KR101352487B1 - Colored composition for color filters, color filter and method of manufacturing color filter - Google Patents

Abstract

The coloring composition for color filters contains a transparent resin, a coloring agent, and the organic solvent, The said organic solvent has a boiling point of 160 degreeC or more and less than 250 degreeC in 760 mmHg, and the conductivity in 25 degreeC is 0.001 nS / cm or more and 0.8 nS / cm It contains less than the organic solvent A, and the organic solvent B whose boiling point in 760 mmHg is 100 degreeC or more and less than 160 degreeC, and the conductivity in 25 degreeC is 0.8 nS / cm or more and less than 50 nS / cm. Organic solvent A is contained in a proportion of 5% by weight to less than 60% by weight based on the total amount of organic solvent, and organic solvent B is contained in a ratio of 40% by weight or more and less than 95% by weight based on the total amount of organic solvent. . Moreover, the color filter provided with the filter segment formed using this coloring composition, and the manufacturing method of a color filter are also disclosed.

Color filter, coloring composition, transparent resin, organic solvent, conductivity, filter segment

Description

Color composition for color filters, color filter and manufacturing method of color filter {COLORED COMPOSITION FOR COLOR FILTERS, COLOR FILTER AND METHOD OF MANUFACTURING COLOR FILTER}

This invention relates to the coloring composition used for the color filter used for a color liquid crystal display device, a color imaging tube element, etc., and the manufacturing method of the color filter and color filter using this coloring composition.

A color filter constituting a liquid crystal display (LCD), a color image tube element (CCD), or the like is produced by applying and drying a coating liquid (coloring composition for a color filter) on a transparent substrate and forming a coating film having a thickness of about 1 to 3 μm. do. As a coating method, there exist a spin coat method, the die coat method, etc., and it is used suitably according to the characteristic.

The spin coating method is a widely used method for forming a thin film on a relatively small sized substrate. The coating liquid is dropped on the center of the transparent substrate while the transparent substrate is rotated at a constant rotational speed, and the coating liquid is spread lightly by centrifugal force. It is a coating method of forming the coating film of desired thickness on the surface of a transparent substrate by controlling the rotation speed, rotation time, etc. of a transparent substrate suitable for a coating liquid. However, due to the principle of thinning the coating film by using centrifugal force by rotation, there is a drawback that the coating thickness of the rotation center portion and the peripheral portion of the transparent substrate becomes too thick as compared with the middle portion thereof.

In Japanese Patent Laid-Open No. 6-3521, a composition containing 50% by weight or more of a solvent having a boiling point and a vapor pressure in a specific range is described as a composition for spin coating with excellent coating film surface smoothness.

In the case where the size of the substrate is large, the die coating method is adopted in the method of rotating the substrate such as the spin coating method because the load on the apparatus is large.

The die coating method is a coating method which discharges a coating liquid from a slit, and forms the coating film of desired thickness on the surface of a transparent substrate, moving this slit. However, due to the mechanism, streaks in the vertical direction with respect to the advancing direction of the slit are likely to occur, and the coating liquid is exposed to the outside air at the slit openings to dry and solidify, resulting in agglomerations, and thus streaks in the coating advancing direction. This aggregate mixes with a coating material and becomes a coating film defect. Further, there is a problem that the outer periphery of the coating film swells and becomes thicker than the center of the substrate.

In order to solve the problem of unevenness of the coating film in the die coating method, various solutions are proposed in Japanese Patent Laid-Open No. 2003-55566, Japanese Patent Laid-Open No. 2004-346218, and Japanese Patent Laid-Open No. 10-104825. It has been.

Japanese Patent Application Laid-Open No. 2003-55566 and Japanese Patent Laid-Open No. 2004-346218 disclose a method of containing a solvent having a high boiling point to prevent the coating liquid from being exposed to the outside air to dry and solidify and thus not to generate aggregates. have.

Japanese Patent Application Laid-Open No. 10-104825 discloses a defect in which a tack property is increased by containing a high boiling point solvent and the adhesiveness (tack property) of the coating film is not solved even after the coating film drying process. The method of setting it as the solvent composition which exists in the range is described.

The following defects are observed because of the coating method such as the spin coat method or the die coat method and the properties of the coating liquid to be used.

Thickness nonuniformity: means that the thickness uniformity is insufficient, and that the "thickness uniformity (end)", that is, the thickness uniformity of the cross section is insufficient, and the "thickness uniformity (other than the end)", that is, the cross section just at the center of the substrate. There are two types of cases where the uniformity up to now is insufficient.

Striped spots: "Striped stripe spots", ie stripe-shaped spots that occur in a direction perpendicular to the direction of slit progression in the die coat method, and "vertical striped spots", ie, the direction of slit progression due to the aggregation of the slit openings in the die coat method. It is classified into two kinds of striped stains.

Tack property: A defect that the adhesion of the coating film does not disappear even after the coating film drying process such as natural drying, drying by heating, or vacuum drying.

Time-lapse instability of the coating liquid: Viscosity after time changes with respect to the initial viscosity of the coating liquid, that is, insufficient "time stability".

The problem is how to reduce such drawbacks. As described in the above-mentioned patent document, a method of simply containing a high boiling point solvent and a solvent composition having a evaporation rate within a specific range are not sufficient to solve the above drawbacks. not.

An object of the present invention is to provide a color filter coloring composition having reduced defects observed in a coating film by a spin coat method or a die coat method, and a filter segment formed using the same.

