JP6543444B2 - Red colorant composition for color filter - Google Patents

Description

  The present invention relates to a red colorant composition for a color filter used to form a color filter of a color display device.

  A color filter used in a color liquid crystal display device or the like is formed by arranging fine bands (stripes) of two or more different hues in parallel on the surface of a transparent substrate such as glass, or fine pixels having a constant height and width. It consists of arranged ones in an array. The pixel size is a fine size of several tens to several hundreds of μm, and furthermore, the colors are arranged in order in a predetermined order for each hue.

The color liquid crystal display device colors white light from the backlight through the color filter as described above, and displays a color image on the screen. Therefore, high transparency is required as the basic performance of color filters. Therefore, conventionally, it has been manufactured by using a so-called dyeing method or the like in which a dye excellent in color characteristics is dispersed in a resin in a molecular state and dyed. However, in recent years, with the diversification of applications, when it has become necessary to improve the reliability such as heat resistance and light resistance, organic pigments have come to be used instead of dyes having limitations in their performance. In addition, various methods such as a printing method, an inkjet method, and a photolithography method have been proposed as a method for producing a color filter.
In particular, in applications such as television monitors, color filters having pixels that enable high brightness and high contrast leading to high definition of a general image are required. It is supposed to be.

The above-mentioned brightness and contrast performance largely depend on the type of pigment dispersed in each color pixel of the color filter, and in particular, pigment red 254 and pigment red 177 are frequently used.
For example, Patent Document 1 proposes a system in which an orange pigment is used in combination with the pigment red 254 and the pigment red 177 of the main red pigment.
Patent Document 2 proposes a system using pigment red 176 to compensate for the contrast ratio of pigment red 254 and the brightness of pigment red 177.
However, in recent years, the quality required for the pixel of a television monitor is becoming increasingly high, and it is difficult to realize the required performance depending on the coloring composition for color filter having only a pigment as a coloring agent. In particular, in order to achieve high brightness, it is proposed to use a pigment and a dye in combination in a colorant composition for color filters.
Patent Document 3 proposes a system in which pigment red 254 or pigment red 177 is used as a pigment and a modified product such as acid red 289 or acid red 87 is used as a dye, but the modification process of the dye is complicated. They are not practical because they require labor and cost.
Moreover, in the colorant composition for color filters, when the pigment and the dye are used in combination, the temporal stability of the colorant composition for color filters tends to be inadequate, and the post-baking step in the preparation of the color filter There was a tendency for the brightness to decrease before and after.

Unexamined-Japanese-Patent No. 2010-223987 JP, 2009-237462, A JP, 2012-194521, A

  An object of the present invention is to provide a red colorant composition for color filters which has high brightness which can be used for color filters of display devices such as a television monitor and which has a small change in brightness even after post-baking treatment. .

  As a result of intensive studies to solve the above problems, the present inventors have found that pigments, pigment dispersion aids having an acid group, dyes, pigment dispersants, resins, compounds having a phosphoric acid group or salts thereof, and organic compounds The inventors have found that a red colorant composition for color filters having high brightness which can be used for color filters mainly composed of a solvent and having a small change in brightness can be obtained even by post-baking treatment, thereby completing the present invention. It came to

That is, the present invention
(1) A red colorant composition for a color filter mainly composed of a pigment, a pigment dispersion aid having an acid group, a dye, a pigment dispersant, a resin, a compound having a phosphoric acid group or a salt thereof, and an organic solvent. And the pigment has a diketopyrrolopyrrole skeleton, and the dye contains C.I. I. Acid Red 52, C.I. I. Acid Red 87, C.I. I. Acid Red 92, C.I. I. Acid Red 289, and C.I. I. A red colorant composition for a color filter, which is at least one selected from the group consisting of Acid Red 388.
(2) The red colorant composition for a color filter according to (1), wherein the acid value of the compound having a phosphoric acid group or a salt thereof is 10 to 300 mg KOH / g.
(3) The color filter according to (1) or (2), wherein the content of the compound having a phosphoric acid group or a salt thereof is 10 to 1000 parts by mass with respect to 100 parts by mass of the dye. Red colorant composition.
(4) The red colorant composition for a color filter according to any one of (1) to (3), wherein the pigment is a micronized pigment.
(5) The red colorant for color filter according to any one of (1) to (4), wherein the pigment dispersion aid having an acid group is a pigment dispersion aid having a sulfonic acid group. Composition.
In the present specification, “acid value” is obtained by dissolving or dispersing a sample with propylene glycol monomethyl ether, titrating with ethanol solution of potassium hydroxide with phenolphthalein as an indicator at 25 ° C. It is a value calculated by the following equation with a point having a pink color as an end point.
Acid value (mg KOH / g) = 56.1 x V x C / m
V: Titrate (ml),
C: Concentration of titrant (mol / l),
m: Weight of nonvolatile content of sample (g).

  According to the present invention, it is possible to obtain a red colorant composition for a color filter which is excellent in luminance and in which a change in luminance is small even by post-baking treatment.

