modified polyvinyl alcohol 5 m 11 10% aqueous solution of ammonium dichromate 0.8 m Standing tree
10m modified polyvinyl alcohol: Contains 3 mol % of trimethyl (3-methacrylamidopropyl) ammonium chloride as a copolymerized unit, saponification degree 97.5 mol %, viscosity 30 cp (4% aqueous solution, 20°
O, B type viscometer used).

[Example 2] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 1 except that modified polyvinyl alcohol was replaced with the following.

Modified polyvinyl alcohol: Contains 4 mol% of trimethyl (3-acrylamidoethyl) ammonium bromide as a copolymer unit, saponification degree 9
8.0 mol%, viscosity 35 cp (4% aqueous solution, 20°C, B
type viscometer).

[Example 3] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 1 except that the modified polyvinyl alcohol was replaced with the following.

Modified polyvinyl alcohol: Trimethyl(3-acrylamido-3,3-dimethylpropyl)ammonium chloride as a copolymerized unit3.
Contains 5 mol%, saponification degree 98° 1 mol%, viscosity 35 cp
(4% aqueous solution, 20'O.

(using a B-type viscometer).

[Example 4] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 1 except that the modified polyvinyl alcohol was replaced with the following.

Modified polyvinyl alcohol: Contains 3 mol% of l-vinyl-2-methylimidazole as a copolymerized unit, saponification degree of 96.8 mol%, viscosity of 28c
p (4% aqueous solution, 20°C, using a B-type viscometer).

[Example 5] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 1 except that the modified polyvinyl alcohol was replaced with the following.

Modified polyvinyl alcohol: Contains 2.5 mol% of N-methyl (3-dimethylaminopropyl) methacrylamide as a copolymerized unit, saponification degree of 97.5 mol%, viscosity of 22 cp (4% aqueous solution, 20°C,
(using a B-type viscometer).

[Example 6] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 1 except that the modified polyvinyl alcohol was replaced with the following.

Modified polyvinyl alcohol: Contains 2 mol% of trimethyl (3-methacrylamidopropyl) ammonium chloride as a copolymerized unit, saponification degree of 97.5 mol%, viscosity of 30 cp (4% aqueous solution, 20°C
, using a B-type viscometer).

[Example 7] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 1 except that the modified polyvinyl alcohol was replaced with the following.

Modified polyvinyl alcohol: Trimethyl (3-acrylamido-3,3-dimethylpropyl) ammonium chloride as a copolymerized unit 2.
Contains 5 mol%, saponified [98.3 mol%, viscosity 10 cp
(4% aqueous solution, 20°C, using a B-type viscometer).

[Evaluation of color filters] For each of the cyan filters obtained in Comparative Examples 1 to 2 and Examples 1 to 7, the spectral optical density at 630 nm was measured (using an MMSPil differential spectrophotometer manufactured by Olympus Optical ■). .

The results obtained are shown in Table 1.

Margin below Table 1 Optical density Staining index (D) CD/lumen) Comparative example 1 0.78 0.652
0.22 0.20 Example 1 1.
68 1.42 1.40 1.
4 3 2.08 1.6 4 1.80 1.8 5 1.65 1.5 6 1.56 1.3 7 1.56 1.2 In Table 1, the dyeing index is determined by the layer thickness of one filter layer ( gm
) divided by the optical density CD).

As is clear from the results in Table 1, the color filter of the present invention has a much higher dyeing index (D/pm, dyeing density per unit layer thickness) than the color filter of the comparative example. As a result, the color filter according to the present invention has a filter layer thickness that is smaller than that of the color filter of Comparative Example 1 (
It has been found that the layer can be made significantly thinner than conventional gelatin-based color filters. Due to this thinning,
Resolution is significantly improved and pattern reproducibility is improved. Another advantage is that processing time can be shortened.

[Example 8] On the same transparent glass substrate as used in Comparative Example 1,
A cyan colored resin layer (cyan filter) was prepared by carrying out the same process as in Comparative Example 1, except that a photosensitive liquid having the following composition was applied and dried so that the film thickness after drying was 1.0 gm.
I got it.

