Black dispersion, UV-curable black composition, black cured film, black matrix for color filter, color filter, partition material, display device, light-shielding film for solid-state imaging device, solid-state imaging device

Abstract

To provide a black dispersion liquid having good storage stability in a high humidity environment. [Solution] This black dispersion contains a solvent, a black pigment, and a polymeric dispersant, wherein the black pigment contains zirconium nitride, and the polymeric dispersant contains a comb polymer, wherein the comb polymer has a main chain, a first end group bonded to a first end of the main chain, and a second end group bonded to a second end of the main chain opposite the first end, wherein the main chain has a first repeating unit having a structure derived from maleic acid or a structure derived from a condensate of maleic acid, and a second repeating unit having a group containing a polyethylene oxide structure, and wherein the first end group and the second end group are each selected from a carboxyl group and an alkyl group.

Description

[Technical Field]

[0001] The present invention relates to a black dispersion, an ultraviolet-curable black composition, a black cured film, a black matrix for a color filter, a color filter, a partition material, a display device, a light-shielding film for a solid-state imaging device, and a solid-state imaging device. [Background technology]

[0002] Conventionally, ultraviolet-curable black compositions have been used as materials for black films such as black matrices for color filters in displays. The ultraviolet-curable black compositions contain a black dispersion liquid containing a black pigment, an ultraviolet-curable organic substance, and a photopolymerization initiator. Carbon black is generally used as a black pigment. It has also been proposed to use zirconium nitride as a black pigment for use in a black matrix for a color filter. For example, Patent Document 1 describes such a zirconium nitride.

[0003] Patent Document 1 describes a method for producing a sintered body having a specific surface area of ​​20 to 90 m2 measured by the BET method. 2 / g, and in an X-ray diffraction profile, it has a zirconium nitride peak but does not have a zirconium dioxide peak or a peak for low-order zirconium oxide, and in the transmission spectrum of a dispersion liquid with a powder concentration of 50 ppm, the light transmittance X at 370 nm is at least 18% and the light transmittance Y at 550 nm is 12% or less, and the ratio of the light transmittance X at 370 nm to the light transmittance Y at 550 nm (X / Y) is 2.5 or more.

[0004] Patent Document 2 also describes a black dispersion containing a solvent, a black pigment containing zirconium nitride, and a polymer dispersant, and an ultraviolet-curable black composition containing a black dispersion, an ultraviolet-curable organic substance, and a photopolymerization initiator. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6591948 [Patent Document 2] Japanese Patent Application Publication No. 2023-65891 Summary of the Invention [Problem to be solved by the invention]

[0006] However, carbon black, which is generally used as a black pigment, has low ultraviolet transmittance. Therefore, if a sufficient amount of carbon black is contained in an ultraviolet-curable black composition to obtain a black cured film with high light-blocking properties, it becomes difficult to cure the composition with ultraviolet light. This is because the carbon black blocks ultraviolet light, resulting in insufficient curing of the ultraviolet-curable organic material contained in the ultraviolet-curable black composition.

[0007] To solve this problem, it has been considered to use zirconium nitride as a black pigment. Zirconium nitride has the ability to block visible light (550 nm) and has excellent ultraviolet transmittance. Therefore, an ultraviolet-curable black composition containing zirconium nitride as a black pigment can be cured by ultraviolet light even if it contains a sufficient amount of zirconium nitride to obtain a black cured film with high light-blocking properties. Therefore, a black cured film containing a sufficient amount of black pigment can be formed by a method of curing using ultraviolet light.

[0008] However, a black dispersion containing zirconium nitride, which is used as a raw material for an ultraviolet-curable black composition containing zirconium nitride, has a problem in that it has insufficient storage stability in a high-humidity environment.

[0009] The present invention has been made in view of the above circumstances, and has an object to provide a black dispersion liquid that has good storage stability in a high humidity environment. Another object of the present invention is to provide an ultraviolet-curable black composition containing the black dispersion of the present invention, and a black cured film that is a cured product of the ultraviolet-curable black composition of the present invention. Another object of the present invention is to provide a black matrix for a color filter, a color filter, a partition wall material, a display device, a light-shielding film for a solid-state imaging device, and a solid-state imaging device, each of which includes the black cured film of the present invention. [Means for solving the problem]

[0010] [1] A coating composition comprising a solvent, a black pigment, and a polymer dispersant, The black pigment comprises zirconium nitride, the polymeric dispersant comprises a comb polymer having a backbone, a first end group attached to a first end of the backbone, and a second end group attached to a second end of the backbone opposite the first end; the main chain has a first repeating unit having a structure derived from maleic acid or a structure derived from a condensate of maleic acid, and a second repeating unit having a group containing a polyethylene oxide structure, The black dispersion liquid, wherein the first terminal group and the second terminal group are each selected from a carboxyl group and an alkyl group.

[0011] [2] The black dispersion according to [1], wherein the comb polymer is a polymer represented by the following general formula (I): [ka] (In general formula (I), the first terminal group and the second terminal group are each selected from a carboxyl group and an alkyl group. R 1 -H and R 2 -H is either a carboxyl group or an alkyl group. 3 is any one selected from a carboxyl group, an alkyl group, and a hydrogen atom. α, β, and n represent the number of repeating units, α being 5 to 20, β being 5 to 75, and n being 2 to 60. The repeating unit having the number of repeating units α is the first repeating unit, and the repeating unit having the number of repeating units β is the second repeating unit.

[0012] [3] An ultraviolet-curable black composition comprising the black dispersion liquid according to [1] or [2], an ultraviolet-curable organic substance, and a photopolymerization initiator.

[0013] [4] The ultraviolet-curable black composition according to [3], wherein the ultraviolet-curable organic material contains a monomer or oligomer having an ethylenically unsaturated bond. [5] The ultraviolet-curable black composition according to [3] or [4], wherein the ultraviolet-curable organic material contains a monomer or oligomer having a (meth)acryloyl group and a carboxyl group.

[0014] [6] A black cured film which is a cured product of the ultraviolet-curable black composition according to any one of [3] to [5]. [7] A black matrix for a color filter, comprising the black cured film according to [6]. [8] A color filter comprising the black matrix for a color filter according to [7].

[0015] [9] A partition wall material comprising the black cured film described in [6].

[10] A display device comprising the partition material according to [9].

[11] A light-shielding film for a solid-state imaging device, comprising the black cured film according to [6].

[12] A solid-state imaging device comprising the light-shielding film for a solid-state imaging device according to

[11] . [Effects of the Invention]

[0016] A black dispersion according to one embodiment of the present invention includes a solvent, a black pigment, and a polymeric dispersant. The black pigment contains zirconium nitride. The polymeric dispersant contains a comb polymer. The comb polymer has a main chain, a first end group attached to a first end of the main chain, and a second end group attached to a second end of the main chain opposite the first end. The main chain has a first repeating unit having a structure derived from maleic acid or a structure derived from a condensate of maleic acid, and a second repeating unit having a group containing a polyethylene oxide structure. The first end group and the second end group are each selected from a carboxyl group and an alkyl group. This results in a black dispersion with good storage stability even in high-humidity environments. DETAILED DESCRIPTION OF THE INVENTION

[0017] The black dispersion, ultraviolet-curable black composition, black cured film, black matrix for color filters, color filters, partition materials, display devices, light-shielding films for solid-state imaging devices, and solid-state imaging devices of the present invention will be described in detail below. The scope of the present invention is not limited to the embodiment described herein, and various modifications can be made without departing from the spirit (technical requirements) of the present invention. Furthermore, when multiple upper and lower limit values ​​are listed for a specific parameter, any of these upper and lower limit values ​​can be combined to form a suitable numerical range.

[0018] [Black dispersion] The black dispersion of this embodiment contains a solvent, a black pigment, and a polymer dispersant.

[0019] (solvent) Examples of solvents contained in the black dispersion liquid of this embodiment include glycol ethers such as ethyl carbitol, ethyl carbitol acetate, butyl carbitol acetate (BCA), butyl carbitol, methyl cellosolve, ethyl cellosolve, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether. Examples of the solvent include methyl methyl ketone (MEK), 3-methoxy-3-methyl-1-butanol, tetrahydrofuran, α-terpineol, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone, ethyl acetate, butyl acetate, n-propanol, isopropanol, methanol, ethanol, n-butanol, isobutanol, toluene, xylene, cyclohexanone, cyclohexane, methylcyclohexane, normal hexane, isohexane, mineral spirits, N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), isophorone, γ-butyrolactone, and diacetone alcohol. Only one solvent may be used, or two or more solvents may be used.