Means for solving the problem

According to the first aspect of the present invention, the resin contains a transparent resin, a coloring agent and an organic solvent, and the boiling point of the organic solvent at 760 mmHg is 160 ° C or more and less than 250 ° C, and the conductivity at 25 ° C is 0.001 nS / cm or more. The organic solvent A which is less than 0.8 nS / cm, and the organic solvent B whose boiling point in 760 mmHg has a boiling point of 100 degreeC or more and less than 160 degreeC, and the conductivity in 25 degreeC is 0.8 nS / cm or more and less than 50 nS / cm, A is contained in a ratio of 5% by weight to less than 60% by weight based on the total amount of the organic solvent, and organic solvent B is contained in a ratio of 40% by weight or more and less than 95% by weight based on the total amount of the organic solvent. A coloring composition for color filters is provided.

According to a second aspect of the present invention, there is provided a color filter, comprising a filter segment formed by using the coloring composition for color filters according to the first aspect of the present invention.

According to a third aspect of the present invention, the color filter coloring composition according to the first aspect of the present invention is coated on a substrate by a spin coat method or a die coat method to form a filter segment. A method is provided.

Effects of the Invention

Since the coloring composition for color filters of this invention contains the organic solvent A and the organic solvent B which have a boiling point and conductivity which respectively exist in a specific range in the specific ratio, they are excellent in stability over time. Moreover, the coating film which apply | coated this coloring composition has the thickness nonuniformity, the stripe | stain stain, and the remainder of tack property being reduced, and thickness is uniform and it has the outstanding performance.

Since the color filter of this invention is equipped with the filter segment formed from the coloring composition for color filters mentioned above, it has favorable quality.

When the coloring composition for color filters of this invention is used for manufacture of a color filter by a spin coat system and a die coat system, the formed filter segment has remarkably good quality.

To carry out the invention Best  shape

First, the coloring composition for color filters of this invention is demonstrated more concretely.

The coloring composition for color filters of this invention contains a transparent resin, a coloring agent, and the organic solvent. The organic solvent includes an organic solvent A having a specific boiling point and a specific conductivity and an organic solvent B having a specific boiling point and a specific conductivity. In the total organic solvent, the organic solvent A and the organic solvent B each occupy a specific ratio. On the other hand, in the present invention, the conductivity is measured using the Conductivity Meter Model 645 and 627 manufactured by Scientifica.

<Organic solvents>

The organic solvents used in the present invention are those in which the boiling point, conductivity, and weight ratio of each of the organic solvents constituting the organic solvent and the organic solvent B in the total organic solvents are each within a specific range. By using the organic solvent A and the organic solvent B which have these specific ranges of boiling point and conductivity in combination in the ratio of a specific range, the coloring composition for color filters with which the fault in the said conventional coating material was reduced can be comprised.

The boiling point of the organic solvent is related to the drying of the coloring composition for color filters (hereinafter, appropriately referred to as "coating liquid"), and when the solvent having a low boiling point is excessively high, the coating liquid dries in the opening of the slit of the die coater. When it becomes easy to generate | occur | produce a solid, and there are too many high boiling point solvents, even if it goes through the drying process of a coating film, the tack property (tackiness of a coating film surface) will not be eliminated. As a result, in addition to the adhesion of dust to the surface of the coating film, the mask may be contaminated in the proximity exposure machine. Further, if an organic solvent is to remain in a large amount in the coating film, the coating is a glass substrate, in particular in the surface developer can discard is peeled off from the glass substrate having SiO ₂ films.

In addition, the conductivity of the solvent contained in the coating liquid correlates with the conductivity of the coating liquid, except in the special case of adding a strong ionic material as the material constituting the coating liquid. If the conductivity of the coating liquid is too high, the affinity with moisture in the outside air increases and the moisture is absorbed to reduce the aging stability. On the contrary, if the conductivity of the coating liquid is too low, the chargeability of the liquid rises and the slit of the coating liquid increases. Unstable discharge property tends to cause coating irregularities (horizontal stripes). In addition, due to the charging of the coating liquid, the liquid tends to collect on the outer circumferential portion of the coating film, thereby increasing the ridge of the coating film outer peripheral portion.

In order to titrate the characteristic demonstrated above, in the organic solvent used for the coloring composition for color filters of this invention, the boiling point, conductivity, and the occupancy ratio in all the organic solvents of organic solvent A and organic solvent B become important.

That is, the organic solvent A is an organic solvent whose boiling point in 760 mmHg is 160 degreeC or more and less than 250 degreeC, and the conductivity in 25 degreeC is 0.001 nS / cm or more and less than 0.8 nS / cm.

The solubility parameter SP value δ _SA of the organic solvent A is preferably 8.5 (cal / cm 3) ^1/2 or more and 13.5 (cal / cm 3) ^1/2 or less. Here, the SP value of the organic solvent is described in various documents as a value obtained from the physical amount (evaporation heat, surface tension, etc.) of the organic solvent.

Moreover, it is preferable that organic solvent A has high solubility with respect to the transparent resin used for the coloring composition for color filters. That is, it is preferable that the difference between the solubility parameter δ _p of the transparent resin and the solubility parameter δ _SA of the organic solvent A is within 2.5 (cal / cm 3) ^1/2 . When the solubility parameter of the organic solvent and the value of the solubility parameter of the transparent resin are close to each other, the solubility of the resin can be increased to prevent the solidification of the coating solution. However, it becomes possible to supplement stability with time by using the organic solvent A which has the characteristic with low conductivity.

