JP4835210B2 - Coloring composition for color filter, color filter, and method for producing color filter - Google Patents

Description

  The present invention relates to a colored composition used for a color filter used in a color liquid crystal display device, a color image pickup tube element, and the like, a color filter using the colored composition, and a method for producing the color filter.

Color filters that make up liquid crystal displays (LCDs), color image pickup tube elements (CCDs), etc. are coated and dried on a transparent substrate with a coating solution (color filter coloring composition), and the coating thickness is about 1 to 3 μm. Manufactured by forming a film. As the coating method, there are a spin coating method, a die coating method, and the like, which are appropriately used according to the characteristics.
The spin coating method is widely used for forming a thin film on a relatively small-sized substrate. While rotating the transparent substrate at a constant rotational speed, the coating solution is dropped onto the central portion of the transparent substrate and centrifugal force is applied. Is a coating method in which a coating film having a desired film thickness is formed on the surface of the transparent substrate by extending the coating solution thinly and controlling the number of revolutions and the rotation time of the transparent substrate suitable for the coating solution. However, due to the principle of extending the coating film thinly by utilizing the centrifugal force due to rotation, there is a drawback that the coating film thickness at the rotation center portion and the peripheral portion of the transparent substrate becomes too thick compared to the intermediate portion.

In Patent Document 1, a composition containing 50% by weight or more of a solvent having a boiling point or vapor pressure within a specific range is described as a composition for a spin coating method having excellent coating surface smoothness.
When the size of the substrate is large, a method of rotating the substrate such as the spin coating method has a large load on the apparatus, and thus the die coating method is adopted.

  The die coating method is a coating method in which a coating liquid having a desired thickness is formed on the surface of a transparent substrate while discharging a coating liquid from the slit and moving the slit. However, due to its mechanism, it is easy to generate stripes in the direction perpendicular to the direction of movement of the slit, and the coating liquid is exposed to the outside air at the slit opening to dry and solidify, thereby forming an aggregate, and thereby the direction of application of the coating. As a result, the agglomerates are mixed into the coated material, resulting in a coating film defect. Furthermore, there is a problem that the outer peripheral portion of the coating film rises and the film thickness becomes thicker than the central portion of the substrate.

Attempts described in the following patent documents have been made to solve the problem of non-uniformity of the coating film in such a die coating method.
Patent Documents 2 and 3 disclose a method in which a coating liquid is prevented from being dried and solidified by containing a high-boiling solvent, and no aggregate is generated.
In Patent Document 4, the tackiness is increased by containing a solvent having a high boiling point, and the evaporation rate is specified as an invention for the defect that the tackiness (tackiness) of the coating film is not eliminated even after the coating film drying process. A method of solvent composition within the range is described.

JP-A-6-3521 JP 2003-55566 A JP 2004-346218 A Japanese Patent Laid-Open No. 10-104825

Due to the coating method such as the spin coating method and the die coating method and the properties of the coating liquid used therefor, the following defects are observed.
Unevenness of film thickness: Insufficient film thickness uniformity, “film thickness uniformity (edge) = film thickness uniformity of end face” and “film thickness uniformity (other than edge) = substrate It is classified into “uniformity from the center to the front of the end face”.
Straight stripe: “Striped unevenness that occurs in the direction perpendicular to the direction of slit movement in the horizontal stripe unevenness = die coating method” and “Strip shape in the direction of slit movement caused by the aggregate of slit openings in the vertical stripe unevenness = die coating method” Are classified into two categories.
Tacking property: “Tacking property = a defect in which the tackiness of the coating is not eliminated even after a coating drying process such as natural drying, drying by heating or drying under reduced pressure.”
Stability over time of coating solution: Viscosity after aging changes with respect to initial viscosity.

The problem is how to reduce these drawbacks. However, as described in the above-mentioned patent documents, the method of simply containing a high-boiling solvent, the method of making the solvent composition with an evaporation rate within a specific range, Not enough to eliminate the drawbacks.
An object of the present invention is to provide a coloring composition for a color filter in which defects observed in a coating film of a coating by a spin coating method or a die coating method are reduced, and a color filter including a filter segment formed using the same. And

The present invention includes a transparent resin, and a dye, a color filter coloring composition containing an organic solvent, wherein the organic solvent A and the organic solvent B organic solvent has the following characteristics, organic solvent A is cyclo It contains hexanol acetate and is contained in the range of 5% by weight to 47.62% by weight based on the total amount of the organic solvent , and the organic solvent B is in the range of 40% by weight to less than 95% by weight based on the total amount of the organic solvent. It is a coloring composition for color filters characterized by containing.
Organic solvent A: An organic solvent having a boiling point at 760 mmHg of 160 ° C. or more and less than 250 ° C. and an electric conductivity at 25 ° C. of 0.001 nS / cm or more and less than 0.8 nS / cm.
Organic solvent B: an organic solvent having a boiling point at 760 mmHg of 100 ° C. or more and less than 160 ° C. and an electric conductivity at 25 ° C. of 0.8 nS / cm or more and less than 50 nS / cm.

In the present invention, 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 A A coloring composition for a color filter, wherein the difference from the solubility parameter δ _SA is 2.5 (cal / cm ³ ) ^{1/2 or} less.

