JPH11209558A - Photopolymerizable pigment dispersant, photosensitive coloring composition and composition for light-shielding layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photopolymerizable pigment dispersant having high dispersion stability, which is effective for improving resist characteristics, and suitable for producing a color filter. An object of the present invention is to provide a photosensitive coloring composition, particularly a composition for a light-shielding layer. SOLUTION: The photopolymerizable pigment dispersant of the present invention is a block polymer comprising a hydrophilic portion and a hydrophobic portion, and the block polymer has at least one ethylenically unsaturated double bond in a molecule. And the photosensitive coloring composition of the present invention comprises an alkali-soluble binder, a photopolymerizable monomer, a photopolymerizable initiator, a pigment, the above-described photopolymerizable pigment dispersant, and a solvent, Further, the composition for a light-shielding layer of the present invention comprises a composite metal oxide containing at least three metals of copper, manganese, and iron as a pigment in the photosensitive coloring composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photopolymerizable pigment dispersant, and particularly to a pigment dispersant having excellent pigment dispersion stability in an organic solvent system and having reactivity to UV and EB. It can also be used as a compatibilizer for various resists such as UV / EB curable paints, inks, solder resists, and polymer alloys. In particular, a dispersant for a coloring composition in a pigment dispersion color filter, a photopolymerizable pigment dispersant suitable as a dispersant for a light-shielding layer, a photosensitive coloring composition using the dispersant, and a composition for a light-shielding layer About.

[0002]

2. Description of the Related Art A method of producing a color filter by a photolithography method using a pigment-dispersed resist is stable with respect to light and heat due to the use of a pigment, and is patterned by the photolithography method. And a method suitable for producing a high-definition color display. However, in a color filter produced by the pigment dispersion method, if the dispersibility of the pigment is insufficient, problems occur in color purity and dimensional accuracy, and the display contrast ratio is significantly deteriorated due to depolarization. In addition, resist compositions with poor pigment dispersion stability not only adversely affect the film thickness uniformity during application in the color filter manufacturing process, the sensitivity during exposure, and the solubility during development, but also cause aggregation over time. There is also a problem that the viscosity increases and the pot life is extremely short.

[0003] Generally, pigments have poor dispersibility and miscibility in organic media such as organic solvents and high molecular compounds. Therefore, low molecular weight surfactants and high-density surfactants are used as means for enhancing the dispersibility of pigments. And a dispersant such as a pigment derivative.

[0004] However, low molecular weight surfactants have a problem that dispersion stability is low, and furthermore, surfactants are precipitated during use of color filters. JP-A-4-7606
In No. 2, dispersion stabilization was achieved by combining a low molecular weight ionic surfactant and an ionic resin having the same polarity.
The fact is that satisfactory results have not been obtained.

[0005] In the case of a polymer type surfactant, the dispersing effect of a three-component system of a pigment, a dispersant and a solvent is excellent. Depending on the type of the dispersion system is destroyed,
It has the disadvantage that the viscosity increases and the pigment sediments during storage. Therefore, Japanese Patent Application Laid-Open No. 9-146272 discloses that a graft copolymer having an acidic group in a side chain serves as both a dispersant and a binder resin to improve the dispersion stability of a pigment in a photosensitive coloring composition. Has improved.

The pigment derivative can enhance the dispersibility of the pigment when used in combination with other surfactants. However, the pigment derivative itself has a coloring ability and is used in a color filter where spectral characteristics are regarded as important. There is a limit.

In any case, the conventional dispersant does not have a photosensitive group in its molecule, so that a large amount of non-photocurable materials such as a binder resin and a dispersant are present in the resist composition. This lowers the sensitivity of the resist. In addition, when the dispersant has an acidic group and is soluble in an aqueous alkaline solution, the dispersant present in the exposed portion is eluted from the photocured portion during alkali development, so that the adhesion of the coating film to the substrate and the pattern shape are reduced. It has a major problem of adverse effects.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and an object of the present invention is to provide a photopolymerizable pigment dispersant having a high dispersion stability and an improved resist characteristic. It is an object of the present invention to provide a dispersant for a pigment-dispersed resist which is effective for the above, and a photosensitive coloring composition suitable for producing a color filter, particularly a composition for a light-shielding layer.

[0009]

As a result of diligent studies to achieve the above object, the photopolymerizable pigment dispersant of the present invention is a block polymer comprising a hydrophilic part and a hydrophobic part. The block polymer has at least one ethylenically unsaturated double bond in the molecule.

The above-mentioned hydrophilic part is represented by —OH group, —COOH
Group, -SO ₃ H group, -PO ₃ H ₂ group, -PO (OH)
It is a polymer containing at least one hydrophilic group selected from an (OR) group (R represents a hydrocarbon group) or a lower polyoxyalkylene group.

The weight average molecular weight of the block polymer is 5,000 to 200,000, and the weight ratio of the hydrophilic part to the hydrophobic part of the block polymer is 5/95 to 90/10.

[0012] The amount of the ethylenically unsaturated double bond group introduced is 0.1 to 5 mmol per 1 g of the block polymer.

The photosensitive coloring composition of the present invention comprises an alkali-soluble binder, a photopolymerizable monomer, a photopolymerizable initiator,
A dispersant, a pigment and a solvent as main components, the dispersant comprising a hydrophilic part and a hydrophobic part and containing at least one block polymer having at least one ethylenically unsaturated double bond in a molecule. It is characterized by.

