JPH08286026A - Black matrix substrate and color filter using the same - Google Patents

Abstract

PURPOSE: To obtain a black matrix substrate free from plating other than a pattern line part and defect with a simple method by containing a specific organic metal complex in a black dispersing resin. CONSTITUTION: A black composition is obtained by adding palladium acetate of the organic metal complex into a black dispersed body prepared by adding carbon black and a dispersing agent in a polyimide resin. A metal of the organic metal complex is a metal the same as or more noble than that of a metallic layer. A black resin layer 2 composed of the black composition is formed on a transparent glass substrate 1. A positive photoresist is applied thereon by spin coating, exposed with a prescribed mask, developed and the black resin layer 2 is etched. A resin black pattern 4 is formed by stripping the possitive photoresist pattern 3. The substrate is dipped into an electroless nickel plating solution to form a metal nickel layer 5 on the resin black pattern 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter used in a liquid crystal color display or the like, and more particularly to a black matrix substrate having a colored pattern formed on a transparent substrate and a black matrix as a light shielding layer between the colored patterns, and a color filter using the same. Regarding

[0002]

2. Description of the Related Art Conventionally, as a method of manufacturing a black matrix for a color filter, a metal chromium thin film is formed by means such as sputtering, and the metal chromium thin film is patterned by a photolithography technique using a positive resist. The method was common. However, the black matrix obtained in this way has a high reflectance, which lowers the display quality of the panel, requires a vacuum film forming process, and thus has a high manufacturing cost. Was desired.

Therefore, as a production method for replacing metal chromium, a method for producing a black matrix using a metal film formed by electroless plating has been proposed in recent years. Of these, the method by electroless plating of nickel is the most promising and is being studied. (JP-A-62-17890
No. 5, JP-A-4-90501, etc.)

An example of a method of manufacturing a black matrix composed of two layers of a resin black pattern and a metallic nickel layer will be described below. First, a black resin layer containing a light-shielding pigment such as carbon black is formed on a transparent substrate and processed into a desired pattern (resin black pattern) using a photolithography technique such as an etching method. (A photosensitive material may be used for the resin.) Next, this is immersed in a reducing solution containing a tin salt as a main component, and tin salt is applied onto the resin black pattern (sensitizer treatment). Then, it is immersed in a catalyst solution containing palladium chloride as the main component to deposit (activator) metallic palladium, which serves as a plating catalyst, on the surface of the resin black pattern, and then immersed in an electroless nickel plating solution to form a resin black pattern. A metal nickel film is selectively formed to manufacture a black matrix composed of two layers of a resin black pattern and a metal nickel layer. According to this method, since the resin black pattern is formed on the transparent substrate side, the reflectance when viewed from the panel surface is low, the display quality is not deteriorated, and the black matrix is manufactured at a relatively low cost. It is possible.

However, in this method, the tin salt should be applied and the metal palladium should be selectively deposited only on the resin black pattern, but the tin salt adheres to the minute irregularities on the resin black surface. However, the metal nickel film is easily removed in a cleaning process and the like, and unevenness of the metal nickel film is likely to occur. Also, if there is contamination in the non-image area,
For example, when patterning resin black, if there is a small amount of resin black remaining outside the image area, or if hydrophilic stains adhere during the process, metallic palladium also deposits on that part and nickel is plated. Becomes a defect. The remaining generation and contamination of the substrate can be suppressed to some extent during the process, but it is difficult to completely remove it, and an extra process is required, which is a manufacturing disadvantage.

Various studies have been carried out to improve this point, and the amount of acrylic resin solid content in the resin black is 5%.
A method has been proposed in which 10% of palladium chloride is added in advance, the resin black containing the palladium chloride is patterned, and then electroless nickel plating is performed. According to this method, metallic palladium, which serves as a catalyst for electroless nickel plating, is unlikely to deposit on the non-image area of the resin black pattern.