Examples of such an organic solvent A include cyclohexanol acetate, diethylene glycol diethyl ether, ethyl 3-ethoxypropionate, propylene glycol diacetate, carbitol acetate, butyl carbitol acetate and the like. In particular, cyclohexanol acetate is preferably used because the boiling point is not too high, the conductivity is low, and the solubility parameter is at a more appropriate value. That is, in the present invention, the organic solvent A is composed of cyclohexanol acetate alone, or cyclohexanol acetate and other organic solvent A (organic solvent A other than cyclohexanol acetate is referred to as "organic solvent A '". It is preferable to comprise by a mixture with). When organic solvent A is comprised by the mixture of cyclohexanol acetate and organic solvent A ', it is preferable that the ratio of cyclohexanol acetate in the mixture is 10 weight% or more (less than 100%). On the other hand, the solubility parameter of the mixture of the plurality of organic solvents is the solubility parameter of each organic solvent, the weight fraction of each organic solvent in the total amount of the organic solvent (the ratio of each organic solvent when the total weight of the organic solvent is 1). Can be obtained by adding the value obtained by multiplying.

Organic solvent B is an organic solvent having a boiling point at 760 mmHg of 100 ° C. or more and less than 160 ° C. and a conductivity of 25 ° C. or more and 0.8 nS / cm or more and less than 50 nS / cm. Examples of the organic solvent B include cyclohexanone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether and the like.

The organic solvent A accounts for 5% by weight or more and less than 60% by weight of the total amount of the organic solvent. If the ratio of organic solvent A is out of this range, even if it mixes with organic solvent B, all the faults of a conventional coating material cannot fully be improved. As for the ratio to the total solvent of the organic solvent A, 10 weight% or more and 50 weight% or less are more preferable.

The organic solvent B occupies the ratio of 40 weight% or more and less than 95 weight% based on the total amount of the organic solvent. If the ratio of organic solvent B is out of this range, even if it mixes with organic solvent A, all the faults of a conventional coating material cannot fully be improved. As for the ratio to the whole solvent of the organic solvent B, 40 weight% or more and 80 weight% or less are more preferable.

In this invention, organic solvents (organic solvent C) other than organic solvent A and B can be used. Examples of the organic solvent C include isoamyl acetate, tripropylene glycol methyl ether and the like. These can be used individually or in mixture. The organic solvent C may be used in a range not exceeding 40 wt% based on the total amount of the organic solvent.

In the coloring composition for color filters of this invention, it is preferable to use the organic solvent in the ratio of 500-5000 weight part with respect to 100 weight part of colorants, and it is more preferable to use it in the ratio of 1000-1500 weight part.

<Transparent resin>

The transparent resin used for the color composition for color filters of the present invention is a resin having a transmittance of preferably 80% or more, and more preferably 95% or more in the entire wavelength region of 400 to 700 nm which is the visible light region.

The transparent resin includes a thermoplastic resin, a thermosetting resin, a photosensitive resin, and the like, and these may be used alone or in combination of two or more thereof.

Examples of the thermoplastic resin include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride vinyl acetate copolymer, polyvinyl acetate, polyurethane resin, polyester resin, acrylic resin , Alkyd resin, polystyrene, polyamide resin, rubber resin, cyclized rubber resin, cellulose, polyethylene, polybutadiene, polyimide resin and the like.

Examples of the thermosetting resins include epoxy resins, benzoguanamine resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, melamine resins, urea resins, and phenol resins.

For example, the (meth) acryl compound and cinnamic acid which have reactive substituents, such as an isocyanate group, an aldehyde group, and an epoxy group, are made to react with the linear polymer which has reactive substituents, such as a hydroxyl group, a carboxyl group, and an amino group, of the said photosensitive resin, It is resin which introduce | transduced photocrosslinkable groups, such as a group and a styryl group, into linear polymer. Moreover, the linear polymer containing acid anhydrides, such as a styrene maleic anhydride copolymer and an alpha olefin maleic anhydride copolymer, is halved by the (meth) acryl compound which has hydroxyl groups, such as hydroxyalkyl (meth) acrylate. -Esterification is also used.

When patterning the coating film of the coloring composition for color filters by the photolithographic method, it is preferable to use alkali-soluble resin which can develop alkali as a transparent resin. As alkali-soluble resin, the methacrylic copolymer which uses methacrylic acid and 2-hydroxyethyl methacrylic acid as a copolymerization component from a viewpoint of patterning characteristic, pigment dispersibility, solvent resistance, etc. is preferable.

The transparent resin can be used in an amount of 30 to 700 parts by weight, preferably 60 to 450 parts by weight with respect to 100 parts by weight of the colorant in the color composition for color filters.

Meanwhile, in the present invention, the solubility parameter δ _p of the transparent resin is a value calculated by the Fedors method. When two or more types of resins (resin 1 to resin n) are mixed and used, the solubility parameter δ _p of the mixed resin is represented by the following formula. Calculated by (A).

(In formula (A),

δ _p : solubility parameter of the mixed resin

δ _p1 : solubility parameter of Resin 1

δ _p2 : solubility parameter of resin 2

δ _p3 : solubility parameter of Resin 3

------------------------------

δ _pn : solubility parameter of resin n

a ₁ : weight fraction of resin 1 in the mixed resin

a ₂ : weight fraction of resin 2 in the mixed resin

a ₃ : weight fraction of resin 3 in the mixed resin

------------------------------

a _n : weight fraction of resin n in the mixed resin)

<Coloring agent>

As a coloring material used for the coloring composition for color filters of this invention, an organic or inorganic pigment can be used individually or in mixture of 2 or more types. Among the pigments, pigments having high color development and high heat resistance, particularly pigments having high thermal decomposition resistance, are preferable, and organic pigments are usually used.

Hereinafter, the specific example of the organic pigment which can be used suitably for the coloring composition for color filters of this invention is shown by the color index number.

As a red coloring composition for forming a red filter segment, it is C.I. Pigment Red 7, 9, 14, 41, 48: 1, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2, 81: 217, 228, 227, 228, 240, 246, 254, 255, 264, 272 can be used. A yellow pigment and an orange pigment may be used in combination in the red coloring composition.