The composition for a light-shielding layer of the present invention comprises an alkali-soluble binder, a photopolymerizable monomer, a photopolymerizable initiator, a dispersant, an inorganic black pigment, and a solvent as main components, and the dispersant comprises a hydrophilic part. And at least one block polymer having at least one ethylenically unsaturated double bond in the molecule.

The inorganic black pigment is a composite metal oxide containing at least copper, manganese and iron.

The photopolymerizable monomer is a polyfunctional acrylate and / or a polyfunctional methacrylate having 3 to 6 reactive double bond groups.

At least a part of the above-mentioned alkali-soluble binder contains 0.05 to 5 mmol of a reactive double bond group per 1 g, and has an acid value of 50 mg KOH.
/ G to 250 mgKOH / g epoxy resin.

The epoxy resin is bisphenol A
It is characterized by being a type vinyl ester.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The photopolymerizable pigment dispersant of the present invention comprises
A block polymer comprising a hydrophilic portion and a hydrophobic portion, wherein the block polymer has at least one ethylenically unsaturated double bond in the molecule,
The inventors have found that the dispersion of the pigment is stabilized and that the resist characteristics are further improved, thereby completing the present invention.

The hydrophilic portion in the photopolymerizable pigment dispersant is, for example, hydroxyethyl acrylate or hydroxyethyl methacrylate (hereinafter referred to as hydroxyethyl (meth) acrylate). The same applies hereinafter),
-OH group-containing monomers such as hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, N-hydroxymethylacrylamide, 2-hydroxy-3-phenoxypropyl (meth) acrylate, acrylic acid, α- or β-substituted Acrylic acid, for example α
-Acetoxy form, α-acetoxymethyl form, α-chloro form, β-chloro form, etc., methacrylic acid, maleic acid, itaconic acid, crotonic acid, maleic acid half ester, maleic acid half amide, itaconic acid half ester , Ethylenically unsaturated carboxylic acids such as half-amides of itaconic acid, vinylbenzenesulfonic acid, vinylsulfonic acid, vinylphosphonic acid, 2- (meth) acryloyloxyethyl phosphate,
Monopolymers of monomers such as methyl-2- (meth) acryloyloxyethyl phosphate and ethyl- (meth) acryloyloxyethyl phosphate, copolymers with other ethylenically unsaturated monomers, poly (ethylene oxide), etc. Of poly (alkylene oxide). But,
The polymer is not limited to these, and those obtained by chemically introducing a hydrophilic group into polyester, polyurethane or the like can also be used.

Examples of the hydrophobic part include methyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate and benzyl acrylate. Acrylic esters and methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate,
It is a polymer component comprising one or a combination of methacrylic esters such as tridecyl methacrylate, stearyl methacrylate, and benzyl methacrylate, and aromatic vinyl compounds such as styrene, α-styrene and vinyltoluene. Also in this case, the polymer is not limited to these polymers, and polymers having high hydrophobicity such as polyester and polyurethane can also be used.

Among the methods for synthesizing block polymers, the most reliable method is to use living anionic polymerization. However, experimentally requires a vacuum-based technique, and there are many difficulties in mass synthesis. Synthesis of the block polymer using radical polymerization is based on a method of coupling a terminal functional prepolymer,
It can be performed by a polymer initiator method, an iniferter method, or the like.

The terminal-functional prepolymer is synthesized using a polymerization initiator or a chain transfer agent containing a functional group such as a carboxyl group, a hydroxyl group or an amino group in the molecule. For example, in a polymerization initiator, a carboxyl group is introduced by azobiscyanopentanoic acid, a hydroxyl group is introduced by azobiscyanopentanol, and an amino group is introduced by apebisisobutyroamidine. In the chain transfer agent, a carboxyl group is introduced by thiodiglycolic acid, a hydroxyl group is introduced by mercaptoethanol, and an amino group is introduced by bis-4-aminophenyl-disulfide. This method
It is applicable to monomers such as (meth) acrylic acid type and vinyl type, and various prepolymers containing a hydrophilic group or a hydrophobic group can be synthesized.

Further, as the terminal functional prepolymer,
One-terminal hydroxyl group polymers such as polyoxyethylene monomethyl ether, terminal hydroxyl group polyesters, terminal hydroxyl group or terminal isocyanate group polyurethane and the like are also included.

Next, a block polymer is synthesized by coupling a terminal functional prepolymer having a functional group which can be condensed or added to each other. AB type, AB with a combination of one-end functional prepolymer and bi-terminal functional prepolymer
Various block polymers such as A type can be synthesized.

However, in the coupling reaction between the hydrophilic prepolymer and the hydrophobic prepolymer, protection of the hydrophilic group may be required. A block polymer is synthesized by reacting a prepolymer protected with a hydrophilic group with a hydrophobic prepolymer, and then deprotection is performed. The protective group introduction reaction and the deprotection group reaction of the hydrophilic group can be performed by a conventionally known method.

The polymer initiator method for synthesizing a block polymer by adding a monomer to a polymer having an azo group or a peroxy group is specifically described in Akira Ueda and Susumu Nagai, “Polymer” 39, 202 (1990), Takashi Yamamoto "Polymer" 3
5, 1010 (1986) and the literature cited therein. Also, a method using a bifunctional polymerization initiator described in U.S. Pat. No. 3,994,994 can be mentioned.

The iniferter method can be specifically synthesized according to the method described in the review of Takatsu Otsu “Polymer” 37, 248 (1988) and the literature cited therein.