However, since palladium chloride does not dissolve in the diluting solvent of the acrylic resin and exists as coarse particles in the resin pattern, the palladium chloride particles become protrusions in the resin black pattern and cause defects. Further, there is a problem that the deposition of metallic palladium is large and a uniform nickel film cannot be obtained.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a subject of the invention is a black matrix substrate using an electroless plating method. It is an object of the present invention to provide a black matrix substrate which does not have plating adhered to other parts and which can be obtained by a simple method and a color filter using the same.

[0009]

In order to solve this problem, the present invention provides a black pattern in which a resin black pattern made of a black dispersion resin is formed on a transparent substrate and a metal layer is formed thereon by electroless plating. In the matrix substrate,
A black matrix substrate, characterized in that the black dispersion resin contains an organometallic complex of a metal of the metal layer or an organometallic complex of a metal nobler than the metal, and in particular, the metal. The metal of the layer is nickel, the metal of the organometallic complex is any one of nickel, palladium, platinum, silver, copper, and gold, and the content of the organometallic complex is 0. 1-20%
The present invention also provides a black matrix substrate, and a color filter characterized in that a colored pattern having a required number of colors is formed on the black matrix substrate.

The present invention will be described in detail below. As the black dispersion resin according to the present invention, a resin composed of a light-shielding material, a binder resin, a diluting solvent and an organic metal complex is used.

As the light-shielding pigment, carbon black,
Inorganic pigments such as graphite, titanium oxide, chromium oxide, tin oxide and bismuth oxide are used, and it is also possible to mix organic pigments such as blue, yellow and violet for blackening.

As the binder resin, acrylic resin,
A polyimide resin, an epoxy resin, a novolac resin, or the like can be used. As the acrylic resin, acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, cyclic acrylate or methacrylate, hydroxyethyl acrylate or methacrylate, etc. are used, and a molecular weight of about 5,000 to 100,000 is obtained by using about 3 to 5 kinds of these monomers. A synthetic resin is used.

The organometallic complex which is the main feature of the present invention includes tetracarbonylnickel, dicarbonylbis (triphenylphosphine) nickel, dimethylbis (trimethylphosphine) nickel, tetrakis (triphenylphosphine) nickel and the like. ,
Organic palladium complexes such as palladium acetate, dichlorobis (benzonitrile) palladium, dichlorobis (trialkylphosphine) palladium, dichlorobis (tributylphosphine) platinum, tetrakis (triphenylphosphine) platinum, tris (triphenylphosphine) platinum, tetrakis (triphenyl) An organometallic complex of the metal of the metal layer that is an autocatalyst such as an organoplatinum complex such as phosphite) platinum, carbonyltris (triphenylphosphine) platinum, and bis (triphenylphosphine) (acetylene) platinum, or is more noble than the metal Organometallic complexes of metals are used.

A diluting solvent is added to the light-shielding pigment, the acrylic resin, and the organometallic complex, and the mixture is thoroughly kneaded to form a black dispersion.
At this time, if the content of the organometallic complex is less than 0.1% of the total solid content, the concentration of the catalyst metal is insufficient and the plating property is poor.
If it exceeds%, the patternability of the resin black will be impaired. More preferably, when it is 5 to 10%, good plating property is obtained.

As the diluting solvent, cyclohexanone, ethyl cellosolve, butyl cellosolve, methyl cellosolve,
Ethyl cellosolve acetate, butyl cellosolve acetate, methyl ethyl ketone, ethanol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, 2-heptanone, 4-heptanone, lactate esters, pentyl acetate, isopentyl acetate, diglyme, cumene, xylene, ethylbenzene and the like are used. To be

The black dispersion thus obtained is uniformly applied onto a transparent substrate by various coating methods such as spin coating, roll coating and bar coating, or various printing methods such as screen printing and flexographic printing and dried. . As a method for processing this black dispersion layer into a desired pattern, patterning may be performed by a photolithography process using a positive resist, and a photopolymerizable monomer and a photopolymerization initiator may be added to the black dispersion. It is also possible to impart photosensitivity by exposure, and after coating and drying, expose through a photomask and remove the unexposed portion by development to obtain a required pattern.