20% aqueous solution of modified polyvinyl alcohol of Example 1
5m9゜10% aqueous solution of ammonium dichromate 0.4m sample
15m sentence [Example 9] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 8 except that the modified polyvinyl alcohol was replaced with that in Example 2.

[Example 10] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 8 except that the modified polyvinyl alcohol was replaced with that in Example 3.

[Example 11] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 8 except that the modified polyvinyl alcohol was replaced with that in Example 4.

[Example 12] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 8 except that the modified polyvinyl alcohol was replaced with that in Example 5.

[Example 13] A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 8 except that the modified polyvinyl alcohol was replaced with that of Example 6. A cyan colored resin layer (cyan filter) was obtained in the same manner as in Example 8 except that the cyan resin layer was replaced with that of Example 8.

[Evaluation of Color Filters] Spectroscopic optical density measurements similar to those described above were performed for each of the cyan filters of Examples 8 to 14, and the results shown in Table 2 were obtained.

Margin below Table 2 Optical density Staining index (D) (D/lumen) Example 8 1.76 1.69
1.92 1.6 10 1.80 1.811 2
．． 10 2.112 1.53
1.713 1.26 1.414
1.26 1.4 As is clear from these results, it is clear that the modified polyvinyl alcohol containing a cationic group exhibits sufficient photosensitivity and a high dyeing index even when used alone.

[Example 15] A photosensitive liquid having the following composition was coated on a transparent glass plate to a thickness of 0.5 pm.

End section L1 or polyvinyl alcohol 10mJ1 (10%
Aqueous solution, saponified Jf 87.8g Degree of polymerization 2000) 20% aqueous solution of modified polyvinyl alcohol of Example 1
5g 10% aqueous solution of ammonium dichromate 0.8m water
This coated layer of 10 m thick was exposed to ultraviolet light through a mask having a striped pattern of the first filter color element, and then developed with cold water at 23° C. for 30 seconds to form a base resin layer (relief). Next, a staining treatment was performed at 40° C. for 2 minutes using a staining solution having the following composition.

Staining liquid composition water
1M Suminol Milling Brilliant Sky Blue SE O, 5g (Add acetic acid to adjust pH to 3.0) After dyeing, immerse in rinsing solution for 30 seconds, then wash, and then undergo two steps of tannic acid treatment and tartarstone treatment. Resist dyeing treatment consisting of the following treatments was carried out.

First resist dyeing treatment: Immerse in an aqueous solution of 2 g of tannic acid and 10 cc of acetic acid dissolved in 1 liter of water at 25°C for 2 minutes, then rinse with water for 1 minute.

Second treatment: Next, it was immersed in an aqueous solution of 5 g of tartarite and 2.5 cc of acetic acid dissolved in 1 liter of water at 25°C for 2 minutes, washed with water for 1 minute, and dried.

By the above operations, a first colored resin layer (filter element) was created.

Next, after beta-baking at 170°C for 20 minutes, a colored resin layer (filter element) for a second color was created using a photosensitive solution having the same composition as the first color and in the same manner as above (dry film thickness: 1.
(applied to Ogm). However, the staining process was performed at 25° C. for 4 minutes using the following staining solution.

and ``L4 Yusui''
1 sentence Kitten Green C-I 9 0.3g
0.5 g of Direct Fast Yellow BG (adjusted to pH 3, 4 by adding acetic acid) Furthermore, a colored resin layer (filter element) of a third color was created in the same manner as above (applied to a dry film thickness of 0.7 JLm). However, the dyeing process is 1. Using the following staining solution, 25
℃ for 6 minutes.

Staining liquid composition water
1 sentence Suminol Fast Red G 3g (
Add acetic acid to adjust the pH to 3.0) On top of this, add 1pm thick ethyl p-phenylene diacrylate and equimolar amount of 1.4-bis(β-hydroxyethoxy).
- An overcoat resin layer (covering layer) made of a copolymer with cyclohexanone (containing 2% by weight of 2-benzoylmethylene-1-methyl-β-naphthotizoline as a sensitizer) was provided, and then the coating layer was heated at 150°C for 10 I pre-baked it for a minute. The bonding pad portion and the dicing cut portion were covered thereon, and UV exposure was performed using a mask (exposure pattern) in which the pixel area was exposed. Next, the resin was developed with γ-butyrolactone, and the unexposed portions of the resin were eluted and removed. Then, post-baking was performed at 170°C for 40 minutes.