As a yellow coloring composition for forming a yellow filter segment, it is C.I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 20, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 86, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 125, 126, 127, 128, 129, 137, 138, 139, 147, 148, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, Yellow pigments, such as 181, 182, 185, 187, 188, 193, 194, 199, can be used.

Orange coloring compositions for forming orange filter segments include, for example, C.I. Orange pigments such as Pigment orange 36, 43, 51, 55, 59 and 61 may be used.

As the green coloring composition for forming the green filter segment, for example, C.I. Green pigments such as Pigment Green 7, 10, 36 and 37 can be used. A yellow pigment may be used in combination with the green coloring composition.

As a blue coloring composition for forming a blue filter segment, it is C.I. Blue pigments such as Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 60 and 64 can be used. The blue coloring composition includes C.I. Purple pigments, such as Pigment Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, 50, can be used together.

As the indigo coloring composition for forming the indigo filter segment, for example, C.I. Blue pigments such as Pigment Blue 15: 1, 15: 2, 15: 4, 15: 3, 15: 6, 16 and 81 can be used.

As the magenta coloring composition for forming the magenta filter segment, for example, C.I. Pigment violet 1, 19, C.I. Purple pigments and red pigments such as Pigment Red 144, 146, 177, 169 and 81 can be used. A yellow pigment may be used in combination with the magenta coloring composition.

Inorganic pigments include barium sulfate, zincated, lead sulfate, yellow lead, zinc sulfur, bengala (red iron (III) oxide), cadmium red, ultramarine blue, royal blue, chromium oxide green, cobalt green, amber, titanium black, synthetic iron black, Metal oxide powder, metal sulfide powder, metal powder, such as titanium oxide and iron tetraoxide, etc. are mentioned. Inorganic pigments are used in combination with organic pigments to ensure good applicability, sensitivity, developability, etc. while balancing saturation and lightness.

In addition, the coloring composition of this invention can be made to contain dye within the range which does not reduce heat resistance for coloring.

When disperse | distributing a coloring agent in transparent resin and an organic solvent, dispersion adjuvant, such as surfactant, a resin type pigment dispersing agent, and a pigment derivative, can be used suitably as a pigment dispersing agent. Dispersion aids are excellent in dispersibility of pigments and have a great effect of preventing re-agglomeration of pigments after dispersing. Therefore, in the case of using a coloring composition obtained by dispersing the pigment in a transparent resin and an organic solvent using a dispersion aid, Obtained. The pigment dispersant may be used in an amount of 0.1 to 40 parts by weight, preferably 0.1 to 30 parts by weight based on 100 parts by weight of the colorant in the coloring composition.

Surfactant as a dispersing aid used for pigment dispersion include polyoxyethylene alkyl ether sulfate, sodium dodecylbenzene sulfonate, alkali salt of styrene-acrylic acid copolymer, sodium alkylnaphthalin sulfonate, sodium alkyldiphenyl ether disulfonate, lauryl sulfate Anions such as monoethanolamine, lauryl sulfate triethanolamine, lauryl sulfate ammonium, stearic acid monoethanolamine, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene alkyl ether phosphate ester Surfactants; Nonionic surfactants such as polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether phosphate ester, polyoxyethylene sorbitan monostearate and polyethylene glycol monolaurate; Cationic surfactants such as alkyl quaternary ammonium salts and ethylene oxide adducts thereof; Amphoteric surfactants, such as alkylbetaine, such as alkyldimethylaminoacetic acid betaine, and alkyl imidazoline, and fluorine type and silicone type surfactant.

The resinous pigment dispersant is a resin having a pigment affinity site having a property of being adsorbed to the pigment and a site compatible with the transparent resin, and is adsorbed by the pigment to stabilize the dispersion of the pigment into the transparent resin. Specific examples of the resinous pigment dispersant include polycarboxylic acid esters such as polyurethane and polyacrylate, unsaturated polyamide, polycarboxylic acid, polycarboxylic acid (partial) amine salt, polycarboxylic acid ammonium salt and polycarboxyl. Acid alkylamine salts, polysiloxanes, long-chain polyaminoamide phosphates, hydroxyl-containing polycarboxylic acid esters or modified substances thereof, amides formed by reaction of poly (lower alkyleneimines) with polyesters having free carboxyl groups Water-soluble resins and water-soluble polymers, such as oily dispersing agents, (meth) acrylic acid-styrene copolymer, (meth) acrylic acid- (meth) acrylic acid ester copolymer, styrene-maleic acid copolymer, polyvinyl alcohol, polyvinylpyrrolidone Compound, polyester, modified polyacrylate, ethylene oxide / propylene oxide addition compound, phosphoric acid s A tere type etc. are used, These can be used individually or in mixture of 2 or more types.

The said pigment derivative is a compound which introduce | transduced the substituent into the organic pigment | dye. Such organic dyes also include light yellow aromatic polycyclic compounds such as naphthalenes and anthraquinones, which are not generally referred to as dyes. As a dye derivative, Japanese Patent Publication No. 63-305173, Japanese Patent Publication No. 57-15620, Japanese Patent Publication No. 59-40172, Japanese Patent Publication No. 63-17102, and Japanese Patent Publication What is described in -9469 etc. can be used, These can be used individually or in mixture of 2 or more types.

When hardening the coloring composition for color filters of this invention by light irradiation, such as an ultraviolet-ray, the monomer and oligomer which are transparent resin precursors can be mix | blended. These monomers and oligomers can be used individually or in mixture of 2 or more types.

