JPH11143056A - Material and method for forming black matrix for color liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the material for forming the black matrix high in precision by incorporating an alkali-soluble resin obtained by condensing phenols containing cresol with aldehydes, an acid-cross-linkable methylolated melamine, a specified compound to be allowed to produce an acid by absorbing light, and a black pigment. SOLUTION: The black matrix forming material contains the alkali-soluble resin obtained by condensing phenols containing cresol with aldehydes, the acid-cross-linkable methylolated melamine, the black pigment, and one of the compounds to be allowed to produce an acid by absorbing light and represented by formulae I-II in which each of R1 and R7 is, independently, an H or halogen atom car a hydroxy or 1-3C alkyl or such alkoxy group; each of R5 and R6 is, independently, a 1-3C alkyl group; T is a univalent group represented by formula IV; (m) is 1, 2, or 3; (n) is 1, 2, 3, or 4: and X in formula IV is a halogen atom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a black matrix forming material for a color liquid crystal display and a method for forming a black matrix for a color liquid crystal display using the material.

[0002]

2. Description of the Related Art A color filter of a color liquid crystal display device affects the display quality of the color liquid crystal display device. Above all, in order to increase the aperture ratio and the contrast, it is necessary that the black matrix of the color filter has a sufficient light-shielding property and is formed with high resolution.
Conventionally, a chromium deposition film has been used for a black matrix of a color filter. However, although the black matrix made of a chromium-deposited film has excellent light-shielding properties, it has high reflectivity, which causes reflections and deteriorates visibility. The process of manufacturing a color filter using chrome for the black matrix is complicated and costly. Is a problem,
Further, there is a problem of treating the chromium waste liquid.

[0003] Under these circumstances, a black matrix in which a photosensitive resin coating film in which a black pigment is dispersed has been patterned has been developed, and can be manufactured at low reflection and at low cost. As the photosensitive resin in which the black pigment is dispersed, a radical polymerization type photosensitive resin is used. However, since the radical polymerization type photosensitive resin is cured only to a portion where light can reach, curing is insufficient near an interface between the coating film and the substrate, and an allowable range of development conditions is narrow. In addition, the photosensitive resin in which a black pigment and a quinonediazide compound are combined, the components are simply mixed, applied, and subjected to operations such as drying, and alkali insolubles are generated to lower the image contrast. There is a problem that the developer becomes substantially insoluble and pattern formation cannot be performed at all.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a black matrix forming material for a color liquid crystal display device in which the curing reaction proceeds sufficiently to the substrate interface even if the concentration of the black pigment is high, and the development tolerance is wide. Is to provide. Another object of the present invention is that the curing reaction does not proceed only by the steps of mixing, coating, and drying the components constituting the black matrix forming material, and the exposed part and the unexposed part have a sufficiently high solubility contrast with the developing solution, and a high definition. An object of the present invention is to provide a black matrix forming material for a color liquid crystal display device which provides a suitable black matrix. It is still another object of the present invention to provide a method for forming a high density, high definition black matrix for a color liquid crystal display device.

[0005]

According to the present invention, there are provided a black matrix forming material for a color liquid crystal display device of the following [1] and [2] and a method for forming a plaque matrix for a color liquid crystal display device using the same. Thus, the object of the present invention is achieved. [1] (A) an alkali-soluble resin obtained by condensing phenols and aldehydes containing at least cresol, (B) an acid-crosslinkable methylolated melamine resin, (C)
The following general formulas (I) to (III) which generate an acid by absorbing light
A black matrix-forming material for a color liquid crystal display device, comprising: (D) a black pigment.

[0006]

Embedded image

(In the above formula, R₁, R₇Are each independently
Hydrogen atom, hydroxyl group, halogen atom, carbon number 1
3 represents an alkyl group or an alkoxy group having 1 to 3 carbon atoms.
Then R _FiveAnd R₆Are the same or different and have 1 to 3 carbon atoms
Represents an alkyl group, and T is represented by the following general formula (IV)
Represents a monovalent group, m is an integer of 1 to 3, and n is 1 to 4
Is an integer.

[0008]

Embedded image

In the general formula (IV), X represents a halogen atom. [2] The material for forming a black matrix for a color liquid crystal display device according to [1] is applied to a transparent substrate, and the formed coating film is exposed to a desired pattern. A method for forming a black matrix for a color liquid crystal display device, comprising crosslinking and diffusing an acid generated by exposure to a substrate, and removing an unexposed portion with an alkali developing solution.

