Surface-modified carbon black, carbon black dispersion, and black resist composition

Abstract

To provide carbon black with superior dispersibility and dispersion stability.SOLUTION: The present invention provides surface-modified carbon black in which polymers of double bond-containing polymerizable monomers exist on a portion or the entirety of the carbon black surface, wherein the polymers of double bond-containing polymerizable monomers contain calixarene compounds.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to surface-modified carbon black, a carbon black dispersion, a black resist composition, and a method for producing the surface-modified carbon black.

Background Art

[0002] Currently, carbon black is widely used as a coloring pigment and a light-shielding material in fields such as printing inks, paints, and plastic molding materials. In order to improve the coloring property and light absorption performance in these products, it is necessary to uniformly disperse carbon black in a solvent or a resin. For example, in a carbon black dispersion for forming a black matrix of a color filter used in a liquid crystal display element, a sensor, etc., improvement in the dispersibility and dispersion stability of carbon black is required for the purpose of further improving the luminance. However, generally, carbon black has poor dispersibility, so improvement in dispersibility by surface treatment has been studied.

[0003] As a surface treatment of carbon black for the purpose of improving dispersibility, surface modification with an alkyl group type surface treatment agent having an amino group has been studied (for example, Patent Document 1). However, in the surface modification with the above surface treatment agent, the surface modification density required for improving dispersibility cannot be obtained, so the improvement in dispersibility has been insufficient.

[0004] A method of reacting a carboxyl group on the carbon black surface with an amine-based surface treatment agent has also been studied for the purpose of improving the surface modification density (for example, Patent Document 2). However, in this method, since it is necessary to chlorinate the carboxyl group on the carbon black surface, the process becomes complicated, and the remaining chlorine may cause migration, which may cause failures in liquid crystal display elements, cameras, etc.

[0005] On the other hand, improving the surface modification density by performing the surface treatment of carbon black in a reaction solvent has also been considered (for example, Patent Document 3). However, in this method, residual sulfur derived from the sulfonating agent may cause migration in the same manner as chlorine, and since the length of the solvent affinity group is not sufficient, the dispersibility for satisfying the luminance of state-of-the-art liquid crystal display elements, sensors, etc. has not been achieved.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] As described above, with the increasing high definition of liquid crystal display elements and the increasing sensitivity of sensors, etc., carbon black and its dispersion having more excellent dispersibility and dispersion stability are required. An object of the present invention is to provide carbon black and its dispersion having excellent dispersibility and dispersion stability.

Means for Solving the Problems

[0008] As a result of intensive studies to solve the above problems, the present inventors have found that by reacting a mixture containing carbon black, a calixarene compound, and a double bond-containing polymerizable monomer, surface-modified carbon black having excellent dispersibility and dispersion stability can be obtained, and thus completed the present invention.

[0009] That is, the present invention relates to a surface-modified carbon black in which a polymer of a double bond-containing polymerizable monomer is present on part or all of the surface of the carbon black, and the polymer of the double bond-containing polymerizable monomer contains a calixarene compound. The present invention also relates to a carbon black dispersion containing the above surface-modified carbon black. The present invention also relates to a black resist composition containing the above surface-modified carbon black. The present invention also relates to a method for producing surface-modified carbon black, which comprises preparing a mixture containing (A) carbon black, (B) a calixarene compound, (C) a double bond-containing polymerizable monomer, (D) a solvent, and (E) a polymerization initiator, and polymerizing the (C) double bond-containing polymerizable monomer.

Advantages of the Invention

[0010] According to the present invention, carbon black and its dispersion having excellent dispersibility and dispersion stability can be provided.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, an embodiment of the present invention will be described. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications without impairing the effects of the present invention. In the present specification, “(meth)acrylate” means one or both of acrylate and methacrylate.

[0012] 1. Surface-Modified Carbon Black The surface-modified carbon black according to an embodiment of the present invention is characterized in that a polymer of a double bond-containing polymerizable monomer is present on part or all of the surface of the carbon black, and the polymer of the double bond-containing polymerizable monomer contains a calixarene compound. Thereby, carbon black having excellent dispersibility and dispersion stability can be obtained. Hereinafter, the constituent components will be described.

[0013] [(a) Carbon black] The carbon black is not particularly limited, and various commercially available oil furnace black, gas furnace black, thermal black, acetylene black, channel black, etc. can be used. Further, ozone-treated, plasma-treated, or liquid-phase oxidized carbon black that is commonly performed may also be used. The carbon black may be used alone or in combination of two or more kinds.

[0014] The blending amount of the carbon black is preferably in the range of 40% by mass or more and 94.9% by mass or less, and more preferably in the range of 60% by mass or more and 89.5% by mass or less, based on the total mass of (a) carbon black, (b) calixarene compound, and (c) polymer of the double bond-containing polymerizable monomer.

