TW201350546A - Carbbon black for black matrix and prepaeation thereof - Google Patents

Abstract

Provided is a carbon black for black matrixes, which has high insulation properties and excellent concealability. A carbon black for black matrixes, the surface of which is coated with an anionic or nonionic dark color dye. The carbon black has at least one kind of acidic functional group on the surface, and the dye is laked by a metal and affixed to the surface of the carbon black or to the acidic functional group.

Description

Carbon black for black matrix and manufacturing method thereof

The present invention relates to a carbon black for a black matrix. In detail, it relates to a carbon black for a black matrix having high insulation and excellent concealability.

In a color filter used for a liquid crystal display device or the like, a black matrix is formed between pixels which are colored in different hue, and light is blocked to prevent a decrease in color purity which is improved in contrast.

Conventionally, in the method of forming a black matrix, a metal thin film such as Cr is formed on a glass substrate by a sputtering method or the like, and a photoresist is applied onto the metal thin film, and ultraviolet light is irradiated through the photomask to perform development processing to obtain light. The pattern of the pattern is removed by etching or the like, but it is necessary to have a metal detoxification device or the like, which causes an increase in manufacturing cost.

On the other hand, a method of forming a black matrix by using a black matrix forming material in which carbon black is dispersed in a photopolymerizable compound is known. According to this method, since the material is inexpensive and the manufacturing steps are simple, the black matrix can be manufactured at low cost, but since the carbon black has electrical conductivity, the black matrix itself is formed in order to increase the carbon black concentration in the resin when the light shielding property is improved. Also conductive, It is easy to cause a problem that the image is poor due to the energization between the transparent electrode on the color filter and the black matrix or between the opposite electrodes.

Therefore, it is proposed to improve the insulating black matrix black carbon by coating carbon black with various resins (see, for example, Patent Documents 1 to 4). In such a method, a resin coating film is formed on the surface of the carbon black, and an ionic substance such as Ca or Na is sealed, and the conductors are insulated from each other by contact, thereby further preventing electrons from jumping and achieving high insulation.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 9-124969

[Patent Document 2] Japanese Patent Laid-Open No. Hei 11-080584

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2001-152046

[Patent Document 4] Japanese Laid-Open Patent Publication No. 2002-249678

However, the above-mentioned conventional technique has a problem that the concealability (OD) is lowered and the contrast or the color purity is lowered because the ratio of the carbon black in the black matrix is lowered by only the resin portion to be coated, and therefore, it is necessary to thicken the coating of the black matrix. When the film is used, there is a problem that the manufacturing cost is increased. In addition, in order to use an organic solvent for resin coating, it is necessary to provide measures against the safety at the time of manufacture or the influence on the environment. For example, it is necessary to invest in an exhaust device of a work place, an explosion-proof device of a dryer, and a wastewater treatment facility. Extremely expensive equipment investment issues.

The present invention has been made in view of the above problems in the prior art, and an object of the present invention is to provide a high-insulation property and excellent concealability in a color filter such as a liquid crystal display device, and a high contrast can be achieved even with a thin coating film. Carbon black for the black matrix of sex or color purity.

Another object of the present invention is to provide a black matrix carbon black which can be produced safely and at low cost without adversely affecting the environment.

The above object of the present invention is achieved by the following means.

(1) In other words, the present invention is a black matrix carbon black obtained by coating a surface of a carbon black with a dye.

(2) The carbon black for a black matrix according to (1), wherein the content of the dye is from 0.5 to 10% by weight.

(3) The carbon black for a black matrix according to (1) or (2), wherein the dye is an anionic or nonionic dye.

(4) The carbon black for a black matrix according to any one of (1) to (3) wherein the dye is a dark dye.

(5) The carbon black for a black matrix according to any one of (1) to (4) wherein the dye is laked by a metal or a metal salt.