  The present invention is the coloring composition for a color filter, wherein the transparent resin is a methacrylic copolymer containing methacrylic acid and 2-hydroxyethyl methacrylic acid as a copolymerization component.

In the present invention, the organic solvent A is cyclohexanol acetate alone or at least one selected from the group consisting of diethylene glycol diethyl ether, ethyl 3-ethoxypropionate, propylene glycol diacetate, carbitol acetate, and butyl carbitol acetate. A coloring composition for a color filter, which is a mixture with hexanol acetate.

  The present invention is the color filter coloring composition, wherein the organic solvent B is at least one selected from the group consisting of cyclohexanone, propylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether.

  The present invention is a color filter coloring composition characterized by containing dimethylpolysiloxane having a polyalkylene oxide unit as a conductivity adjusting agent.

  The present invention is a color filter comprising a filter segment formed using a coloring composition for a color filter.

  The present invention is a method for producing a color filter, wherein a filter segment is formed by applying a colored composition for a color filter onto a substrate by a spin coating method or a die coating method.

  The coloring composition for a color filter of the present invention is excellent in stability over time because the organic solvents A and B having a specific range of boiling point and conductivity are blended in a specific ratio. Moreover, the coating film which apply | coated this coloring composition has the film thickness nonuniformity, a nonuniformity, and the tackiness residue, the film thickness is uniform, and has the outstanding performance.

  The color filter of the present invention has a good quality because it includes a filter segment formed from the above-described coloring composition for a color filter.

  When the color composition for color filter of the present invention is used in the production of a color filter by a spin coat method and a die coat method, the formed filter segment has a remarkably good quality.

First, the coloring composition for a color filter of the present invention will be specifically described.
The coloring composition for a color filter of the present invention is a coloring composition for a color filter containing a transparent resin, a dye, and an organic solvent, and the organic solvent includes an organic solvent A and an organic solvent B having the following characteristics. The organic solvent A contains cyclohexanol acetate and is contained in the range of 5% by weight to 47.62% by weight based on the total amount of the organic solvent , and the organic solvent B is 40% by weight or more based on the total amount of the organic solvent. A coloring composition for a color filter, which is contained in a range of less than 95% by weight.
Organic solvent A: An organic solvent having a boiling point at 760 mmHg of 160 ° C. or more and less than 250 ° C. and an electric conductivity at 25 ° C. of 0.001 nS / cm or more and less than 0.8 nS / cm.
Organic solvent B: an organic solvent having a boiling point at 760 mmHg of 100 ° C. or more and less than 160 ° C. and an electric conductivity at 25 ° C. of 0.8 nS / cm or more and less than 50 nS / cm.

<Organic solvent>
The characteristic of the organic solvent used in the present invention is that the boiling point, conductivity, and weight blending ratio of the organic solvent A and the organic solvent B constituting the organic solvent are in specific ranges, respectively. By the combination of the organic solvent A and the organic solvent B within this specific range, it is possible to constitute a color filter coloring composition in which the drawbacks of the conventional coated products described in the problem are reduced.
The boiling point of the organic solvent is related to the drying property of the color filter coloring composition (= coating liquid, hereinafter referred to as “coating liquid” where appropriate). The coating liquid is easily dried and solidified products are easily generated. If the solvent having a high boiling point is too much, tackiness (adhesion of the coating film surface) is not eliminated even after the coating film drying process. As a result, dust tends to adhere to the surface of the coating film, and the mask may be contaminated in the proximity exposure machine. If a large amount of the organic solvent remains in the coating film, the coating film may be peeled off from the glass substrate, particularly the glass substrate having the SiO ₂ film on the surface, during development.

  Except for a special case where a strong ionic material is added as a material constituting the coating solution, the conductivity of the solvent contained in the coating solution correlates with the conductivity of the coating solution. If the conductivity of the coating solution is too high, the affinity with moisture in the outside air will increase, and the stability over time will decrease due to the incorporation of moisture, etc. Conversely, if the conductivity of the coating solution is too low, the chargeability of the solution will increase. When the discharge property of the coating liquid from the slit becomes unstable, uneven coating (lateral unevenness) is likely to occur. In addition, the charging of the coating liquid makes it easier for the liquid to collect at the outer peripheral portion of the coating film, and the swell of the outer peripheral portion of the coating film increases.

Moreover, it is more preferable that the solubility parameter of the organic solvent A is in a specific range.
The solubility parameter (= SP value) of the organic solvent is a value obtained from the physical quantity (e.g., heat of evaporation) of the organic solvent, and values described in various documents can be used.
The organic solvent A preferably has high solubility in the transparent resin used in the color filter coloring composition. The SP value 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. Further, it is preferred that a difference between the solubility parameter [delta] _SA solubility parameter of the transparent resin [delta] _P and an organic solvent A is 2.5 (cal / cm ³⁾ is within ^1/2.
If the solubility parameter of the organic solvent and the solubility parameter of the transparent resin are close, the solubility of the resin increases and the coating solution can be prevented from solidifying, but on the other hand, it tends to lack stability over time. However, the stability over time can be compensated by using the organic solvent A having the characteristic of low electrical conductivity.
In order to make the characteristics described above appropriate, it is necessary that the weight blending ratios of the organic solvent A and the organic solvent B in the organic solvent used in the color filter coloring composition of the present invention are in appropriate ranges.