The optimum value of the content of the hydrophilic group in the block polymer varies depending on the type of the hydrophilic group, but is preferably 1% by weight to 80% by weight per block polymer. When the content of the hydrophilic group is less than 1% by weight, dispersion stabilization becomes insufficient. When the content of the hydrophilic group exceeds 80% by weight, the steric hindrance layer contributing to the effect of preventing the aggregation of the pigment decreases, and the dispersion stability decreases. On the other hand, if the amount of the hydrophilic group is too large, it becomes soluble only in a highly polar solvent, and the solvent used is significantly restricted.

The weight average molecular weight (hereinafter, referred to as Mw) of the block polymer is preferably from 5,000 to 200,000. If Mw is less than 5,000, the effect of dispersibility is not sufficiently exhibited, and if Mw exceeds 200,000, solubility is reduced and resist characteristics are deteriorated.

The weight ratio of the hydrophilic part to the hydrophobic part in the block polymer is preferably from 5/95 to 90/10. Outside this range, the morphological effect of being a block polymer is reduced.

Next, introduction of an ethylenically unsaturated double bond into the block polymer is carried out by a conventionally known method. In the case of a block polymer containing a carboxyl group in the molecule, for example, a method of reacting an ethylenically unsaturated group-containing compound having an epoxy group, an ethylenically unsaturated group-containing compound having a hydroxyl group, or the like can be mentioned.
Examples of such a compound include glycidyl (meth) acrylate, 2-methylglycidyl (meth) acrylate, allyl glycidyl ether, allyl-2-methyl glycidyl ether, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate,
Hydroxybutyl (meth) acrylate and the like. When the compound has a hydroxyl group, for example, a method of reacting an ethylenically unsaturated group-containing compound having a functional group capable of reacting with a hydroxyl group such as isocyanate ethyl methacrylate, (meth) acrylic acid, and (meth) acrylic acid chloride is used. is there.

The introduction of an ethylenically unsaturated group into the block polymer is also possible by using a terminal functional prepolymer containing an ethylenically unsaturated group.
Examples of the terminal functional prepolymer containing an ethylenically unsaturated group include a one-terminal hydroxyl group obtained by condensing ethyl-α- (hydroxylethyl) acrylate described in US Pat. No. 3,321,552. There is polyester. Further, tolylene diisocyanate, a diisocyanate such as diphenylmethane diisocyanate and an ethylenically unsaturated group-containing compound containing two hydroxyl groups such as glyceryl methacrylate alone or butylene adipate, ethylene adipate,
There is a polyurethane obtained by a reaction with a mixture of a polyester diol and a polyether diol having hydroxyl groups at both terminals such as polytetramethylene glycol and polyethylene glycol.

The amount of the ethylenically unsaturated group to be introduced is preferably from 0.1 mmol to 5 mmol per 1 g of the block polymer. If the amount is less than 0.1 mmol, the photocurability is low, and the effect of improving the coating film adhesion and the resist properties is small.

The photopolymerizable pigment dispersant of the present invention can be applied to various inorganic pigments and organic pigments. Specifically, iron, cobalt, aluminum, cadmium, lead, copper, titanium,
Magnesium, chromium, zinc, antimony, metal oxides such as manganese, and composite oxides of the above metals, barium sulfate, silica, zinc chromate, strontium chromate,
Inorganic compounds such as carbon black, metallic aluminum, metallic lead, metallic zinc, basic lead sulfate, aluminum hydroxide, basic lead carbonate, or organic pigments such as quinacridone, phthalocyanine blue, phthalocyanine green, azo pigments,
Color indices such as isoindoline pigments and dioxazine pigments (CI; The Society of Dyersand Colou)
rists).

Although the pigment dispersing mechanism of the pigment dispersant of the present invention is largely unknown, the pigment is in a hydrophilic state due to the presence of a hydrophilic functional group such as a hydroxyl group, adsorbed moisture and the like, and the block polymer is hydrophilic. Part and hydrophobic part,
It is considered that the ability to adsorb to the pigment by the hydrophilic portion and stabilize the dispersion by dissolving the hydrophobic portion in the solvent is high. However, the hydrophilic-hydrophobic balance of the pigment surface and the solvent,
The dispersing mechanism differs depending on the solubility of the block polymer in the solvent, and thus cannot be determined unconditionally.

The pigment usually forms an aggregate, and it is not easy to make the pigment into fine particles. Therefore, the photosensitive coloring composition of the present invention is a pigment, a photopolymerizable dispersant, a coloring solution comprising a solvent is prepared in advance, and the coloring solution is an alkali-soluble binder, a photopolymerizable monomer, a photopolymerizable initiator, a solvent. Is prepared by mixing.

In the preparation of the above-mentioned colored liquid, the dispersant of the present invention is previously mixed homogeneously with a finely divided pigment or the like, or dissolved in a dispersion medium beforehand, or used as a dispersion comprising a pigment or the like and a non-aqueous solvent. It is preferable to use it by adding it to the system.

The present dispersant can be used alone or as a mixture with a general low-molecular surfactant, high-molecular surfactant, or pigment derivative. As such a dispersant, commercially available (meth) acrylic acid-based (co) polymer Polyflow No. 75, no. 90, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo), Megafac F171, F17
2, F173 (manufactured by Dainippon Ink and Chemicals), Florad Fc430, Fc431 (manufactured by Sumitomo 3M), Solspass 12000, 13240, 20000, 2400
Solsperse dispersants such as 0, 26000 and 28000 (manufactured by Zeneca), Disperse Big 111 and 16
1, 164, 165 (made by Big Chemie) or the like can be used.