As described above, when the pigment and the dye are used in combination in the red colorant composition for color filter, the temporal stability of the colorant composition for color filter tends to be insufficient, and the post in the preparation of the color filter Before and after the baking process, the luminance tended to decrease.
This tendency is considered by the following mechanism. That is, in the component forming the coating film of the color filter, the dye molecules have a relatively low molecular weight, and hence the dye molecules heated in the post-baking treatment are susceptible to thermal movement. In addition, since the dye molecules have a highly polar group such as a sulfonate, thermally moved dye molecules become easy to assemble due to the interaction between the highly polar groups. As a result, in the color filter coating film after post-baking treatment, an area containing an assembly of dye molecules and an area containing a relatively small amount of dye molecules are generated. When back light is applied to the post-baked color filter, low brightness is observed by the light transmitted through the region where the dye is relatively small in the color filter coating film.
According to the present invention, it is considered by the following mechanism that the change in luminance can be suppressed also by the post-baking treatment. That is, by introducing a substance containing a phosphoric acid group or a salt thereof into a colorant composition for a color filter, even if the dye molecule is thermally moved, the highly polar group possessed by the dye molecule is obtained by the phosphoric acid group or a salt thereof. Since the interaction between the groups is inhibited, the dye molecules are uniformly present in the color filter coating even after the post-baking treatment, and hence the change in luminance is small before and after the post-baking treatment.

  Hereinafter, the red colorant composition for a color filter of the present invention will be specifically described for each component thereof.

The present invention relates to a red colorant composition for a color filter of a display device such as a television monitor, and the red colorant composition for the color filter may be a composition that is not a resist, or a resist composition. It may be.
In any case, the red colorant composition for a color filter of a display device such as a television monitor of the present invention is a composition used for a color filter of a display device such as a television monitor, and the effect of the present invention is thereby Thus, it is possible to provide a red colorant composition for a color filter which has a high brightness and a small change in brightness even by post-baking treatment.

(Pigment)
The red colorant composition for color filters of the present invention uses a pigment having a diketopyrrolopyrrole skeleton as a pigment. As a specific example, C.I. I. Pigment red 254, brominated C.I. I. Pigment red 254, C.I. I. Pigment red 255, C.I. I. Pigment red 264, C.I. I. Pigment red 272, C.I. I. Pigment orange 71, C.I. I. Pigment orange 73, or C.I. I. Although a pigment such as pigment orange 81 can be mentioned, it is not limited to these.
Examples of pigments having a diketopyrrolopyrrole skeleton include C.I. I. Pigment Red 254 or its bromide is preferred. In particular, C.I. I. When pigment red 254 is used, the thickness of the film for obtaining the necessary lightness is thin, and the color characteristics (x, y, Y) become good.
The amount of the pigment having a diketopyrrolopyrrole skeleton in the present invention is preferably 5 to 80% by mass, more preferably 20 to 50% by mass fraction with respect to the total solid content of the red colorant composition of the present invention. It is mass%.
In order to impart high brightness and contrast to the red colorant composition for a color filter of the present invention, it is preferable to use a microparticulated color pigment. By performing the micronization treatment, the primary particle diameter of the color pigment can be made finer and uniform.
As the above-mentioned micronization treatment, for example, untreated color pigments, water-soluble inorganic salts (sodium chloride, barium chloride, potassium chloride, etc., preferably sodium chloride, the average particle size of the water-soluble inorganic salt used) Is preferably 50 μm or less), and a mixture containing a water-soluble dispersion medium (alkoxy alcohols, glycols, ethers, etc.) which does not substantially dissolve the water-soluble inorganic salt, a kneader, roll mill, ball mill , Attritor, Sand mill, Trimix (trade name) manufactured by Inoue Seisakusho Co., Ltd., which is a planetary mixer described in JP-A-2006-192385, manufactured by Asada Iron Works Co., Ltd., which is a continuous single-screw kneader Of the water-soluble inorganic salt and the water-soluble dispersion medium after kneading with a kneading apparatus such as Miracle KCK. Was carried out, it is preferable to perform the atomization treatment.

(Pigment dispersion aid having an acid group)
As a pigment dispersion aid having an acid group used in the red colorant composition for color filter of the present invention, the basic skeleton having the same or similar molecular structure as the pigment has an acid group for enhancing the affinity to an organic solvent. The one introduced is preferred. In such a pigment dispersion aid, the pigment is dispersed by the adsorption of a portion of the basic skeleton on the pigment surface and the increase in the affinity of the acid groups with the organic solvent and the pigment dispersant in the process of making the pigment into fine particles and dispersion. It has the effect of improving the time-lapse dispersion and stability with time after dispersion. In addition, those in which the pigment dispersion aid itself is dissolved or dispersed in the form of fine particles in an organic solvent are more preferable because they can be adsorbed over a wider range of the pigment surface.
Above all, good results can be obtained by using a pigment dispersion aid or the like having a sulfonic acid group as an acid group.
In the red colorant composition for a color filter of the present invention, the amount of use of the pigment dispersion aid having an acid group is 0.5 to 30 parts by mass with respect to 100 parts by mass of the pigment. When the content of the pigment dispersion aid having an acid group is smaller than 0.5 parts by mass, the pigment dispersion effect is reduced. On the other hand, when the content exceeds 30 parts by mass, the pigment dispersion effect is not further improved.