(6) The carbon black for a black matrix according to (5), wherein the metal or metal salt is aluminum, magnesium, calcium, barium, strontium or manganese or a salt thereof.

(7) The carbon black for a black matrix according to any one of (1) to (6) wherein the carbon black has at least one acidic functional group on the surface.

(8) The carbon black for a black matrix according to (7), wherein the acidic functional group is a hydroxyl group, a pendant oxy group, a hydroperoxy group, a carbonyl group, a carboxyl group, a peroxycarboxylic acid group, an aldehyde group, or a ketone group. , nitro, nitroso, decylamino, quinone imine, sulfonate, sulfinate, sulfenic acid, sulfurized carboxylic acid, chlorinated, chloromethyl, perchlorinated, Iodinium or iodonium.

(9) Further, the present invention provides a method for producing carbon black for a black matrix, which comprises a dye coating step of adding a dye to a slurry of carbon black and coating the surface of the carbon black with a dye.

(10) The method for producing a black matrix carbon black according to the above aspect, wherein the dye coating step is such that the dye content in the dye-coated carbon black obtained in the dye coating step is 0.5%. The aforementioned dye was added in a 10% by weight manner.

(11) The method for producing a black matrix black matrix according to the above aspect, wherein the dye is an anionic or nonionic dye.

(12) The method for producing a black matrix black black according to any one of (9) to (11) wherein the dye is a dark dye.

(13) The method for producing a black matrix carbon black according to any one of (9) to (12), further comprising a dye which coats the surface of the carbon black by the dye coating step, by a metal Or a metal lake salting step of dyeing the metal salt.

(14) The method for producing carbon black for a black matrix according to (13), wherein the metal or metal salt is aluminum, magnesium, calcium, barium, strontium or manganese or a salt thereof.

(15) The method for producing a black matrix carbon black according to any one of (9) to (14), further comprising: oxidizing the surface of the carbon black supplied to the dye coating step with an oxidizing agent; Oxidation treatment step.

(16) The method for producing carbon black for a black matrix according to (15), wherein the oxidizing agent is ozone gas, nitric acid, sodium hypochlorite, hydrogen peroxide, nitrogen monoxide gas, nitrogen dioxide gas, anhydrous sulfuric acid, fluorine Gas, concentrated sulfuric acid, nitric acid or various peroxides.

When the surface of the carbon black is coated with a dye, the carbon black for the black matrix of the present invention can maintain high insulation and exhibit excellent concealability even when used in a black matrix of a color filter such as a liquid crystal display device. The film can still achieve high contrast or color purity. Further, it is not necessary to coat the carbon black as in the conventional resin, and it is necessary to increase the thickness of the coating film when the concealing property is improved, so that the manufacturing cost can be suppressed from increasing.

In addition, since it is not necessary to use an organic solvent for coating a carbon black as a conventional resin, it can be safely manufactured without adversely affecting the environment, and the manufacturing cost can be further reduced because no equipment investment is required.

[In order to implement the invention]

Hereinafter, embodiments of the present invention will be described in detail.

The carbon black for a black matrix of the present invention is characterized in that it is coated with a dye on a surface of carbon black.

The type of the raw material carbon black used in the present invention is not particularly limited, and known carbon blacks such as carbon black, acetylene black, thermal cracking black, channel black, and furnace black can be used.

Further, the raw material carbon black preferably has an average primary particle diameter of 5 to 60 nm, more preferably 10 to 50 nm, and most preferably 20 to 45 nm. Here, the average primary particle diameter refers to an average of the particle diameters obtained by observing 1500 carbon black particles by an electron microscope. When the average primary particle diameter of the raw material carbon black does not reach the above lower limit value, aggregation tends to occur, and the stability of the color paste becomes poor, and dispersion at a high concentration cannot be performed. Further, when the above upper limit value is exceeded, the black matrix is exceeded. The shape is not good and the surface roughness is also poor, which is not desirable.