[0015] The shape of the carbon black is not particularly limited and can be selected according to the use, such as for improving conductivity, for ink (for light shielding), for fiber coloring, for resin masterbatch, etc. Examples of commercially available carbon blacks include MA7, MA8, MA11, MA100, MA100R, MA220, MA230, MA600, #5, #10, #20, #25, #30, #32, #33, #40, #44, #45, #47, #50, #52, #55, #650, #750, #850, #950, #960, #970, #980, #990, #1000, #2200, #2300, #2350, #2400, #2600, #3050, #3150, #3250, #3600, #3750, #3950, #4000, #4010, OIL7B, OIL9B, OIL11B, OIL30B, OIL31B, etc. manufactured by Mitsubishi Chemical Corporation; Printex3, Printex3OP, Printex30, Printex30OP, Printex40, Printex45, Printex55, Printex60, Printex75, Printex80, Printex85, Printex90, Printex A, Print ex L, Printex G, Printex P, Printex U, Printex V, PrintexG, SpecialBlack550, SpecialBlack 350, SpecialBlack250, SpecialBlack100, SpecialBlack6, SpecialBlack5, SpecialBlack4, Color Black FW1, Colo r Black FW2, Color Black FW2V, Color Black FW18, Color Black FW18, Color Black FW200, Color Black S160, Color Black S170, etc. manufactured by Evonik Degussa Japan Co., Ltd.; Monarch120, Monarch280, Monarch460, Monarch800, Monarch880, Monarch900, Monarch1000, Monarch1100, Monarch1300, Monarch1400, Monarch4630, REGAL99, REGAL99R, REGAL415, REGAL415R, REGAL250, REGAL250R, REGAL330, REGAL400R, REGAL55R0, REGAL660R, BLACKExamples include PEARLS480, PEARLS130, VULCAN XC72R, ELFTEX-8, etc., and RAVEN11, RAVEN14, RAVEN15, RAVEN16, RAVEN22, RAVEN30, RAVEN35, RAVEN40, RAVEN410, RAVEN420, RAVEN450, RAVEN500, RAVEN780, RAVEN850, RAVEN890H, RAVEN1000, RAVEN1020, RAVEN1040, RAVEN1060U, RAVEN1080U, RAVEN1170, RAVEN1190U, RAVEN1250, RAVEN1500, RAVEN2000, RAVEN2500U, RAVEN3500, RAVEN5000, RAVEN5250, RAVEN5750, RAVEN7000, etc. manufactured by Columbian Carbon Company.

[0016] [(b) Calixarene compound] The calixarene compound is contained in the polymer of the double bond-containing polymerizable monomer described later. The fact that the polymer contains the calixarene compound can be confirmed by gel permeation chromatography (GPC) or gas chromatography-mass spectrometry (GC-MS). The calixarene compound is preferably a compound represented by the following formula (1).

[0017] [Chemical formula] (In the formula, R1 is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group. R2 and R3 are each independently a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, or an aralkyl group. n is an integer of 3 to 6.)

[0018] Specifically, R1 in the above formula (1) includes alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, t-butyl group, pentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, etc.; aryl groups such as phenyl group, naphthyl group, anthryl group, etc. Among them, R1 is preferably an alkyl group or an aryl group having 1 to 11 carbon atoms, and more preferably a linear alkyl group or a phenyl group having 2 to 9 carbon atoms. When R1 has a substituent, examples of the substituent include an alkyl group, an alkoxy group, an aryl group, an aralkyl group, etc. Specific examples include the groups exemplified by R2 described later.

[0019] R2 and R3 in the above formula (1) are each a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, or an aralkyl group. Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, cyclohexyl group. The number of carbon atoms is preferably 1 to 9, for example. Examples of the alkoxy group include methoxy group, ethoxy group, propyloxy group, butoxy group, pentyloxy group, hexyloxy group, cyclohexyloxy group. The number of carbon atoms is preferably 1 to 9, for example.

[0020] Examples of the aryl group include those having 6 to 14 carbon atoms forming a ring. The aryl group may have substituents such as the above-described alkyl group, alkoxy group, and hydroxy group. Specifically, phenyl group, hydroxyphenyl group, dihydroxyphenyl group, hydroxyalkoxyphenyl group, alkoxyphenyl group, tolyl group, xylyl group, naphthyl group, hydroxynaphthyl group, dihydroxynaphthyl group can be mentioned.

[0021] The aralkyl group is an alkyl group (C n H 2n+1It means an alkyl group in which one or more of the hydrogen atoms of ()) are substituted with an aryl group. The aryl group may have substituents such as the alkyl group, alkoxy group, and hydroxy group described above. Specifically, phenylmethyl group, hydroxyphenylmethyl group, dihydroxyphenylmethyl group, tolylmethyl group, xylylmethyl group, naphthylmethyl group, hydroxynaphthylmethyl group, dihydroxynaphthylmethyl group, phenylethyl group, hydroxyphenylethyl group, dihydroxyphenylethyl group, tolylethyl group, xylylethyl group, naphthylethyl group, hydroxynaphthylethyl group, dihydroxynaphthylethyl group can be mentioned. The number of carbon atoms is preferably, for example, 7 to 15.

[0022] In one embodiment, R2 and R3 in the above formula (1) are preferably hydrogen atoms.

[0023] The compound represented by the above formula (1) can be synthesized from a resorcin derivative represented by the following formula (2) (resorcin is a common name, the acceptable common name is resorcinol, and the IUPAC name is 1,3-dihydroxybenzene.) and an aldehyde compound.

[0024]

Chemical formula

[0025] In one embodiment, R2 and R3 of the compound represented by the above formula (2) are preferably both hydrogen atoms. Also, in one embodiment, the aldehyde compound is preferably an aldehyde compound having an alkyl group which may have a substituent or an aryl group which may have a substituent, more preferably an aldehyde compound having an alkyl group or aryl group with 1 to 12 carbon atoms, and even more preferably an aliphatic aldehyde compound having an alkyl group with 3 to 10 carbon atoms or an aldehyde compound having a phenyl group.

[0026] The calixarene compound may be used alone or in combination of two or more. The calixarene compound can be obtained as a commercially available product or by a known synthesis method. The blending amount of the calixarene compound is preferably in the range of 0.1% by mass or more and 20% by mass or less, more preferably in the range of 0.5% by mass or more and 10% by mass or less, based on the total mass of (a) carbon black, (b) the calixarene compound, and (c) the double bond-containing polymerizable monomer.