The organic solvent A contained in the coloring composition for a color filter of the present invention has a boiling point at 760 mmHg of 160 ° C. or more and less than 250 ° C. and an electric conductivity at 25 ° C. of 0.001 nS / cm or more and less than 0.8 nS / cm. The conductivity in the present invention is measured using Conductivity Meter Models 645 and 627 manufactured by Scientifica.
Examples of the organic solvent A include cyclohexanol acetate, diethylene glycol diethyl ether, ethyl 3-ethoxypropionate, propylene glycol diacetate, carbitol acetate, and butyl carbitol acetate. In particular, cyclohexanol acetate is preferably used because its boiling point is not too high, its conductivity is low, and the solubility parameter is at a more appropriate value. Therefore, it is preferable to use cyclohexanol acetate alone or a mixture of cyclohexanol acetate and another solvent as a more preferable solvent composition. When using a plurality of organic solvents, the solubility parameter can be generally obtained by adding the solubility parameter of each organic solvent to the value obtained by multiplying each weight fraction in the total amount of the organic solvent.

  The content of the organic solvent A in the color filter coloring composition is 5% by weight or more and less than 60% by weight based on the total amount of the organic solvent. 10 wt% or more and 50 wt% or less is more preferable. If it is out of the range of 5% by weight or more and less than 60% by weight, even if it is mixed with the organic solvent B, all of the defects of the conventional coated product described in the problem cannot be sufficiently improved.

  The organic solvent B contained in the coloring composition for a color filter of the present invention has a boiling point at 760 mmHg of 100 ° C. or more and less than 160 ° C. and an electric conductivity at 25 ° C. of 0.8 nS / cm or more and less than 50 nS / cm. Examples thereof include cyclohexanone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether and the like.

  The content of the organic solvent B in the color filter coloring composition is 40% by weight or more and less than 95% by weight based on the total amount of the organic solvent. More preferably, it is 40 wt% or more and 80 wt% or less. If it is out of the range of 40% by weight or more and less than 95% by weight, even if it is mixed with the organic solvent A, all of the defects of the conventional coated product described in the problem cannot be sufficiently improved.

  In the present invention, an organic solvent C can be used in addition to the organic solvents A and B. The organic solvent C can be added in a range not exceeding 40% by weight based on the total amount of the organic solvent. Examples thereof include isoamyl acetate and tripropylene glycol methyl ether. These can be used alone or in combination.

<Transparent resin>
The transparent resin used in the coloring composition for a color filter of the present invention is a resin having a transmittance of preferably 80% or more, more preferably 95% or more in the entire wavelength region of 400 to 700 nm in the visible light region.
The transparent resin includes a thermoplastic resin, a thermosetting resin, a photosensitive resin, and the like, and these can be used alone or in combination of two or more.

  The resin solubility parameter in the present invention is a value calculated by the Fedors method. When two or more kinds of resins are used in combination, the solubility parameter value of the mixed resin calculated from the following formula is used as the resin solubility parameter. It is a parameter.

_{δ P = a 1 δ P1 +} a 2 δ P2 + a 3 δ P3 + ··· + a n δ Pn
δ _P : Solubility parameter of 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 mixed resin a ₂ : Weight fraction of resin 2 in mixed resin a ₃ : Weight fraction of resin 3 in mixed resin
・
・
a _n : weight fraction of resin n in mixed resin

  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 pigment in the color filter coloring composition.

  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, and polyester resin. , Acrylic resins, alkyd resins, polystyrene, polyamide resins, rubber resins, cyclized rubber resins, celluloses, polyethylene, polybutadiene, polyimide resins, and the like.

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

  Examples of the photosensitive resin include (meth) acrylic compounds having a reactive substituent such as an isocyanate group, an aldehyde group, and an epoxy group on a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group, or an amino group, A resin obtained by reacting an acid and introducing a photocrosslinkable group such as a (meth) acryloyl group or a styryl group into the linear polymer is used. Further, a linear polymer containing an acid anhydride such as a styrene-maleic anhydride copolymer or an α-olefin-maleic anhydride copolymer is converted into a (meth) acrylic compound having a hydroxyl group such as hydroxyalkyl (meth) acrylate. Half-esterified products are also used.

  When patterning the color filter coloring composition by photolithography, it is preferable to use an alkali-soluble resin capable of alkali development. As the alkali-soluble resin, a methacrylic copolymer containing methacrylic acid and 2-hydroxyethyl methacrylic acid as a copolymerization component is preferable from the viewpoint of patterning characteristics, pigment dispersibility, solvent resistance, and the like.