The pigment dispersion aid having the above acid group is
(1) When using a pigment which is micronized in the absence of a pigment dispersion aid having an acid group, the pigment is dispersed with an acid group with respect to 100 parts by mass of the color pigment when the micronized pigment is dispersed The adjuvant is used in an amount of 0.5 to 30 parts by mass, preferably 3 to 15 parts by mass.
(2) When using a pigment which is micronized in the presence of a pigment dispersion assistant having an acid group, 0.5 to 30 mass of the pigment dispersion assistant is used with respect to 100 parts by mass of the pigment when the pigment is micronized 0 to 29.5 parts by mass, preferably 0 to 29.5 parts by mass of a pigment dispersion aid having an acid group with respect to 100 parts by mass of the pigment treated with 1 part, preferably 3 to 15 parts by mass, when dispersing the micronized pigment Use 12 parts by mass.
The total amount of the pigment dispersion aid having an acid group used at the time of micronization treatment and the pigment dispersion aid having an acid group at the time of pigment dispersion of the pigment subjected to the micronization treatment is 100 parts by mass of pigment The pigment dispersion assistant having an acid group is used in an amount of 0.5 to 30 parts by mass, preferably 3 to 15 parts by mass.
More specifically, the case of using a pigment dispersion aid having a sulfonic acid group as a pigment dispersion aid having an acid group will be described.
As a pigment, a red pigment C.I. I. In dispersing pigment red 254, as a pigment dispersion aid having a sulfonic acid group, C.I. I. Sulfone of pigment and / or dye having a diketopyrrolopyrrole skeleton having the same skeleton as that of pigment red 254 (sulfonate of CI pigment red 254, sulfonate of brominated CI pigment red 254, C Pigment Red 255, CI Pigment Red 264, CI Pigment Red 272, CI Pigment Orange 71, CI Pigment Orange 73 Sulfonates, CI sulfonates of CI Pigment Orange 81, etc.) and C.I. I. Pigment dispersion aids having at least one sulfonic acid group selected from the sulfonates of CI Pigment Red 2 are used, among which C.I. I. It is preferable to use a sulfonate of pigment red 2.

(dye)
As a dye used for the red coloring agent composition for color filters of this invention, a xanthene type acid dye is used. As the xanthene acid dyes, C.I. I. Acid Red 50, C.I. I. Acid Red 51, C.I. I. Acid Red 52, C.I. I. Acid Red 87, C.I. I. Acid Red 92, C.I. I. Acid Red 289, C.I. I. Acid Red 388, Acid Rhodamine G, C.I. I. Acid Violet 9, C.I. I. Acid Violet 9, C.I. I. It is preferable to use Acid Violet 30. Among them, C.I. I. Acid Red 52, C.I. I. Acid Red 87, C.I. I. Acid Red 92, C.I. I. Acid Red 289, or C.I. I. It is preferable to use acid red 388.

(Compound having a phosphoric acid group or a salt thereof)
Examples of the compound having a phosphoric acid group or a salt thereof for use in a color filter for red-colored composition of the present invention, if example embodiment DISPERBYK-111, DISPERBYK-102, ( manufactured by BYK Chemie) DISPERBYK-106, PLYSURF A212C, ply Surf A 215 C, Plysurf A 208 F, Plysurf A 208 N, Plysurf A 208 B, Plysurf A 219 B, Plysurf A 210 D, Plysurf AL, Plysurf AL 12 H (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) can be used.
Moreover, the polymer which copolymerized the polymeric compound which has a phosphoric acid group or its salt, and another polymeric compound can also be used. As the polymerizable compound having a phosphoric acid group or a salt thereof, light ester P-1M, light ester P-2M (manufactured by Kyoeisha Chemical Co., Ltd.), and the like can be used.
In the red colorant composition for a color filter of the present invention, the amount of the compound having a phosphoric acid group or a salt thereof is preferably 10 to 1000 parts by mass with respect to 100 parts by mass of the dye, and 50 to 500 parts by mass. It is more preferable that it is a part. When the amount of the compound having the phosphoric acid group or the salt thereof is less than 10 parts by mass or more than 1000 parts by mass with respect to 100 parts by mass of the dye, the temporal stability of the colorant composition for color filter In some cases, the brightness may be reduced before and after the post-baking step in the preparation of the color filter.
In the red colorant composition for color filters of the present invention, the acid value of the compound having a phosphoric acid group or a salt thereof is preferably 10 to 300 mg KOH / g, more preferably 30 to 250 mg KOH / g, Furthermore, it is preferable that it is 50-200 mgKOH / g. If the acid value of the compound having a phosphoric acid group or a salt thereof is smaller than 10 mg KOH / g, or larger than 300 mg KOH / g, the temporal stability of the colorant composition for color filter may be insufficient. In addition, the luminance may be reduced before and after the post-baking step in forming the color filter.

(Pigment dispersant)
As a pigment dispersant used for the red coloring agent composition for color filters of this invention, the pigment dispersant conventionally used in the color filter field | area can be used.
In the red colorant composition for a color filter of the present invention, the amount of the pigment dispersant used is preferably 1 to 100 parts by mass, more preferably 1 to 60 parts by mass with respect to 100 parts by mass of the color pigment. . When the content of the pigment dispersant is smaller than 1 part by mass, the pigment dispersion effect may be reduced. On the other hand, when the content exceeds 100 parts by mass, developability may be reduced.