[0020] When the amount of the black dispersion is taken as 100 parts by mass, the content of the solvent contained in the black dispersion can be, for example, in the range of 40 parts by mass to 99 parts by mass. The content of the solvent contained in the black dispersion can be appropriately determined depending on the application, type, and molecular weight of the polymer dispersant, and the physical properties of the black dispersion, such as the viscosity, and is not particularly limited.

[0021] (black pigment) The black pigment is dispersed as black particles in the black dispersion. The black particles contained in the black dispersion of this embodiment contain zirconium nitride. The black particles preferably contain 80 mass% or more, more preferably 90 mass% or more, of zirconium nitride. The black particles may be zirconium nitride particles composed of zirconium nitride and inevitable impurities. The black particles may contain oxygen together with zirconium nitride within a range that does not impair the properties of the black pigment. Furthermore, the black particles may contain metal elements other than zirconium together with zirconium nitride within a range that does not impair the properties of the black pigment.

[0022] Zirconium nitride particles can be produced, for example, by a method (thermit process) in which zirconium oxide powder is reacted with nitrogen gas in the presence of a reducing agent to reduce it. For example, metallic magnesium powder can be used as the reducing agent. Alternatively, a metallic magnesium powder to which magnesium oxide powder has been added may be used as the reducing agent. Zirconium nitride particles produced using metallic magnesium as the reducing agent contain magnesium as an inevitable impurity. The magnesium content of the zirconium nitride particles may be in the range of 0.1% by mass to 5.0% by mass.

[0023] Alternatively, the zirconium nitride particles may be produced by a method (plasma synthesis method) in which metallic zirconium particles and / or zirconium oxide particles are reduced in a nitrogen gas atmosphere using a plasma nanoparticle production device. By using the plasma synthesis method, high-purity zirconium nitride particles can be obtained.

[0024] The black pigment may contain a compound in which part of the zirconium contained in zirconium nitride is partially substituted (doped) with another element, as needed, to change the optical performance and / or particle shape. Elements that can be doped into zirconium nitride include titanium, niobium, vanadium, yttrium, hafnium, iron, zinc, aluminum, carbon, boron, and lanthanoids.

[0025] The black particles contained in the black dispersion as the black pigment may be of only one type or may be of two or more types. When two or more types of black particles are contained, for example, the black particles may be of two or more types having different zirconium nitride contents, or may contain black particles containing zirconium nitride and black particles not containing zirconium nitride.

[0026] Known black particles can be used as black particles that do not contain zirconium nitride, and examples thereof include carbon black, titanium black, iron oxide, manganese oxide, perylene black, lactam black, and mixtures thereof. When black particles that do not contain zirconium nitride are contained in the black pigment, the content of the black particles that do not contain zirconium nitride is set within a range that does not impair the properties of the black dispersion of this embodiment. For example, the content is preferably within a range of 20 parts by mass or less, and more preferably within a range of 10 parts by mass or less, per 100 parts by mass of the black particles that contain zirconium nitride.

[0027] The average particle diameter of the black pigment may be 500 nm or less. The average particle diameter of the black pigment is more preferably in the range of 10 nm or more and 400 nm or less, and particularly preferably in the range of 10 nm or more and 300 nm or less. The average particle diameter of the black pigment is the BET diameter calculated from the BET specific surface area value measured by the BET method and the density, using the following formula (1) assuming the particle shape to be spherical. In formula (1), L is the average particle diameter (m) of the black pigment, and ρ is the true density (g / m) of the black pigment. 3 ), S is the BET specific surface area of ​​the black pigment (m 2 / g). The BET specific surface area value can be measured by the BET single-point method using nitrogen adsorption, for example, using a specific surface area measuring device (SA-1100, manufactured by Shibata Scientific Co., Ltd.). L = 6 / (ρ × S) (1)

[0028] When the amount of the black dispersion is 100 parts by mass, the content of the black pigment contained in the black dispersion is preferably in the range of 1 part by mass to 50 parts by mass. When the content of the black pigment is 1 part by mass or more, curing the ultraviolet-curable black composition containing the black dispersion of this embodiment makes it easier to obtain a black cured film with high light-blocking properties. Furthermore, when the content of the black pigment is 50 parts by mass or less, the black pigment can be more stably dispersed in the black dispersion. The content of the black pigment contained in the black dispersion is more preferably in the range of 5 parts by mass to 45 parts by mass, and particularly preferably in the range of 10 parts by mass to 40 parts by mass.

[0029] (polymer dispersant) The polymer dispersant contained in the black dispersion liquid of this embodiment has a polyethylene oxide structure (-(O-CH2CH2) n The black pigment dispersion contains one or more comb polymers having a carboxyl group (-COOH). The comb polymers have excellent hydrophilicity due to their polyethylene oxide structure, allowing the black pigment to be stably dispersed in the black dispersion. The carboxyl groups of the comb polymers also reduce the elution of basic components derived from zirconium nitride.

[0030] The comb polymer contained in the polymeric dispersant has a main chain, a first end group attached to a first end of the main chain, and a second end group attached to a second end of the main chain opposite the first end. The main chain of the comb polymer consists of a first repeating unit having a structure derived from maleic acid (-C(-COOH)HC(-COOH)H-) or a structure derived from a condensation product of maleic acid, and a polyethylene oxide structure (-(O-CH2CH2) n and a second repeat unit having a group containing -).

[0031] When the main chain of the comb polymer has a plurality of first repeating units, all of the first repeating units may have a structure derived from maleic acid, all of the first repeating units may have a structure derived from a condensate of maleic acid, or the comb polymer may include a first repeating unit having a structure derived from maleic acid and a first repeating unit having a structure derived from a condensate of maleic acid.

[0032] When the main chain of the comb polymer has a plurality of second repeating units, the polyethylene oxide structure (-(O-CH2CH2) n The number of -) may be different from one another, or some or all of them may be the same. It is preferable that the number of polyethylene oxide structures contained in the plurality of second repeating units is the same, as this results in a comb polymer that is easy to produce.

[0033] There are no particular restrictions on the arrangement order of the first repeating units and the second repeating units, i.e., the comb polymer may be any of a random copolymer, a block copolymer, and an alternating copolymer composed of the first repeating units and the second repeating units.

[0034] The ratio of the number of second repeating units to the number of first repeating units is determined by the ratio of the number of polyethylene oxide structures (-(O-CH2CH2) n The number of repeating units (-) can be appropriately determined depending on the application of the black dispersion, etc. The ratio of the number of second repeating units to the number of first repeating units can be, for example, 1 to 15, and more preferably 5 to 10. When the ratio of the number of second repeating units to the number of first repeating units is 15 or less, the number of carboxyl groups contained in the comb polymer is sufficiently large. Therefore, the comb polymer contained in the black dispersion can more effectively reduce the elution of basic components derived from zirconium nitride contained in the black pigment. Furthermore, when the ratio of the number of second repeating units to the number of first repeating units is 1 or more, the inclusion of the comb polymer in the black dispersion improves hydrophilicity and provides better storage stability.

[0035] The main chain of the comb polymer may contain not only the first repeating unit and the second repeating unit, but also, if necessary, one or more third repeating units that are not the first repeating unit or the second repeating unit. Examples of the third repeating unit include a repeating unit derived from methylstyrene.

[0036] The ratio of the number of third repeating units to the total number of first repeating units and second repeating units is preferably 10 or less, more preferably 5 or less. When the main chain of the comb polymer contains a third repeat unit, there are no particular restrictions on the arrangement order of the first repeat unit, the second repeat unit, and one or more third repeat units.

[0037] The first terminal group and the second terminal group are each selected from a carboxyl group (—COOH) and an alkyl group. When the first terminal group and the second terminal group are alkyl groups, the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and may be linear or branched. Specific examples of the alkyl group when the first terminal group and the second terminal group are alkyl groups include a methyl group (-CH3), an ethyl group (-CH2CH3), and an n-propyl group (-CH2CH2CH3). When the first end group and the second end group are both carboxyl groups, the comb polymer can more effectively reduce the elution of base components derived from zirconium nitride contained in the black pigment.