Examples of the photopolymerizable monomer include difunctional monomers such as 1,6-hexanediol diacrylate, ethylene glycol diacrylate, neopentyl glycol diacrylate, and triethylene glycol diacrylate, trimethylolpropane triacrylate, penta. Trifunctional monomers such as erythritol triacrylate and tris (2-hydroxyethyl) isocyanate, and polyfunctional monomers such as ditrimethylolpropane tetraacrylate, dipentaerythritol penta and hexaacrylate are used.

As the photopolymerization initiator, Michler's ketone, acetophenone, benzophenone benzyl dimethyl ketal, benzoyl peroxide, diethylaminobenzophenone, and other benzophenone compounds, 2- (2,3,3)
-Dichlorophenyl) -4,5-diphenyl-imidazole dimer, 2- (2,3-dichlorophenyl) -4,
Imidazole compounds such as 5-di (2-furyl) -imidazole, 2,2'-bis (2-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1-2'-biimidazole, 2 4,6-Tris (trichloromethyl)-
S-triazine, 2- (p-methoxystyryl) 4,6
-Bis (trichloromethyl) -S-triazine, 2-phenyl-4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -S- Triazine, 2- (p-chlorophenyl) 4,6-bis (trichloromethyl) -S
-Triazine compounds such as triazine, 2- (4'-methoxy-1'-naphthyl) -4,6-bis (trichloromethyl) -S-triazine can be used.

The resin black pattern containing the organometallic complex thus obtained is immersed in an electroless plating solution containing a reducing composition to selectively form a metal film on the resin black pattern.

The reducing composition used here is selected according to the metal to be plated, and is hypophosphorous acid, sodium hypophosphite, sodium borohydride, potassium borohydride, N-dimethylamine borane, borazine. Derivatives, hydrazine, formalin and the like are used.

The electroless plating solution includes the reducing composition, a water-soluble metal salt, a pH adjusting agent such as a basic compound, an inorganic acid or an organic acid, and an alkali such as oxycarboxylic acid, boric acid or carbonic acid. What consists of salt and an aqueous solution of a complexing agent, a stabilizer, a surfactant, etc. is used.

Of these, the metal of the water-soluble metal salt is the metal to be plated, and generally, sulfuric acid such as nickel, copper, cobalt, tin, and hydrochlorides are used.

As described above, the black matrix composed of the two layers of the resin black pattern and the metal layer is formed.

Further, a color filter having excellent display characteristics can be obtained by providing the R, G, B colored patterns on the substrate on which the black matrix is formed by a conventional method.

[0025]

According to the present invention, the metal to be plated or the metal nobler than the metal to be plated, which serves as a catalyst for electroless plating, is deposited only on the pattern of the resin black. It is possible to manufacture a black matrix that is not plated and has no defects. Further, since the sensitizer process and the activator process are unnecessary, it is advantageous in terms of the number of steps. Further, the organometallic complex used in the present invention, unlike the salt, is easily dissolved in the above-mentioned diluting solvent by selecting the group, so that the catalyst metal is uniformly deposited on the surface of the resin black pattern, It is possible to form a uniform metal film.

As a result, it becomes possible to manufacture a black matrix having a low reflectance, few protrusion-like defects, and no plating adhered to the non-image area in a simple process. Moreover, on the substrate on which this black matrix is formed,
By forming a coloring pattern with the required number of colors,
It is possible to obtain a color filter having excellent display quality.

[0027]

【Example】

<Embodiment 1> This will be described with reference to FIG. To 90.1 g of diluted resin obtained by diluting a polyimide resin with n-methylpyrrolidone to a solid content of 10%, 9.0 g of carbon black and 0.9 g of a dispersant were added and kneaded sufficiently with a three-roll mill. A black dispersion was obtained. This black dispersion 9
1.0 g of an organometallic complex, palladium acetate, was added to 9.0 g and completely dissolved to obtain a black composition containing the organometallic complex.