Further, the raw material carbon black preferably has a DBP oil absorption of 100 ml/100 g or less. Here, the DBP oil absorption refers to the capacity (JIS6217) of dibutyl phthalate (DBP) which absorbs 100 g of carbon black. When the DBP oil absorption amount of the raw material carbon black exceeds the above upper limit value, the resistance value is lowered, the coating property is deteriorated due to the high viscosity, and the blackness is lowered, so that it is not desired.

In addition, the raw material carbon black preferably has a pH of 2 to 10, more preferably 5 to 9, and most preferably 4 to 8. Here, the pH value means the value of the mixture of carbon black and distilled water measured by the glass electrode pH value (JIS6221). When the pH value of the raw material carbon black does not reach the above lower limit value, the balance of the whole is collapsed, and the stability is not good. When the above upper limit is exceeded, the film peeling is likely to occur, and it is not desirable.

Further, the raw material carbon black preferably has an ash content of 1.0% or less and a specific surface area of 20 to 300 m ² /g. When the ash content exceeds the above upper limit value, the resistance value is lowered, so that it is not required. When the specific surface area is less than the above upper limit value, the carbon black matrix tends to be inferior in shape, and when it exceeds the above upper limit value, it is necessary to use A large amount of dispersants, resins, dyes, etc. are not sought.

Further, the raw material carbon black is preferably subjected to an oxidation treatment in advance, and it is preferred to have at least one acidic functional group on the surface, and to perform a plurality of oxidation treatments, and it is more preferable to have two or more kinds of acidic functional groups on the surface. If the oxidation treatment is not carried out in advance, the number of acidic functional groups or acidic functional groups is not sufficient on the surface, and the dispersibility of the obtained carbon black for black matrix cannot be sufficiently ensured, the electric resistance value is lowered, and the insulation of the black matrix is not improved. Sufficient, it is easy to cause the image to be poor between the transparent electrode on the color filter and the black matrix or between the opposite electrodes, which is not desirable. The oxidation treatment is, for example, a method using ozone gas, nitric acid, sodium hypochlorite, hydrogen peroxide, nitrogen monoxide gas, nitrogen dioxide gas, anhydrous sulfuric acid, fluorine gas, concentrated sulfuric acid, nitric acid, various peroxides, or the like, and the aforementioned acidic functional group is, for example. Hydroxy, pendant oxy, hydroperoxy, carbonyl, carboxyl, peroxycarboxylic acid, aldehyde, keto, nitro, nitroso, amidino, quinone, sulfonate, sulfinic acid A sulfenyl group, a sulfurized carboxylic acid group, a chlorinated group, a chloroindenyl group, a perchloroindenyl group, a iodonium group or an iodonium group.