[0038] The comb polymer contained in the polymer dispersant is preferably a polymer represented by the following general formula (I).

[0039] [ka] In general formula (I), the first terminal group and the second terminal group are each selected from a carboxyl group and an alkyl group. 1 -H and R 2-H is either a carboxyl group or an alkyl group. 3 is any one selected from a carboxyl group, an alkyl group, and a hydrogen atom. α, β, and n represent the number of repeating units, with α being 5 to 20, β being 5 to 75, and n being 2 to 60. The repeating unit having the number of repeating units α is the first repeating unit, and the repeating unit having the number of repeating units β is the second repeating unit. There are no particular restrictions on the arrangement order of the repeating units. The comb polymer represented by formula (I) may be any of a random copolymer, a block copolymer, and an alternating copolymer.

[0040] The comb polymer represented by general formula (I) can also be represented by the following general formula (II):

[0041] [ka]

[0042] R in formula (II) 1 , R 2 , R 3 , α, β, and n are R in formula (I). 1 , R 2 , R 3 , α, β, and n are the same. In formula (II), the number of repeating units having the same molecular structure as the first repeating unit of formula (I) is α, and the number of repeating units having the same molecular structure as the second repeating unit of formula (I) is β.

[0043] In formulas (I) and (II), R 1 -H and R 2 -H is either a carboxyl group (-COOH) or an alkyl group. 1 and R 2 It can also be said that each of R is selected from an ester bond (—COO—) and an alkylene group. 1 and one end of the second repeat unit is R 2 The third terminal group, R 3is any one selected from a carboxyl group, an alkyl group, and a hydrogen atom. 1 -H, R 2 -H, R 3 When either of the first and second terminal groups is an alkyl group, examples of the alkyl group include the same alkyl groups as those when the first and second terminal groups are alkyl groups. R, which is the first terminal group, the second terminal group, and the third terminal group 3 may be different groups, or some or all of them may be the same group.

[0044] One of the first and second terminal groups is R 1 -H and the other is R 2 Preferably it is —H. R 1 Preferably, -H is an alkyl group, most preferably a methyl group. R 2 Preferably, —H is a carboxyl group. The third terminal group, R 3 is preferably a methyl group or a hydrogen atom, and most preferably a hydrogen atom.

[0045] As described above, the first end group and the second end group are each selected from a carboxyl group and an alkyl group. Therefore, even if the first end group and the second end group are the same, the effects of the present invention can be obtained. For example, when the comb polymer is a random copolymer, both the first end group and the second end group of the comb polymer are R 1 -H, or both the first and second end groups of the comb polymer may be R 2 -H may also be used. One end of the first repeating unit is R 1 and the other end of the first repeat unit is CH. One end of the second repeat unit is R 2and the other end of the second repeating unit is CH2. When the comb polymer is a random copolymer and the other end CH of the first repeating unit is located at the end of the comb polymer, H is attached to the other end CH of the first repeating unit to form CH2, and the first end group or the second end group is CH2. In this case, it does not become a comb polymer of this embodiment. When the comb polymer is a random copolymer and the other end CH2 of the second repeating unit is located at the end of the comb polymer, H is attached to the other end CH2 of the second repeating unit to form CH3, and either the first end group or the second end group is CH3. In this case, the other of the first end group or the second end group is CH where H is attached to the other end CH2 of the second repeating unit. 3、 R 1 -H or R 2 -H, the comb polymer of this embodiment is obtained. When the comb polymer is a random copolymer, the first and second end groups of the comb polymer are CH2, where H is attached to the other end CH2 of the second repeating unit. 3、 R 1 -H or R 2 -H.

[0046] In formulae (I) and (II), α, which indicates the number of first repeating units, is 5-20, and preferably 10-15. In formulae (I) and (II), β, which indicates the number of second repeating units, is 5-75, and preferably 10-60. In the formulae (I) and (II), n, which indicates the number of polyethylene oxide structures, is 2-60, and preferably 2-50. When α, β, and n in formulas (I) and (II) are within the above ranges, the number of carboxyl groups is sufficiently large, the hydrophilicity is improved, and the comb polymer has an appropriate molecular weight.

[0047] The number-average molecular weight (Mn) of the comb polymer determined by gel permeation chromatography (GPC) is, for example, preferably 500 to 20,000, and more preferably 1,000 to 10,000. When the number-average molecular weight (Mn) of the comb polymer is 500 or more, the main chain length of the comb polymer is likely to be sufficiently long. This makes it easier for the comb polymer to form steric hindrance between the black pigment particles, further improving the dispersion stability of the black pigment. Furthermore, when the number-average molecular weight (Mn) of the comb polymer is 20,000 or less, the comb polymer adsorbed to the surface of the black particles is less likely to detach from the black particles, further improving the storage stability of the black pigment.

[0048] (Method of manufacturing comb polymer) The comb polymer contained in the polymer dispersant can be produced by known methods. A preferred example of the comb polymer, the comb polymer represented by formula (I), can be produced, for example, by radical copolymerization of a monomer mixture containing a monomer having a structure that will become the first repeating unit and a monomer having a structure that will become the second repeating unit in the presence of a polymerization initiator. Hereinafter, the comb polymer represented by formula (I) is the same as the comb polymer represented by formula (II).

[0049] The polymerization method for producing the comb polymer represented by formula (I) may be bulk polymerization without using a solvent, or solution polymerization with a solvent, and is appropriately determined depending on the molecular weight of the comb polymer represented by formula (I) to be produced, etc.

[0050] Examples of the monomer containing the structure that becomes the first repeating unit include maleic acid and condensates of maleic acid. Furthermore, an example of a monomer containing a structure that will become the second repeating unit is α-allyl-ω-methoxypoly(oxyethylene). As the α-allyl-ω-methoxypoly(oxyethylene), one in which the number of polyethylene oxide structures corresponds to the number n in the comb polymer represented by formula (I) to be produced can be used.

[0051] Examples of polymerization initiators that can be used in producing the comb polymer represented by formula (I) include peroxides such as benzoyl peroxide, tert-butyl hydroperoxide, 2,2-bis(4,4-di-tert-butylperoxycyclohexyl)propane, 1,1,3,3-tetramethylbutyl hydroperoxide, di-tert-hexyl peroxide, dilauroyl peroxide, and dibenzoyl peroxide.

[0052] Solvents that can be used in producing the comb polymer represented by formula (I) include, for example, toluene, xylene, tetrahydrofuran, diethyl ether, tert-butyl methyl ether, n-hexane, cyclohexane, chloroform, and the like.

[0053] The numbers α and β of repeating units in formula (I) can be adjusted by appropriately changing polymerization conditions such as the molar ratio of the monomer containing the structure that will become the first repeating unit to the monomer containing the structure that will become the second repeating unit, which are contained in the monomer mixture that is the raw material for the comb polymer represented by formula (I), the amount of the monomer mixture used, and the amount of solvent used.

[0054] In addition, the first terminal group, the second terminal group, and the third terminal group of the comb polymer represented by formula (I) are R 3 can be obtained as desired by a method for making the end groups of the monomer containing the structure that will become the first repeating unit and the monomer containing the structure that will become the second repeating unit contained in the raw material monomer mixture desired.

[0055] When the polymer dispersant contains a polymer dispersant that is not a comb polymer, the content of the polymer dispersant that is not a comb polymer is set within a range that does not impair the properties of the black dispersion of this embodiment. For example, the content is preferably 5 parts by mass or less, and more preferably 3 parts by mass or less, per 100 parts by mass of the comb polymer.

[0056] The content of the polymer dispersant contained in the black dispersion is preferably in the range of 1 to 50 parts by mass per 100 parts by mass of the black pigment. When the content of the polymer dispersant is 1 part by mass or more per 100 parts by mass of the black pigment, the dispersibility of the black pigment is improved. When the content of the polymer dispersant is 50 parts by mass or less per 100 parts by mass of the black pigment, the content of the black pigment contained in the black dispersion is easily ensured, and by curing the UV-curable black composition containing the black dispersion of this embodiment, a black cured film with high light-blocking properties is easily obtained. The content of the polymer dispersant is more preferably in the range of 5 to 45 parts by mass, and particularly preferably in the range of 10 to 40 parts by mass.