The black composition was spin-coated (2000 rpm, 40 seconds) on a transparent glass substrate 1 and dried to obtain a black resin layer 2. After prebaking at 90 ° C. for 20 minutes, a positive resist (manufactured by Tokyo Ohka Co., Ltd .: “OFPR-
2 ") is spin-coated at 2000 rpm for 30 seconds, and
It was dried by heating at 0 ° C. for 30 minutes. Next, it is exposed (30 mJ / cm ² ) using a predetermined mask with an ultra-high pressure mercury lamp.
Then, the positive resist was developed with a 0.2% aqueous solution of TMAH (tetramethylammonium hydride), and the black resin layer was etched. Then, only the positive resist pattern 3 was peeled off using dimethyl sulfoxide to obtain a resin black pattern 4.

The substrate on which the resin black pattern 4 was formed was used as an electroless nickel plating solution "Top Chemialoy B-1" (manufactured by Okuno Chemical Industries Co., Ltd.) containing a boron compound as a reducing agent and having a solution temperature of 60 ° C. It was dipped for 60 seconds to form the metallic nickel layer 5 only on the resin black layer. Then, it was washed with running water and heated at 230 ° C. for 60 minutes to obtain a black matrix composed of two layers of a resin black pattern and a metallic nickel layer. At this time, no adhesion of plating was observed on the non-image area of the black matrix. The resin black pattern has a thickness of 0.13 μm, and the metallic nickel layer has a thickness of 0.14 μm.
m, and the total was 0.27 μm. The optical density was 4 or more. The reflectance when viewed from the panel surface side was 2% or less.

Further, on the thus obtained black matrix substrate, Red, Green and Blu were formed by a conventional method.
When the colored pattern of e was formed at a predetermined position, the step due to the overlap between the black matrix and the colored pattern was small (0.2 μm), and a color filter with good visibility when viewed from the panel surface was obtained. .

<Second Embodiment> An explanation will be given based on FIG. Acrylic resin (Acrylic resin obtained by dissolving 25 parts of methacrylic acid, 15 parts of methyl methacrylate, 60 parts of butyl methacrylate in 300 g of ethyl cellosolve, adding 0.75 parts of azobisisobutylnitrile under a nitrogen atmosphere and reacting at 70 ° C. for 5 hours ) Was diluted with ethyl cellosolve to a resin concentration of 10%. To 90.1 g of this diluted resin, 9.0 g of carbon black and 0.9 g of a dispersant were added and sufficiently kneaded with a three-roll mill to obtain a black dispersion.
To 99.0 g of this black dispersion, 1.0 g of tetrakis (triphenylphosphite) platinum, which is an organometallic complex, was added and completely dissolved.

To 100 g of this black resin, 0.4 g of trimethylolpropane triacrylate (monomer),
Photopolymerization initiator Michler's ketone 0.02 g, 2- (2,3
0.01 g of -dichlorophenyl) -4,5-diphenyl-imidazole dimer was added and well stirred to obtain a photosensitive black composition.

The photosensitive black composition was spin-coated (2000 rpm, 40 seconds) on the transparent glass substrate 1 and dried to obtain a black resin layer 2. This was prebaked at 70 ° C. for 20 minutes and then coated with a 5% solution of polyvinyl alcohol to form an oxygen barrier film 6. After further drying at 70 ° C. for 20 minutes, it was exposed (15 mJ / cm ² ) using a predetermined mask. Then, it was developed with a 2.5% aqueous sodium carbonate solution and thoroughly washed with water to obtain a resin black pattern 4.

The substrate on which the resin black pattern 4 is formed has a liquid temperature of 60 ° C. containing a boron compound as a reducing agent.
Electroless nickel plating solution "Top Chemialoy B-1"
(Okuno Pharmaceutical Co., Ltd.) was immersed for 60 seconds to form the metallic nickel layer 5 only on the resin black pattern.
Then, it was washed with running water and heated at 230 ° C. for 60 minutes to obtain a black matrix composed of two layers of a resin black pattern and a metallic nickel layer. At this time, no adhesion of plating was observed on the non-image area of the black matrix. The resin black pattern had a thickness of 0.13 μm, the metal nickel layer had a thickness of 0.14 μm, and the total thickness was 0.27 μm. The optical density was 4 or more. The reflectance when viewed from the panel surface side was 2% or less.

Further, on the black matrix substrate thus obtained, Red, Green, and Blu were formed by a conventional method.
When the coloring pattern of e was formed at a predetermined position, the step due to the overlap between the black matrix and the coloring pattern was small (0.2 μm), and a color filter with good visibility when viewed from the panel surface was obtained. .