Examples of the pigment dispersant include the following.
(1) Polyesters, polyamides and polyesteramides having an amino group and / or an imino group of a polyamine compound (for example, poly (lower) alkylene amine such as polyallylamine, polyvinylamine, polyethylenepolyimine, etc.) and a free carboxyl group A reaction product with at least one selected from the group consisting of
(2) Carbodiimide compound having at least one basic nitrogen-containing group and at least one side chain selected from the group consisting of polyester side chain, polyether side chain, and polyacryl side chain in the molecule .
(3) A reaction product of a low molecular weight amino compound such as poly (lower) alkyleneimine and methyliminobispropylamine with a polyester having a free carboxyl group.
(4) An alcohol such as methoxypolyethylene glycol, a polyester having one hydroxyl group such as caprolactone polyester, an isocyanate group having polyisocyanate group, a compound having two to three isocyanate group reactive functional groups, an isocyanate group reactivity A reaction product obtained by sequentially reacting an aliphatic or heterocyclic hydrocarbon compound having a functional group and a tertiary amino group.
(5) A reaction product obtained by reacting a polymer of acrylate having an alcoholic hydroxyl group with a polyisocyanate compound and a hydrocarbon compound having an amino group.
(6) A reaction product obtained by adding a polyether chain to a low molecular weight amino compound.
(7) A reaction product obtained by reacting a compound having an isocyanate group with a compound having an amino group.
(8) A reaction product obtained by reacting a polyepoxy compound with a linear polymer having a free carboxyl group and an organic amine compound having one secondary amino group.
(9) A reaction product of a polycarbonate compound having a functional group capable of reacting with an amino group at one end and a polyamine compound.
(10) selected from methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, stearyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, stearyl acrylate, benzyl acrylate or acrylic acid esters And at least one basic group-containing polymerizable monomer such as acrylamide, methacrylamide, N-methylolamide, vinylimidazole, vinylpyridine, a monomer having an amino group and a polycaprolactone skeleton, and styrene, a styrene derivative And copolymers with at least one other polymerizable monomer.
(11) An acrylic block copolymer or the like comprising a block having a basic group such as a tertiary amino group and a quaternary ammonium base and a block not having a basic functional group.
(12) A pigment dispersant obtained by subjecting a polycarbonate compound to a Michael addition reaction with polyallylamine.
(13) A carbodiimide type compound having at least one polybutadiene chain and at least one basic nitrogen-containing group.
(14) A carbodiimide type compound having at least one side chain each having an amide group in the molecule and at least one basic nitrogen-containing group.
(15) A polyurethane-based compound having a structural unit having an ethylene oxide chain and a propylene oxide chain, and having an amino group quaternized by a quaternizing agent.
(16) Obtained by reacting the isocyanate group of an isocyanate compound having an isocyanurate ring in the molecule with the active hydrogen group of a compound having an active hydrogen group in the molecule and a carbazole ring and / or an azobenzene skeleton. Compound, which is a carbazole ring relative to the total of an isocyanate group derived from an isocyanate compound having an isocyanurate ring in the molecule of the compound and a urethane bond and a urea bond generated by the reaction of the isocyanate group and an active hydrogen group. And the compound whose number of azobenzene skeletons is 15 to 85%.

  At present, the resist method is mainly used as a method of producing a color filter using a red colorant composition for color filters, and thereafter, a red colorant composition for color filters used by a method other than the resist method, It divides into the red coloring agent composition for color filters used for the resist method, and demonstrates the component etc. which are contained in each below.

[A. Red Colorant Composition for Color Filter Used Other Than Resist Method]
The case where the red colorant composition for a color filter of the present invention is not a resist composition will be described.
When the present invention is not a red colorant resist composition for color filter, the composition does not have active energy ray curability, and a pigment, a pigment dispersion aid having an acid group, a dye, a pigment dispersant, It is mainly composed of a resin, a compound having a phosphate group or a salt thereof, and an organic solvent.
As the color pigment, the pigment dispersion aid having an acid group, and the pigment dispersant, those described above are used.

(resin)
As a resin used for the red coloring agent composition for color filters of the present invention, a resin having a transmittance of 80% or more, preferably 95% or more can be used in the whole wavelength range of 400 to 700 nm in the visible light range. . These resins include thermosetting resins, thermoplastic resins, alkali-soluble resins and the like. These can be used individually or in mixture of 2 or more types.
Such resin is preferably 5 to 94% by mass, more preferably 20 to 50% by mass in the total amount of the resin to be used by mass fraction with respect to the total solid content of the red colorant composition for color filter It is a range.
As a thermosetting resin and a thermoplastic resin, for example, butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyurethane Resin, phenol resin, polyester resin, acrylic resin, alkyd resin, styrene resin, polyamide resin, rubber resin, cyclized rubber, epoxy resin, celluloses, polybutadiene, polyimide resin, benzoguanamine resin, melamine resin, urea resin, etc. Can be mentioned.
The alkali-soluble resin will be described in detail in the case of a red colorant resist composition for color filter described later.

