JPH10319230A - Thermosetting colored composition for forming color filters - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting colored compsn. for forming color filters usable at the time of forming the color filters by a laser transfer method. SOLUTION: This colored compsn. contains 5 to 50 wt.%, on the basis of a total weight, solid content and the balance a solvent. In such a case, this solid content contains 20 to 60 wt.% binder resin expressed by the formula, 10 to 40 wt.% crosslinking agent, 0.1 to 10 wt.% polymn. initiator, 20 to 60 wt.% dyestuff material and 0 to 10 wt.% other additives. In the formula, R1 denotes hydrogen or methyl group, R2 denotes 1 to 12C alkyl group, 2 to 10C hydroxyalkyl group, etc., R3 denotes 1 to 12C alkyl group, 3 to 10C cycloalkyl, etc., X denotes vinyl group or epoxy group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting coloring composition, and more particularly, to a thermosetting coloring composition which can be used for producing a color filter using a laser transfer method.

[0002]

2. Description of the Related Art A color filter is indispensable for realizing a multi-color liquid crystal display device. Generally, a color filter is required to have a spectral characteristic close to that of a color television. It has good properties, has excellent light resistance so that no change in chromaticity characteristics is observed even when exposed to light for a long time, has a smooth color filter surface and has no foreign matter projections, has good heat resistance, and has a subsequent heat treatment. That the spectral characteristics do not change in the process, that the pixel accuracy of the color filter matches the transparent electrode, that the chemical resistance is high,
Good compatibility with the sealing adhesive and absence of pin holes and color unevenness.

Further, in recent years, as the thickness and size of liquid crystal display elements have been reduced, the above requirements have been added.
It is also required to improve the yield and shorten the process.

[0004] Such a color filter is usually prepared by coating a glass substrate with a photosensitive coloring composition obtained by dispersing a color material such as a pigment in a mixture of a thermoplastic copolymerizable compound and a photosensitive compound. A series of processes of developing with an alkaline solution after exposure to ultraviolet light is repeated to form a red, green, and blue color filter pattern.

However, according to this method, the production process is long and complicated, so that there is a problem that the yield is low. As a measure against this, a color filter production method using a laser transfer method has been proposed.

[0006] The laser transfer method has been mainly used in the fields of printing, typesetting, photography and the like. This is based on the principle of transferring a substance transferred from a donor film including a layer coated with a substance to be transferred (for example, a dye, a pigment or the like) onto a receptor (glass or polymer film) in a desired pattern. Because of the advantage that a desired pattern can be transferred to an accurate position, a method applied to forming a black matrix, a spacer, a color filter, and the like in manufacturing a liquid crystal display device has recently been studied. .

The structure of the donor film usually used in such a laser transfer method differs depending on the physicochemical properties of the material to be transferred and the energy source used at the time of transfer. In general, a base layer is formed of a propellant layer containing aluminum, carbon, IR dye, etc., which are substances that absorb light and converted to thermal transfer energy, and a transfer layer containing a substance to be transferred.

In particular, the transfer layer differs depending on the type of transfer body formed by transfer. For example, when the transfer body to be formed is a spacer, the transfer layer contains a substance for forming a spacer.

When the transfer member to be formed is a color filter, a donor film in which a coloring composition for forming a color filter is applied on the propelling layer is used.
The present invention relates to a color composition for forming a color filter, which can be used at the time of manufacturing a color filter by laser transfer.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a color filter for forming a color filter which can be used in manufacturing a color filter by using a laser transfer method which has a simpler process than a conventional pigment dispersion method and has a high yield. It is to provide a thermosetting coloring composition.

[0011]

The object of the present invention is to provide a colored composition for forming a color filter, comprising a solid content of 5 to 50% by weight and a remaining amount of a solvent, based on the total weight, Is 20 to 60% by weight of a binding resin represented by the following formula, 10 to 40% by weight of a crosslinking agent, 0.1 to 10% by weight of a polymerization initiator, 20 to 60% by weight of a color material and 0 to 60% by weight.
10% by weight of other additives (however, the binder resin, the crosslinking agent, the polymerization initiator, the color material, and the other additives are based on the total weight of the solid content). Achieved by a thermosetting coloring composition for forming a color filter that:

[0012]

Embedded image

Wherein R ₁ represents hydrogen or a methyl group; R ₂ represents an alkyl group having 1 to 12 carbon atoms;
To 10 hydroxyalkyl groups, substituted or unsubstituted cyclic aromatic groups (particularly, phenyl group, benzyl group,
A hydroxyphenyl group, a phenylethyl group, a phenylpropyl group, a tolyl group, a pyridylethyl group or a quinolinyl group), a cycloalkyl group having 3 to 10 carbon atoms or a benzyl group, and R ₃ represents an alkyl having 1 to 12 carbon atoms. X represents a hydrogen, a vinyl group or an epoxy group, and 0.1 ≦ a ≦ 0.65, 0.3 ≦ b ≦ 0.
8 and 0 ≦ c ≦ 0.2 (where a, b, and c
Is the mole fraction, a + b + c =
1).