In the preparation of the coloring liquid, any disperser may be used, for example, a pole mill, a sand mill,
Visco mills, roll mills, kneaders, attritors, high-speed mixers, homomixers and the like can be mentioned.

The photopolymerizable pigment dispersant is added in an amount of 2% by weight to 80% by weight, preferably 2% by weight to 40% by weight, based on the total solid content of the liquid photosensitive composition. If the amount is less than 2% by weight, the dispersion stability is insufficient, and the viscosity increases and the pigment sediments over time. However, the optimal amount of the dispersant varies depending on the combination of the pigment, solvent, and resist component used. Further, as described above, the photopolymerizable pigment dispersant may be used alone or in combination with another non-aqueous dispersant. In this case, the other non-aqueous dispersant can be used in an amount of 0 to 80% by weight of the dispersant of the present invention. If it is used in excess of 80% by weight, the sensitivity which is the object of the present invention is reduced.

When the photopolymerizable pigment dispersant of the present invention is used in a photosensitive coloring composition, it also serves as a binder resin in addition to the dispersant, and serves as another component of the resist (binder resin, polyfunctional monomer, etc.). ) To remove stickiness,
It also acts as a coating property modifier. The adhesiveness after drying the solvent is preferably non-adhesive because defects are likely to occur due to adhesion of foreign substances in the color filter manufacturing process. Further, since it contains an ethylenically unsaturated group, it has photocurability and, for example, when used in a pigment-dispersed resist, improves the sensitivity of the resist. Also,
It is possible to improve the disadvantages of the dispersant having no photocurability, such as a decrease in the adhesion of the coating film to the base material due to the alkali development and a deterioration in the pattern shape.

Hereinafter, as the photosensitive coloring composition of the present invention,
In particular, the case where the composition is a light shielding layer composition will be described in detail.

The photopolymerizable pigment dispersant of the present invention exhibits an excellent effect on a composition for a light-shielding layer using an inorganic black pigment.
This is because the amount of exposure in the film is remarkably reduced due to the light shielding property, the curing is insufficient, and the adverse effect of the non-reactive component is likely to occur,
This is because sensitivity is increased by the dispersant of the present invention. Already proposed by the present inventors, at least copper, manganese,
The composition for a light-shielding layer using composite metal oxide fine particles containing an iron metal exhibits particularly excellent effects in terms of dispersibility.

The pigment in the composition for a light-shielding layer of the present invention includes:
According to the wet method disclosed in JP-A-9-25126, an alkali is added to three kinds of water-soluble metal salts of copper, manganese, and iron, and the precipitate is neutralized and precipitated. After oxidizing in the liquid phase,
It can be manufactured by washing, drying, baking and pulverizing.

In order to make the surface state of the pigment more easily dispersed, a water-soluble metal salt of zirconium or zinc may be added.

Further, in order to collect a large amount of zirconium and zinc metal oxides on the particle surface, an alkali is added to a water-soluble metal salt of copper, manganese, and iron, and the mixture is neutralized and precipitated. During the process of adding a oxidizing agent such as hydrogen oxide and oxidizing in the liquid phase to produce a composite metal oxide,
Alternatively, it can be prepared by a method of adding a water-soluble metal salt of zirconium and zinc after preparation.

The composite metal oxide composed of copper, manganese, and iron is obtained, for example, by substituting a part of Mn of CuMn ₂ O ₄ with Fe. The composition ratio of CuO is 25% by weight to 40% by weight. 5 wt% to 30 wt% of Fe ₂ O ₃ ,
And those having Mn ₂ O _{3 in} the range of 40% by weight to 60% by weight.

The content of the composite metal oxide of zirconium and zinc is 0.1% by weight to 50% by weight, preferably 0.3% by weight to 10% by weight, based on the composite metal oxide of copper, manganese and iron. %. When the amount is less than 0.1% by weight, a desired light-shielding layer cannot be obtained due to poor affinity with an alkali-soluble binder and the like. When used as a filter, it is not preferable because of poor developability.

The pigment in the present invention is a composite metal oxide containing at least three kinds of metals of copper, manganese and iron, and zirconium and zinc metal oxides can be added as needed. A metal oxide such as nickel may be contained.

The black pigment used in the composition for a light-shielding layer of the present invention has optimum values for the particle diameter, the specific surface area and the amount of surface hydroxyl groups.

The particle size is 0.01 μm to 0.5 μm.
μm, preferably in the range of 0.01 μm to 0.3 μm. If the particle diameter is less than 0.01 μm, the light-shielding property is not sufficient, and if it exceeds 0.5 μm, it is not preferable because the smoothness of the film surface is impaired or the precision of pattern formation is greatly reduced.

The specific surface area is 15 m ² / g to 40 m
² / g, preferably in the range of 18m ² / g~35m ² / g. Here, it is considered that the specific surface area exceeds 40 m ² / g when a pigment having an appropriate particle size or less is contained, and when the pigment has a porous or amorphous structure even within the range of the appropriate particle size. If the particle size is less than the appropriate particle size, light-shielding properties cannot be sufficiently obtained, and even if the pigment has a porous structure or an amorphous structure even within the range of the appropriate particle size,
At the same time, the pigment itself has a strong cohesive force and, at the same time, firmly adsorbs the binder component to form an aggregate, which is not preferable because the dispersibility of the pigment is significantly inhibited. When the specific surface area is less than 15 m ² / g, it is not preferable because a pigment having an appropriate particle size or more is contained.