(Organic solvent)
Specific examples of the organic solvent used for the red colorant composition for color filters of the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, Ether-based organic solvents such as diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether A Ether ester organic solvents such as phthalate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate; ketone organic solvents such as methyl isobutyl ketone, cyclohexanone, 2-heptanone, δ-butyrolactone; Methyl hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, 3-methyl-3-methoxybutyl propionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3 -Ester-based organic solvents such as methyl ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, n-amyl formate, etc .; Examples include alcohol solvents such as ethanol, isopropyl alcohol and butanol; and nitrogen-containing organic solvents such as N-methylpyrrolidone, N, N-dimethylformamide, and N, N-dimethylacetamide. These can be used individually or in mixture of 2 or more types.
The red colorant composition for a color filter of the present invention is mainly composed of a pigment, a pigment dispersion aid having an acid group, a dye, a pigment dispersant, a resin, a compound having a phosphoric acid group or a salt thereof, and an organic solvent. These components occupy 90 to 100% by mass in the red colorant composition for color filter.

(Additives that can be added as needed)
Various additives such as a thermal polymerization inhibitor, an ultraviolet light absorber, an antioxidant and the like can be appropriately used according to the method of producing the colorant composition for color filter.

(Method of producing red colorant composition for color filter of the present invention)
A method of producing a red colorant composition for a color filter which is not used in the resist method using the above materials will be described.

  C. pigment which has been microparticulated in the presence or absence of a pigment dispersion aid having an acid group (preferably a sulfonate of CI pigment red 2 etc.). I. Pigment red 254, a pigment dispersion aid having an acid group (preferably a sulfonate of CI pigment red 2 etc.), a pigment dispersant, a resin, a compound having a phosphoric acid group or a salt thereof, an organic solvent, if necessary A mixture of other additives is obtained. The obtained mixture is subjected to kneading and dispersing treatment using various dispersing machines such as a roll mill, a kneader, a high speed stirring device, a bead mill, a ball mill, a sand mill, an ultrasonic dispersing machine and a high pressure dispersing machine to obtain a red colorant for color filters. The composition is obtained.

In the above manufacturing method, when using a micronized pigment which has been micronized in the presence of a pigment dispersion aid having an acid group, the pigment dispersion aid having an acid group is not contained when dispersing the micronized pigment. Even manufacturing is possible.
In the above-mentioned production method, the resin, the phosphoric acid group or the compound having a salt thereof can be added before and / or after the kneading / dispersion treatment.

[B. Red Colorant Composition for Color Filter Used in Resist Method]
Next, the case where the red colorant composition for a color filter of the present invention is used as a colorant-dispersed resist composition for a color filter will be described.
When the present invention is a red colorant resist composition for a color filter, the composition is an active energy ray curable, alkali developable resist composition, and has a pigment, a dye, and a pigment having an acid group. It is mainly composed of a dispersion aid, a pigment dispersant, a resin, a compound having a phosphoric acid group or a salt thereof, and an organic solvent, and the resin includes an alkali soluble resin and a photopolymerizable compound.
The pigment, the pigment dispersion aid having an acid group, and the pigment dispersant are used as described above.

(Alkali-soluble resin as resin)
The alkali-soluble resin as a resin used in the red colorant resist composition for color filters of the present invention acts as a binder for red pigments and is used in the development processing step when producing a color filter It is not particularly limited as long as it is soluble in a developing solution, particularly preferably an alkaline developing solution, and conventional ones can be used. Among them, an alkali-soluble resin having a carboxyl group is preferable, and in particular, a copolymer of an ethylenically unsaturated monomer having one or more carboxyl groups and another copolymerizable ethylenically unsaturated monomer is more preferable. preferable.
Specifically, styrene, 2-hydroxyethyl acrylate, which can be copolymerized with an ethylenically unsaturated monomer having a carboxyl group such as acrylic acid and methacrylic acid, and an ethylenically unsaturated monomer having a carboxyl group -Hydroxyethyl methacrylate, allyl acrylate, allyl methacrylate, benzyl acrylate, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, glycerol monoacrylate, glycerol methacrylate, N-phenylmaleimide, polystyrene macromonomer, polymethyl methacrylate macromonomer, carboepoxy diacrylate etc. And copolymers with at least one ethylenically unsaturated monomer selected from the group of monomers and oligomers of
The acid value of the alkali-soluble resin in the present invention is preferably 50 to 300 mg KOH / g from the viewpoint of development characteristics.
The weight average molecular weight of the alkali-soluble resin in the present invention is usually preferably 1,000 to 100,000 from the viewpoint of development characteristics and solubility in organic solvents. In the present invention, the weight average molecular weight of the alkali-soluble resin is a weight average molecular weight in terms of polystyrene obtained based on GPC. In the present invention, Water 2690 (manufactured by Waters) is used as an apparatus, and PLgel 5μ MIXED-D (manufactured by Polymer Laboratories) is used as a column.
The amount of the alkali-soluble resin used in the present invention is 1 to 300 parts by mass, preferably 10 to 200 parts by mass, with respect to 100 parts by mass of the pigment to be used. In this case, if the amount of the alkali-soluble resin used is less than 1 part by mass, the development characteristics may be degraded. On the other hand, if it exceeds 300 parts by mass, the colorant concentration relatively decreases, and it may be difficult to achieve the target color concentration as a thin film.