[0027] [Polymer of (c) double bond-containing polymerizable monomer] The polymer of the double bond-containing polymerizable monomer exists in a core-shell structure so as to cover all or part of the surface of the carbon black. The presence of the polymer on all or part of the surface of the carbon black can be confirmed by weight loss by thermogravimetric analyzer (TGA) evaluation. The polymer of the double bond-containing polymerizable monomer may be an oligomer or a polymer obtained by polymerizing the monomer. Here, the oligomer means a polymer having a degree of polymerization of about 2 to 100, and the polymer means a polymer having a degree of polymerization exceeding 100.

[0028] Examples of the double bond-containing polymerizable monomer include styrene compounds such as styrene, α-methylstyrene, and p-methylstyrene; divinylbenzene; acrylonitrile; methacrylonitrile; methyl (meth)acrylate; ethyl (meth)acrylate; butyl (meth)acrylate; glycidyl (meth)acrylate; glycidyl vinyl ether; 2-hydroxyethyl (meth)acrylate; 2-hydroxybutyl (meth)acrylate; 4-vinylcyclohexene 1,2-epoxide; epoxycyclohexenyl (meth)acrylate; 2-oxetanylpropyl (meth)acrylate; ethylene glycol di(meth)acrylate; 1,3-butylene glycol di(meth)acrylate. Among them, styrene compounds or (meth)acrylates are preferred. The double bond-containing polymerization reactive monomer may be used alone or in combination of two or more kinds.

[0029] In one embodiment of the present invention, the weight average molecular weight of the polymer of the double bond-containing polymerization reactive monomer is preferably 300 or more and preferably 5,000 or less. In one embodiment of the present invention, the average degree of polymerization of the polymer of the (c) double bond-containing polymerization reactive monomer is preferably 3 or more and preferably 50 or less.

[0030] In one embodiment of the present invention, the blending amount of the polymer of the double bond-containing polymerization reactive monomer is preferably in the range of 5% by mass or more and 50% by mass or less, and more preferably in the range of 10% by mass or more and 30% by mass or less, based on the total mass of (a) carbon black, (b) calixarene compound, and (c) double bond-containing polymerization reactive monomer.

[0031] In one embodiment, the surface-modified carbon black may consist essentially of only (a) carbon black, (b) calixarene compound, and (c) the polymer of the double bond-containing polymerization reactive monomer. Here, consisting essentially of only the components (a) to (c) means that the proportion of the components (a) to (c) in the surface-modified carbon black is 90% by mass or more, 95% by mass or more, 99% by mass or more, or 100% by mass. When the proportion of the components (a) to (c) is 100% by mass, it may contain inevitable impurities.

[0032] The surface-modified carbon black of the present invention can be suitably used in fields where light-shielding properties, conductivity, durability, jet-blackness, etc. are required, for example, gravure ink, offset ink, backcoat for magnetic recording media, electrostatic toner, inkjet, automotive paint, conductive carbon black, coloring pigment for liquid crystal display elements and sensors, light-shielding material, black resist, paint, plastic molding material, printing ink, packaging material, adhesive, negative electrode material, etc.

[0033] 2. Method for Producing Surface-Modified Carbon Black The method for producing surface-modified carbon black according to one embodiment of the present invention comprises the step of preparing a mixture (reaction system) containing (A) carbon black, (B) a calixarene compound, (C) a double bond-containing polymerizable monomer, (D) a solvent, and (E) a polymerization initiator, and polymerizing (C) the double bond-containing polymerizable monomer.

[0034] In this embodiment, the dispersibility of carbon black is improved by polymerizing a double bond-containing polymerizable monomer in the presence of a calixarene compound. This is because part or all of the carbon black surface is covered with a polymer of the double bond-containing polymerizable monomer. When the calixarene compound is not blended, the effects of the present invention are not exhibited. In the polymerization reaction, it is not clear how the calixarene compound is involved, but it is presumed that the calixarene compound is adsorbed on the carbon black surface by chemical bonds or intermolecular interactions, or the calixarene compound is present around the carbon black, causing the polymerization reaction of the double bond-containing polymerizable monomer to occur on all or part of the carbon black surface. Further, since the calixarene compound represented by the formula (1) can be presumed to intervene in the reaction between carbon black and the double bond-containing polymerizable monomer as described above, it is presumed to have an effect such as a certain kind of catalytic action.

[0035] In this embodiment, the details and blending amounts of (A) carbon black, (B) the calixarene compound, and (C) the double bond-containing polymerizable monomer are the same as those of (a) carbon black, (b) the calixarene compound, and (c) the double bond-containing polymerizable monomer of the surface-modified carbon black described above.

[0036] [(D) Solvent] Examples of the solvent include ketones such as acetone, methyl ethyl ketone, cyclohexanone, cyclopentanone, cycloheptanone, 2-heptanone, methyl isobutyl ketone, and butyrolactone; alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, pentanol, heptanol, octanol, nonanol, and decanol; ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and dioxane; alcohol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol monopropyl ether; esters such as ethyl formate, propyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl butyrate, ethyl butyrate, butyl butyrate, propyl butyrate, ethyl lactate, and butyl lactate; monocarboxylic acid esters such as methyl 2-oxypropionate, ethyl 2-oxypropionate, propyl 2-oxypropionate, butyl 2-oxypropionate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, and butyl 2-methoxypropionate; cellosolve esters such as cellosolve acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propyl cellosolve acetate, and butyl cellosolve acetate; propylene glycols such as propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monobutyl ether acetate; diethylene glycols such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol methyl ethyl ether; aromatics such as toluene and xylene;Examples of the polar solvents include dimethylacetamide, dimethylformamide, N-methylacetamide, N-methylpyrrolidone, and the like.; The selection of the above solvents is appropriately made in consideration of the boiling point and raw materials. The above solvents can be used alone or in combination of two or more kinds. (D) The blending amount of the solvent is preferably in the range of 30 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass in total of components (A) to (C) and (E).