Further, even when the particle diameter and the specific surface area are within the appropriate ranges, the pigment used in the present invention has a surface hydroxyl group content of 0.1 μmol / g to 40 μmol / g, preferably 0.5 μmol / g. g to 25 μmol / g. When the amount of surface hydroxyl groups is less than 0.1 μmol / g, the affinity of the pigment surface for the solvent or dispersant is extremely reduced, so that the aggregation or precipitation of the pigment occurs, and the pigment content is reduced to 40 μmol / g.
When the specific surface area is more than 1 / g, as in the case where the specific surface area is too large,
It is not preferable because the cohesive force of the pigment itself and the adsorbing force of other binder components become too strong.

The amount of hydroxyl groups on the pigment surface in the present invention is determined by the following quantitative method.

(Quantitative method) For 2.0 g of pigment, 0.01 g
Add 30 ml of N-tetrabutylammonium hydroxide-ethanol solution, stir for 1 hour, take 10 ml of supernatant, add 30 ml of ethanol, and determine the amount of residual tetrabutylammonium hydroxide determined with 0.01N perchloric acid-ethanol solution. The value obtained by subtracting the amount of tetrabutylammonium hydroxide contained in 30 ml of the above 0.01N tetrabutylammonium hydroxide-ethanol solution is defined as the amount of hydroxyl groups on the pigment surface.

Such pigments are commercially available, for example, "Dipiroxide TM Black # 3950", "Dipiroxide TM Black # 3952", "Dipiroxide TM" manufactured by Dainichi Seika Kogyo Co., Ltd. Black # 9550 "," Dipiroxide Side Black # 35 "
50 ", BASF" SICOCER F Black 2904 "," SI
COCER F Black 2912 "and" SICOPUR SE 1435 ".

Even when the above conditions are satisfied, aggregation of the pigments is likely to occur particularly when a large amount of pigments is contained in order to realize sufficient light-shielding properties.
Therefore, in the composition for a light-shielding layer of the present invention, a hydrophobic group such as an alkyl group or a phenyl group is further introduced into the surface of the pigment particle by a covalent bond, or the transition metal hydroxide particles or the transition By coating the metal oxide particles, the affinity with the dispersant can be increased, and the aggregation state of the pigment can be reduced.

In order to introduce a hydrophobic group into the pigment surface by a covalent bond, for example, the hydroxyl group on the pigment surface may be alkylated or phenylated by treating it with a silane-based, titanate-based, or aluminum-based coupling agent. The amount of substitution is suitably from 0.01% by weight to 20% by weight.

Further, the surface of the pigment is made to have a particle size of 0.005 μm.
m to 0.02 μm of Zr, Zn, Fe, Co, or Ni
And / or the like. Further, the transition metal may be used alone or in combination.

As a coating method, a pigment is dispersed in an aqueous solution of a transition metal salt, and an alkali solution is dropped to neutralize and deposit and deposit as transition metal hydroxide fine particles and / or transition metal oxide fine particles on the pigment surface. May be coated by a known method. The coating amount on the pigment particle surface is 0.01
% To 20% by weight.

Next, the alkali-soluble binder contributes to the dispersibility of the pigment particles, has good compatibility with the photopolymerizable monomer and the photopolymerizable initiator, and has solubility in an alkali developing solution and solubility in an organic solvent. It is required to be excellent. Further, in the pattern forming process including exposure and development, it is required to have excellent adhesion to the substrate even when exposed to an alkali developing solution or a cleaning solution for a long time, and further, the strength and softening as a color filter member are required. Those having an appropriate temperature and the like are preferable.

Examples of the alkali-soluble binder include an epoxy resin, particularly a condensation reaction product of bisphenol A and epichlorohydrin whose basic skeleton is a ring-opening reaction of two or more epoxy groups contained in the molecule. Preferably, a reactive double bond group or a cyclic acid anhydride is added using glycidyl methacrylate or the like, and polymerization initiation ability or alkali developability is imparted using a resulting carboxyl group or the like. For example, a bisphenol A type vinyl ester is mentioned, which satisfies the above-mentioned characteristics in realizing alkali resistance, substrate adhesion, and film strength.

Further, in the alkali-soluble binder of the present invention, various strengths of the light-shielding layer formed by forming a polymerizable binder by introducing a reactive double bond group can be further improved. The reactive double bond groups introduced are in the range from 0.05 mmol to 5 mmol, preferably from 0.2 mmol to 3 mmol, per gram. Further, in order to impart a suitable alkali developing solution resistance, the acid value is 50 mgKOH / g to 250 mgKOH / g,
Preferably from 60 mgKOH / g to 150 mgKOH / g
Range.

If the acid value exceeds 250 mg KOH / g, the pattern is resolved after exposure and development, but there is no resistance to the alkali developing solution, and small cracks are generated on the developed pattern surface. Is rapidly generated and eventually causes the resist to be peeled (peeled) from the glass substrate surface. In addition, the acid value is 50 mgK
If it is less than OH / g, the solubility to alkali is lost, and no dissolution occurs even in the unexposed area, so that an appropriate pattern cannot be formed.

The average molecular weight of the alkali-soluble binder is 2000 to 20,000, preferably 3000 to 1
It is in the range of 5,000. If it is less than 2,000, it does not function sufficiently as a binder, and if it exceeds 20,000, it is easy to form aggregates of pigments, and the composition life due to pigment aggregation, substrate adhesion, pattern formability and smoothness of coating film It is not preferable because it causes a decrease. Further, when the above-mentioned epoxy resin is used as the alkali-soluble binder, it also has an effect of stabilizing the dispersion of the pigment in the composition for a light-shielding layer.