(Photopolymerizable compound that forms a resin)
As a photopolymerizable compound which can form resin used for the red coloring agent resist composition for color filters of this invention, it is a monomer, an oligomer, etc. which have one or more photopolymerizable unsaturated bonds in a molecule | numerator. , The same one as described in the above-mentioned red colorant composition for color filter is used. The photopolymerizable unsaturated bond is an unsaturated bond that can be polymerized by the action of radicals or cations generated when the photopolymerization initiator described later is decomposed by active energy rays such as ultraviolet rays and electron beams. .
The photopolymerizable compounds capable of forming these resins can be used alone or in combination of two or more. In the present invention, the amount of the photopolymerizable compound used is preferably in the range of 3 to 50% by mass in terms of mass fraction with respect to the total solid content in the red colorant resist composition for a color filter.

(Photopolymerization initiator)
As a photoinitiator used for the red coloring agent resist composition for color filters of the display apparatus of this invention, a radical and a cation can be generate | occur | produced by irradiating active energy rays, such as an ultraviolet-ray and an electron beam. It is not particularly limited as long as it is a substance, for example, benzophenone, N, N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, benzyl, 2,2-diethoxyacetophenone, benzoin , Benzoin methyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, α-hydroxy isobutyl phenone, thioxanthone, 2-chlorothioxanthone, 1-hydroxy cyclohexyl phenyl ketone, t-butyl anthraquinone, 1-chloro anthraquinone, 2,3-di Loroanthraquinone, 3-chloro-2-methylanthraquinone, 2-ethylanthraquinone, 1,4-naphthoquinone, 1,2-benzoanthraquinone, 1,4-dimethylanthraquinone, 2-phenylanthraquinone, 2-methyl-1 [4-] Examples include (methylthio) phenyl] -2-morpholinopropan-1-one, and triazine-based photopolymerization initiators. These photoinitiators are used individually or in combination of 2 or more types.
In the present invention, the content of the photopolymerization initiator is preferably in the range of 1 to 20% by mass in mass fraction with respect to the total solid content in the red colorant resist composition for the color filter.

(Organic solvent)
As an organic solvent used for the red coloring agent resist composition for coloring agent color filters of this invention, the organic solvent conventionally used in the field | area of liquid crystal color filter resist can be used conveniently. Specifically, ester organic solvents having a boiling point of 100 to 220 ° C. under normal pressure (1.013 × 102 kPa), ether organic solvents, ether ester organic solvents, ketone organic solvents, aromatic hydrocarbon organic solvents And nitrogen-containing organic solvents. When the boiling point contains a large amount of organic solvent exceeding 220 ° C., the organic solvent does not evaporate sufficiently at the time of prebaking the coating film formed and remains in the dried coating film, and the heat resistance of the dried coating film There is a risk that the sex may decline. In addition, when a large amount of the organic solvent having a boiling point of less than 100 ° C. is contained, it becomes difficult to apply uniformly without unevenness, and there is a possibility that a coating film having excellent surface smoothness can not be obtained.
Specific examples of preferable solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether. Ether-based organic solvents such as ether, propylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether Ether ester organic solvents such as tate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate; ketone organic solvents such as methyl isobutyl ketone, cyclohexanone, 2-heptanone, δ-butyrolactone; methyl 2-hydroxypropionate, 2 -Ethyl ethyl hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, 3-methyl-3-methoxybutyl propionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, Ester-based organic solvents such as ethyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate and n-amyl formate; N-methylpyrrolidone, N, N-dimethylformamide, N, N-diester Nitrogen-containing organic solvents such as methylacetamide can be exemplified. These can be used individually or in mixture of 2 or more types.

  Among these organic solvents, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, cyclohexanone, in terms of solubility, dispersibility, coatability, etc. -Heptanone, ethyl 2-hydroxypropionate, 3-methyl-3-methoxybutyl propionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, n-amyl formate and the like are preferable, more preferably propylene glycol It is monomethyl ether acetate.

  These organic solvents are 50% by mass or more in the red colorant resist composition for color filters of the present invention from the viewpoint of solubility of the above-mentioned alkali-soluble resin, dispersibility of color pigments, coatability and the like. Preferably, 70% by mass or more is more preferable.

  The red colorant resist composition for a color filter of the present invention comprises a color pigment, a pigment dispersion aid having an acid group, a polymer pigment dispersant having a basic group, an alkali soluble resin, a photopolymerizable compound and a photopolymerization initiator. The composition is mainly composed of barium sulfate and an organic solvent, and these components occupy 90 to 100% by mass in the red colorant resist composition for color filter.

(Additives that can be added as needed)
In the red colorant resist composition for a color filter of the present invention, various additives such as a thermal polymerization inhibitor, an ultraviolet light absorber, an antioxidant and the like can be appropriately used as needed.