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the thermosetting coloring composition for forming a color filter according to the present invention, first, the bonding resin of the above chemical formula is composed of (meth) acrylic acid, unsaturated organic acid ester and epoxy or vinyl group. An acrylic resin obtained by polymerizing an unsaturated organic acid ester containing

The unsaturated organic acid ester includes 2-
Unsaturated organic acids containing a hydroxyl group such as hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate or 2-hydroxyoctyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) Acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, cyclobutyl (meth) acrylate, Aliphatic alkyl (meth) acrylates such as cyclohexyl (meth) acrylate and cyclopentyl (meth) acrylate, or phenyl (meth) acrylate, 2- or 4-chlorophenyl (Meth) acrylate, 2- or 4-nitrophenylamino (meth) acrylate, benzyl (meth) acrylate, 2- or 4-chlorobenzyl (meth) acrylate, 2- or 4-nitrobenzyl (meth) acrylate, and 2- Or an aromatic alkyl (meth) acrylate such as 4-dimethylaminophenyl (meth) acrylate is exemplified.

Examples of the unsaturated organic acid ester containing an epoxy or vinyl group include allyl (meth) acrylate, butyl glycidyl (meth) acrylate, and glycidyl (meth) acrylate.

The compound represented by the above formula (1) preferably has a glass transition temperature of from 30 to 120 ° C. and from 1,000 to 120 ° C.
It has a weight average molecular weight of 100,000. If the glass transition temperature is less than 30 ° C., the heat resistance is poor, and
If the temperature exceeds 0 ° C., there arises a problem that the accuracy of the color filter pattern after transfer is reduced. On the other hand, when the weight average molecular weight is out of the above range, heat resistance and transfer characteristics become poor, which is not preferable.

A method for polymerizing the acrylic resin as the above compound will be described.

First, about 90% of the total solvent amount (for example, propylene glycol monomethyl ether acetate: PGMEA) and about 30% of the total monomer amount (methacrylic acid, butyl methacrylate and glycidyl acrylate (especially 40:50:10 molar ratio is preferred))
Are mixed in a polymerization vessel, and then heated to a predetermined temperature, for example, 60 ° C. in a nitrogen atmosphere. On the other hand, one of the two dropping funnels has a predetermined amount based on the total amount of monomers, for example, 2% by weight.
Polymerization initiator (eg, azobisisobutyronitrile)
With the remaining amount of solvent and the other with the remaining amount of monomer. When the temperature of the polymerization vessel reaches 60 ° C., the polymerization initiator and the monomer are slowly dropped from the one dropping funnel into the polymerization vessel for a predetermined time, for example, 1 hour. After the dropwise addition, the mixture is reacted for a predetermined time, for example, 2 hours, and then quenched with hydroquinone. Next, the reaction solution is precipitated in hexane and then purified to obtain a binding resin.

On the other hand, in the coloring composition for forming a color filter according to the present invention, the crosslinking agent is a polyfunctional compound or an oligomer thereof, and specific examples thereof include ethylene glycol, propylene glycol, polyalcohol, and the like. Polyfunctional alcohols such as polyglycols and their oligomers, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate,
1,4-cyclohexanedi (meth) acrylate, trimethylol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, sorbitol tri (meth) acrylate Polyfunctional acrylates such as acrylate, sorbitol tri (meth) acrylate, sorbitol penta (meth) acrylate, sorbitol hexa (meth) acrylate, tetramethylene glycol di (meth) acrylate, and bisphenol A diglycidyl ether;
Allyl glycidyl ether, allyl glycidyl ether, polyalcohol / polyglycol type epoxy resin,
Examples include epoxy group-containing polyfunctional compounds such as glycerin triglycidyl ether resin and oligomers thereof.

As the polymerization initiator, benzoyl peroxide, t-butyl peroxide, t-butyl hydroperoxide, azobisisobutyronitrile and the like are used.