[0057] The black dispersion of this embodiment may contain, in addition to the solvent, black pigment, and polymer dispersant, other additives as needed. Examples of other additives include rheology control agents such as surfactants and leveling agents. The additives may be used alone or in combination.

[0058] In the black dispersion of this embodiment, the Hansen solubility parameter (HSP value) of the surfaces of the black particles (black pigment particles) contained in the black dispersion is preferably in the range of 20 to 30, and more preferably in the range of 24 to 28. When the HSP value of the black particle surfaces is 20 or more, the hydrophilicity of the surfaces of the black particles contained in the black dispersion is sufficiently high, resulting in better storage stability in high humidity environments. Furthermore, when the HSP value of the black particle surfaces is 30 or less, the affinity for the solvent contained in the black dispersion is high, resulting in better storage stability.

[0059] The HSP value of the black particle surface contained in the black dispersion is a numerical value obtained as the HSP value in a state where the polymer dispersant is adsorbed on the black particle surface. Therefore, the HSP value of the black particle surface is a numerical value that is greatly influenced by the polymer dispersant contained in the black dispersion, and is governed by the properties of the polymer dispersant. The Hansen solubility parameter (HSP value) of the surface of the black particles contained in the black dispersion can be determined by the method described below.

[0060] (Method of manufacturing black dispersion liquid) The black dispersion of this embodiment can be produced, for example, by mixing a solvent, a black pigment, a polymer dispersant, and other additives as needed, and dispersing the resulting mixture using a dispersion treatment device. Examples of the dispersion treatment device that can be used include known devices such as a bead mill and an ultrasonic disperser.

[0061] The black dispersion of this embodiment contains a solvent, a black pigment, and a polymer dispersant, and the black pigment contains zirconium nitride. Zirconium nitride has the ability to block visible light (550 nm) and has excellent ultraviolet transmittance. Therefore, an ultraviolet-curable black composition containing the black dispersion of this embodiment can be cured by ultraviolet light even if it contains a high concentration of zirconium nitride.

[0062] Furthermore, the black dispersion of this embodiment contains a polymer dispersant in which the second repeating unit has a polyethylene oxide structure (-(O-CHCH) n Since the black dispersion of this embodiment contains a comb polymer having a group containing -), it has good hydrophilicity. Therefore, the black dispersion of this embodiment has good storage stability even in a high-humidity environment.

[0063] [UV curable black composition] The ultraviolet-curable black composition of this embodiment contains the black dispersion of this embodiment, an ultraviolet-curable organic substance, and a photopolymerization initiator. When the amount of the ultraviolet-curable black composition of the present embodiment is taken as 100 parts by mass, the content of the black pigment contained in the ultraviolet-curable black composition can be, for example, in the range of 0.1 parts by mass to 45 parts by mass, and preferably in the range of 0.1 parts by mass to 40 parts by mass.

[0064] (UV curable organic matter) The ultraviolet-curable organic material contained in the ultraviolet-curable black composition of this embodiment preferably contains an oligomer having an ethylenically unsaturated bond or a monomer having an ethylenically unsaturated bond. The oligomer having an ethylenically unsaturated bond or the monomer having an ethylenically unsaturated bond may be used alone or in combination of two or more.

[0065] The oligomer having an ethylenically unsaturated bond may be an acrylic oligomer having two or more (meth)acryloyl groups. The acrylic oligomer is a low-molecular-weight polymer obtained by polymerization of an acrylic monofunctional monomer. Examples of the acrylic oligomer include acrylic (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, and polyester (meth)acrylate.

[0066] The oligomer having an ethylenically unsaturated bond may be a commonly available oligomer having the structure exemplified above. Specifically, the Shiko series (manufactured by Mitsubishi Chemical Corporation), the EBERCRYL series (manufactured by Daicel-Allnex Corporation), the NK Oligo series (manufactured by Shin-Nakamura Chemical Co., Ltd.), and the Aronix series (manufactured by Toagosei Co., Ltd.) are preferably used.

[0067] As the monomer having an ethylenically unsaturated bond, for example, a (meth)acrylic monofunctional monomer, a (meth)acrylic bifunctional monomer, or an acrylic polyfunctional monomer having three or more (meth)acryloyl groups can be used.

[0068] Examples of (meth)acrylic monofunctional monomers include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, and phenyl (meth)acrylate. acrylate, phenoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, isoamyl acrylate, N,N-dimethylacrylamide, 4-acryloylmorpholine, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, (2-ethyl-2-methyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, and the like.

[0069] Examples of the (meth)acrylic bifunctional monomer include 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, ethylene oxide-modified bisphenol A di(meth)acrylate, and neopentyl triethylene glycol di(meth)acrylate.

[0070] Examples of acrylic polyfunctional monomers having three or more (meth)acryloyl groups include dipentaerythritol hexa(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and trimethylolpropane tri(meth)acrylate.

[0071] When the amount of the UV-curable organic material is taken as 100 parts by mass, the content of the oligomer having an ethylenically unsaturated bond or the monomer having an ethylenically unsaturated bond contained in the UV-curable organic material can be, for example, in the range of 1 part by mass to 99 parts by mass. When the content of the oligomer having an ethylenically unsaturated bond or the monomer having an ethylenically unsaturated bond is 1 part by mass or more, the UV-curable organic material exhibits good UV-curing properties. When the content of the oligomer having an ethylenically unsaturated bond or the monomer having an ethylenically unsaturated bond is 99 parts by mass or less, the UV-curable organic material can contain a sufficient amount of, for example, other UV-curable organic materials. The content of the oligomer having an ethylenically unsaturated bond or the monomer having an ethylenically unsaturated bond is more preferably in the range of 1.5 parts by mass to 95 parts by mass, and particularly preferably in the range of 2 parts by mass to 90 parts by mass.

[0072] The ultraviolet-curable organic material contained in the ultraviolet-curable black composition of the present embodiment may contain a monomer or oligomer other than a monomer having an ethylenically unsaturated bond or an oligomer having an ethylenically unsaturated bond. Specifically, the ultraviolet-curable organic material may contain, as another monomer or oligomer, a monomer or oligomer having a (meth)acryloyl group and a carboxyl group, for example. In this case, the black cured film obtained by curing the ultraviolet-curable black composition of the present embodiment becomes an alkali-soluble resin.

[0073] In this embodiment, the monomer or oligomer having a carboxyl group contained in the ultraviolet-curable organic material is considered to be a monomer or oligomer other than a monomer or oligomer having an ethylenically unsaturated bond. Therefore, a monomer or oligomer having a (meth)acryloyl group and a carboxyl group is considered to be a monomer or oligomer other than a monomer or oligomer having an ethylenically unsaturated bond.

[0074] Examples of monomers or oligomers having a (meth)acryloyl group and a carboxyl group include methacrylic acid, mono(2-acryloyloxyethyl) succinate, Cyclomer P series (manufactured by Daicel Allnex Corporation), Viscoat R-264 (manufactured by Osaka Organic Chemical Industry Ltd.), KS Resist 106 (manufactured by Osaka Organic Chemical Industry Ltd.), and Acrycure RD-F8 (manufactured by Nippon Shokubai Co., Ltd.) The monomers or oligomers having a (meth)acryloyl group and a carboxyl group may be used alone or in combination of two or more.

[0075] When the amount of the UV-curable organic material is taken as 100 parts by mass, the content of the monomer or oligomer having a (meth)acryloyl group and a carboxyl group contained in the UV-curable organic material can be, for example, in the range of 5 to 99 parts by mass. When the content of the monomer or oligomer having a (meth)acryloyl group and a carboxyl group is 5 parts by mass or more, a black cured film with better alkali solubility can be formed by curing the UV-curable black composition. Furthermore, when the content of the monomer or oligomer having a (meth)acryloyl group and a carboxyl group is 99 parts by mass or less, the UV-curable organic material can contain a sufficient amount of oligomer having an ethylenically unsaturated bond or monomer having an ethylenically unsaturated bond. This makes it easier to obtain a UV-curable black composition with better photocuring properties. The content of the monomer or oligomer having a (meth)acryloyl group and a carboxyl group is more preferably in the range of 10 to 95 parts by mass, and particularly preferably in the range of 15 to 90 parts by mass.