Examples of the epoxy resin preferable as the alkali-soluble binder include, for example, “Bisphenol A type epoxy acrylate, VR-60T” manufactured by Showa Polymer Co., Ltd.
H, 0.29 mmol of double bond groups per gram, acid value 7
0 mgKOH / g, average molecular weight 7,000 "," bisphenol A type epoxy acrylate, VR-90TH,
0.57 mmol of double bond groups / g, acid value 125
mgKOH / g, average molecular weight 3500 "," cresol type novolak type epoxy acrylate, 0.6 mmol of double bond group per 1 g, acid value 110 mgKOH / g,
"Average molecular weight 7500", "phenol novolak type epoxy acrylate, 0.6 mmol of double bond group per 1 g, acid value 120 mgKOH / g, average molecular weight 550
0 "and the like.

The content of the alkali-soluble binder is in the range of 5% by weight to 80% by weight, preferably 5% by weight to 60% by weight of the total solids in the composition for a light-shielding layer.

The alkali-soluble binder of the present invention includes
For example, even those having a high molecular weight described in Japanese Patent Application No. 8-95884 may be used in combination as long as the action of an epoxy resin preferable as an alkali-soluble binder is not impaired.

Next, as the photopolymerizable monomer, a polyfunctional acrylate or a polyfunctional methacrylate having three or more double bond functional groups in one molecule (hereinafter, an acrylate and a methacrylate are referred to simultaneously) (Referred to as (meth) acrylate). In a polyfunctional (meth) acrylate, if the number of functional groups exceeds 6, the film itself becomes hard, but becomes brittle, so that sufficient strength cannot be exhibited, and
If it is less than 3, the effect is insufficient, and in this case, the strength is considered to be insufficient. However, in practical use, it is only necessary to have three or more double bond groups. Particularly, dipentaerythritol penta (meth) acrylate having five double bond groups and a derivative thereof are preferable.

In addition, for example, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane diacrylate, neopentyl glycol di (meth) acrylate,
Pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexaacrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, Ethylene oxide and propylene oxide were added to polyfunctional alcohols such as tri (acryloyloxyethyl) isocyanurate, tri (acryloyloxyethyl) cyanurate, glycerin tri (meth) acrylate, trimethylolpropane and glycerin, and then subjected to (meth) acrylate conversion. And polyester acrylates. The acrylate and methacrylates described above may be used alone or as a mixture. In addition to monomers, prepolymers, that is, dimers and trimers are also effective. The content of the above monomer is in the range of 5% by weight to 50% by weight, preferably 5% by weight to 40% by weight of the total solids in the composition for a light-shielding layer.

The above-mentioned photopolymerizable pigment dispersant of the present invention is used in an amount of from 2% by weight to 2% by weight based on the total solid content of the composition for a light-shielding layer.
80% by weight, preferably 2% to 40% by weight is added. If the amount is less than 2% by weight, the dispersion stability is insufficient, and the viscosity increases and the pigment sediments over time. Further, as described above, a general dispersant having no photocurability may be added at a ratio of 0 to 80% by weight based on the photopolymerizable dispersant. If it exceeds 80% by weight, the reactivity, which is the main feature of the present invention, is reduced, and the effect is not recognized.

Examples of the photopolymerizable initiator include thioxanthone-based, acetophenone-based, benzophenone-based, benzoin ether-based, peroxide-based, and biimidazole-based compounds. It is effective to add a quinone-based photopolymerization accelerator.

The content of the photopolymerization initiator and the photopolymerization accelerator is
It is 0.5% by weight to 40% by weight, preferably 5% by weight to 40% by weight of the total solids of the composition for a light-shielding layer.

As the solvent, taking into consideration the applicability of the composition for a light-shielding layer, the solubility of a polymer or monomer such as an alkali-soluble binder, a photopolymerizable pigment dispersant, a photopolymerization initiator, and the dispersibility of the pigment, One or more solvents described below can be appropriately selected and used, but it is preferable that one or more polyhydric alcohols or derivatives thereof are contained. In particular, considering the dispersibility of the pigment, a polyhydric alcohol or a derivative thereof having a solubility of 20 parts by weight or more in 100 parts by weight of water at 20 ° C. is effective.

Specific examples of the solvent include ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether, glycol monoethyl ether acetate, ethylene glycol monopropyl ether, ethylene glycol monopropyl ether acetate, and ethylene glycol monobutyl ether. , Ethylene glycol monobutyl ether acetate, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, ethylene glycol isoamyl ether, methoxymethoxy ether, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol Monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, 1-butoxyethoxypropanol, dipropylene Glycol monomethyl ether, 3-
Examples thereof include methyl-3-methoxybutanol, 3-methyl-3-methoxybutyl acetate, methyl amyl ketone, methyl lactate, ethyl lactate, methyl-α-hydroxyisobutyrate, and methyl-β-methoxyisobutyrate.

In addition to the above components, the composition for a light-shielding layer of the present invention may further comprise a silane coupling agent or a titanate coupling in order to impart adhesion to a substrate to which the composition is applied. , An aluminum coupling agent and the like can be added.

In order to prevent stickiness in the coating film, the pigment dispersant of the present invention also acts. However, a physical property improving agent for the coating film may be further added. For example, "L-20-" manufactured by Soken Chemical Co., Ltd.
3 (graft polymer), 0 mol% of double bond group, acid value 0
mgKOH / g, average molecular weight 56,000 "," L-4
03A, double bond group 0 mol%, acid value 0 mgKOH / g,
"Average molecular weight 30,000", "LH-448, 0 mol% of double bond group, acid value 0 mgKOH / g, average molecular weight 30,
000 "or the like, from 0.1% to 50% by weight, preferably from 0.1% to 30% by weight of the total solids of the composition for a light-shielding layer.
May be added.