As the color material, CI yellow pigments 20, 2
4, 83, 86, 93, 109, 110, 117, 12
5, 137, 138, 139, 147, 153, 16
6, 168 and CI red pigments 9, 97, 122, 12
3, 149, 168, 177, 180, 192, 21
5, 216, 217, 220, 223, 224, 22
6, 227, 228, 240 and CI blue pigments 15, 1
5: 1, 15: 3, 15: 4, 15: 6, 15: 9, 2
2, 60, 64, CI green pigments 7, 36, or CI purple pigments 19, 23, 29, 30, 37, 40, 5,
A combination of at least two pigments selected from the group consisting of 0 is used. Preferably, the red material is a mixture of CI red pigment 177 and CI yellow pigment 83, and the green material is CI green pigment 36 and CI
From the mixture with the purple pigment 23, as a blue material, C
It is produced from a mixture of 15: 6 I blue pigment and 23 CI purple pigment, respectively.

For dispersing the color material, generally, various dispersing means such as a three-roll mill, a two-roll mill, a sand mill, and a bead mill are used, and a dispersion aid is appropriately added to improve the dispersion. it can. As such a dispersing agent, various surfactants and derivatives such as pigments can be used. These prevent the re-aggregation of the pigment after the dispersion and enable the formation of a color filter having excellent transparency.

As the solvent, a solvent capable of sufficiently dispersing a color material such as a pigment is used. For example, cellosolve acetate, ethyl cellosolve acetate, diethylene glycol dimethyl ether, ethylbenzene, ethylene glycol diethyl ether, xylene, One selected from cyclohexanol, ethyl cellosolve and propylene glycol monomethyl ether acetate is used alone or in combination of two or more.

Further, the coloring composition for forming a color filter according to the present invention comprises a slip agent, a homogenizing agent (l
Eveling agents, sagging agents or defoamers may also be added, which serve to enhance the coating properties of the coloring composition and obtain a good color filter pattern.

A general method for forming a color filter by a laser transfer method using the coloring composition for forming a color filter according to the present invention is as follows.

First, a donor film is prepared. Here, a polyethylene terephthalate film, polycarbonate, or the like is used as the base film. After absorbing light, a black layer (propulsion layer) for releasing nitrogen or hydrogen gas or releasing heat to provide transfer energy is formed on the base film, and then an intermediate layer is formed on the black layer. And a color layer to which a composition for forming a color filter is applied. The intermediate layer is not necessarily formed, but is preferably formed to prevent the subsequent color layer from being contaminated by the black layer and to improve the smoothness of the formed color filter.

The color layer is formed by applying a composition for forming a color filter to a thickness of about 1 to 2 μm. The coating method used at this time includes gravure printing, gravure printing, and the like. Die coating method or bar coating method
ng) and the like, and preferably a die coating method is used.

Next, a donor film is placed on a transparent substrate on which a black matrix is formed, and a color filter is formed by irradiating a laser. Optionally, a pattern is formed in the order of red, green, and blue. Is thermally cured to form a color filter.

In order to obtain a high-precision color filter pattern having a good surface condition, the coloring composition for producing a color filter by the transfer method is deformed or evaporated by heat generated in the propelling layer while maintaining a uniform composition in the transfer process. should not be done. In the present invention, the acrylic resin of the above formula 1 was used as a binder resin, and at least one kind of a crosslinking agent having good compatibility was added to the acrylic resin to prepare a coloring composition. At this time, the acid value of the binder resin is 70 to 13 in view of the adhesiveness to glass.
Those with 0 mg KOH are preferred.

The color filter formed in this way has a lower cost than the color filter formed by the usual method, due to the shortened manufacturing process, and has high precision, high color purity, chemical resistance and Excellent heat resistance.

[0032]

Hereinafter, a method of manufacturing a color filter according to the method of the present invention will be described in more detail with reference to an example of the present invention.

Polymerization of Acrylic Resin Methacrylic acid, butyl methacrylate and glycidyl acrylate (40:50:10 molar ratio) were dissolved in propylene glycol monomethyl ether acetate, and azobisisobutyronitrile was used as a polymerization initiator.
Solution polymerization was performed at 0 ° C. to produce an acrylic copolymer resin.

At this time, the weight average molecular weight of the produced copolymer resin was 30,000 and the glass transition temperature was 80 ° C.

Production of Color Material CI red pigment 177 and CI yellow pigment 83 were used as dispersants and dispersed by a bead mill so as to have a particle diameter of about 0.1 μm. To prepare a red color material. Similarly to this method, the green color material is a mixture of the CI green pigment 36 and the CI yellow pigment 83, and the blue color material is the CI blue pigment 15: 6.
And CI purple pigment 23.