<Dye>
As the coloring matter used in the coloring composition for a color filter of the present invention, organic or inorganic pigments can be used alone or in admixture of two or more. Among the pigments, pigments having high color developability and high heat resistance, particularly pigments having high heat decomposition resistance are preferred, and organic pigments are usually used.
Below, the specific example of the organic pigment which can be preferably used for the coloring composition for color filters of this invention is shown with a color index number.
Red pigmented compositions for forming red filter segments include, for example, CI Pigment Red 7, 9, 14, 41, 48: 1, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2. 81: 3, 97, 122, 123, 146, 149, 168, 177, 178, 180, 184, 185, 187, 192, 200, 202, 208, 210, 215, 216, 217, 220, 223, 224 Red pigments such as 226, 227, 228, 240, 246, 254, 255, 264, and 272 can be used. A yellow pigment and an orange pigment can be used in combination with the red coloring composition.

  Examples of the yellow coloring composition for forming the yellow filter segment include CI 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, 16 It can be used yellow pigments such 168,169,170,171,172,173,174,175,176,177,179,180,181,182,185,187,188,193,194,199.

For example, an orange pigment such as CI Pigment orange 36, 43, 51, 55, 59, 61 can be used as the orange coloring composition for forming the orange filter segment.
As the green coloring composition for forming the green filter segment, for example, a green pigment such as CI Pigment Green 7, 10, 36, 37 can be used. A yellow pigment can be used in combination with the green coloring composition.
Examples of blue coloring compositions for forming blue filter segments include CI Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 60, 64, etc. Blue pigments can be used. Purple pigments such as CI Pigment Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, and 50 can be used in combination with the blue coloring composition.
For example, CI Pigment Blue 15: 1, 15: 2, 15: 4, 15: 3, 15: 6, 16, 81 or the like is used as a cyan coloring composition for forming a cyan filter segment. Can do.

  For the magenta coloring composition for forming the magenta color filter segment, purple pigments and red pigments such as C.I. Pigment Violet 1, 19, C.I. Pigment Red 144, 146, 177, 169, 81 can be used. A yellow pigment can be used in combination with the magenta colored composition.

Inorganic pigments include barium sulfate, zinc white, lead sulfate, yellow lead, zinc yellow, red bean (red iron (III) oxide), cadmium red, ultramarine blue, bitumen, chromium oxide green, cobalt green, amber, titanium black, synthetic Examples thereof include metal oxide powders such as iron black, titanium oxide, and iron tetroxide, metal sulfide powders, and metal powders. Inorganic pigments are used in combination with organic pigments in order to ensure good coatability, sensitivity, developability and the like while maintaining a balance between saturation and lightness.
Moreover, the coloring composition of this invention can be made to contain a dye within the range which does not reduce heat resistance for color matching.

  When the dye is dispersed in the transparent resin and the organic solvent, a dispersion aid such as a surfactant, a resin-type pigment dispersant, and a dye derivative can be appropriately used as the pigment dispersant. Since the dispersion aid is excellent in pigment dispersion and has a great effect of preventing re-aggregation of the pigment after dispersion, a coloring composition obtained by dispersing the pigment in a transparent resin and an organic solvent using the dispersion aid is used. If so, a color filter excellent in transparency can be obtained. The pigment dispersant can be used in an amount of 0.1 to 40 parts by weight, preferably 0.1 to 30 parts by weight with respect to 100 parts by weight of the dye in the coloring composition.

  Surfactant as a dispersion aid used for pigment dispersion is polyoxyethylene alkyl ether sulfate, sodium dodecylbenzenesulfonate, alkali salt of styrene-acrylic acid copolymer, sodium alkylnaphthalenesulfonate, sodium alkyldiphenyletherdisulfonate , Lauryl sulfate monoethanolamine, lauryl sulfate triethanolamine, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene alkyl ether phosphate Anionic surfactants such as: polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl Nonionic surfactants such as ethers, polyoxyethylene alkyl ether phosphates, polyoxyethylene sorbitan monostearate, polyethylene glycol monolaurate; chaotic surfactants such as alkyl quaternary ammonium salts and their ethylene oxide adducts Agents: Examples include amphoteric surfactants such as alkylbetaines such as alkyldimethylaminoacetic acid betaine, alkylimidazolines, and fluorine or silicone surfactants.

  Resin-type pigment dispersants are resins that have a pigment-affinity part that has the property of adsorbing to the pigment, and a part that is compatible with the transparent resin. It works to do. Specific examples of resin-type pigment dispersants include polycarboxylic acid esters such as polyurethane and polyacrylate, unsaturated polyamides, polycarboxylic acids, polycarboxylic acid (partial) amine salts, polycarboxylic acid ammonium salts, and polycarboxylic acid alkylamines. Salts, polysiloxanes, long-chain polyaminoamide phosphates, hydroxyl group-containing polycarboxylic acid esters, their modified products, amides formed by the reaction of poly (lower alkyleneimines) with polyesters having free carboxyl groups, and the like Water-based dispersants such as oily dispersants such as salts, (meth) acrylic acid-styrene copolymers, (meth) acrylic acid- (meth) acrylic acid ester copolymers, styrene-maleic acid copolymers, polyvinyl alcohol, polyvinylpyrrolidone Resin, water-soluble polymer, polyester Modified polyacrylate, ethylene oxide / propylene oxide addition compound, phosphate ester-based and the like are used, they can be used alone or in admixture of two or more.