The black matrix forming material of the above specific composition of the present invention is coated on a substrate, and the formed coating film is exposed to a desired pattern, whereby the component (C) present in the exposed portion is decomposed. To generate acid. The acid generated by the subsequent heat treatment crosslinks the acid-crosslinkable methylolated melamine resin, which is the component (B), and is insolubilized in an alkali developing solution. At the same time, the acid generated by exposure diffuses to the substrate. The component (B) in the vicinity can also be crosslinked and insolubilized.

According to the present invention, even if the light is blocked by the black pigment and does not reach the interface between the substrate and the coating film,
By simply exposing the surface of the coating film, the component (B) is cross-linked to the interface between the substrate and the coating film and can be insolubilized in a developer. As a result, a black matrix containing a high concentration of a black pigment is formed. In addition, components (A) to
(D) may be subjected to a series of steps of mixing, coating and drying,
There is no curing, and the contrast of solubility between the exposed part and the unexposed part in the developing solution is sufficiently large. Therefore, the formed black matrix has high definition. The present invention is described in detail below, and other objects, advantages and effects of the present invention will become apparent.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an alkali-soluble resin obtained by condensing a phenol and an aldehyde containing at least cresol, which is a component of a black matrix forming material for a color liquid crystal display device, will be described. In the present invention, the resin is preferably a resol resin or a novolak resin obtained by condensing a phenol containing at least cresol and an aldehyde. As the alkali-soluble resin obtained by condensing a phenol containing at least cresol and an aldehyde, a resin obtained by reacting a phenol containing at least 50% of o-, m- or p-cresol with an aldehyde is preferable. . Examples of phenols that may be contained in addition to cresol include o-methoxyphenol, m-methoxyphenol, o-ethylphenol, m-ethylphenol, p-ethylphenol, 3,5-dimethoxyphenol, and 2-methoxy-4. -Methylphenol,
o-propoxyphenol, o-butoxyphenol,
Examples include 3,4,5-trimethylphenol, o-vinylphenol, m-phenylphenol and the like.

The aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde and the like. Preferably it is formaldehyde. In the present invention, a resin obtained by reacting o-, m- or p-cresol or a mixture thereof with formaldehyde is preferred.

The weight average molecular weight of the above resin is preferably 500 to 20,000, more preferably 10 to 20,000.
00 to 15000.

The content of the resin of the above-mentioned component (A) in the forming material of the present invention is from 35 to 35% based on the total solid content (weight).
It is preferably 90% by weight, more preferably 45 to 75% by weight.

The (B) acid-crosslinkable methylolated melamine resin, which is a component of the black matrix forming material for a color liquid crystal display device, will be described. As the acid-crosslinkable methylolated melamine resin, specifically, monomethylol melamine, dimethylol melamine, trimethylol melamine,
Examples include tetramethylolmelamine, pentamethylolmelamine, and hexamethylolmelamine. A preferred embodiment according to the present invention is hexamethylolmelamine.

The content of the acid-crosslinkable methylolated melamine resin (B) in the forming material of the present invention is preferably from 0.1 to 30% by weight, more preferably from the total solid content (weight). Is 1 to 10% by weight.

The halogen-containing triazine compounds represented by the above general formulas (I) to (III), which are components of the black matrix forming material of the present invention and which generate an acid by absorbing light (C), will be described.

In the general formulas (I) to (III), R ₁ , R
₇ represents a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. Among them, a hydroxyl group, a halogen atom and an alkoxy group having 1 to 3 carbon atoms are preferable. R ₅ and R
₆ is the same or different and represents an alkyl group having 1 to 3 carbon atoms. Preferred alkyl groups are ethyl group, propyl group,
It is an isopropyl group. T represents a monovalent group represented by the general formula (IV), and m is an integer of 1 to 3, preferably 1
And n is an integer of 1 to 4, preferably 1 or 2. In the general formula (IV), X represents a halogen atom, preferably a bromine atom or a chlorine atom.

Preferred specific examples of the halogen-containing triazine compounds represented by the general formulas (I) to (III) include the following compounds.