Examples of the monomer and oligomer which are transparent resin precursors include methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and cyclohexyl ( Meta) acrylate, β-carboxyethyl (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexanedioldi (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, bisphenol A diglycidyl Etherdi (meth) acrylate, neopentyl glycol diglycidyl ether di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, ester arc Various acrylic esters and methacrylic esters, such as (meth) acrylic acid ester of methylolated melamine, epoxy (meth) acrylate, urethane acrylate, (meth) acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl ether, Ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N-vinylformamide, acrylonitrile and the like.

The transparent resin precursor can be used in an amount of 10 to 300 parts by weight, preferably 10 to 200 parts by weight with respect to 100 parts by weight of the colorant in the color composition for color filters.

When hardening the coloring composition for color filters of this invention by light irradiation, such as an ultraviolet-ray, a photoinitiator is added.

Examples of the photoinitiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane- Acetophenone type photoinitiators, such as 1-one, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2- dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoin, Benzoin type photoinitiators, such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyl dimethyl ketal, benzophenone, benzoyl benzoic acid, methyl benzoyl benzoate, 4-phenyl benzophenone, hydroxy benzophenone, and acrylated benzo Benzophenone system photoinitiators, such as phenone and 4-benzoyl-4'-methyldiphenyl sulfide, a thioxanthone, 2-chloro thioxanthone, 2-methyl thioxanthone, an isopropyl thioxanthone, 2, 4- Thioxanthone type photoinitiator, such as diisopropyl thioxanthone, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis (trichloro Methyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-tril) -4,6-bis (trichloro Methyl) -s-triazine, 2-piphenyl-4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (trichloromethyl) -6-styryl-s-triazine, 2- (naphtho-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxy-naphtho-1-yl) -4,6-bis (trichloro Rhomethyl) -s-triazine, 2,4-trichloromethyl- (piperonyl) -6-triazine, 2,4-trichloromethyl (4'-methoxystyryl) -6-triazine, etc. Triazine photoinitiators, borate photoinitiators, carbazole photoinitiators, imidazole photopolymerization initiators, and the like. A photoinitiator can be used in the quantity of 5-200 weight part, Preferably it is 10-150 weight part with respect to 100 weight part of coloring materials in the coloring composition for color filters.

The photopolymerization initiators may be used alone or in combination of two or more thereof.As a sensitizer, α-acyl oxime ester, acyl phosphine oxide, methylphenylglyoxylate, benzyl, 9,10-phenanthrene quinone, camphor quinone, ethyl Anthraquinone, 4,4'-diethylisophthalophenone, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 4,4'-diethylaminobenzophenone You may use a compound together. A sensitizer can be used in the quantity of 0.1-60 weight part with respect to 100 weight part of photoinitiators in the coloring composition for color filters.

The coloring composition for color filters of this invention can contain a storage stabilizer in order to stabilize the viscosity with time of a composition. Moreover, in order to improve adhesiveness with a transparent substrate, adhesive improving agents, such as a silane coupling agent, can also be contained.

As said storage stabilizer, For example, organic acids, such as quaternary ammonium chloride, such as benzyl trimethyl chloride and diethylhydroxyamine, lactic acid, and oxalic acid, its methyl ether, t-butyl pyrocatechol, tetraethylphosphine, tetraphenyl Organic phosphines, phosphites, such as phosphine, etc. are mentioned. A storage stabilizer can be used in the quantity of 0.1-10 weight part with respect to 100 weight part of coloring agents in the coloring composition for color filters.

Examples of the silane coupling agent include (meth) acryl such as vinyl silanes such as vinyl tris (β-methoxyethoxy) silane, vinyl ethoxy silane and vinyl trimethoxy silane, and γ-methacryloxypropyl trimethoxy silane. Silanes, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) methyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyl Epoxy silanes such as triethoxysilane, β- (3,4-epoxycyclohexyl) methyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, N -β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldie Oxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrie And thiosilanes such as aminosilanes such as oxysilane, γ-mercaptopropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane. The silane coupling agent can be used in an amount of 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on 100 parts by weight of the colorant in the coloring composition for color filters.

<Conductivity Adjuster>

In order to adjust the conductivity determined by the kind and ratio of a solvent to an appropriate range, the conductivity regulator is suitably added to the coloring composition for color filters of this invention as needed. The conductivity modifier is a kind of so-called surfactant having a hydrophobic group and a hydrophilic group in the molecule, and has a hydrophilic group and a low solubility in water, and when added to the coloring composition for color filters, the surface tension lowering ability is low. It is useful to have good wettability to the glass plate even though the surface tension lowering ability is low, and one capable of sufficiently inhibiting chargeability at an added amount in which defects in the coating film due to bubbling do not appear can be preferably used.

As such a conductivity modifier, dimethylpolysiloxane having a polyalkylene oxide unit can be preferably used. Examples of the polyalkylene oxide units include polyethylene oxide units and polypropylene oxide units, and dimethylpolysiloxane may have both polyethylene oxide units and polypropylene oxide units.

In addition, the bond form of the polyalkylene oxide unit with the dimethylpolysiloxane is a pendant type in which the polyalkylene oxide unit is bound in the repeating unit of the dimethylpolysiloxane, a terminal modified form bonded to the terminal of the dimethylpolysiloxane, or a straight chain alternately bonded to the dimethylpolysiloxane. May be any of the block copolymer type.

Dimethylpolysiloxanes with polyalkylene oxide units are described by Dow Corning Toray Co. It is commercially available from Ltd., and examples thereof include, but are not limited to, FZ-2110, FZ-2122, FZ-2130, FZ-2166, FZ-2191, FZ-2203, and FZ-2207.