  A pigment derivative is a compound in which a substituent is introduced into an organic pigment. Such organic dyes also include light yellow aromatic polycyclic compounds such as naphthalene and anthraquinone which are not generally called dyes. Examples of the dye derivatives are described in JP-A-63-305173, JP-B-57-15620, JP-B-59-40172, JP-B-63-17102, JP-B-5-9469, and the like. These can be used alone or in combination of two or more.

When the colored composition for a color filter of the present invention is cured by irradiation with light such as ultraviolet rays, monomers and oligomers that are precursors of a transparent resin can be used. These can be used alone or in admixture of two or more.
Monomers and oligomers that are precursors of transparent resins include methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, β -Carboxyethyl (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexanediol di (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 ether di (me Acrylate), neopentyl glycol diglycidyl ether di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, ester acrylate, (meth) acrylic acid ester of methylolated melamine, epoxy ( Various acrylic esters and methacrylic esters such as (meth) acrylate and urethane acrylate, (meth) acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl ether, ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth) acrylamide, N-hydroxy Examples include methyl (meth) acrylamide, N-vinylformamide, acrylonitrile and the like.
The precursor of the transparent resin 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 pigment in the color filter coloring composition.

When the coloring composition for a color filter of the present invention is cured by irradiation with light such as ultraviolet rays, a photopolymerization initiator is added.
Examples of the photopolymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- Acetophenone photopolymerization initiators such as hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl Benzoin photopolymerization initiators such as ether and benzyldimethyl ketal, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzene Benzophenone-based photopolymerization initiators such as zoyl-4′-methyldiphenyl sulfide, thioxanthone-based light such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone Polymerization initiator, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloro) Methyl) -s-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2-pienyl-4,6-bis (trichloromethyl) -s-triazine, 2,4 -Bis (trichloromethyl) -6-styryl-s-triazine, 2- (naphth-1-yl) -4,6-bis (to Chloromethyl) -s-triazine, 2- (4-methoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-trichloromethyl- (piperonyl) -6-triazine , 2,4-trichloromethyl (4′-methoxystyryl) -6-triazine and other triazine photopolymerization initiators, borate photopolymerization initiators, carbazole photopolymerization initiators, imidazole photopolymerization initiators and the like are used. It is done. A photoinitiator can be used in the amount of 5-200 weight part with respect to 100 weight part of pigment | dye in the coloring composition for color filters, Preferably it is 10-150 weight part.

  The above photopolymerization initiators can be used alone or in combination of two or more. As the sensitizer, α-acyloxime ester, acylphosphine oxide, methylphenylglyoxylate, benzyl, 9,10- Phenanthrenequinone, camphorquinone, ethylanthraquinone, 4,4'-diethylisophthalophenone, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 4,4'-diethylaminobenzophenone These compounds can also be used in combination. 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 a color filter of the present invention can contain a storage stabilizer in order to stabilize the viscosity with time of the composition. Moreover, in order to improve adhesiveness with a transparent substrate, adhesion improving agents, such as a silane coupling agent, can also be contained.
Examples of storage stabilizers include quaternary ammonium chlorides such as benzyltrimethyl chloride and diethylhydroxyamine, organic acids such as lactic acid and oxalic acid, and organic acids such as methyl ether, t-butylpyrocatechol, tetraethylphosphine, and tetraphenylphosphine. Examples thereof include phosphine and phosphite. The storage stabilizer can be used in an amount of 0.1 to 10 parts by weight with respect to 100 parts by weight of the dye in the color filter coloring composition.

  Examples of the silane coupling agent include vinyl silanes such as vinyltris (β-methoxyethoxy) silane, vinylethoxysilane, and vinyltrimethoxysilane, (meth) acrylsilanes such as γ-methacryloxypropyltrimethoxysilane, β- (3 , 4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) methyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ) Epoxysilanes such as methyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β ( Aminoethyl) γ-aminopro Lutriethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N Examples include aminosilanes such as -phenyl-γ-aminopropyltriethoxysilane, thiosilanes such as 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, with respect to 100 parts by weight of the dye in the color filter coloring composition.

<Conductivity adjusting agent>
The color filter coloring composition of the present invention is appropriately added with a conductivity adjusting agent as necessary as a means for adjusting the conductivity determined by the type and ratio of the solvent to an appropriate range.
As a conductivity adjusting agent, it is a kind of so-called surfactant having a hydrophobic group and a hydrophilic group in the molecule, has a hydrophilic group but has a low solubility in water, and when added to a color filter coloring composition, It has the feature that its surface tension lowering ability is low, and it is useful to have good wettability to the glass plate despite its low surface tension lowering ability, and the added amount that does not cause coating film defects due to foaming In this case, those that can sufficiently suppress the chargeability can be preferably used.
As the conductivity adjusting agent, dimethylpolysiloxane having a polyalkylene oxide unit can be preferably used. Examples of the polyalkylene oxide unit include a polyethylene oxide unit and a polypropylene oxide unit, and dimethylpolysiloxane may have both a polyethylene oxide unit and a polypropylene oxide unit.