4- (o-fluoro-p-N-chloroethylaminophenyl) -2,6-di (trichloromethyl)-
s-triazine, 4- (o-chloro-p-N-chloroethylaminophenyl) -2,6-di (trichloromethyl) -s-triazine, 4- (o-bromo-p-N-chloroethylaminophenyl ) -2,6-di (trichloromethyl) -s-triazine, 4- (m-fluoro-p-N
-Chloroethylaminophenyl) -2,6-di (trichloromethyl) -s-triazine, 4- (m-chloro-p
-N-chloroethylaminophenyl) -2,6-di (trichloromethyl) -s-triazine, 4- (o-fluoro-p-N-methoxycarbonylmethylaminophenyl)
-2,6-di (trichloromethyl) -s-triazine,
4- (o-chloro-p-N-methoxycarbonylmethylaminophenyl) -2,6-di (trichloromethyl)-
s-triazine and the like.

Among them, 4- (o-fluoro-p-N-ethoxycarbonylmethylaminophenyl) -2,6-di (trichloromethyl) -s-triazine, 4- (o-bromo-p-N-ethoxy) Carbonylmethylaminophenyl) -2,6-di (trichloromethyl) -s-triazine, 4- (o-chloro-p-N-ethoxycarbonylmethylaminophenyl) -2,6-di (trichloromethyl) -s- The use of triazines is preferred. The halogen-containing triazine compounds as described above can be used alone or in combination of two or more. The compounding amount of the halogen-containing triazine compound in the forming material of the present invention is preferably 0.1 to 3 with respect to the total solid content (weight).
0% by weight, more preferably 1 to 10% by weight.

As the (D) black pigment used in the black matrix forming material of the present invention, any of organic pigments and inorganic pigments can be used. As preferred organic pigments, phthalocyanine pigments exemplified by phthalocyanine blue and phthalocyanine green; anthraquinone pigments exemplified by chromophthal red; azo or azo lake pigments exemplified by Bordeaux 10B and lake red; Isoindolinone pigments; dioxazine pigments exemplified by dioxazine violet; nitroso pigments exemplified by naphthol green B; nitro pigments; lake pigments exemplified by peacock blue lake and rhodamine lake; quinacdrine pigments; Having high heat resistance and light resistance. Preferred inorganic pigments include carbon black; metal oxide pigments such as titanium oxide, iron oxide, zinc oxide, and chromium oxide; sulfide pigments exemplified by zinc sulfide; and other carbonates and silicates. These pigments are used singly or in combination of two or more, depending on the type. These pigments are preferably used in an amount of 10 to 70% by weight, particularly 20 to 50% by weight, based on the total solid content (weight).

Regardless of the type of pigment used, in order to avoid light scattering and ensure flatness, the particle size is 0.4 μm.
m or less, particularly preferably 0.2 μm or less.

In order to increase the darkness, the transmittance is uniformly set to 5% or less over the entire visible light range, and the transmittance at around 550 nm, at which the human eye is most sensitive, is minimized. It is preferable to select the ratio of the amount of the pigment used.

The above (A), (B), (C) and (D)
In addition to the components described above, the black matrix forming material for a color liquid crystal display device of the present invention may include, as an optional component, a silicon-based surfactant, a fluorine-based surfactant, and an amine as long as the object of the invention is not hindered. And the like.

From the black matrix forming material of the present invention, a black matrix of a color liquid crystal display device can be formed by the following method. That is, it contains (A) an alkali-soluble resin, (B) an acid-crosslinkable methylolated melamine resin, (C) a halogen-containing triazine compound capable of absorbing light to generate an acid, (D) a black pigment, and an optional component. A resist made of a black matrix forming material is applied to a transparent substrate, and the solvent is dried by heating to form a black resist film. Subsequently, the black resist film is selectively exposed using a mask having a desired pattern.
By this exposure, in the exposed portion of the resist surface, the component (C) is decomposed by the action of light to generate an acid. By the heat treatment, the acid reacts with the component (B),
Simultaneously with the crosslinking of the component (B), the acid diffuses in the thickness direction of the black resist film, and the crosslinking of the component (B) further proceeds to the vicinity of the substrate, thereby forming a latent image. Thereafter, development processing is performed with an alkali developing solution, and the unexposed portions are removed, and a black resist pattern is selectively formed on the transparent substrate. Further, by performing post-baking, a black matrix is formed.