The conductivity modifier may be used in an amount of preferably 0.01 to 10 parts by weight, and more preferably 0.05 to 5 parts by weight with respect to 100 parts by weight of the colorant in the color composition for color filters. When it is less than 0.01 weight part with respect to 100 weight part of coloring agents, there exists a tendency for the thickness uniformity of the edge part of the thin film formed in the board | substrate to deteriorate. Moreover, when more than 10 weight part with respect to 100 weight part of coloring materials, there exists a tendency of bubbling of a coating liquid.

It is also possible to add anionic, cationic, nonionic or amphoteric surfactants auxiliary to the conductivity modifier. Two or more types of surfactant may be mixed and used for it.

Examples of the anionic surfactants include polyoxyethylene alkyl ether sulfate, sodium dodecylbenzene sulfonate, alkali salts of styrene-acrylic acid copolymer, sodium alkylnaphthalin sulfonate, sodium alkyldiphenyl ether disulfonate and lauryl sulfate monoethanolamine And lauryl sulfate triethanolamine, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of the styrene-acrylic acid copolymer, polyoxyethylene alkyl ether phosphate ester, and the like.

As said cationic surfactant, alkyl quaternary ammonium salts and those ethylene oxide addition products are mentioned.

As said nonionic surfactant, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether phosphate ester, polyoxyethylene sorbitan monostearate, polyethylene glycol monolaurate Etc .; Amphoteric surfactants, such as alkylbetaine, such as alkyldimethylaminoacetic acid betaine, and alkyl imidazoline, and fluorine type and silicone type surfactant.

These auxiliary additives can be used in the ratio of 1-50 weight part with respect to 100 weight part of conductivity adjusters.

<Preparation of the coloring composition for color filters>

As for the coloring composition for color filters of this invention, various dispersions, such as three roll mills, two roll mills, a sand mill, a kneader, and an atortor, in a transparent resin and an organic solvent with a pigment dispersant, a photoinitiator, etc. as needed for a coloring agent. It can be prepared by finely dispersing by means of means. Moreover, the coloring composition for color filters containing two or more types of coloring agents can also be manufactured by mixing what disperse | distributed each coloring agent finely in transparent resin and the organic solvent separately.

The coloring composition for color filters of this invention can be prepared as a gravure offset printing ink, anhydrous offset printing ink, silk screen printing ink, a solvent developing type, or an alkali developing type coloring resist material.

The solvent developing type or alkali developing type colored resist material is obtained by dispersing a colorant in a composition containing a thermoplastic resin, a thermosetting resin, or a photosensitive resin, which is a transparent resin, and a monomer, a photopolymerization initiator, a surface regulator, and an organic solvent, as necessary.

The coloring composition for color filters of the present invention is coarse particles of 5 μm or more, preferably 1 μm or more of coarse particles, more preferably 0.5 μm or more of coarse particles and mixed dust by means of centrifugation, sintering filter, membrane filter, or the like. It is preferable to remove.

In order to maintain the thickness uniformity of the coating film and to reduce streaks, it is preferable that the color composition for color filters of the present invention has a low viscosity not only immediately after production but also after storage for a certain period of time. It is preferable that the viscosity of the coloring composition for color filters of this invention measured at the rotation speed of 20 rpm using the E-type viscosity meter at 25 degreeC is 20 mPa * s or less. When it exceeds 20 mPa · s, stable coating becomes difficult by the spin coating method or the die coating method, and it tends to be difficult to secure the coating film uniformity.

<Color filter>

Next, the manufacturing method of the color filter of this invention is demonstrated.

The color filter includes a filter segment on the substrate, and may include, for example, a black matrix and filter segments of red, green, and blue. The said filter segment is formed on a board | substrate by apply | coating the coloring composition of this invention by a spin coat method or the die coat method.

As a substrate of a color filter, glass plates, such as soda-lime glass, low alkali borosilicate glass, and alkali-free alumino borosilicate glass, which have high transmittance | permeability with visible light, and resin plates, such as polycarbonate, polymethyl methacrylate, polyethylene terephthalate, are used. Moreover, the transparent electrode which consists of indium oxide, a tin oxide, etc. may be formed in the glass plate or the resin plate surface for liquid crystal drive after panelization.

In developing, aqueous solutions, such as sodium carbonate and sodium hydroxide, are used as alkaline developing solution, Organic alkali, such as dimethylbenzylamine and triethanolamine, can also be used. A defoaming agent or a surfactant may be added to the developer.

As the developing treatment method, a shower developing method, a spray developing method, a dipping (immersion) developing method, a paddle (liquid pooling) developing method, or the like can be applied.

On the other hand, in order to improve the ultraviolet exposure sensitivity, the colored resist material is applied and dried, followed by coating and drying a water-soluble or alkali-soluble resin such as polyvinyl alcohol or a water-soluble acrylic resin to prevent polymerization inhibition by oxygen. After formation, ultraviolet light exposure can be performed.

Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to a following example, unless the summary is exceeded.

In the Examples and Comparative Examples, "parts" and "%" mean "parts by weight" and "% by weight", respectively.

First, preparation of the acrylic resin solution used by the Example and the comparative example is demonstrated. The molecular weight of resin is the weight average molecular weight of polystyrene conversion measured by GPC (gel permeation chromatography).

<Preparation of acrylic resin solution>

800 parts of cyclohexanone was put into the reaction container, it heated at 100 degreeC, injecting nitrogen gas into a container, and the mixture of the following monomer and the thermal polymerization initiator was dripped over 1 hour at the same temperature, and polymerization reaction was performed.

2-hydroxyethyl methacrylate 60.0 parts

Methacrylic acid 60.0 parts

Methyl methacrylate 65.0 parts

Butyl methacrylate 65.0 parts

10.0 parts of azobisisobutylonitrile

After dripping was made to react at 100 degreeC again for 3 hours, what melt | dissolved 2.0 parts of azobisisobutyronitrile in 50 parts of cyclohexanone was added, and reaction was continued at 100 degreeC for 1 hour, and the acrylic resin solution was obtained. The weight average molecular weight of the acrylic resin was about 40000.