The composition for a light-shielding layer of the present invention can be applied on a substrate by a known method and dried to form a light-shielding layer on the substrate. Specific examples of the coating method include a spinner, a wheeler roller coater, a curtain coater, a knife coater, a bar coater, an extruder, and the like.
μm, preferably 0.5 μm to 3 μm.

When exposing the substrate on which the light shielding layer is formed,
The light source is selected according to the photosensitivity of the light-shielding layer, and a known light source such as an ultra-high pressure mercury lamp, a xenon lamp, a carbon arc lamp, and an argon laser can be used.

An alkali water-based developer is preferably used as a developer for developing the light-shielding layer subjected to pattern exposure. The alkaline aqueous developer, for performing development with an aqueous, OH at the time of development in a narrow sense ^- a developer releasing. The pH of the alkaline aqueous developer is optimally 7.5.
領域 12. The alkali component used is, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, or an organic ammonium compound such as tetraethylammonium hydroxide, and other anions of sulfide, oxide or weak acid (for example, F ⁻ , CN ^- ) And the like. Further, a buffer solution in this pH range may be prepared and used as an alkaline aqueous developer.

The composition for a light-shielding layer of the present invention is used for forming a black matrix for partitioning red, green and blue pixels on a transparent substrate, and thereafter, according to a known method.
Red, green, and blue pixels are formed. A transparent electrode layer is further provided on the surface to form a color filter. However, if necessary, a protective film is formed before providing the transparent conductive layer.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. “Parts” in the examples means parts by weight.

[0084]

EXAMPLES (1) Preparation of photopolymerizable pigment dispersant (Synthesis of block polymer) A 2-hydroxymethacrylic acid was placed in a glass reactor equipped with a thermometer, a stirrer, a dropping funnel, a gas inlet tube and a reflux condenser. 39 parts of ethyl and 390 parts of ethyl cellosolve were charged, and the inside of the reaction vessel was heated to 80 ° C. under a stream of argon gas with stirring. Thereafter, a mixed solution of 0.87 parts of Perhexa MC (a bifunctional polymerization initiator, manufactured by NOF Corporation) and 120 parts of ethyl cellosolve was dropped. After reaction at 80 ° C. for 30 minutes, the mixture was quenched.

Next, the reaction solution was added dropwise to hexane to carry out precipitation purification. 35 parts of peroxy group-terminated 2-hydroxyethyl methacrylate obtained by drying under reduced pressure was dissolved in 390 parts of ethyl cellosolve, 30 parts of methyl methacrylate was added to this solution, and the temperature was raised to 100 ° C. for 10 hours. Reacted. The reaction solution was dropped into hexane to perform reprecipitation purification. After filtration, the filtrate was dried under reduced pressure at room temperature. The obtained polymer was extracted with methyl isobutyl ketone. The methylisobutylketone-soluble portion was rich in polymethacrylic acid, which was removed to obtain 50 parts of a block polymer.

The obtained block polymer was poly (hydroxyl methacrylate) / poly (methyl methacrylate) (weight ratio: 45/55), and had a weight average molecular weight of 30,
000.

(Introduction of Ethylenically Unsaturated Double Bond) Next, 5 parts of the obtained block polymer, 100 parts of methyl ethyl ketone, 10 parts of dimethylformamide and 0.1 part of hydroquinone were made of glass equipped with a thermometer and a stirrer. The reaction vessel was charged, and when the polymer was dissolved, 1.5 parts of ethyl methacrylate isocyanate was added. 5 with stirring
The reaction was carried out at 0 ° C. for 18 hours. The reaction solution was added dropwise to hexane, and the precipitate was purified.

After filtration, the mixture was dried under reduced pressure at room temperature, and 5.5 g of a photopolymerizable pigment dispersant having a weight average molecular weight of 30,000 containing 3 mmol of a methacryloyl group per 1 g of a block polymer.
Got a part.

The resist properties were evaluated using the obtained photopolymerizable pigment dispersant as a dispersant for a pigment-dispersed resist.

Example 1 (1) Preparation of Black Pigment Dispersion Black Pigment: TM Black # 3952 (Zr was deposited near the surface of composite oxide fine particles in which a part of Mn of CuMn ₂ O _{4 was} replaced with Fe). 100 parts by weight of pigment obtained by adding 2.5% by weight to the composite metal oxide in terms of ZrO ₂ and 1.0% by weight in terms of ZnO in terms of ZnO; manufactured by Daime Seika Kogyo Co., Ltd. Photopolymerizable pigment dispersant 3.5 parts by weight Dispersant (polymer dispersant; Disperbyk 111, manufactured by BYK Japan KK) 3.5 parts by weight Diethylene glycol dimethyl ether 136 parts by weight-ethyl lactate ... 15 parts by weight The above components were mixed and sufficiently dispersed by a sand mill.

(2) Preparation of composition for light-shielding layer-Black pigment dispersion prepared in (1) ... 61 parts by weight-Alkali-soluble binder {VR-60TH (Bisphenol A) manufactured by Showa Polymer Co., Ltd. 2.8 parts by weight-Photopolymerizable monomer (dipentaerythritol pentaacrylate) ... 3.5 parts by weight-Photopolymerizable initiator-2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -ptanone) 1.6 parts by weight 4,4'-diethylthioxanthone 0.3 parts by weight 2,2,4-diethylthioxanthone 0.1 parts by weight Biimidazole 0.4 parts by weight Diethylene glycol dimethyl ether 30 parts by weight The above components are sufficiently mixed to obtain the composition for a light-shielding layer of the present invention. Was.