Preparation of Composition for Forming Color Filter As shown in Table 1 below, an acrylic copolymer resin, pentaerythritol triacrylate and propylene glycol (8: 2 weight ratio) were used as a crosslinking agent, and a red A color material and benzoyl peroxide are dissolved in a mixed solvent of propylene monomethyl ether acetate and cyclohexane (weight ratio of 85:15) to obtain a uniform red coloring composition having a total solid content of 20 to 22% by weight of the whole composition. Manufactured.

In place of the red material, a green material and a blue material were used, respectively, to produce corresponding green and blue color materials.

[0038]

[Table 1]

* The above weight percentages are based on the total amount of the composition.

Preparation of Donor Film Polyethylene terephthalate was used as a base film, and a black layer made of a carbon compound and an intermediate layer for protecting a subsequent color layer were sequentially formed on the base film. The colored composition was die-coated to a thickness of about 1.2 μm to prepare a red donor film.

Next, donor films for green and blue were prepared from the green coloring composition and the blue coloring composition, respectively.

Preparation of Color Filter First, the red donor film was placed at a position away from the transparent substrate on which the black matrix was formed, and the color layer was transferred onto the transparent substrate by a laser transfer method.

Next, the donor films for green and blue are also subjected to laser transfer, and all the red, green, and blue patterns are formed on the transparent substrate, and then thermally cured at 230 ° C. in a nitrogen atmosphere to obtain a color. A filter was made.

[0044]

The thermosetting coloring composition for forming a color filter according to the present invention can be used when the color filter is formed by a laser transfer method which has a simpler process than conventional methods and has a good yield.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // C08F 20/40 C08F 20/40 290/12 290/12 C09D 4/00 C09D 4/00 133/06 133/06 133 / 14 133/14

Claims (7)

[Claims] 1. 5 to 50% by weight (based on the total weight)
In the coloring composition for forming a color filter containing the solid content and the remaining amount of the solvent, the solid content is 20 to 60% by weight (each based on the weight of the solid content) of the binding resin represented by the following formula: , 10-40% by weight of crosslinking agent, 0.1-
A thermosetting coloring composition for forming a color filter, comprising 10% by weight of a polymerization initiator, 20 to 60% by weight of a color material, and 0 to 10% by weight of other additives: 1) Wherein R ₁ represents hydrogen or a methyl group; R ₂ represents an alkyl group having 1 to 12 carbon atoms, a hydroxyalkyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aromatic ring group, R ₃ represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group or a benzyl group having 3 to 10 carbon atoms, and X represents hydrogen, a vinyl group or an epoxy group. And 0.1 ≦ a ≦ 0.65, 0.3 ≦ b ≦ 0.8 and 0 ≦ c ≦ 0.2 (where a, b and c are mole fractions) , A + b + c = 1). 2. The bonding resin of the formula 1 is an acrylic resin obtained by polymerizing (meth) acrylic acid, an unsaturated organic acid ester, and an unsaturated organic acid ester containing an epoxy or vinyl group. The thermosetting coloring composition for forming a color filter according to claim 1. 3. The method according to claim 2, wherein the unsaturated organic acid ester is an unsaturated organic acid ester containing a hydroxyl group, an aliphatic alkyl (meth) acrylate, or an aromatic alkyl (meth) acrylate. A thermosetting coloring composition for forming a color filter. 4. The method according to claim 1, wherein the aromatic alkyl (meth) acrylate is phenyl (meth) acrylate, 2- or 4-chlorophenyl (meth) acrylate, 2- or 4-nitrophenylamino (meth) acrylate, benzyl (meth) acrylate, The color filter of claim 3, wherein the color filter is at least one selected from the group consisting of 2- or 4-chlorobenzyl (meth) acrylate and 2- or 4-nitrobenzyl (meth) acrylate. Thermosetting coloring composition. 5. The method according to claim 1, wherein the unsaturated organic acid ester containing an epoxy or vinyl group is at least one selected from the group consisting of allyl (meth) acrylate, butyl glycidyl (meth) acrylate and glycidyl (meth) acrylate. The thermosetting coloring composition for forming a color filter according to claim 2. 6. The thermosetting coloring composition for forming a color filter according to claim 1, wherein a glass transition temperature of the binding resin represented by the formula 1 is 30 to 120 ° C. 7. The thermosetting coloring composition for forming a color filter according to claim 1, wherein the weight average molecular weight of the binding resin represented by Formula 1 is 1,000 to 100,000. Stuff.