[0037] [(E) Polymerization initiator] As the polymerization initiator, various ones can be used. For example, peroxides such as acetyl peroxide, diacyl peroxide, cumyl peroxide, t-butyl peroxide, propionyl peroxide, benzoyl peroxide, 2-chlorobenzoyl peroxide, 3-chlorobenzoyl peroxide, 4-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, 4-bromomethylbenzoyl peroxide, lauroyl peroxide, diisopropyl peroxydicarbonate, tetralin hydroperoxide, t-butyl peroxy-2-ethylhexanoate, 1-phenyl-2-methylpropyl-1-hydroperoxide, t-butyl pertrifluoroacetate, t-butyl hydroperoxide, t-butyl peroxyformate, t-butyl peracetate, t-butyl perbenzoate, t-butyl per-2-ethylhexanoate, t-butyl perphenylacetate, t-butyl per-4-methoxyacetate; azo compounds such as 2,2'-dichloro-2,2'-azobispropane, 1,1'-azo(methylethyl)diacetate, 2,2'-azobis(2-amidinopropane) nitrate, 2,2'-azobisisobutane, 2,2'-azobisisobutyramide, 2,2'-azobisisobutyronitrile, methyl 2,2'-azobis-2-methylpropionate, 2,2'-dichloro-2,2'-azobutane, 2,2'-azobis-2-methylbutyronitrile, dimethyl 2,2'-azobisisobutyrate, dimethyl 2,2'-azobisisobutyrate, 2-(4-methylphenylazo)-2-methylmalonodinitrile, 4,4'-azobis-4-cyanovaleric acid, 3,5-dihydroxymethylphenylazo-2-methylmalonodinitrile, 1,1'-azobis-1-cyclohexanecarbonitrile, 1,1'-azobis-1-phenylethane, 1,1'-azobiscumene, ethyl 4-nitrophenylazobenzylcyanoacetate, phenylazodiphenylmethane, phenylazotriphenylmethane, 4-nitrotriphenylazotriphenylmethane, 1,1'-azobis-1,2-diphenylethane; azo compounds such as azobisisobutyronitrile, dimethyl azobisisobutyrate, phenylazotriphenylmethane; metal chelate compounds such as Mn(acac)3, etc. can be mentioned. If necessary, chain transfer agents such as lauryl mercaptan, thioglycerol, 2-mercaptoethanol, ethyl thioglycolic acid, octyl thioglycolic acid, etc., and thiol compounds having a coupling group such as γ-mercaptopropyltrimethoxysilane may be used as additives such as chain transfer agents. (E) The blending amount of the polymerization initiator is preferably in the range of 0.1 part by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the component (C).

[0038] In this embodiment, the mixture containing the above components is polymerized, for example, by mixing and stirring while heating to polymerize the (C) double bond-containing polymerizable monomer. As the method of mixing and stirring, it is preferably carried out by a known method.

[0039] In the production method of this embodiment, the reaction temperature varies depending on each raw material used, but from the viewpoints of reaction rate, solvent selectivity (solvent boiling point), and prevention of gelation, it is preferably carried out at 40 °C or higher and 200 °C or lower. More preferably, it is 70 °C or higher and 170 °C or lower. In the production method of the present invention, the reaction time is preferably 4 hours or more, more preferably 12 hours or more, from the viewpoints of complete termination of the reaction, reaction reproducibility, and production cost. Also, it is preferably 32 hours or less, more preferably 24 hours or less. After completion of the reaction, it is preferable to wash the obtained solid matter, perform reprecipitation operation, and drying to purify the surface-modified carbon black.

[0040] 3. Carbon black dispersion A carbon black dispersion according to an embodiment of the present invention (hereinafter, may be simply referred to as "dispersion") is a dispersion containing the above surface-modified carbon black and a dispersion medium. The dispersion medium is not particularly limited as long as it is a liquid capable of dispersing the surface-modified carbon black of the present invention. For example, the solvent used in the production method of the surface-modified carbon black of the present invention described above is preferable. Only one kind of dispersion medium may be used, or two or more kinds may be mixed and used.

[0041] The concentration of the surface-modified carbon black in the carbon black dispersion is not particularly limited and can be appropriately adjusted according to the use of the carbon black. Usually, it is 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the dispersion medium.

[0042] The method for dispersing the surface-modified carbon black in the dispersion medium is not particularly limited, and known methods can be adopted. Examples of the disperser include a three-roll mill or a two-roll mill that finely disperses carbon black particles by shear stress, a ball mill, an attritor, a sand mill, a coball mill, a basket mill, a vibration mill, a paint conditioner, etc. that finely disperse carbon black particles by the impact force of media such as glass beads and zirconia beads, a disper, a homogenizer, a Clearmix(R), etc. that finely disperse by a rotating blade that generates shear stress, cavitation, collision force, potential core, etc., a kneader, an extruder, a jet mill, etc. that finely disperse by the collision force or shear force between carbon black particles or between carbon black particles and the vehicle or the wall surface of the disperser, an ultrasonic disperser that finely disperses by ultrasonic waves, etc., but it is not limited thereto.