[0076] The ultraviolet-curable black composition may contain other monomers or oligomers as required, such as styrene-based monomers and cationically curable monomers. Examples of styrene-based monomers include styrene, vinyltoluene, and divinylbenzene.

[0077] Examples of the cationically curable monomer include epoxy compounds and oxetane compounds. The epoxy compound is not particularly limited as long as it has a reactive epoxy group. Examples of the epoxy compound include epoxy monomer, bisphenol A type epoxy, bisphenol F type epoxy, biphenyl type epoxy, biphenyl mixed type epoxy, naphthalene type epoxy, cresol novolac type epoxy, dicyclopentadiene type epoxy, trisphenolethane type epoxy, tetraphenolethane type epoxy, aliphatic epoxy, and alicyclic epoxy.

[0078] Specific examples of epoxy compounds include n-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, lauryl glycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, allyl glycidyl ether, ethylene glycol diglycidyl ether, resorcinol diglycidyl ether, polypropylene glycol glycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, 1,2;5,6-diepoxyhexahydroindane, 3',3'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 1,2-epoxy-4-vinylcyclohexane.

[0079] Examples of oxetane compounds include 2-ethylhexyloxetane, 3-ethyl-3-(hydroxymethyl)oxetane, 3-ethyl-3-(4-hydroxybutyloxymethyl)oxetane, 3-ethyl-3-[(phenoxy)methyl]oxetane, 3-ethyl-3-(hexyloxymethyl)oxetane, 3,3'-(oxybismethylene)bis(3-ethyloxetane), 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane, and (3-ethyl-3-oxetanyl) Examples include methyl methacrylate, 4,4'-bis[(3-ethyl-3-oxetanyl)methoxymethyl]biphenyl, bis[(3-ethyl-3-oxetanyl)methyl]isophthalate, 3-ethyl-3([3-ethyloxetan-3-yl]methoxy)methyloxetane, 1,6-bis(3-ethyl-3-oxetanylmethoxy)hexane, 1,3-bis[(3-ethyl-3-oxetanylmethoxy)methyl], and oligomers obtained by partially polymerizing these.

[0080] The ultraviolet-curable organic material may contain a solvent in addition to the above components, if necessary. The amount of solvent contained in the ultraviolet-curable organic material is the balance other than the above components. Examples of the solvent include glycol ethers such as ethyl carbitol, ethyl carbitol acetate, butyl carbitol acetate (BCA), butyl carbitol, methyl cellosolve, ethyl cellosolve, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether; Examples of the solvent include 3-methyl-1-butanol, tetrahydrofuran, α-terpineol, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone, ethyl acetate, butyl acetate, n-propanol, isopropanol, methanol, ethanol, n-butanol, isobutanol, toluene, xylene, cyclohexanone, cyclohexane, methylcyclohexane, normal hexane, isohexane, mineral spirits, N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), isophorone, γ-butyrolactone, and diacetone alcohol. Only one solvent may be used, or two or more solvents may be used.

[0081] The content of the UV-curable organic material contained in the UV-curable black composition of this embodiment can be, for example, within a range of 5 to 99 parts by mass per 100 parts by mass of the UV-curable black composition. When the content of the UV-curable organic material is 5 parts by mass or more per 100 parts by mass of the UV-curable black composition, a black cured film with better solvent resistance can be formed by curing the UV-curable black composition. When the content of the UV-curable organic material is 99 parts by mass or less per 100 parts by mass of the UV-curable black composition, the content of the black pigment contained in the UV-curable black composition is more likely to be ensured, and when the UV-curable black composition is cured, a black cured film with high light-blocking properties can be more easily obtained. The content of the UV-curable organic material is more preferably within a range of 10 to 95 parts by mass, and particularly preferably within a range of 15 to 90 parts by mass.

[0082] (Photopolymerization initiator) As the photopolymerization initiator, a compound capable of absorbing ultraviolet light, specifically light with a wavelength of 100 nm to 400 nm, and initiating a polymerization reaction can be preferably used. The photopolymerization initiator may be used alone or in combination of two or more. The photopolymerization initiator may be, for example, a radical generator or a photoacid generator. Examples of the photopolymerization initiator include acetophenone-based compounds, benzophenone-based compounds, benzoin ether-based compounds, triazine compounds, phosphine oxide-based compounds, sulfonium-based compounds, and organic peroxides.

[0083] Examples of acetophenone compounds include acetophenone, dimethylacetophenone, and 2-hydroxy-2-methylpropiophenone. Examples of the benzophenone-based compounds include benzophenone and 2-chlorobenzophenone. Examples of the benzoin ether compounds include benzoin and benzoin methyl ether.

[0084] Examples of the phosphine oxide compound include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide. Examples of sulfonium compounds include bis(4-tert-butylphenyl)iodonium hexafluorophosphate, triphenylsulfonium tetrafluoroborate, and tri-p-tolylsulfonium trifluoromethanesulfonate. Examples of organic peroxides include benzoyl peroxide and cumene peroxide.

[0085] The content of the photopolymerization initiator contained in the ultraviolet-curable black composition of this embodiment can be, for example, in the range of 0.5 parts by mass to 15 parts by mass relative to 100 parts by mass of the ultraviolet-curable organic material.

[0086] (polymerization inhibitor) The ultraviolet-curable black composition of this embodiment may contain a polymerization inhibitor, if necessary, to improve storage stability. Examples of polymerization inhibitors include phenol derivatives such as hydroquinone, hydroquinone monomethyl ether, and t-butylphenol; benzoquinone derivatives such as benzoquinone and 2-methyl-1,4-benzoquinone; nitro compounds such as dinitrobenzene and nitrophenol; nitroso compounds such as nitrosobenzene, phenyl-t-butylnitrone, N-nitrosophenylhydroxylamine ammonium, and N-nitrosophenylhydroxylamine aluminum salt; phenothiazine, iron(III) chloride, and sulfur. These polymerization inhibitors may be used alone or in combination of two or more.

[0087] When the ultraviolet-curable black composition contains a polymerization inhibitor, the content of the polymerization inhibitor in the ultraviolet-curable black composition may be within a range that does not inhibit curing when the ultraviolet-curable black composition is irradiated with ultraviolet light to cure it. For example .... For example, the content of the polymerization inhibitor in the ultraviolet-curable black composition may be within a range that does not inhibit curing when the ultraviolet-curable black composition is irradiated with ultraviolet light. For example, the content of the polymerization inhibitor in the ultraviolet-curable black composition may be within a range that does not inhibit curing when the ultraviolet-curable black composition is irradiated with ultraviolet light. For example, the content of the polymerization inhibitor in the ultraviolet-cur -4 Mass part or more 5.0×10-2 It is preferable that the amount is in the range of parts by mass or less.

[0088] (plasticizer) The ultraviolet-curable black composition of this embodiment may contain one or more plasticizers as needed. Examples of the plasticizer include phosphate ester plasticizers, phthalate ester plasticizers, aliphatic-basic ester plasticizers, aliphatic dibasic acid ester plasticizers, dihydric alcohol ester plasticizers, and oxyacid ester plasticizers.

[0089] Examples of phosphate ester plasticizers include tributyl phosphate and 2-ethylhexyl phosphate. Examples of phthalate ester plasticizers include dimethyl phthalate and dibutyl phthalate. Examples of aliphatic-basic ester plasticizers include butyl oleate and glycerin monooleate. Examples of aliphatic dibasic acid ester plasticizers include dibutyl adipate and di-2-ethylhexyl sebacate. Examples of dihydric alcohol ester plasticizers include diethylene glycol dibenzoate and triethylene glycol di-2-ethyl butyrate. Examples of oxyacid ester plasticizers include methyl acetylricinoleate and tributyl acetyl citrate.

[0090] When the ultraviolet-curable black composition contains a plasticizer, the content of the plasticizer in the ultraviolet-curable black composition is preferably, for example, in the range of 1 part by mass or more and 100 parts by mass or less per 100 parts by mass of the ultraviolet-curable organic material.

[0091] The ultraviolet-curable black composition of this embodiment may contain other additives in addition to the black dispersion of this embodiment, an ultraviolet-curable organic material, a photopolymerization initiator, a polymerization inhibitor that may be contained if necessary, and a plasticizer that may be contained if necessary. Examples of other additives include rheology control agents such as surfactants and leveling agents. One type of additive may be used alone, or multiple types may be used in combination.