After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and based on the measured value, cyclohexanone was added so that the nonvolatile content was 20% in the previously synthesized resin solution. It was added to prepare an acrylic resin solution. The solubility parameter of this resin was 10.8 (cal / cm <3>) ^1/2 .

Example  One

After the mixture of the following composition was stirred and mixed uniformly, it was made to disperse | distribute with a sand mill using glass beads of diameter 1mm for 5 hours, and it filtered with the filter of 5 micrometers, and produced the red pigment dispersion.

Red pigment:

Diketopyrrolopyrrole pigment (C.I. Pigment Red 254) 9.95parts

(Siba Specialty Chemicals, Inc. "Igapo Red B-CF")

Anthraquinone Pigment (C.I. Pigment Red 177) 1.58parts

(Shiba Specialty Chemicals, Inc. "Chromoftal Red A2B")

Anthraquinone Pigment (C.I. Pigment Yellow 199) 0.47part

("Chromophthal Yellow GT-AD" manufactured by Ciba Specialty Chemicals)

12.0 total red pigments

2.40 parts of pigment dispersant ("Solsper's 20000" manufactured by Geneca)

Acrylic resin solution 25.6 parts

60.0 parts cyclohexanone

Subsequently, the mixture of the following composition was stirred and mixed so that it might become uniform, and it filtered with the 1 micrometer filter and obtained the coloring composition for color filters prepared as a red resist material.

38.0 parts of red pigment dispersion

Acrylic resin solution 14.0 parts

Trimethylolpropanetriacrylate3.98part

(Shin-Nakamura Chemical Co., Ltd. "NK ester ATMPT")

1.65 parts of photoinitiators

(Shiba Specialty Chemical Co., Ltd. "Igacure 907")

Sensitizer ("EAB-F" manufactured by Hodogaya Chemical Co., Ltd.) 0.15 parts

Cyclohexanol acetate 40.0 parts

2.22 parts cyclohexanone

The coloring composition composition (weight part which made the coloring composition whole quantity 100), the ratio with respect to the solvent and the pigment 100, is shown in Table 1A.

Examples 2-11 and Comparative Examples 1-3

The pigment and organic solvent corresponding to the color of each Example and each comparative example shown to Table 1A-1E were selected from the following. Moreover, the ratio (the weight part, the solvent powder, and the pigment powder which made the coloring composition whole quantity 100) the ratio which showed the compounding quantity of a pigment, a pigment dispersant, an acrylic resin, a monomer, a photoinitiator, a sensitizer, an organic solvent, and a conductivity regulator in Table 1A-1E. The coloring composition prepared as each resist material was obtained by the method similar to Example 1 except having changed to the ratio with respect to 100).

Red pigment:

Diketopyrrolopyrrole pigment (C.I. Pigment Red 254) 3.78parts

("Igapo Red B-CF" manufactured by Ciba Specialty Chemical)

Anthraquinone Pigment (C.I. Pigment Red 177) 0.60part

(Shiba Specialty Chemical Co., Ltd. "Chromophthal Red A2B")

0.18 parts of anthraquinone pigment (C.I.Pigment Yellow 199)

("Chromoptal Yellow GT-AD" manufactured by Ciba Specialty Chemical)

                                                       4.56 total

Green pigment:

Copper halide phthalocyanine pigment

(C.I. Pigment Green 36) 2.90

(Toyo Ink Co., Ltd. "Lionol Green 6YK")

1.55 parts of nickel azo complex pigment (C.I.Pigment Yellow 150)

(Manufactured by LANXESS "E4GN")

                                                       4.45 copies in total

Blue pigment:

ε-type copper phthalocyanine pigment (C.I. Pigment Blue 15: 6) 4.50 parts

("Heliozen Blue L-6700F" manufactured by BASF)

[Table 1a]

[Table 1b]

[Table 1c]

TABLE 1d

TABLE 1e

The boiling point, conductivity and SP value of the organic solvents A to C are shown in Table 2.

[Table 2]

Each resist material obtained in Examples 1 to 11 and Comparative Examples 1 to 3 was applied on a 360 mm × 465 mm glass substrate with an average thickness of 2.0 μm using a spin coat method and a die coat method, respectively. And the obtained coating board | substrate was pre-baked at 70 degreeC for 20 minutes, and the dry coating film was obtained.

For the die coat method, the coated substrate was set within 10 minutes after the coating liquid was set and the substrate coated with the slit for 2 hours in a state where the coating liquid was attached to the slit (= coated substrate after standing) was produced. Compared.

Hereinafter, the description method of an evaluation item and a result is described. Determination in each evaluation result was set as a good level, (triangle | delta) is a level which does not interfere with use, and x is a level which is unpreferable to use.

<Both spin coat and die coat>

The die coat was evaluated for the initial coated substrate.

Thickness uniformity (end): The thickness was measured at 3 mm intervals from the center of the short side edge of the coating film to 3 cm toward the substrate center. Using the maximum thickness as Tmax, the minimum thickness as Tmin, and the average thickness as Tavg, the degree of elevation of the outer periphery of the coating film was calculated as thickness uniformity by the following formula (1).

Thickness Uniformity [%] = ((Tmax-Tmin) / (Tavg × 2)) × 100 (1)

Thickness uniformity (other than the end): The thickness was measured at 2 cm intervals from the center of the substrate of the coated substrate to 26 cm in the diagonal direction. Thickness uniformity (other than an edge part) was computed by said Formula (1) by the method similar to the above.

It is preferable that any thickness uniformity [%] is 5% or less, and it can be judged that uniformity is sufficiently high that it is 2% or less.