[0043] The carbon black dispersion according to this embodiment may contain components other than the above-described surface-modified carbon black and the dispersion medium. For example, a binder component, a dispersant, a lubricant, an activator, a crosslinking agent, a leveling agent, an antifoaming agent, a solvent, a lubricant, a leveling agent, an antifoaming agent, a preservative, etc. can be mentioned.

[0044] 4. Black resist composition The black resist composition according to one embodiment of the present invention contains the surface-modified carbon black of the present invention. In this embodiment, since the surface-modified carbon black of the present invention has excellent dispersibility and dispersion stability, a glossy and uneven-free coating film (cured product) can be formed. The black resist composition of this embodiment only needs to contain the surface-modified carbon black of the present invention, and other components and the like are not particularly limited. Further, the black resist composition of this embodiment can be produced by a known method. For example, reference can be made to Japanese Patent Application Laid-Open No. 2015-227406.

[0045] The black resist composition of this embodiment contains known constituent members such as the surface-modified carbon black of the present invention, an alkali-soluble resin, a solvent, a polymerizable compound, a photopolymerization initiator, and the like. An alkali-soluble resin is a resin soluble in an alkaline solution which is a developer used at the time of patterning a resist. Examples of the alkali-soluble resin include novolak resins obtained by condensing aromatic hydroxy compound derivatives such as phenol, cresol, xylenol, resorcinol, phloroglucinol, hydroquinone, etc. with aldehyde compounds such as formaldehyde, acetaldehyde, benzaldehyde, etc.; polymers or copolymers of vinylphenol compound derivatives such as o-vinylphenol, m-vinylphenol, p-vinylphenol, α-methylvinylphenol, etc.; (meth)acrylic acid-based polymers or copolymers such as acrylic acid, methacrylic acid, hydroxyethyl (meth)acrylate, etc.; polyvinyl alcohol; modified resins obtained by introducing radiation-sensitive groups such as quinonediazide groups, naphthoquinone azide groups, aromatic azide groups, aromatic cinnamoyl groups, etc. through a part of the hydroxyl groups of these various resins; urethane resins containing acidic groups such as carboxylic acid, sulfonic acid, etc. in the molecule; resins having a fluorene skeleton, epoxy (meth)acrylate and acid anhydride polycondensates, etc. These alkali-soluble resins may be used alone or in combination of two or more.

[0046] As solvents for the black resist composition, for example, ketones such as acetone, methyl ethyl ketone, cyclohexanone, cyclopentanone, cycloheptanone, 2-heptanone, methyl isobutyl ketone, butyrolactone; alcohols such as methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butyl alcohol, iso-butyl alcohol, tert-butyl alcohol, pentanol, heptanol, octanol, nonanol, decanol; ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dioxane; alcohol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether; esters such as ethyl formate, propyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl butyrate, ethyl butyrate, butyl butyrate, propyl butyrate, ethyl lactate, butyl lactate; monocarboxylic acid esters such as methyl 2-oxypropionate, ethyl 2-oxypropionate, propyl 2-oxypropionate, butyl 2-oxypropionate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, butyl 2-methoxypropionate; cellosolve esters such as cellosolve acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propyl cellosolve acetate, butyl cellosolve acetate; propylene glycols such as propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate; diethylene glycols such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether;Halogenated hydrocarbons such as trichloroethylene, Freon solvents, HCFCs, and HFCs; fully fluorinated solvents such as perfluorooctane, aromatics such as toluene and xylene; polar solvents such as dimethylacetamide, dimethylformamide, N-methylacetamide, and N-methylpyrrolidone. These solvents may be used alone or in combination of two or more.

[0047] The polymerizable compound is, for example, a compound having a photopolymerizable functional group capable of undergoing polymerization or crosslinking reaction upon irradiation with active energy rays such as ultraviolet rays. Examples of the above polymerizable compounds include unsaturated carboxylic acids such as (meth)acrylic acid, esters of monohydroxy compounds and unsaturated carboxylic acids, esters of aliphatic polyhydroxy compounds and unsaturated carboxylic acids, esters of aromatic polyhydroxy compounds and unsaturated carboxylic acids, esters obtained by esterification reaction of unsaturated carboxylic acids with polyvalent carboxylic acids and polyvalent hydroxy compounds such as the aforementioned aliphatic polyhydroxy compounds and aromatic polyhydroxy compounds, polymerizable compounds having a urethane skeleton obtained by reacting a polyisocyanate compound with a (meth)acryloyl group-containing hydroxy compound, polymerizable compounds having an acid group, and the like. The polymerizable compound may be used alone or in combination of two or more.

[0048] Examples of the ester of the aliphatic polyhydroxy compound and the unsaturated carboxylic acid include (meth)acrylic acid esters such as ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and glycerol (meth)acrylate. In addition, itaconic acid esters obtained by replacing the (meth)acrylic acid moiety of these acrylates with itaconic acid, crotonic acid esters obtained by replacing it with crotonic acid, maleic acid esters obtained by replacing it with maleic acid, etc. may also be mentioned.

[0049] Examples of the ester of the aromatic polyhydroxy compound and the unsaturated carboxylic acid include hydroquinone di(meth)acrylate, resorcin di(meth)acrylate, pyrogallol tri(meth)acrylate, and the like. The ester obtained by the esterification reaction of the unsaturated carboxylic acid, the polyvalent carboxylic acid, and the polyvalent hydroxy compound may be a single substance or a mixture. Examples of such esters include esters obtained from (meth)acrylic acid, phthalic acid, and ethylene glycol; esters obtained from (meth)acrylic acid, maleic acid, and diethylene glycol; esters obtained from (meth)acrylic acid, terephthalic acid, and pentaerythritol; esters obtained from (meth)acrylic acid, adipic acid, butanediol, and glycerin, and the like.