The dye used in the present invention is not particularly limited as long as it can be adsorbed on the surface of carbon black, and known basic dyes, acid dyes, direct dyes, reactive dyes, and the like can be used, but Or the carboxyl group interacts with the functional group on the carbon black, the amine group reacts with the alkali-soluble resin, and can be insolubilized by sulfuric acid bonding, etc., so the anionic or nonionic dye is more Suitable for use. Further, in order to increase the light-shielding property of the obtained black matrix, it is preferable to use a black dark-based dye having a high light absorption property. Specific examples of the dye, such as Food Black No. 1, Food Black No. 2, Food Red No. 40, Food Blue No. 1, Food Yellow No. 7, etc., food dyes, Bernacid Red 2BMN, Basacid Black X34 ( BASF X-34) (manufactured by BASF Corporation), Kayanol Red 3BL (manufactured by Nippon Kayaku Company), Dermacarbon 2GT (manufactured by Sandoz Co., Ltd.), Telon Fast Yellow 4GL-175, BASF Basacid Black SE 0228, Basacid Black X34 (BASF X- 34) (According to BASF), Basacid Blue 750 (manufactured by BASF), Bernacid Red (Bemcolors, Poughkeepsie, NY), BASF Basacid Black SE 0228 (manufactured by BASF), etc., Pontamine Brilliant Bond Blue A And other Pontamine Brilliant Bond Blue A and other Pontamine (registered trademark) dyes (manufactured by Bayer Chemicals Corporation, Pittsburgh, PA), Cartasol Yellow GTF Presscake (manufactured by Sandoz, Inc.); Cartasol Yellow GTF Liquid Special 110 (Sandoz, Inc., Inc.; Yellow Shade 16948 (manufactured by Tricon), Direct Brilliant Pink B (Crompton & Knowles), Carta Black 2GT (manufactured by Sandoz, Inc.), Sirius Supra Yellow GD 167, C Artasol Brilliant Yellow 4GF (manufactured by Sandoz Co., Ltd.); Pergasol Yellow CGP (manufactured by Ciba-Geigy Co., Ltd.), Pyrazol Black BG (manufactured by JCI), Diazol Black RN Quad (manufactured by JCJ), Pontamine Brilliant Bond Blue; Direct dyes of various colors such as Berncolor AY34, Cibacron Brilliant Red 3B-A (Reactive Red 4) (Aldrich Chemical, Milwaukee, WI), Drimarene Brilliant Red X-2B (Reactive Red 56) (Pylam Products, Inc. Tempe, AZ company), Levafix Brilliant Red E-4B, Levafix Brilliant Red F-6BA and similar Levafix (registered trademark) dye Dystar LP (Charlotte, NC) dye, Procion Red H8B (Reactive Red 31) (JCI Reactive dyes of various colors such as manufactured by America Co., Ltd., Neozapon Red 492 (manufactured by BASF Corporation), Orasol Red G (manufactured by Ciba-Geigy Co., Ltd.), Aizen Spilon Red CBH (manufactured by Hodogaya Chemical Company), Spirit Fast Yellow 3G, Aizen Spilon Yellow C-GNH (manufactured by Hodogaya Chemical Company), Orasol Black RL (manufactured by Ciba-Geigy Co., Ltd.), Orasol Black RLP (manufactured by Ciba-Geigy Co., Ltd.), Savinyl Black RLS (manufactured by Sandoz), and Orasol Blue GN (Ciba-Geigy) An oil-soluble dye such as Luxol Blue MBSN (manufactured by Morton-Thiokol Co., Ltd.) or Morfast Black Concentrate A (manufactured by Morton-Thiokol Co., Ltd.). These may be used singly or in combination of two or more.

Further, the content of the dye in the carbon black for black matrix of the present invention is preferably 0.5 to 10% by mass, more preferably 1 to 7% by mass, and most preferably 1 to 5% by mass. When the content of the dye does not reach the above lower limit, the coating becomes insufficient, and a high resistance value cannot be obtained. When the above upper limit is exceeded, the residual dye which is not coated may hinder the dispersibility and tend to cause sticking. Cohesive Shape, are not seeking.

Further, the black matrix for the black matrix of the present invention is preferably a preferred one for the above dyeing by a metal or a metal salt. By the lamination, the dye is fixed to the surface of the carbon black or the acidic functional group via a metal or a metal salt, and the dye becomes less likely to be detached from the surface of the carbon black, so that the dye is less likely to be eluted and high hiding property can be maintained. The metal or metal salt to be used for the lamination, for example, aluminum, magnesium, calcium, barium, strontium or manganese or the hydrochloride, sulfate or the like of these may be used alone or in combination of two or more. The amount of the metal or metal salt to be used for the lamination is preferably 0.3 times or more with respect to the dye, more preferably 0.5 times or more, more preferably 0.8 times or more. When the amount of addition of the metal or the metal salt is less than the above range, the fixing of the dye is insufficient and it is easy to be detached from the surface of the carbon black, the stability of the color paste is not good, and the electric resistance value is also lowered, so that it is not desirable.