<Die coat method only>

"Vertical streaked stain": After standing, the coated substrate was visually evaluated through white transmitted light. (Circle) and the case where a streak stain was observed were made (circle) and the case where a streak stain was severe was made into the case where no stripe stain was observed.

"Horizontal stripes unevenness": Visual evaluation was performed on the initial coated substrate through white transmitted light. (Circle) and the case where a streak stain was observed were made (circle) and the case where a streak stain was severe was made into the case where no stripe stain was observed.

<Regardless of coating method>

(Cancellation of the property)

The initial coating substrate of the die coat was evaluated in accordance with JIS-K5600. When no tack was seen at all, (circle) and a case where a tack was seen a little, (triangle | delta) and the case where a tack was remarkably set were made into x.

(Conductivity of coating solution)

The conductivity of the coating solution was measured using a Conductivity Meter Model 645 and 627 manufactured by Scientifica.

(Stability over time)

The initial viscosity of the coating liquid at 25 ° C. and the viscosity after lapse of one week at 40 ° C. were measured at an rpm of 20 rpm using an E-type viscometer (TUE-20L manufactured by TOKI SANGYO).

Each evaluation result is shown to Tables 3A-3B.

TABLE 3a

TABLE 3b

In Examples 1-10, favorable result was obtained about all the items evaluated by selection of the kind and weight ratio of the preferable organic solvent A, the organic solvent B, and the organic solvent C. In Example 11, since the organic solvent A did not contain cyclohexanol acetate, slight vertical streaks were observed.

In Comparative Example 1, since the organic solvent A was not contained, the coating liquid showed high conductivity, and as a result, it thickened with time. In addition, drying and solidification occurred in the slit portion of the die coat, resulting in vertical streaks.

In Comparative Examples 2 and 3, since the weight ratio of the organic solvent A was too high, the conductivity was relatively low, resulting in slight horizontal stripe staining, and no tack property was resolved.

Since the coloring composition for color filters of this invention contains the organic solvent A and the organic solvent B which have a boiling point and conductivity which respectively exist in a specific range in the specific ratio, they are excellent in stability over time. Moreover, the coating film which apply | coated this coloring composition has the thickness nonuniformity, the stripe | stain stain, and the remainder of tack property being reduced, and thickness is uniform and it has the outstanding performance.

Since the color filter of this invention is equipped with the filter segment formed from the coloring composition for color filters mentioned above, it has favorable quality.

When the coloring composition for color filters of this invention is used for manufacture of a color filter by a spin coat system and a die coat system, the formed filter segment has remarkably good quality.

Claims (12)

An organic solvent A containing a transparent resin, a coloring agent and an organic solvent, the boiling point at 760 mmHg of the organic solvent being 160 ° C or more and less than 250 ° C, and a conductivity at 25 ° C of 0.001 nS / cm or more and less than 0.8 nS / cm. , An organic solvent B having a boiling point of 760 mmHg at a boiling point of 100 ° C. or more and less than 160 ° C., and a conductivity at 25 ° C. of 0.8 nS / cm or more and less than 50 nS / cm, wherein the organic solvent A contains cyclohexanol acetate, In addition, based on the total amount of the organic solvent is contained in a ratio of 5% by weight or more and less than 60% by weight, the organic solvent B is characterized in that it is contained in a ratio of 40% to 95% by weight based on the total amount of the organic solvent. The coloring composition for color filters. The solubility parameter δ _SA of the organic solvent A is 8.5 (cal / cm 3) ^1/2 or more and 13.5 (cal / cm 3) ^1/2 or less, and the solubility parameter δ _p of the transparent resin and the organic solvent. The difference in the solubility parameter (delta) _SA of A is within 2.5 (cal / cm <3>) ^1/2 , The coloring composition for color filters characterized by the above-mentioned. The coloring composition for color filters according to claim 1 or 2, wherein the transparent resin is a methacrylic copolymer having methacrylic acid and 2-hydroxyethyl methacrylic acid as a copolymerization component. The group according to claim 1, wherein the organic solvent A consists of cyclohexanol acetate, or a group consisting of diethylene glycol diethyl ether, ethyl 3-ethoxypropionate, propylene glycol diacetate, carbitol acetate, and butyl carbitol acetate The coloring composition for color filters which consists of a mixture of at least 1 sort (s) of organic solvent A 'and cyclohexanol acetate selected from the group. The coloring composition for color filters according to claim 1, wherein the organic solvent B is at least one organic solvent selected from the group consisting of cyclohexanone, propylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether. The coloring composition for color filters of Claim 1 containing dimethylpolysiloxane which has a polyalkylene oxide unit as a conductivity adjuster. The coloring composition for color filters according to claim 4, wherein a difference between the solubility parameter δ _p of the transparent resin and the solubility parameter δ _SA of the organic solvent A is within 2.5 (cal / cm 3) ^1/2 . The coloring composition for color filters according to claim 4, wherein the transparent resin is a methacrylic copolymer having methacrylic acid and 2-hydroxyethyl methacrylic acid as a copolymerization component. The coloring composition for color filters according to claim 4, wherein the organic solvent B is at least one organic solvent selected from the group consisting of cyclohexanone, propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether. The coloring composition for color filters of Claim 4 containing dimethylpolysiloxane which has a polyalkylene oxide unit as a conductivity adjuster. The filter segment formed using the coloring composition for color filters of Claim 1 or 4 is provided. The color filter characterized by the above-mentioned. The color filter coloring composition of Claim 1 or 4 is apply | coated on a board | substrate by a spin coat method or a die coat method, and a filter segment is formed, The manufacturing method of the color filter characterized by the above-mentioned.