[0092] (Method of manufacturing ultraviolet-curable black composition) The ultraviolet-curable black composition of this embodiment can be produced, for example, by mixing the black dispersion of this embodiment, an ultraviolet-curable organic material, a photopolymerization initiator, a polymerization inhibitor that may be contained as needed, a plasticizer that may be contained as needed, and other additives that may be contained as needed. The mixing method is not particularly limited, and mixing can be carried out using a mixing device such as a planetary mixer, a bead mill, or a three-roll mill.

[0093] The ultraviolet-curable black composition of the present embodiment includes the black dispersion of the present embodiment. The black dispersion of the present embodiment includes zirconium nitride as a black pigment, which has visible light blocking properties and excellent ultraviolet transmittance. Therefore, the ultraviolet-curable black composition of the present embodiment can be cured by ultraviolet light even if it contains zirconium nitride at a high concentration.

[0094] Here, the effect of the ultraviolet-curable black composition of this embodiment containing a monomer or oligomer having a (meth)acryloyl group and a carboxyl group as the ultraviolet-curable organic substance will be described. Conventionally, black cured films obtained by curing an ultraviolet-curable black composition containing a monomer or oligomer having a (meth)acryloyl group and a carboxyl group as an ultraviolet-curable organic material and zirconium nitride as a black pigment have sometimes failed to exhibit sufficient solvent resistance. For this reason, there has been a demand for improving the solvent resistance of black cured films.

[0095] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, they have found that the curing of a monomer or oligomer having a (meth)acryloyl group and a carboxyl group, which is contained in an ultraviolet-curable black composition containing zirconium nitride, is inhibited by zirconium nitride. More specifically, they have found that the curing of the monomer or oligomer is inhibited by the elution of a basic component derived from zirconium nitride.

[0096] The black dispersion of this embodiment contained in the ultraviolet-curable black composition of this embodiment contains a comb polymer as a polymeric dispersant. The comb polymer may have a carboxyl group at either or both of the first and second terminal groups, and the first repeating unit has a carboxyl group. Therefore, the black dispersion of this embodiment reduces the elution of basic components derived from zirconium nitride due to the comb polymer. Therefore, in an ultraviolet-curable black composition containing the black dispersion of this embodiment and an ultraviolet-curable organic material containing a monomer or oligomer having a (meth)acryloyl group and a carboxyl group, the curing of the monomer or oligomer is less likely to be inhibited by the elution of basic components derived from zirconium nitride.

[0097] Therefore, the ultraviolet-curable black composition of this embodiment can be cured by ultraviolet light even if it contains a monomer or oligomer having a (meth)acryloyl group and a carboxyl group as the ultraviolet-curable organic substance and zirconium nitride as the black pigment. Furthermore, a black cured film obtained by curing the ultraviolet-curable black composition of this embodiment, which contains a monomer or oligomer having a (meth)acryloyl group and a carboxyl group as the ultraviolet-curable organic substance and zirconium nitride as the black pigment, is alkali-soluble and has good solvent resistance and excellent durability.

[0098] [Black cured film] The black cured film of this embodiment is a cured product of the ultraviolet-curable black composition of this embodiment. Therefore, the black cured film of this embodiment can be efficiently produced by a method of irradiating ultraviolet light and can contain a sufficient amount of black pigment. Furthermore, when the black cured film of this embodiment is a cured product of an ultraviolet-curable black composition containing, for example, a monomer or oligomer having a (meth)acryloyl group and a carboxyl group, the black cured film has alkali solubility, good solvent resistance, and excellent durability.

[0099] The black cured film of this embodiment can be formed, for example, by the following method. First, the ultraviolet-curable black composition of this embodiment is applied to the surface on which the black cured film is to be formed to form a coating film. Next, the solvent in the coating film is volatilized and removed. Thereafter, the coating film is irradiated with ultraviolet light to polymerize and cure the ultraviolet-curable organic material contained in the ultraviolet-curable black composition.

[0100] The ultraviolet light source is not particularly limited as long as it has a wavelength that matches the absorption wavelength of the photopolymerization initiator contained in the ultraviolet-curable black composition. Examples of the light source that can be used include a halogen lamp, a metal halide lamp, and a UV-LED (ultraviolet light-emitting diode).

[0101] [Partition wall materials, black matrix for color filters, color filters, display devices] The partition wall material of this embodiment includes the black cured film of this embodiment. Examples of the partition wall material of this embodiment include black picture frames. Specific examples of the partition wall material include black matrices for color filters. Because the black matrix for color filters of this embodiment includes the black cured film of this embodiment, it can be efficiently produced by a method of irradiating ultraviolet light and can contain a sufficient amount of black pigment. Therefore, the black matrix for color filters, which is an example of the partition wall material of this embodiment, and color filters containing the same can be preferably used in display devices such as liquid crystal displays, organic EL displays, and touch panels.

[0102] As described above, the black cured film (partition wall material) of this embodiment can be efficiently produced by a method of irradiating ultraviolet light and can contain a sufficient amount of black pigment. Display devices such as liquid crystal displays, organic EL displays, and touch panels of this embodiment include this black cured film (partition wall material) of this embodiment. Therefore, the display devices of this embodiment have excellent productivity and good characteristics.

[0103] [Light-shielding film for solid-state imaging devices, solid-state imaging devices] The light-shielding film for a solid-state imaging device of this embodiment includes the black cured film of this embodiment. The light-shielding film for a solid-state imaging device of this embodiment can be efficiently produced by a method of irradiating ultraviolet light and can contain a sufficient amount of black pigment. Therefore, the light-shielding film for a solid-state imaging device of this embodiment can be preferably used as a light-shielding film used in solid-state imaging devices such as CMOS (Complementary Metal Oxide Semiconductor) image sensors.

[0104] As described above, the black cured film (light-shielding film for solid-state imaging devices) of this embodiment can be efficiently produced by a method of irradiating ultraviolet light and can contain a sufficient amount of black pigment. A solid-state imaging device such as a CMOS image sensor of this embodiment includes this black cured film (light-shielding film for solid-state imaging devices) of this embodiment. Therefore, the solid-state imaging device of this embodiment has excellent productivity and good characteristics.

[0105] Although the embodiment of the present invention has been described above, the present invention is not limited to this and can be modified as appropriate within the scope of the technical requirements of the invention. [Example]

[0106] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0107] [Production of black dispersion liquid] (Examples 1 to 17) The black dispersions of Examples 1 to 17 were produced by mixing the solvent shown in Table 1, the black pigment shown in Table 1, which is zirconium nitride particles produced by the method shown below, and the comb polymer represented by general formula (I) (Table 2), which serves as a polymer dispersant and is produced by the method shown below, in the ratios shown in Table 1, and dispersing the resulting mixture using a bead mill.

[0108] [Table 1]

[0109] [Table 2]

[0110] The solvents shown in Table 1 were as follows: (Solvent A) Propylene glycol monomethyl ether acetate (PGMEA) (Solvent B) α-terpineol

[0111] Pigment A and pigment B shown in Table 1 were produced using the methods described below. (Manufacturing method of pigment A (zirconium nitride particles)) Black particles containing zirconium nitride were produced by the thermite method. Specifically, 7.4 parts by mass of zirconium dioxide powder having an average primary particle size of 50 nm, 7.3 parts by mass of metallic magnesium powder having an average primary particle size of 150 μm, and 7.3 parts by mass of magnesium oxide powder were placed in a mortar and mixed using a pestle to obtain a mixture. The resulting mixture was fired at 700°C for 60 minutes in a nitrogen gas atmosphere using a reactor consisting of a quartz glass tube fitted with a graphite boat to obtain a fired product.

[0112] The resulting fired product was dispersed in water at a concentration of 20 g / L, and 10% aqueous hydrochloric acid was gradually added to prevent the pH of the resulting dispersion from becoming less than 1. The fired product was then acid-washed by stirring the dispersion while maintaining the temperature below 100°C. Next, 25% aqueous ammonia was added to the dispersion to adjust the pH to 7-8. The dispersion was then filtered to recover the solids. The recovered solids were redispersed in water at a concentration of 100 g / L, and once again subjected to acid washing, pH adjustment with aqueous ammonia, and filtration in the same manner as above. This acid washing and pH adjustment with aqueous ammonia were repeated twice. The filtrate was then dispersed in ion-exchanged water at a concentration of 500 g / L (solids equivalent), heated and stirred at 60°C, and adjusted to pH 7. The filtrate was then filtered using a suction filter. The filtrate was then washed with an equal amount of ion-exchanged water and dried in a hot air dryer at a set temperature of 120°C to obtain black particles containing zirconium nitride.