Here, the thickness of the coating film is set to 0.1.
5 to 5 μm is preferable, and more preferably 0.7 to 3 μm
It is. Examples of the exposure light include ultraviolet rays, electron beams, X-rays, and the like. As the above-mentioned heat treatment, a preferable temperature is 80 to 180 ° C, more preferably 100 to 160 ° C.
The heating can be performed at a preferable heating time of 30 seconds to 300 seconds, more preferably 30 seconds to 180 seconds. As the alkali developer, those commonly used in this field can be used. For example, inorganic alkalis such as potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, potassium hydrogen carbonate, sodium hydrogen carbonate, etc., or triethanolamine, trimethylamine, triethylamine, pyridine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, etc. Amines can be mentioned.

As described above, by using the black matrix forming material of the present invention as a resist, an acid is generated by exposure, and the resist is not directly cured by light. Thereafter, the heat treatment allows a cross-linking reaction to occur selectively in the portion where the acid has been generated, and at the same time, the acid can be diffused in the film thickness direction by heating to advance the curing of the resist. Thereby, the development latitude is widened, and a black matrix having a high optical density is formed.

[0030]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. (Example 1) First, a solution having the following composition was prepared and stirred for 8 hours to obtain a photosensitive resin solution. Resole (* 1) 5 g Hexamethylolmelamine 0.5 g 4- (O-bromo-p-N-ethoxycarbonylmethylaminophenyl) -2,6-di- (trichloromethyl) -s-triazine 0.55 g Carbon black dispersion Liquid (* 2) 22 g Ethyl cellosolve acetate 40 g (* 1: resole resin consisting of o-cresol, p-cresol and formaldehyde) (* 2: propylene glycol monomethyl ether acetate solution with a solid concentration of 33%)

Using a spin coater, the photosensitive resin solution was cut into 1.1 mm thick borosilicate glass 7059 manufactured by Corning Co., Ltd. in a 100 mm square, and ultrasonically washed with a 1% aqueous sodium hydroxide solution using a spin coater. It was applied to a thickness of 0.1 μm and heated at 100 ° C. for 60 seconds. Then, exposure was performed at 200 mJ / cm ^{2 using} an exposure apparatus manufactured by Ushio Electric Co., Ltd. through a mask having a line width of 20 μm (a portion serving as a black matrix was 20 μm). After heating the substrate at 130 ° C. for 60 seconds, it was immersed in a developing solution FHD-5 manufactured by Fuji Film Aurin Co., Ltd., and then developed by washing with high-pressure spray. Table 1 shows the line width change of the image formed at different times of immersion in the developer.

The obtained black matrix image was converted to 22
After a heat treatment at 0 ° C. for 30 minutes, the film thickness and optical density (OD) were measured.
3.15. The image was well resolved, and no development residue, residue, or chipped image portion occurred. Table 1 also shows the results of changes in line width when the same heating and developing operations were performed with the exposure amount set to 400 mJ / cm ² . Also in this case, the image was well resolved, and no undeveloped portion, no residue, lack of image area, or the like occurred.

(Example 2) A solution having the following composition was prepared and stirred for 8 hours in the same manner as in Example 1 to obtain a photosensitive resin solution. Cresol novolak (* 1) 2.5 g Hexamethylolmelamine 0.3 g 4- (O-bromo-p-N-ethoxycarbonylmethylaminophenyl) -2,6-di- (trichloromethyl) -s-triazine 0.3 g Carbon black dispersion (* 2) 13.5 g propylene glycol monomethyl ether acetate 20 g (* 1: cresol novolak resin composed of o-cresol, p-cresol and formaldehyde) (* 2: propylene glycol monomethyl ether acetate having a solid content of 33%) solution)

This photosensitive resin solution was applied on a glass substrate to a thickness of 1.2 μm in the same manner as in Example 1, and heated at 120 ° C. for 60 seconds. Then, exposure was performed under the condition of 200 mJ / cm ^{2 using} an exposure apparatus manufactured by Ushio Inc. through the same mask as used in Example 1. After heating this substrate at 130 ° C. for 60 seconds, it was similarly immersed in a developing solution FHD-5 manufactured by Fuji Film Aurin, and then washed with high-pressure spray. The line width change when the developer immersion time was changed is as shown in Table 1. When the obtained image was subjected to a heat treatment at 200 ° C. for 20 minutes, the film thickness and the optical density (OD) were 1.15 μm each.
m, OD 3.36. The image is similar to the actual gutter example 1.
The resolution was good, and no development residue, residue, chipping of the image area, etc. were observed.