[0050] Examples of the polymerizable compound having a urethane skeleton obtained by reacting the polyisocyanate compound with the (meth)acryloyl group-containing hydroxy compound include aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; alicyclic diisocyanates such as cyclohexane diisocyanate and isophorone diisocyanate; aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane diisocyanate, and reaction products with hydroxy compounds having a (meth)acryloyl group such as 2-hydroxyethyl (meth)acrylate and 3-hydroxy[1,1,1-tri(meth)acryloyloxymethyl]propane.

[0051] Examples of the polymerizable compound having an acid group include esters of aliphatic polyhydroxy compounds and unsaturated carboxylic acids, and polyfunctional polymerizable compounds having acid groups formed by reacting non-aromatic carboxylic anhydrides with unreacted hydroxyl groups of aliphatic polyhydroxy compounds are preferred. As the aliphatic polyhydroxy compound used in the preparation of the polyfunctional polymerizable compound, pentaerythritol or dipentaerythritol is preferred. Since the acid value of the polyfunctional polymerizable compound results in good developability, curability, etc., the range of 0.1 to 40 is preferred, and the range of 5 to 30 is more preferred. When two or more polyfunctional polymerizable compounds having acid groups are used in combination, and when a polyfunctional polymerizable compound having an acid group and a polyfunctional polymerizable compound having no acid group are used in combination, it is preferable that the acid value of the mixture of the polymerizable compounds is within the above range.

[0052] Specific examples of the polymerizable compound having an acid group include mixtures mainly composed of dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, and succinic acid esters of dipentaerythritol pentaacrylate, and the mixture is commercially available as Aronix TO-1382 (manufactured by Toagosei Co., Ltd.).

[0053] Examples of polymerizable compounds other than the above include (meth)acrylamides such as ethylenebis(meth)acrylamide; allyl esters such as diallyl phthalate; compounds having vinyl groups such as divinyl phthalate.

[0054] The content of the polymerizable compound is preferably in the range of 5 to 80% by mass, more preferably in the range of 10 to 70% by mass, and even more preferably in the range of 20 to 50% by mass in the total solid content of the resist composition.

[0055] A photopolymerization initiator refers to a compound that generates radicals by bond cleavage and / or reaction upon exposure. By containing a photopolymerization initiator, the curing of the exposed portion is promoted, and the sensitivity can be improved.

[0056] The photoinitiator is not particularly limited, and known photoinitiators can be used. Examples of the photoinitiator include benzyl ketal-based photoinitiators, α-hydroxy ketone-based photoinitiators, α-amino ketone-based photoinitiators, acylphosphine oxide-based photoinitiators, oxime ester-based photoinitiators, acridine-based photoinitiators, titanocene-based photoinitiators, benzophenone-based photoinitiators, acetophenone-based photoinitiators, aromatic ketoester-based photoinitiators, benzoic acid ester-based photoinitiators, and the like.

[0057] The photoinitiator may be used alone or in combination of two or more. The blending amount of the photoinitiator is preferably 0.1 part by mass or more, more preferably 5 parts by mass or more, based on 100 parts by mass of the alkali-soluble resin, since good sensitivity can be obtained and a desired pattern can be obtained. Further, it is preferably 20 parts by mass or less, more preferably 15 parts by mass or less.

[0058] Regarding the coating method, any known and publicly available coating method can be used. Examples include slit coater, slit & spin coater, spin coater, roll coater, electrostatic coating, bar coater, gravure coater, die coater, knife coater, inkjet, dipping coating, spray coating, shower coating, screen printing, gravure printing, offset printing, reverse coating, and the like. After coating and drying, a cured film of the black resist composition is obtained. The cured film is suitable for, for example, a black matrix used in a display device.

Examples

[0059] Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. Note that the embodiments of the present invention are not limited to the following Examples.

[0060] [Synthesis of Calixarene Compound] (Synthesis Example 1) In a 500 ml four-necked flask equipped with a cooling tube, 37.5 g (0.34 mol: manufactured by Fuji Film Wako Pure Chemical Industries, 1,3-dihydroxybenzene) of resorcinol, 53.0 g (0.34 mol: manufactured by Kao Chemicals, aliphatic aldehyde with 10 carbon atoms) of decyl aldehyde, 94.0 g of butanol, and 3.8 g of 95% sulfuric acid were charged, and the mixture was stirred and reacted for 4 hours under reflux at 80 °C using a mantle heater. After the reaction, ethyl acetate and water were added, and liquid separation washing was performed 5 times. After distilling off the solvent from the remaining resin solution under reduced pressure, vacuum drying was carried out to obtain 79.5 g of resorcinol calixarene powder (a-1) in the form of a pale red powder.

[0061] (Synthesis Example 2) Resorcinol calixarene powder (a-2) 76.8 g was obtained in the same manner as in Synthesis Example 1, except that decyl aldehyde was changed to hexyl aldehyde (0.34 mol: manufactured by Kao Chemicals, aliphatic aldehyde with 6 carbon atoms).

[0062] (Synthesis Example 3) Resorcinol calixarene powder (a-3) 76.1 g was obtained in the same manner as in Synthesis Example 1, except that decyl aldehyde was changed to propionaldehyde (0.34 mol: manufactured by Kao Chemicals, aliphatic aldehyde with 3 carbon atoms).