<Comparative Example> A description will be given with reference to FIG. Acrylic resin (Acrylic resin obtained by dissolving 25 parts of methacrylic acid, 15 parts of methyl methacrylate and 60 parts of butyl methacrylate in 300 g of ethyl cellosolve and adding 0.75 parts of azobisisobutylnitrile in a nitrogen atmosphere and reacting at 70 ° C for 5 hours ) Was diluted with ethyl cellosolve to a resin concentration of 10%. To 90.1 g of this diluted resin, 9.0 g of carbon black and 0.9 g of a dispersant were added and sufficiently kneaded with a three-roll mill to obtain a black dispersion. To 99.0 g of this black dispersion was added palladium chloride 1.0
Although g was added and the mixture was sufficiently stirred, palladium chloride was not dissolved in the solvent and was present as particles in the black dispersion.

To 100 g of this black resin, 0.4 g of trimethylolpropane triacrylate (monomer),
Photopolymerization initiator Michler's ketone 0.02 g, 2- (2,3
0.01 g of -dichlorophenyl) -4,5-diphenyl-imidazole dimer was added and well stirred to obtain a photosensitive black composition.

On the transparent glass substrate 1, a blue photosensitive black composition was spin-coated (2000 rpm, 40 seconds),
It was dried to obtain a black resin layer 2. This was prebaked at 70 ° C. for 20 minutes and then coated with a 5% solution of polyvinyl alcohol to form an oxygen barrier film 6. After further drying at 70 ° C. for 20 minutes, it was exposed (15 mJ / cm ² ) using a predetermined mask. After development with a 2.5% aqueous sodium carbonate solution, the product was thoroughly washed with water to obtain a resin black pattern 4. The substrate on which the resin black pattern 4 is formed is immersed for 60 seconds in an electroless nickel plating solution "Top Chemialoy B-1" (manufactured by Okuno Chemical Industries Co., Ltd.) containing a boron compound as a reducing agent and having a solution temperature of 60 ° C. Then, the metallic nickel layer 8 was formed only on the resin black pattern. Then, wash with running water and 6 at 230 ℃.
It was heated for 0 minutes to obtain a black matrix composed of two layers of a resin black pattern and a metallic nickel layer. At this time, the film thickness of the resin black pattern was 0.14 μm,
A large number of palladium chloride particles were generated as the protrusions 7 having a size of about 1 to 10 μm. Moreover, the nickel film was plated only on the surface of the palladium chloride particles, and was not plated at all on the part without the palladium chloride particles.

[0039]

As described above, according to the present invention, a black matrix having a low reflectance, a small number of protruding defects, and no plating adhered to a non-image area can be manufactured by a simple process. Is possible. Further, by forming colored patterns of the required number of colors on the substrate on which the black matrix is formed, a color filter having excellent display quality can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a manufacturing process of a black matrix according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a manufacturing process of a black matrix according to an embodiment of the present invention.

FIG. 3 is an explanatory view showing a manufacturing process of a black matrix by a conventional method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Black resin layer 3 ... Positive resist pattern 4 ... Resin black pattern 5, 8 ... Metal nickel layer
6 ... Oxygen barrier film 7 ... Palladium chloride particle projection

Claims (4)

[Claims] 1. A black matrix substrate comprising a transparent substrate on which a resin black pattern made of a black dispersion resin is formed, and a metal layer formed on the transparent substrate by an electroless plating method. A black matrix substrate comprising an organometallic complex of a metal or an organometallic complex of a metal nobler than the metal. 2. The metal of the metal layer is nickel, and the metal of the organometallic complex is nickel, palladium, platinum, silver,
The black matrix substrate according to claim 1, wherein the black matrix substrate is one of copper and gold. 3. The black matrix substrate according to claim 1, wherein the content of the organometallic complex is 0.1 to 20% of the total solid content of the black dispersion resin. 4. A color filter comprising a black matrix substrate according to claim 1 and a colored pattern having a required number of colors formed on the black matrix substrate.