(Method of producing red colorant resist composition for color filter of the present invention)
A method for producing a red colorant resist composition for a color filter using the above materials will be described. The red colorant resist composition for color filter can be obtained by the following production method.

  C. pigment which has been microparticulated in the presence or absence of a pigment dispersion aid having an acid group (preferably a sulfonate of CI pigment red 2 etc.). I. Pigment red 254, a pigment dispersion aid having an acid group (preferably a sulfonate of CI pigment red 2 etc.), a pigment dispersant, a resin, a compound having a phosphoric acid group or a salt thereof, an organic solvent, if necessary A mixture of other additives is obtained. The obtained mixture is subjected to kneading and dispersing treatment using various dispersing machines such as a roll mill, a kneader, a high speed stirring device, a bead mill, a ball mill, a sand mill, an ultrasonic dispersing machine and a high pressure dispersing machine to obtain a red colorant for color filters. The composition is obtained. Furthermore, a photopolymerizable compound, a photopolymerization initiator, and optionally an alkali-soluble resin, an organic solvent and other additives are added to obtain a red colorant resist composition for a color filter of the present invention.

In the above manufacturing method, when using a micronized pigment which has been micronized in the presence of a pigment dispersion aid having an acid group, the pigment dispersion aid having an acid group is not contained when dispersing the micronized pigment. Even manufacturing is possible.
In the above-mentioned production method, the compound having a resin, a dye, a phosphoric acid group or a salt thereof can be added at the time of preparation of the colorant composition and / or after preparation of the colorant composition.
In addition, as a method for producing a color filter using the red colorant composition for color filters of the present invention, a method known as a constitution other than the colorant composition is adopted, including an apparatus necessary therefor. It can be manufactured.
The red colorant composition for a color filter having the specific composition of the present invention preferably has a chromaticity x of 0.6550 as the color characteristics (x, y, Y) among them. 0.322-0.330 are preferable and 0.322-0.324 of y are more preferable. Furthermore, the Y value which is the lightness is more preferably 12.2 or more, particularly 13.0 or more. Within this range, the coloring power and / or the brightness can be further improved.

  The present invention will be described in more detail by way of examples given below, but the present invention is not limited to these examples. In addition, "%" means "mass%" unless there is particular notice.

<Pigment dispersion aid>
(Pigment dispersion aid A: sulfonate of CI pigment red 2)
In a 100 ml Erlenmeyer flask, 30 ml of concentrated sulfuric acid was charged, and while stirring with a magnetic stirrer, C.I. I. 10 parts by mass of pigment red 2 was added, and stirred at room temperature for 30 minutes. A mixture of 50 parts by mass of water and 50 parts by mass of ice was placed in a 1 L beaker, the reaction product was poured into the ice water, and stirred with a magnetic stirrer for 30 minutes. The resultant was filtered and washed under reduced pressure, and the obtained solid was dried to obtain 12 parts by mass of pigment dispersion aid A.

<Particulated pigment>
(Particulated pigment A: trimix treated CI pigment red 254)
In a tank of Trimix TX-15 (trade name, manufactured by Inoue Seisakusho), C.I. I. Pigment Red 254, 800 parts by mass, 8000 parts by mass of sodium chloride having a particle diameter of 20 μm, and 1920 parts by mass of diethylene glycol were charged. It knead | mixed for 3 hours at 45 degreeC in the range used as 70% of rated current value 9.3A, and performed salt milling. Next, 1300 parts by mass of the obtained kneaded product was put into 3 liters of warm water and stirred for 1 hour while heating to 70 ° C. to form a slurry. After repeated filtration and washing with water, sodium chloride and diethylene glycol were removed, and then dried overnight at 40 ° C. to obtain 95 parts by mass of micronized pigment A.

(Pigment dispersant)
BYK-LPN 21116 (manufactured by Bick Chemie, acrylic polymer, amine value 29)

(Compound having a phosphoric acid group or a salt thereof)
BYK-111 (manufactured by Bick Chemie, phosphate group-containing copolymer, acid value 136, non volatile matter 95%)
BYK-102 (manufactured by Bick Chemie, phosphoric acid group-containing copolymer, acid value 102, non volatile matter 99%)
BYK-106 (Bick Chemie Co., Ltd., salt of phosphate group containing copolymer, acid value 145, non volatile matter 91%)
Phosphoric acid group-containing resin A (benzyl methacrylate / 2-methacryloyloxyethyl acid phosphate copolymer, acid value 50 mg KOH / g, weight average molecular weight: 10,000)
Phosphoric acid group-containing resin B (benzyl methacrylate / 2-methacryloyloxyethyl acid phosphate copolymer, acid value 200 mg KOH / g, weight average molecular weight: 10,000)
Phosphoric acid group-containing resin C (benzyl methacrylate / 2-methacryloyloxyethyl acid phosphate copolymer, acid value 20 mg KOH / g, weight average molecular weight: 10,000)
Phosphoric acid group-containing resin D (benzyl methacrylate / 2-methacryloyloxyethyl acid phosphate copolymer, acid value 300 mg KOH / g, weight average molecular weight: 10,000)

(resin)
Alkali-soluble resin A (benzyl methacrylate / methacrylic acid copolymer, acid value 120 mg KOH / g, mass average molecular weight: 25,000)