(3) Preparation of light-shielding layer The composition for light-shielding layer prepared in (2) was applied on a glass substrate by a spin coater and dried at 100 ° C. for 3 minutes to form a light-shielding layer having a thickness of about 1 μm. .

(4) Exposure and development The above light-shielding layer was exposed to a light-shielding layer pattern with an ultra-high pressure mercury lamp under a nitrogen stream to form an exposure of 500 mJ / cm ² , 300 m
After exposure in two ways, J / cm ² , the film was developed with a 1% aqueous potassium hydroxide solution.

Comparative Example 1 (1) Preparation of Black Pigment Dispersion Black Pigment: TM Black # 3952 (Zr was deposited near the surface of the composite oxide fine particles in which part of Mn of CuMn ₂ O _{4 was} replaced with Fe). Pigment with 2.5% by weight based on the composite metal oxide in terms of ZrO ₂ and 1.0% by weight in terms of ZnO in terms of ZnO; manufactured by Daime Seika Kogyo Co., Ltd. 100 parts by weight Dispersant ( Polymer dispersant; Disperbyk 111, manufactured by Big Chemie Japan Co., Ltd. 7 parts by weight Diethylene glycol dimethyl ether 136 parts by weight Ethyl lactate 15 parts by weight Was sufficiently dispersed.

(2) Preparation of composition for light-shielding layer The preparation of the composition for light-shielding layer in Example 1 was the same except that the black pigment dispersion prepared in (1) was used instead of the black pigment dispersion. Then, a composition for a light-shielding layer was prepared, and a light-shielding layer was prepared, exposed, and developed in the same manner as in Example 1.

In Example 1 and Comparative Example 1, the exposure amount was 5
00mJ / cm ^2, development characteristics of each case to 300 mJ / cm ² (resolution: [mu] m line and space resolution) result of comparison are shown in the table below.

[0097]

[Table 1]

As can be seen from the table, it is clear that Example 1 of the present invention has better development characteristics than Comparative Example 1.

Further, in the light-shielding layer produced in Comparative Example 1, the pattern portion (pigment aggregated portion) was easily peeled off during the pattern formation at the time of development. No peeling or missing during cleaning.

[0100]

The photopolymerizable pigment dispersant of the present invention is excellent in the dispersion stability of a coating material and also in the substrate adhesion of a coating film and the pattern-forming property. Useful as a dispersant in layer compositions.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 7/12 C09D 7/12 A 163/10 163/10 G02B 5/00 G02B 5/00 B 5/20 101 5/20 101 5/22 5/22 G03F 7/027 501 G03F 7/027 501 // C08F 2/44 C08F 2/44 A C09D 11/00 C09D 11/00 (72) Inventor Masayuki Ando Masakazu Ichigaya, Shinjuku-ku, Tokyo No.1-1, Dai Nippon Printing Co., Ltd.

Claims (10)

[Claims] 1. A photopolymer comprising a block polymer comprising a hydrophilic portion and a hydrophobic portion, wherein the block polymer has at least one ethylenically unsaturated double bond in a molecule. Pigment dispersant. 2. The method according to claim 1, wherein the hydrophilic portion has an —OH group, a —COOH group,
—SO ₃ H group, —PO ₃ H ₂ group, —PO (OH) (O
2. The photopolymerizable polymer according to claim 1, wherein the polymer is a polymer containing at least one hydrophilic group selected from R) groups (R represents a hydrocarbon group) or lower polyoxyalkylene groups. Pigment dispersant. 3. The weight average molecular weight of the block polymer is 5,000 to 200,000, and the weight ratio of the hydrophilic part to the hydrophobic part of the block polymer is 5/95 to 90/10. The photopolymerizable pigment dispersant according to claim 1 or 2. 4. The amount of ethylenically unsaturated double bond group introduced,
The photopolymerizable dispersant according to any one of claims 1 to 3, wherein the amount is 0.1 mmol to 5 mmol per 1 g of the block polymer. 5. An alkali-soluble binder, a photopolymerizable monomer, a photopolymerizable initiator, a dispersant, a pigment and a solvent as main components, the dispersant comprising a hydrophilic part and a hydrophobic part,
A photosensitive coloring composition comprising at least one block polymer having at least one ethylenically unsaturated double bond in a molecule. 6. An alkali-soluble binder, a photopolymerizable monomer, a photopolymerizable initiator, a dispersant, an inorganic black pigment, and a solvent as main components, the dispersant comprising a hydrophilic part and a hydrophobic part, A composition for a light-shielding layer, comprising at least one block polymer having at least one ethylenically unsaturated double bond in a molecule. 7. The composition for a light-shielding layer according to claim 6, wherein the inorganic black pigment is a composite metal oxide containing at least copper, manganese, and iron. 8. The photopolymerizable monomer is a polyfunctional acrylate having three to six reactive double bond groups and / or a polyfunctional methacrylate. The composition for a light-shielding layer according to the above. 9. At least a part of the alkali-soluble binder contains 0.05 to 5 mmol of a reactive double bond group per 1 g, and has an acid value of 50 mg KOH / g.
The composition for a light-shielding layer according to claim 6 or 7, wherein the composition is an epoxy resin of up to 250 mgKOH / g. 10. The composition for a light-shielding layer according to claim 9, wherein the epoxy resin is a bisphenol A type vinyl ester.