By the above method, a polychromatic optical color filter consisting of blue, red, and green was obtained.

[Example 16] A COD solid-state image sensor wafer whose surface was smoothed using a photosensitive resin having the same composition as the overcoat layer of Example 15 was prepared.

A single layer of multicolor color filter was formed on the smooth surface of this solid-state image sensor wafer in the same manner as in Example 15. next,
This solid-state image sensor wafer was cut and separated using a diamond cutter while being showered with water to obtain a color solid-state image sensor. The separated color solid-state image sensor is
Ultrasonic cleaning was performed using a solvent such as water, trichlene, or freon to remove chips and oil adhering to the surface.

The color solid-state image sensor obtained in this way is then transferred to the wire bonding process, but before the wire bonding, an observation under magnification with a microscope revealed that the overcoat layer and the colored resin layer No deterioration of filter function, such as membrane peeling, elution, decolorization, color mixing, or opacity, was observed.

Next, this was left in an oven at 200° C. for 3 hours, a thermotest was performed, and then observed under a microscope, but no change was observed here either. Therefore, it was found that the single layer color filter according to the present invention also has excellent heat resistance.

This is wire bonded and packaged, and C
When the device was installed in an OD color camera and a photographic test was conducted, it was confirmed that color images with good color reproducibility were reproduced on a cathode ray tube.

Claims (1)

[Scope of Claims] 1. A color filter comprising at least one colored resin film laminated on a substrate, the colored resin film comprising a base resin layer containing modified polyvinyl alcohol having a cationic group in the molecule. A color filter characterized by being made by dyeing. 2. The color filter according to claim 1, wherein the modified polyvinyl alcohol having cationic groups in its molecule has a cationic group content of 0.1 to 15 mol%. 3. The color filter according to claim 2, wherein the modified polyvinyl alcohol having cationic groups in its molecule has a cationic group content of 0.5 to 10 mol%. 4. The above cationic group has the formula (I), (II), (III)
, (IV), (V), (VI), (VII) or (VIII)
: ￥General formula (I)￥ ▲Mathematical formulas, chemical formulas, tables, etc.▼ (However, R^1, R^2 and R^3 represent a hydrogen atom or a lower alkyl group, and A is a linking group) ￥General formula (II)￥ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R^4, R^5, R^6 and R^7 each represent either a hydrogen atom or a lower alkyl group, and A is a linking group, and Represents either a hydrogen atom, a lower alkyl group, or a phenyl group) ￥ General formula (IV) ￥ ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (However, R^1^1, R^1^2, R^1 ^3 and R^1^4 each represent a hydrogen atom, a lower alkyl group, or a phenyl group, and X- is an anion) ￥General formula (V)￥ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R^1^5 and R^1^6 represent a hydrogen atom or a lower alkyl group, and A is a linking group.)
￥General formula (VI)￥ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R^1^7, R^1^8 and R^1^9 each represent either a hydrogen atom or a lower alkyl group. , A is a linking group, and X is an anion)
￥General formula (VII)￥ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R^2＾0 and R＾2＾1 represent a hydrogen atom or a lower alkyl group) ￥General formula (VIII)￥ ▲Mathematical formula , chemical formulas, tables, etc.▼ (However, R^2^2, R^2^3, and R^2^4 each represent either a hydrogen atom or a lower alkyl group, and X- is an anion.) The color filter according to claim 1 or 2, which is a cationic group represented by: 5. The color filter according to claim 1 or 2, wherein the content of the modified polyvinyl alcohol in the base resin layer is 5% by weight or more based on the amount of resin contained. 6. The color filter according to claim 1 or 2, wherein the content of the modified polyvinyl alcohol in the base resin layer is 30% by weight or less based on the amount of resin contained. 7. In the base resin layer, unmodified polyvinyl alcohol,
Claim 1 or 2 further contains at least one water-soluble resin selected from the group consisting of gelatin, casein, polyvinyl acetate derivatives, cellulose derivatives, and polyacrylamide derivatives. color filter.