(Organic solvent)
PGME: Propylene glycol monomethyl ether PGMEA: Propylene glycol monomethyl ether acetate DAA: Diacetone alcohol

(Photopolymerizable compound)
DPEHA: dipentaerythritol hexaacrylate (photoinitiator)
Irgacure 369: 2-benzyl- (dimethylamino) -1- (4-morpholinophenyl) -1-butanone

<Red Colorant Composition for Color Filter>
The above-mentioned finely divided pigment, a pigment dispersion aid having an acid group, a pigment dispersant, an alkali soluble resin, a dye, a compound having a phosphoric acid group or a salt thereof, and an organic solvent having a composition of Table 1, zirconia of 0.2 mm diameter The mixture was kneaded for 6 hours with a paint conditioner using beads to obtain red colorant compositions 1 to 15 for color filters.

<Red Colorant Composition for Color Filter Used in Resist Methods of Examples 1 to 10 and Comparative Examples 1 to 5>
The red colorant resist materials for color filter were uniformly mixed so that the pigment ratio in Table 2 was obtained, and the red colorant composition for color filter used in the resist method of Examples 1 to 10 and Comparative Examples 1 to 5 was obtained. .

(Evaluation)
<Dispersion stability>
The red colorant compositions for color filters used in the resist methods of Examples 1 to 10 and Comparative Examples 1 to 5 were each taken in a glass bottle, sealed, and stored for 7 days at room temperature, and the state was evaluated according to the following evaluation criteria. did. The results are shown in Table 2.
○: Thickening and sedimentation were not observed at the same time.
:: Thickened or sedimented to some extent when lightly shaken.
X: Thickened or sedimented to such an extent that it does not return even if shaken vigorously is observed.

<Evaluation of color characteristics and luminance maintenance factor of red colorant composition for color filter used in resist method>
The red coloring agent composition for color filters used for the resist method of Examples 1-10 and Comparative Examples 1-5 was apply | coated on the glass substrate using the spin coater.
Next, after prebaking at 100 ° C. for 3 minutes, exposure was performed with a high pressure mercury lamp, and post baking was further performed at 230 ° C. for 2 hours. Subsequently, the color characteristics (x, y, Y) of the resists of Examples 1 to 10 and Comparative Examples 1 to 5 were measured with a spectrophotometer (UV-2500 PC, C light source: 2 ° field of vision manufactured by Shimadzu Corporation). In Examples 1 to 10 and Comparative Examples 1 to 3, the film thickness and the luminance Y value were determined when the chromaticity x was 0.6550 and y was 0.3230.
In addition, the luminance maintenance rate was defined as follows.
Brightness maintenance ratio (%) = (brightness after pre-baking / brightness after post-baking) × 100

According to the results shown in Table 2 above, according to Examples 1 to 10 which are the red colorant composition for color filter of the present invention, the brightness of the red colorant composition for color filter of the present invention is excellent and the brightness is excellent It was also possible to obtain a red colorant composition for a color filter which is excellent in retention rate, that is, the change in luminance is small even by post-baking treatment.
Moreover, according to Examples 1 to 10, which are the red colorant composition for color filters of the present invention, it was possible to obtain a red colorant composition for color filters which is excellent in the luminance retention ratio.
However, Comparative Example 1 in which the acid value of the compound having a phosphoric acid group or a salt thereof is insufficient, Comparative Example 2 in which the acid value of a compound having a phosphoric acid group or a salt thereof is excessive, a compound having a phosphoric acid group or a salt thereof According to Comparative Example 3 which does not contain H, and Comparative Example 4 in which the content of the compound having a phosphoric acid group or a salt thereof is excessive, the dispersion stability and the luminance retention rate are poor.
According to Comparative Example 5 in which the red colorant composition for a color filter of the present invention does not contain a dye, the dispersion stability was good, but the result was inferior in luminance maintenance rate.
According to these results, the present invention is excellent in dispersion stability and brightness by using a red colorant composition for a color filter having a specific composition, and exhibits an effect that the change in brightness is small even after the post-baking treatment. I understand that.

Claims (5)

Pigment Red 254 , a pigment dispersion aid having a sulfonic acid group, a dye, a pigment dispersant, a resin, a compound having a phosphoric acid group or a salt thereof, and a red colorant composition for a color filter mainly composed of an organic solvent. Te, before Symbol dye, C. I. Acid Red 52, C.I. I. Acid Red 87, C.I. I. A red colorant composition for a color filter, which is at least one selected from the group consisting of Acid Red 289.   The red colorant composition for a color filter according to claim 1, wherein the acid value of the compound having a phosphoric acid group or a salt thereof is 10 to 300 mg KOH / g.   Content of the compound which has the said phosphoric acid group or its salt is 10-1000 mass parts with respect to 100 mass parts of said dyes, The red coloring agent composition for color filters of Claim 1 or 2 characterized by the above-mentioned object.   The red pigment composition for color filters according to any one of claims 1 to 3, wherein the pigment is a micronized pigment. The red colorant composition for color filters according to any one of claims 1 to 4, wherein the pigment dispersion aid having an acid group is a pigment dispersion aid having a sulfonic acid group.