Next, a method of producing carbon black for a black matrix of the present invention will be described. First, the carbon black of the raw material is mixed with water (prepared by appropriately mixing ion-exchanged water in tap water having a constant electrical conductivity), and the slurry is formed, and the mixture is heated and stirred for a predetermined period of time to wash the treated carbon. Black, and washed again after cooling. Then, water is added to the obtained carbon black, and a slurry is formed again. The above oxidizing agent is added, and the mixture is stirred at a predetermined temperature for a predetermined period of time, and the surface of the carbon black is oxidized and washed with water. The oxidation treatment is carried out depending on the number of times of change required and the type of the oxidizing agent. Then, the obtained oxidized carbon black is mixed with water to form a slurry, and the dye is added to the intended black matrix carbon black in the specified content, and stirred at 40 to 90 ° C. ~5 hours to make dye adsorption Covered on the surface of carbon black. In addition, the above metal or metal salt is added in the same amount as the dye to be added, and stirred at 30 to 70 ° C for 1 to 5 hours to cause the dye to be laked with a metal or a metal salt to fix the dye on the surface of the carbon black. on. Then, after cooling, it was washed with water and dried by filtration to obtain carbon black for the intended black matrix.

The carbon black for a black matrix of the present invention can be mixed and dispersed with a photocurable resin, a photopolymerizable compound, and a solvent, and used as a composition for a black matrix. The photopolymerizable compound is not particularly limited as long as it is cured by irradiation with ultraviolet rays, and a known photopolymerizable compound can be used. Specifically, for example, acrylic acid, methacrylic acid, maleic acid, maleic imine, crotonic acid, itaconic acid, cinnamic acid, vinyl alcohol, etc., and the like; and such an isocyanate group and an acid anhydride group a reaction product of a compound such as a vinyl resin, a polyester resin, a polyamide resin, a polyimide resin, a polyurethane resin, a polyether resin, or the like, via an ester bond in a main chain or a side chain, a resin having an acryl fluorenyl group or a methacryl oxime group introduced into a guanamine bond or a urethane bond, etc., but having an alkali-soluble functional group such as a carboxyl group or a phenolic hydroxyl group in the structure and having alkali developability Preferably, it is especially preferred to have a bisphenolphthalein type epoxy acrylate structure. Further, the aforementioned solvent such as propylene glycol monomethyl ether acetate, methoxybutyl acetate cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, diethylene glycol dimethyl ether, two Ethylene glycol diethyl ether diethyl ether diethyl ether, xylene, ethyl cellosolve, methyl n-pentanone, propylene glycol monomethyl ether, toluene, methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropanol, Butanol, isobutyl ketone and the like are particularly preferably propylene glycol monomethyl ether acetate methoxybutyl acetate, cyclohexanone or the like.

Next, the carbon black for a black matrix of the present invention will be described in more detail by way of examples, but the present invention is not limited by the examples.

[Examples] [Example 1] Dye-coated carbon black (oxidized)

1000 g of carbon black (TPX-1099: manufactured by Cabot Co., Ltd.) was mixed with water to prepare 10 L of a slurry, and the mixture was stirred at 95 ° C for 1 hour, and then allowed to cool, and then washed with water. The mixture was further mixed with water to prepare a slurry of 10 L, and 42.9 g of 70% nitric acid was added thereto, and the mixture was stirred at 40 ° C for 4 hours. This was allowed to cool and washed with water, and then mixed with water to prepare a slurry of 10 L, and a 76% sodium hypochlorite aqueous solution of 769.2 g was added thereto, and the mixture was stirred at 40 ° C for 6 hours. After cooling and washing with water, the mixture was again mixed with water to prepare a slurry of 10 L, and 38.1 g of a dye (Direct Deep BLACK) having a purity of 38.4% was added, and the mixture was stirred at 40 ° C for 1 hour, and then further added with aluminum sulfate 10.1 g. Stir at 40 ° C for 1 hour. After allowing to cool, it was washed with water and filtered and dried to obtain a carbon black for a black matrix of the present invention.