Comparative Example 1 A solution having the following composition was prepared, and 8
After stirring for an hour, a resin solution was obtained. The above cresol novolak 5 g Hexamethylol melamine 0.5 g 2,3,4,4-tetrahydroxybenzophenone 4-naphthoquinonediazidosulfonic acid ester 0.55 g Carbon black dispersion ^* 13.5 g Propylene glycol monomethyl ether acetate 20 g (*: solid (Protein glycol monomethyl ether acetate solution with a partial concentration of 33%) This resin solution was applied and heated in the same manner as in Example 1 so as to have a film thickness of 1.1 μm. Then 200
After exposure at mJ / cm ² and heating at 120 ° C. for 60 seconds, development was performed. Even when the development time was 4 minutes, the coating film did not change at all, and no image could be obtained. .

Comparative Example 2 In Comparative Example 1, 2, 3, 4, 4
-Tetrahydroxybenzophenone The same operation as in Comparative Example 1 was carried out except that the resin solution was prepared by changing 4-naphthoquinonediazidosulfonic acid ester to 2,4-trichloromethyl (4'-methoxystyryl) -6-triazine. went. After exposure, heating and development, all of the image was dissolved in the developer without leaving any image. In addition, the heating conditions after exposure,
Assuming 140 ° C. and 60 seconds, the image is lμm with a line width of 20 μm.
ine & space was not resolved, and it became a solid image with space collapsed.

(Comparative Example 3) A solution having the following composition was prepared, and
After stirring for an hour, a resin solution was obtained. Diventerythritol hexaacrylate 5 g Acrylic resin ^** 6 g 2,4-Trichloromethyl (4'-dimethylaminostyryl) -6-triazine 0.55 g Carbon black dispersion ^* 25 g Ethyl cellosolve acetate 40 g (*: solids concentration 33 % Propylene glycol monomethyl ether acetate solution, **: hydroxyethyl methacrylate / styrene / methacrylic acid copolymer)

This resin solution was applied and heated in the same manner as in Example 1 to a thickness of 1.0 μm. Next, after performing exposure of 400 mJ / cm ² , the same developing processing as in Example 1 was performed using a developing solution CD20001 manufactured by Fuji Film Ohlin Co., Ltd. Table 2 shows changes in the line width of the image formed at different times of immersion in the developer. The obtained black matrix image was heated at 200 ° C.
For 20 minutes, and then the film thickness and optical density (OD) were measured.
It was 5.

[0039]

[Table 1]

[0040]

[Table 2]

From the above Examples and Comparative Examples, the black matrix forming material of the present invention has a wide allowable range of development after exposure, and has a sufficiently high contrast between the exposed and unexposed portions in the developing solution. It can be seen that a fine black matrix can be obtained at a high concentration.

[0042]

The black matrix forming material for a color liquid crystal display device of the present invention comprises: Even if the black pigment is at a high concentration, the curing reaction sufficiently proceeds to the substrate interface; 2. The development tolerance is wide. The curing reaction does not proceed only by the mixing, coating, and drying steps of the components, and the contrast of solubility between the exposed portion and the unexposed portion in the developing solution is sufficiently large. Therefore, from the black matrix forming material of the present invention,
A high concentration, high definition black matrix can be obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G02B 5/00 G02B 5/00 B 5/20 101 5/20 101 G02F 1/1335 G02F 1/1335 G03F 7/027 511 G03F 7 / 027 511 7/038 601 7/038 601

Claims (2)

[Claims] 1. An alkali-soluble resin obtained by condensing a phenol containing at least cresol and an aldehyde, (B) an acid-crosslinkable methylolated melamine resin,
(C) The following general formulas (I) to which generate an acid by absorbing light.
At least one selected from the group of compounds represented by (III)
A black matrix forming material for a color liquid crystal display device, comprising: a seed; and (D) a black pigment. Embedded image (In the above formula, R ₁ and R ₇ each independently represent a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and R ₅ and R ₆ Is the same or different and represents an alkyl group having 1 to 3 carbon atoms, T represents a monovalent group represented by the following general formula (IV), m is an integer of 1 to 3, and n is 1 It is an integer of up to 4. In the general formula (IV), X represents a halogen atom. ) 2. A material for forming a black matrix for a color liquid crystal display device according to claim 1, which is applied to a transparent substrate, the formed coating film is exposed in a desired pattern, and after the exposure, heat treatment is performed to form an exposed portion. A method for forming a black matrix for a color liquid crystal display device, comprising crosslinking and diffusing an acid generated by exposure to a substrate, and removing an unexposed portion with an alkali developing solution.