In addition, the bonding form of the polyalkylene oxide unit with dimethylpolysiloxane includes a pendant type in which the polyalkylene oxide unit is bonded in the repeating unit of dimethylpolysiloxane, a terminal-modified type in which the end of dimethylpolysiloxane is bonded, and dimethylpolysiloxane. Any of linear block copolymer types in which they are alternately and repeatedly bonded may be used.
Dimethylpolysiloxane having a polyalkylene oxide unit is commercially available from Toray Dow Corning Co., Ltd., for example, FZ-2110, FZ-2122, FZ-2130, FZ-2166, FZ-2191, FZ-2203, FZ -2207, but is not limited thereto.

  The conductivity adjusting agent can be used in an amount of preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight with respect to 100 parts by weight of the dye in the color filter coloring composition. When the amount is less than 0.01 part by weight with respect to 100 parts by weight of the dye, the film thickness uniformity at the end of the thin film formed on the substrate tends to deteriorate. Further, when the amount is more than 10 parts by weight with respect to 100 parts by weight of the dye, the coating liquid tends to foam.

An anionic, cationic, nonionic or amphoteric surfactant can be supplementarily added to the conductivity adjusting agent. Two or more kinds of surfactants may be mixed and used.
Examples of the anionic surfactant include polyoxyethylene alkyl ether sulfate, sodium dodecylbenzenesulfonate, alkali salt of styrene-acrylic acid copolymer, sodium alkylnaphthalenesulfonate, sodium alkyldiphenyletherdisulfonate, monoethanolamine laurylsulfate , Lauryl sulfate triethanolamine, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene alkyl ether phosphate, and the like.

Examples of chaotic surfactants include alkyl quaternary ammonium salts and their ethylene oxide adducts.
Nonionic surfactants include polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene alkyl ether phosphate, polyoxyethylene sorbitan monostearate, polyethylene glycol monolaurate, etc. And amphoteric surfactants such as alkylbetaines such as alkyldimethylaminoacetic acid betaine and alkylimidazolines, and fluorine-based and silicone-based surfactants.

<Coloring composition for color filter>
The coloring composition for a color filter of the present invention comprises a three-roll mill, a two-roll mill, a sand mill, a kneader, and an attritor in a transparent resin and an organic solvent together with the pigment dispersant and the photopolymerization initiator as necessary. It can be produced by finely dispersing using various dispersing means such as. Moreover, the coloring composition for color filters containing 2 or more types of pigment | dyes can also mix and manufacture what disperse | distributed each pigment | dye separately in transparent resin and the organic solvent separately.

  The coloring composition for color filter of the present invention can be prepared as gravure offset printing ink, waterless offset printing ink, silk screen printing ink, solvent developing type or alkali developing type colored resist material.

  The solvent development type or alkali development type colored resist material comprises a thermoplastic resin, a thermosetting resin, or a photosensitive resin, which is a transparent resin, and, if necessary, a monomer, a photopolymerization initiator, a surface conditioner, and an organic solvent. A pigment is dispersed in the composition to be contained.

  The colored composition for a color filter of the present invention is a coarse particle having a size of 5 μm or more, preferably a coarse particle having a size of 1 μm or more, more preferably a coarse particle having a size of 0.5 μm or more. It is preferable to remove the mixed dust.

  In order to maintain the film thickness uniformity of the coating film and reduce the unevenness, it is preferable that the coloring composition for color filter of the present invention has a low viscosity not only immediately after production but also after storage for a certain period. The colored composition for a color filter of the present invention preferably has a viscosity of 20 mPa · s or less measured at 25 ° C. using an E-type viscometer at a rotation speed of 20 rpm. If it exceeds 20 mPa · s, stable coating becomes difficult with the spin coating method or die coating method, and the uniformity of the coating film tends to be difficult to ensure.

<Color filter>
Next, a method for producing the color filter of the present invention will be described.
The color filter includes a filter segment on a substrate, and can include, for example, a black matrix and red, green, and blue filter segments. The filter segment is formed on the substrate by applying the coloring composition of the present invention by spin coating or die coating.

  Color filter substrates include glass plates such as soda-lime glass, low alkali borosilicate glass, and non-alkali aluminoborosilicate glass that have a high transmittance for visible light, and resins such as polycarbonate, polymethyl methacrylate, and polyethylene terephthalate. A plate is used. In addition, a transparent electrode made of indium oxide, tin oxide, or the like may be formed on the surface of the glass plate or the resin plate in order to drive the liquid crystal after forming the panel.

In development, an aqueous solution such as sodium carbonate or sodium hydroxide is used as an alkali developer, and an organic alkali such as dimethylbenzylamine or triethanolamine can also be used. Moreover, an antifoamer and surfactant can also be added to a developing solution.
As a development processing method, a shower development method, a spray development method, a dip (immersion) development method, a paddle (liquid accumulation) development method, or the like can be applied.
In order to increase the UV exposure sensitivity, the colored resist material is applied and dried, and then a water-soluble or alkali-soluble resin such as polyvinyl alcohol or water-soluble acrylic resin is applied and dried to form a film that prevents polymerization inhibition by oxygen. Then, ultraviolet exposure can be performed.

Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to the following examples unless it exceeds the gist.
In the examples and comparative examples, “parts” and “%” mean “parts by weight” and “% by weight”, respectively.
First, preparation of acrylic resin solutions used in Examples and Comparative Examples will be described. The molecular weight of the resin is a weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography).

(Preparation of acrylic resin solution)
A reaction vessel was charged with 800 parts of cyclohexanone, heated to 100 ° C. while injecting nitrogen gas into the vessel, and a mixture of the following monomer and thermal polymerization initiator was added dropwise at the same temperature over 1 hour to carry out a polymerization reaction.
2-hydroxyethyl methacrylic acid 60.0 parts
Methacrylic acid 60.0 parts
Methyl methacrylate 65.0 parts
Butyl methacrylate 65.0 parts
Azobisisobutyronitrile 10.0 parts After the addition, the mixture was further reacted at 100 ° C. for 3 hours, and then 2.0 parts of azobisisobutyronitrile dissolved in 50 parts of cyclohexanone was added. The reaction was continued for 1 hour to obtain an acrylic resin solution. The weight average molecular weight of the acrylic resin was about 40,000.
After cooling to room temperature, about 2 g of the resin solution was sampled and heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and cyclohexanone was added to the previously synthesized resin solution so that the nonvolatile content was 20%. An acrylic resin solution was prepared. The solubility parameter of this resin was 10.8 (cal / cm ³ ) ^1/2 .

[Example 1]
A mixture having the following composition was uniformly stirred and mixed, then dispersed with a sand mill for 5 hours using glass beads having a diameter of 1 mm, and then filtered with a 5 μm filter to prepare a red pigment dispersion.
Red pigment: 9.95 parts diketopyrrolopyrrole pigment (CI Pigment Red 254)
("Irga Four Red B-CF" manufactured by Ciba Geigy)
Anthraquinone pigment (CI Pigment Red 177) 1.58 parts
(Ciba Geigy “Chromophthal Red A2B”)
Anthraquinone pigment (CI Pigment Yellow 199) 0.47 parts
(Ciba Geigy's “Chromoval Yellow GT-AD”)
12.0 parts in total Pigment dispersant (“Solsperse 20000” manufactured by Zeneca) 2.40 parts Acrylic resin solution 25.6 parts Cyclohexanone 60.0 parts

Next, the mixture having the following composition was stirred and mixed to be uniform, and then filtered through a 1 μm filter to obtain a colored composition for a color filter prepared as a red resist material. Table 1 shows the composition of the colored composition (parts by weight with respect to 100 parts by weight of the total amount of the colored composition, solvent, and pigment content).
Red pigment dispersion 38.0 parts Acrylic resin solution 14.0 parts Trimethylolpropane triacrylate 3.98 parts ("NK ester ATMPT" manufactured by Shin-Nakamura Chemical Co., Ltd.)
Photopolymerization initiator (“Irgacure 907” manufactured by Ciba Geigy) 1.65 parts Sensitizer (“EAB-F” manufactured by Hodogaya Chemical Co., Ltd.) 0.15 parts Cyclohexanol acetate 40.0 parts Cyclohexanone 2.22 parts

[Examples 2 to 10 and Comparative Examples 1 to 3]
The pigments and organic solvents corresponding to the colors of Examples and Comparative Examples shown in Table 1 were selected from the following. Further, the proportions of pigments, pigment dispersants, acrylic resins, monomers, photopolymerization initiators, sensitizers, organic solvents, and conductivity modifiers shown in Table 1 (parts by weight with the total amount of the colored composition being 100) A colored composition prepared as each resist material was obtained in the same manner as in Example 1 except that the ratio was changed to the ratio of the solvent content and the pigment content of 100.

Pigment for red: 3.78 parts of diketopyrrolopyrrole pigment (CI Pigment Red 254) ("Irga Four Red B-CF" manufactured by Ciba Geigy)
Anthraquinone pigment (CI Pigment Red 177) 0.60 part (Ciba Geigy "Chromophthal Red A2B")
Anthraquinone pigment (CI Pigment Yellow 199) 0.18 parts (Ciba Geigy "Chromophthal Yellow GT-AD")
4.56 parts in total Green pigment: Halogenated copper phthalocyanine pigment (CI Pigment Green 36) 2.90 parts
("Rionol Green 6YK" manufactured by Toyo Ink Co., Ltd.)
Nickel azo complex pigment (CI Pigment Yellow 150) 1.55 parts
(“E4GN” manufactured by LANXESS) 4.45 parts in total Blue pigment: ε-type copper phthalocyanine pigment (CI Pigment Blue 15: 6) 4.50 parts
(BASF "Heliogen Blue L-6700F")

Table 2 shows data on the boiling points, conductivity, and SP of the organic solvents A to C.

About each resist material obtained in Examples 1-10 and Comparative Examples 1-3, the average film thickness is 2.0 μm on a 360 mm × 465 mm size glass substrate using a spin coat type and die coat type coating apparatus. Each of the coated substrates thus obtained was prebaked at 70 ° C. for 20 minutes to obtain a dried coating film.
For the die coating method, the substrate coated with the coating solution set within 10 minutes (= initial coated substrate) and the substrate coated with the coating solution attached to the slit for 2 hours (= coating after standing) Substrate) was created and compared.
The evaluation items and how to express the results are described below. In the evaluation in each evaluation result, ◯ is a good level, Δ is a level that does not interfere with use, and x is a level that is not preferable for use.