[0063] (Synthesis Example 4) Resorcinol calixarene powder (a-4) 77.3 g was obtained in the same manner as in Synthesis Example 1, except that decyl aldehyde was changed to benzaldehyde (0.34 mol: manufactured by Fuji Film Wako Pure Chemical Industries, aromatic aldehyde with 7 carbon atoms).

[0064] [Production and Evaluation of Surface-Modified Carbon Black and Dispersions] (Example 1) In a 500 ml four-necked flask equipped with a cooling tube, 0.6 g of resorcinocalixarene powder (a-1), 60 g of carbon black powder (b-1) produced by the furnace method (Mitsubishi Chemical Corporation: #3350B (primary particle size of about 20 nm)), 12.0 g of a double bond-containing polymerizable monomer (c-1) (styrene), 0.02 g of benzoyl peroxide, and 108.4 g of toluene were charged, and the mixture was stirred and reacted under reflux at 70 °C for 4 hours using a mantle heater. After the reaction, methanol and water were added to precipitate the solid content, and the operation of removing the supernatant was repeated three times for washing. After distilling off the solvent from the remaining solid content solution under reduced pressure, vacuum drying was performed to obtain 67.3 g of a black surface-modified carbon black powder (A-1). 20 g of the surface-modified carbon black powder (A-1) obtained above and 180 g of N-methylpyrrolidone as a dispersion medium were mixed, and a carbon black dispersion (B-1) was obtained by performing a dispersion treatment with an ultrasonic homogenizer (manufactured by Yamato Scientific Co., Ltd.: LUH300) for 10 minutes.

[0065] (Example 2) Except that resorcinocalixarene powder (a-2) was used instead of resorcinocalixarene powder (a-1), 68.4 g of a black surface-modified carbon black powder (A-2) was obtained in the same manner as in Example 1. For the obtained surface-modified carbon black powder (A-2), a carbon black dispersion (B-2) was obtained in the same manner as in Example 1.

[0066] (Example 3) Except that resorcinocalixarene powder (a-3) was used instead of resorcinocalixarene powder (a-1), 67.4 g of a black surface-modified carbon black powder (A-3) was obtained in the same manner as in Example 1. For the obtained surface-modified carbon black powder (A-3), a carbon black dispersion (B-3) was obtained in the same manner as in Example 1.

[0067] (Example 4) Except for using resorcin[4]arene powder (a-4) instead of resorcin[4]arene powder (a-1), in the same manner as in Example 1, 68.3 g of black surface-modified carbon black powder (A-4) was obtained. For the obtained surface-modified carbon black powder (A-4), in the same manner as in Example 1, a carbon black dispersion (B-4) was obtained.

[0068] (Example 5) Except for using carbon black powder (b-2) produced by the acetylene method (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.: acetylene black (primary particle diameter of about 40 nm)) as the carbon black powder, in the same manner as in Example 1, 66.9 g of black surface-modified carbon black powder (A-5) was obtained. For the obtained surface-modified carbon black powder (A-5), in the same manner as in Example 1, a carbon black dispersion (B-6) was obtained.

[0069] (Example 6) Except for using a double bond-containing polymerizable monomer as methyl methacrylate (c-2), in the same manner as in Example 1, 68.0 g of black surface-modified carbon black powder (A-6) was obtained. For the obtained surface-modified carbon black powder (A-6), in the same manner as in Example 1, a carbon black dispersion (B-6) was obtained.

[0070] (Comparative Example 1) Except for not using resorcin[4]arene powder (a-1), in the same manner as in Example 1, 68.9 g of black surface-modified carbon black powder (A-7) was obtained. For the obtained surface-modified carbon black powder (A-7), in the same manner as in Example 1, a carbon black dispersion (B-7) was obtained.

[0071] (Comparative Example 2) 60 g of the same carbon black powder (b-1) as in Example 1, 1800 g of sulfolane, and 5 g of sulfamic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were mixed, and an agglomerated particle stirring reaction was carried out at 140 °C for 5 hours to treat the surface of the carbon black. After the reaction, the surface-treated carbon black was washed several times with an excess of the solvent, then poured into water, and the precipitate was filtered. After that, a surface-treated carbon black powder (A-8) was obtained by vacuum drying. Regarding the obtained surface-treated carbon black powder (A-8), a carbon black dispersion (B-8) was obtained in the same manner as in Example 1.

[0072] (Evaluation of dispersibility) Regarding a part of the carbon black dispersions prepared in Examples 1 to 6 and Comparative Examples 1 and 2, on the day of preparation, the concentration was adjusted to 0.1 to 0.5 kg / cm using N-methylpyrrolidone as the dispersion medium. 3 It was diluted. For this carbon black dispersion, the average particle diameter of the particles in the dispersion was measured using a heterodyne laser Doppler type particle size distribution measuring device (manufactured by Microtrac, UPA model 9340). The value of 50% cumulative frequency (Dupa50%) was taken as the average particle diameter. When the average particle diameter was less than 200 nm, the dispersibility was considered good (〇), and when the average particle diameter was 200 nm or more, the dispersibility was considered poor (×). The results are shown in Table 1.

[0073] (Evaluation of dispersion stability) Regarding the carbon black dispersions of the above examples, when 4 weeks had passed since the preparation date, the average particle diameter was measured under the same conditions as described above, and the change in the average particle diameter was evaluated. When the change in the average particle diameter was less than +10%, the dispersion stability was considered good (〇), and when the change in the average particle diameter was +10% or more, the dispersion stability was considered poor (×). The results are shown in Table 1.