[0113] The obtained black particles had an average particle size (BET size) of 30 nm. The zirconium nitride content in the black particles was 99 mass %, with the remainder being unavoidable impurities including magnesium.

[0114] (Method of manufacturing pigment B (zirconium nitride particles)) Black particles containing zirconium nitride were produced by plasma synthesis. Specifically, 10 g of metallic zirconium powder (purity 99%, average primary particle size 20 μm) was fed into the raw material feeder of a high-frequency induction thermal plasma nanoparticle synthesis device (JEOL Ltd.: TP40020NPS). These raw materials were then introduced into a plasma torch and volatilized by thermal plasma generated by the plasma torch using a mixed gas of N2 and Ar. The volatilized raw materials were then quenched in a chamber through which N2 gas was circulating. This resulted in black particles containing zirconium nitride powder. The average particle size (BET diameter) of the resulting black particles was 30 nm.

[0115] Titanium Black (product name: 13M, manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.) was used as pigment C shown in Table 1. The average particle diameter (BET diameter) of pigment C was 90 nm.

[0116] The polymer dispersants shown in Table 2 were produced using the method described below. The content of the polymer dispersant (comb polymer) shown in Table 1 is the content (parts by mass) of the comb polymer relative to 100 parts by mass of the black dispersion.

[0117] (Method of producing polymer dispersants of Example 1, Examples 10 to 17) A mixed monomer containing maleic acid having the substituents shown in Table 3 and α-allyl-ω-methoxypoly(oxyethylene) having the substituents shown in Table 3 was mixed in toluene as a solvent, and then benzoyl peroxide was added as a photopolymerization initiator to carry out radical copolymerization, thereby obtaining the polymers (polymer dispersants) of Examples 1 and 10 to 17. Specifically, maleic acid has two carbon atoms connected by a double bond, each of which has one hydrogen atom and one carboxyl group. In the maleic acid used, the hydrogen atom attached to one of the two carbon atoms was replaced with the functional group shown in Table 3. α-Allyl-ω-methoxypoly(oxyethylene) is represented by the following structural formula, with one end being an allyl group (CH2=CH-CH2-) and the other end being a methoxy group (-O-CH3). CH2=CH-CH2(-O-CH2-CH2) n -O-CH3 In the α-allyl-ω-methoxypoly(oxyethylene) used, one hydrogen atom bonded to the second carbon atom from the end of the allyl group (the carbon atom bonded to the terminal CH2 via a double bond) was substituted with a functional group on the allyl group side shown in Table 3. In addition, the methyl group of the methoxy group was substituted with a functional group on the methoxy group side shown in Table 3.

[0118] [Table 3]

[0119] The polymers of Examples 1, 10 to 17 were analyzed using an NMR (nuclear magnetic resonance) analyzer (product name: AVANCE NEO, manufactured by Bruker). 1 H, 13 C-NMR measurement was carried out. Furthermore, the polymers of Examples 1 and 10 to 17 were subjected to pyrolysis GC / MS analysis (gas chromatography mass spectrometry) using a pyrolysis GC / MS analysis device.

[0120] From these results, it can be seen that the polymers of Example 1 and Examples 10 to 17 all have a first terminal group of R 1 -H is a methyl group, and the second terminal group is R 2 -H is the carboxyl group, and the third terminal group is R 3 is a hydrogen atom, and α, β, and n are as shown in Table 2, and it was confirmed that the polymer was a comb polymer represented by formula (I).

[0121] Furthermore, the number average molecular weights (Mn) of the polymers of Examples 1 and 10 to 17 were determined by gel permeation chromatography (GPC). The results are shown in Table 2.

[0122] (Method of producing polymer dispersants of Examples 2 to 5) The polymers (polymer dispersants) of Examples 2 to 5 were obtained in the same manner as in Example 1, except that the molar ratio of maleic acid, which is the raw material for the comb polymer represented by formula (I), to α-allyl-ω-methoxypoly(oxyethylene) was changed.

[0123] The polymers of Examples 2 to 5 were analyzed in the same manner as the polymer of Example 1. As a result, it was found that the first terminal group of each of the polymers of Examples 2 to 5 was R 1 -H and the second terminal group is R 2 -H and R 1 -H, R 2 -H, and the third terminal group, R 3 are shown in Table 2, respectively, and α, β, and n are shown in Table 2, and it was confirmed that the polymer was a comb polymer represented by formula (I). Furthermore, the number average molecular weight (Mn) of each of the polymers of Examples 2 to 5 was determined in the same manner as for the polymer of Example 1. The results are shown in Table 2.

[0124] (Method of producing polymer dispersants of Examples 6 to 9) The polymers (polymer dispersants) of Examples 6 to 9 were obtained in the same manner as in Example 1, except that maleic acid having the substituents shown in Table 3 and α-allyl-ω-methoxypoly(oxyethylene) having the substituents shown in Table 3 were used.

[0125] The polymers of Examples 6 to 9 were analyzed in the same manner as the polymer of Example 1. As a result, it was found that the first terminal group of each of the polymers of Examples 6 to 9 was R 1 -H and the second terminal group is R 2 -H and R 1 -H, R 2 -H, and the third terminal group, R 3 are shown in Table 2, respectively, and α, β, and n are shown in Table 2, and it was confirmed that the polymer was a comb polymer represented by formula (I). Furthermore, the number average molecular weight (Mn) of each of the polymers of Examples 6 to 9 was determined in the same manner as for the polymer of Example 1. The results are shown in Table 2.

[0126] (Comparative Example 1) A black dispersion liquid of Comparative Example 1 was produced in the same manner as in Example 1, except that a compound in which amine groups were bonded to both ends of a main chain made of polyalkyleneimine was used as the polymer dispersant. (Comparative Example 2) A black dispersion liquid of Comparative Example 2 was produced in the same manner as in Example 1, except that no polymer dispersant was contained.

[0127] The Hansen solubility parameters (HSP values) of the surfaces of the black particles contained in the black dispersions were calculated by the method described below for the black dispersions of Examples 1 to 17 and Comparative Examples 1 and 2 obtained in this manner. The results are shown in Table 2.

[0128] [How to calculate Hansen Solubility Parameter (HSP value)] The Hansen solubility parameter (HSP value) of the surface of the black particles contained in the black dispersion was determined by the following method.

[0129] First, the following solvents with known solubility parameters were prepared as solvents for evaluation. Determination solvents: n-pentane, n-hexane, diethyl ether, cyclohexane, ethyl acetate, methyl isobutyl ketone, butyl acetate, methyl propyl ketone, ethylbenzene, xylene, toluene, ethyl acetate, tetrahydrofuran, methyl ethyl ketone, chloroform, methylene chloride, acetone, acetic acid, pyridine, n-hexanol, n-butanol, isopropyl alcohol, N,N-dimethylformamide, ethanol, methanol, ethylene glycol, glycerol carbonate, formamide, water, aniline, acetonitrile, nitrobenzene, methyl cellosolve.

[0130] Next, the black dispersion and each solvent (solvent for evaluation) were mixed so that the ratio of the black pigment in the black dispersion to each solvent (solvent for evaluation) was 5:95 by mass ratio (black pigment:solvent) to obtain a dispersion. The obtained dispersion was allowed to stand at 25°C for 24 hours. The degree of aggregation and precipitation in the dispersion after standing for 24 hours was evaluated by visual observation. The evaluation solvent used for the dispersion in which aggregation and precipitation occurred was determined to be a poor solvent, and the evaluation solvent used for the dispersion in which the dispersed state was maintained was determined to be a good solvent.