<Both spin coat and die coat>
For the die coat, the initial coated substrate was evaluated.
Film thickness uniformity (edge part): The film thickness was measured every 3 mm from the center of the short side of the coated film to 3 cm in the direction of the substrate center. The maximum film thickness was T _max , the minimum film thickness was T _min , the average film thickness was T _avg, and the degree of swell of the coating film outer periphery was calculated as film thickness uniformity by the following equation (1).
Film thickness uniformity [%] = ((T _max −T _min ) / (T _avg × 2)) × 100 (1)
Film thickness uniformity (other than edges): The film thickness was measured every 2 cm up to 26 cm in the diagonal direction from the center of the coated substrate. Similarly to the above, film thickness uniformity (other than the end portion) was calculated by the above equation (1).
Any film thickness uniformity [%] is preferably 5% or less, and if it is 2% or less, it can be judged that the uniformity is sufficiently high.
<Die coat method only>
“Vertical stripe unevenness”: The coated substrate after standing was evaluated by visual observation through white transmitted light. The case where no streak was observed was marked with ◯, the case where a slight streak was slightly observed was marked with Δ, and the case where streak was severe was marked with ×.
“Horizontal streak”: The initial coated substrate was visually evaluated through white transmitted light. The case where no streak was observed was marked with ◯, the case where a slight streak was slightly observed was marked with Δ, and the case where streak was severe was marked with ×.
<Not related to coating method>
(Resolve tackiness)
The initial coated substrate of the die coat was evaluated according to JIS-K5600. The case where no tack was found was rated as ◯, the case where slight tack was found was marked as Δ, and the case where marked tack was found was marked as x.
(Conductivity of coating solution)
The conductivity of the coating solution was measured using Conductivity Meter Model 645 and 627 manufactured by Scientifica.
(Stability over time)
The initial viscosity at 25 ° C. of the coating solution and the post-aging viscosity after standing for 1 week at 40 ° C. were measured at 20 rpm using an E-type viscometer (TUE-20L type manufactured by TOKI SANGYO).
The respective evaluation results are shown in Table 3.

About Examples 1-10, the favorable result was obtained about all the evaluated items by selection of the kind and weight ratio of the preferable organic solvent A, the organic solvent B, and the organic solvent C.
As for Comparative Example 1, since the organic solvent A was not contained, the coating liquid showed high conductivity, and as a result, the viscosity increased with time. In addition, drying and solidification occurred in the slit portion of the die coat, and vertical stripes were generated.
In Comparative Examples 2 and 3, since the weight ratio of the organic solvent A was too high, the electrical conductivity was lowered, a slight horizontal unevenness was generated, and the tackiness was not eliminated.

Claims (9)

A coloring composition for a color filter containing a transparent resin, a pigment, and an organic solvent,
The organic solvent includes an organic solvent A and an organic solvent B having the following characteristics:
The organic solvent A contains cyclohexanol acetate and is contained in the range of 5 wt% to 47.62 wt% based on the total amount of the organic solvent,
The organic solvent B is contained in a range of 40% by weight or more and less than 95% by weight based on the total amount of the organic solvent.
Organic solvent A: An organic solvent having a boiling point at 760 mmHg of 160 ° C. or more and less than 250 ° C. and an electric conductivity at 25 ° C. of 0.001 nS / cm or more and less than 0.8 nS / cm.
Organic solvent B: an organic solvent having a boiling point at 760 mmHg of 100 ° C. or more and less than 160 ° C. and an electric conductivity at 25 ° C. of 0.8 nS / cm or more and less than 50 nS / cm. 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, the solubility parameter δ _P of the transparent resin and the solubility parameter δ _SA of the organic solvent A The coloring composition for a color filter according to claim 1, wherein the difference is 2.5 (cal / cm ³ ) ^{1/2 or} less.   The colored composition for a color filter 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 organic solvent A is cyclohexanol acetate alone or at least one selected from the group consisting of diethylene glycol diethyl ether, ethyl 3-ethoxypropionate, propylene glycol diacetate, carbitol acetate, and butyl carbitol acetate and cyclohexanol acetate. The coloring composition for a color filter according to any one of claims 1 to 3, which is a mixture.   The colored composition for a color filter according to any one of claims 1 to 4, wherein the organic solvent B is at least one selected from the group consisting of cyclohexanone, propylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether. Furthermore, the coloring composition for color filters in any one of Claim 1 thru | or 5 containing a resin-type pigment dispersant. The colored composition for a color filter according to any one of claims 1 to 6, comprising dimethylpolysiloxane having a polyalkylene oxide unit as a conductivity adjusting agent. Color filter characterized by comprising a filter segment formed using claims 1 to 7 for a color filter coloring composition according to any one. A method for producing a color filter, comprising: applying a coloring composition for a color filter according to any one of claims 1 to 7 on a substrate by a spin coating method or a die coating method to form a filter segment.