[0074]

Table 1

[0075] From Table 1, it can be seen that the dispersion containing surface-modified carbon black obtained by polymerizing a double bond-containing polymerizable monomer in the presence of carbon black and a calixarene compound has excellent dispersibility and dispersion stability regardless of the difference in the molecular structure derived from the aldehyde compound in the calixarene compound (Examples 1 to 4), and also regardless of the type of carbon black and the double bond-containing polymerizable monomer (Examples 5 to 6). Also, from Table 1, it can be seen that the dispersion containing surface-modified carbon black obtained by polymerizing a double bond-containing polymerizable monomer in the presence of carbon black without the calixarene compound has poor dispersibility and dispersion stability (Comparative Example 1). Also, it can be seen that the dispersion simply treated with a surface treatment agent for carbon black also has poor dispersibility and dispersion stability (Comparative Example 2).

[0076] [Preparation and Evaluation of Black Resist Composition] (Example 7) Into a 10 ml screw tube, 3 g of the carbon black dispersion (B-1) obtained in Example 1, 0.07 g of dipentaerythritol hexaacrylate, 0.52 g of an acid anhydride polycondensate of epoxy acrylate having a fluorene skeleton as an alkali-soluble resin (solid content 56 mass%, V259ME manufactured by Nippon Steel Chemical Co., Ltd.), 0.03 g of the photopolymerization initiator Irgacure OXE02 (manufactured by BASF Japan Ltd.), and 1.39 g of propylene glycol monomethyl ether acetate were added and stirred with a magnetic stirrer for 10 minutes to obtain a black resist composition (C-1). The carbon black content in the black resist composition is 6 mass%.

[0077] (Examples 8 to 12, Comparative Examples 3, 4) Black resist compositions (C-2) to (C-8) were prepared in the same manner as in Example 7, except that the carbon black dispersions (B-2) to (B-8) obtained in Examples 2 to 6 and Comparative Examples 1 and 2 were used respectively.

[0078] [Evaluation of Film-Forming Property of Coating Film] The black resist compositions obtained in Examples 7 to 12 and Comparative Examples 3 and 4 were applied onto a 150 mm × 150 mm glass using a spin coater so that the film thickness after drying was 1 μm, and this was dried on a hot plate at a surface temperature of 90°C for 1 minute to form a coating film. The film-forming property of the obtained coating film was evaluated. A film having gloss and no unevenness was regarded as having good film-forming property (〇), and a film having no gloss or unevenness was regarded as having poor film-forming property (×). The results are shown in Table 2.

[0079] [Table 2]

[0080] From Table 2, it can be seen that the black resist composition containing the carbon black dispersion of the present invention is excellent in coating film-forming property (Examples 7 to 12).

Claims

1. A polymer of a double bond-containing polymerizable monomer is present on part or all of the surface of carbon black, and the polymer of the double bond-containing polymerizable monomer contains a calixarene compound. The surface-modified carbon black, wherein the calixarene compound is a compound represented by the following formula (1). 【Chemical Formula 3】 (In the formula, R1 is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group. R2 and R3 are each independently a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, or an aralkyl group. n is an integer of 3 to 6.)

2. The aforementioned R １ The surface-modified carbon black according to claim 1, wherein R is a phenyl group or an alkyl group having 2 to 10 carbon atoms.

3. The surface-modified carbon black according to claim 1, wherein the double bond-containing polymerizable monomer is at least one selected from styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, acrylonitrile, methacrylonitrile, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, glycidyl (meth)acrylate and glycidyl vinyl ether, hydroxyethyl (meth)acrylate, hydroxybutyl (meth)acrylate, 4-vinylcyclohexene 1,2-epoxide, epoxycyclohexenyl (meth)acrylate, 2-oxetanylpropyl (meth)acrylate, ethylene glycol di(meth)acrylate and 1,3-butylene glycol di(meth)acrylate.

4. The surface-modified carbon black according to claim 3, wherein the double bond-containing polymerizable monomer is at least one selected from styrene compounds, acrylates and methacrylates.

5. A carbon black dispersion comprising the surface-modified carbon black according to any one of claims 1 to 4 and a dispersion medium.

6. A black resist composition comprising the surface-modified carbon black according to any one of claims 1 to 4.

7. A cured film of the black resist composition according to claim 6.

8. A method for producing surface-modified carbon black, comprising the step of preparing a mixture containing (A) carbon black, (B) a calixarene compound, (C) a double bond-containing polymerizable monomer, (D) a solvent and (E) a polymerization initiator, and polymerizing the (C) double bond-containing polymerizable monomer. The (B) calixarene compound is a compound represented by the following formula (1). A method for producing surface-modified carbon black. 【Chemical Formula 4】 (In the formula, R1 is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group. R2 and R3 are each independently a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, or an aralkyl group. n is an integer of 3 to 6.)

9. Said R １ The production method according to claim 8, wherein R is a phenyl group or an alkyl group having 2 to 10 carbon atoms.

10. The production method according to claim 8 or 9, wherein the (C) double bond-containing polymerizable monomer is at least one monomer selected from styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, acrylonitrile, methacrylonitrile, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, glycidyl (meth)acrylate and glycidyl vinyl ether, hydroxyethyl (meth)acrylate, hydroxybutyl (meth)acrylate, 4-vinylcyclohexene 1,2-epoxide, epoxycyclohexenyl (meth)acrylate, 2-oxetanylpropyl (meth)acrylate, ethylene glycol di(meth)acrylate and 1,3-butylene glycol di(meth)acrylate.

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