Determination of the amount of carboxyl groups

The amount of the acidic functional group (the amount of carboxyl groups) of the dye-coated carbon black obtained by the following method was measured in accordance with the method described in JP-A-2000-248197.

10 g of the dye-coated carbon black was weighed and reacted in 50 ml of an aqueous solution of sodium hydrogencarbonate specified in 0.1 for 1 hour, and then filtered, and 20 ml of a supernatant liquid of the filtrate was taken, and titrated with a hydrochloric acid aqueous solution of 0.01. The amount of carboxyl groups is the amount of millimoles (mmol/g) in 1 g of carbon black obtained according to the following formula.

Carboxyl group = (50/20 × 0.01 × (titration - empty titration)) / carbon black sample quality

The amount of the carboxyl group of the obtained dye-coated carbon black was 53.9 mmol/g.

[Embodiment 2] Dye-coated carbon black (without oxidation treatment)

The black matrix black carbon of the present invention was obtained in the same manner as in Example 1 except that the oxidation treatment was not carried out by an aqueous solution of nitric acid and sodium hypochlorite. The amount of carboxyl groups of the obtained dye-coated carbon black was 3.4 mmol/g.

[Comparative Example 1] Modulation of carbon black without dye coating

A carbon black for a comparative black matrix was produced in substantially the same manner as in Example 1 except that the dye coating was not carried out and the lake was subjected to a laked treatment.

[Comparative Example 2] Resin coated carbon black modulation

Add cyclohexanone to polyvinyl chloride (Nissan Vinyl E-430, manufactured by Nissan Chemical Co., Ltd.), and heat and dissolve at about 90 ° C to prepare a cyclohexanone solution containing 10% by weight of polyvinyl chloride. . In addition, a mixture of carbon black (furnace black, Mitsubishi Chemical Co., Ltd. #3050, average primary particle diameter: 0.04 μm, specific surface area: 50 m ² /g (BET method)) and water were vigorously stirred to prepare 6% by weight of carbon black. A homogeneous suspension. Then, stirring is carried out in the aforementioned cyclohexanone solution and a suspension is added to transfer the carbon black of the aqueous phase to the solvent phase. Thereafter, the water separated from the carbon black was removed by separation, and then kneaded by a roll mill having two rolls heated at 80 to 120 ° C for about 5 minutes to obtain a resin composition. Then, the resin composition was cut into a sheet shape by a heating roll, passed through a roll mill having two rolls at normal temperature, and pulverized to a size of about 30 mm or less, then transferred to water, and stirred at a speed of about 3000 rpm. After 3 minutes, the granules were pulverized into granules having a particle diameter of 0.1 to 3 mm to obtain a granule. The granules were dried at 80 to 150 ° C to obtain resin-coated carbon black.

[assessment] Modification of coating solution for carbon black

The carbon black for black matrices obtained in each of Examples 1 and 2 and Comparative Examples 1 and 2 was subjected to bead mill to disperse 300 g of carbon black for black matrix and BYK-167 of urethane-based dispersant (BYK. Japan Co., Ltd. Of the propylene glycol monomethyl ether acetate solution (resin solid content concentration = 55.5 mass%, "V259ME" manufactured by Nippon Steel Chemical Co., Ltd.), which is 46.6 g, and an acrylic acid epoxy ester acid addition product having an anthracene skeleton, 189.2 g, A base ink is obtained. In the base oil A propylene glycol monomethyl ether acetate solution (resin solid content concentration = 55.5 mass%, "V259ME" manufactured by Nippon Steel Chemical Co., Ltd.) having a ruthenium-based acrylate acrylate acid addition product was added to the ink of 20 g, and propylene glycol was added thereto. 21.9 g of monomethyl ether acetate was adjusted to adjust the coating liquid.

Determination of OD value, surface roughness and surface resistance value

The coating liquid obtained above was applied onto a glass substrate by a spin coater, dried at 90 ° C for 2 minutes, and further cured by heating at 220 ° C for 30 minutes to obtain a dried coating film.

The OD value of the obtained dried coating film was measured by a reflection densitometer, and the film thickness and surface roughness were measured by Tencor Alpha-step IQ, and the surface resistance value measuring device ("HIRESTA" manufactured by Mitsubishi Chemiacl Analytech Co., Ltd.) was used. The surface resistance value was measured, and the results are shown in Table 1.

As is clear from the results of Table 1, the carbon black for the black matrix of the present invention (Examples 1 and 2) can obtain an extremely high surface resistance value when compared with the carbon black (Comparative Example 1) which is not coated with the dye, and at the same time, When the conventional resin-coated carbon black (Comparative Example 2) is compared, an extremely high OD value can be obtained.

[Industry use value]

As described above, the carbon black for a black matrix of the present invention is extremely useful for use in a black matrix of a color filter such as a liquid crystal display device because of its high insulating properties and excellent concealability.

Claims (16)

A black matrix carbon black obtained by coating a carbon black surface with a dye. The carbon black for the black matrix of claim 1, wherein the content of the dye is 0.5 to 10% by weight. The black matrix of claim 1 or 2 is carbon black, wherein the dye is an anionic or nonionic dye. The carbon black for a black matrix according to any one of claims 1 to 3, wherein the dye is a dark dye. The carbon black for a black matrix according to any one of claims 1 to 4, wherein the dye is laked by a metal or a metal salt. The black matrix of claim 5, wherein the metal or metal salt is aluminum, magnesium, calcium, barium, strontium or manganese or a salt thereof. The carbon black for a black matrix according to any one of claims 1 to 6, wherein the carbon black has at least one acidic functional group on the surface. The carbon black of the black matrix of claim 7, wherein the acidic functional group is a hydroxyl group, a pendant oxy group, a hydroperoxy group, a carbonyl group, a carboxyl group, a peroxycarboxylic acid group, an aldehyde group, a ketone group, a nitro group, a nitroso group , amidino, quinone, sulfonate, sulfinate, sulfenic acid, sulfurized carboxylic acid, chlorinated, chloroindenyl, perchlorinated, iodosinyl or iodonium base. A method for producing carbon black for a black matrix, which comprises a dye coating step of adding a dye to a slurry of carbon black and coating a surface of the carbon black with a dye. A method of manufacturing carbon black for a black matrix according to claim 9, wherein In the dye coating step, the dye is added so that the content of the dye in the dye-coated carbon black obtained is 0.5 to 10% by weight. A method of producing carbon black for a black matrix according to claim 9 or 10, wherein the dye is an anionic or nonionic dye. The method for producing carbon black for a black matrix according to any one of claims 9 to 11, wherein the dye is a dark dye. The method for producing carbon black for a black matrix according to any one of claims 9 to 12, further comprising a dye for causing a dye coated with a surface of the carbon black obtained by the dye coating step to be laked by a metal or a metal salt Deionization step. A method of producing carbon black for a black matrix according to claim 13, wherein the metal or metal salt is aluminum, magnesium, calcium, barium, strontium or manganese or a salt thereof. The method for producing carbon black for a black matrix according to any one of claims 9 to 14, further comprising an oxidation treatment step of oxidizing the surface of the carbon black supplied to the dye coating step with an oxidizing agent. The method for producing a black matrix for a black matrix according to claim 15, wherein the oxidizing agent is ozone gas, nitric acid, sodium hypochlorite, hydrogen peroxide, nitrogen monoxide gas, nitrogen dioxide gas, anhydrous sulfuric acid, fluorine gas, concentrated sulfuric acid, nitric acid or Various peroxides.