[0131] Next, based on the good / poor solvent determination results, the Hansen solubility parameters (HSP values) of the black particle surfaces for each black dispersion were calculated using HSPiP (software "Hansen Solubility Parameters in Practice (HSPiP) ver. 4.1.07") by fitting so that the dissolving spheres contained the most good solvent group. Specifically, the dispersion term (δD), polarity term (δP), and hydrogen bonding term (δH) were calculated using HSPiP, and the representative value δ of the HSP values ​​was calculated using the following formula using the obtained results, which was used as the Hansen solubility parameter (HSP value) of the black particle surfaces. The results are shown in Table 2. Representative value of HSP value δ = (δD 2 +δP 2 +δH 2 ) 1 / 2

[0132] Furthermore, the storage stability of the black dispersions of Examples 1 to 17 and Comparative Examples 1 and 2 was evaluated by the method shown below. [Evaluation of storage stability] The black dispersion was subjected to spectral measurement and viscosity measurement using the methods described below. The black dispersion was then placed in a storage container and stirred for 30 minutes with the opening of the storage container open in an environment at a temperature of 30°C and a humidity of 85%. The opening of the storage container was then sealed, and the black dispersion was stored in the storage container for 24 hours in an environment at a temperature of 30°C and a humidity of 85%. The spectral measurement and viscosity of the black dispersion after storage were performed in the same manner as before storage. The changes in the black dispersion before and after storage were evaluated according to the following criteria, and the results are shown in Table 2.

[0133] (Spectral measurement method) The black dispersion was diluted with propylene glycol monomethyl ether acetate (PGMEA) to a black pigment concentration of 50 ppm by mass. The resulting diluted solution was filled into a cell with an optical path length of 1 cm, and the transmittance was continuously measured in 1 nm increments over the wavelength range of 300 nm to 1000 nm using a spectrophotometer (UH4150, manufactured by Hitachi High-Tech Science Corporation). The transmittance of the black dispersion at each wavelength was obtained by subtracting the transmittance of the cell filled with PGMEA, which had been measured in advance, as a background (baseline) from the transmittance results obtained by the measurement.

[0134] Then, the optical density OD shown in formula (2) was calculated at a wavelength of 365 nm that affects UV curing and a wavelength of 550 nm that affects light blocking properties. Optical density OD(λ)=-log 10 [T(λ) / 100] (2) (T in equation (2) is the transmittance.) The higher the optical density OD value shown by formula (2), the better the light-blocking ability.

[0135] In addition, the OD value ratio shown in formula (3) was calculated from the optical density OD at a wavelength of 365 nm calculated by formula (2) and the optical density OD at a wavelength of 550 nm. OD value ratio = optical density OD at wavelength 365 nm / optical density OD at wavelength 550 nm (3) The lower the OD value ratio shown in formula (3), the higher the transmittance of ultraviolet light and the higher the blocking ability of visible light.

[0136] (Viscosity measurement method) 16 mL of the black dispersion was sampled, and the viscosity was measured using a B-type viscometer (trade name: DV-1, manufactured by Eiko Seiki Co., Ltd.).

[0137] (standard) The OD value ratio calculated from the results of the spectral measurement of the black dispersion liquid and expressed by formula (3) was evaluated as follows based on the increase in the numerical value of the black dispersion liquid after storage relative to the numerical value of the black dispersion liquid before storage (hereinafter referred to as the "spectral increase amount"), and the increase in the numerical value of the black dispersion liquid after storage relative to the numerical value of the black dispersion liquid before storage (hereinafter referred to as the "viscosity increase amount"): Spectral increase = (OD value ratio of black dispersion after storage) - (OD value ratio of black dispersion before storage) Viscosity increase amount = (viscosity of black dispersion after storage) - (viscosity of black dispersion before storage)

[0138] 〇 (good): Meets conditions 1 and 2 below. Condition 1: The amount of spectral increase is 0.1 or less. Condition 2: The increase in viscosity is 10 mPa·s or less.

[0139] △ (fair): Meets any of the following conditions 3 to 5. Condition 3: The increase in the optical spectrum is 0.1 or less, and the increase in viscosity is more than 10 mPa·s and 20 mPa·s or less. Condition 4: The increase in the optical spectrum is more than 0.1 and not more than 0.2, and the increase in viscosity is not more than 10 mPa·s. Condition 5: The increase in the optical spectrum is more than 0.1 and not more than 0.2, and the increase in viscosity is more than 10 mPa·s and not more than 20 mPa·s.

[0140] × (poor): Satisfies condition 6 and / or condition 7 below. Condition 6: The amount of spectral increase is greater than 0.2. Condition 7: The increase in viscosity exceeds 20 mPa·s.

[0141] As shown in Table 2, the surfaces of the black particles contained in the black dispersions of Examples 1 to 17 all had HSP values ​​in the range of 20 to 30, and the hydrophilicity of the black particle surfaces was good. Therefore, the storage stability of the black dispersions of Examples 1 to 17 was evaluated as "Good" or "Good," and it was confirmed that the storage stability was good compared to Comparative Examples 1 and 2.

[0142] More specifically, the HSP value of the black particle surfaces contained in the black dispersion of Comparative Example 1 was 19.8, which was smaller than the HSP value of the black particle surfaces contained in the black dispersions of Examples 1 to 17. Furthermore, the storage stability of the black dispersion of Comparative Example 1 was evaluated as ×. The reason for this is presumably because the black particle surfaces of the black dispersion of Comparative Example 1 were less hydrophilic than the black dispersions of Examples 1 to 17, which used the comb polymer represented by Formula (I) as a polymer dispersant. As a result, it is presumed that the black dispersion of Comparative Example 1 absorbed moisture during storage, causing changes in the physical properties and viscosity of the black dispersion. Furthermore, the black dispersion liquid of Comparative Example 2 did not contain a polymer dispersant, and therefore the black pigment aggregated, resulting in an evaluation of storage stability of "poor."

[0143] [Production of UV-curable black composition] 52.7 parts by mass of any black dispersion liquid selected from Examples 1 to 17, Comparative Examples 1 and 2, 46.9 parts by mass of an ultraviolet-curable organic substance shown below, and 0.4 parts by mass of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide as a photopolymerization initiator were mixed and stirred using a stirrer tip, thereby obtaining 100 parts by mass of an ultraviolet-curable black composition of Examples 1 to 17, Comparative Examples 1 and 2.

[0144] The UV-curable organic material used was a mixture of 2.7 parts by mass of dipentaerythritol hexaacrylate, a monomer having an ethylenically unsaturated bond, and 46.8 parts by mass of Cyclomer P ((ACA)Z250; manufactured by Daicel-Allnex Corporation, active ingredient 52.8% by mass), a monomer or oligomer having a (meth)acryloyl group and a carboxyl group, diluted with 50.5 parts by mass of propylene glycol monomethyl ether acetate (PGMEA) to make 100 parts by mass.

[0145] [Production of black cured film] A glass substrate was prepared in the form of a square plate made of glass with a side length of 100 mm in plan view. Each of the ultraviolet-curable black compositions of Examples 1 to 17 and Comparative Examples 1 and 2 was applied to the entire upper surface of the glass substrate, i.e., the surface to be coated, by spin coating at a rotation speed of 1000 rpm for 60 seconds to form a coating film. The coating film was then dried by heating at a temperature of 100°C for 5 minutes. The coating film was then irradiated with ultraviolet light at a wavelength of 365 nm at an illuminance of 30 mW / cm. 2 The ultraviolet-curable organic material contained in the ultraviolet-curable black composition was cured, and black cured films of Examples 1 to 17 and Comparative Examples 1 and 2 were obtained.

[0146] The black cured films thus obtained in Examples 1 to 17 and Comparative Examples 1 and 2 were evaluated for solvent resistance by the method described below. [Evaluation of solvent resistance] The black cured film formed on the glass substrate was immersed in a solvent, propylene glycol monomethyl ether acetate (PGMEA), for 10 minutes, and then dried at 100°C for 5 minutes. Thereafter, the surface of the black cured film was observed using an optical microscope (trade name: Digital Microscope DSX510; manufactured by Olympus Corporation) and evaluated according to the following criteria. The results are shown in Table 4.

[0147] (standard) ◯ (good): No dissolution was observed on the surface of the black cured film. Δ (fair): Dissolved areas were present on the surface, and the proportion of the dissolved areas to the surface area of ​​the black cured film was less than 10%. × (poor): The proportion of dissolved areas in the surface area of ​​the black cured film is 10% or more.

[0148] [Table 4]

[0149] As shown in Table 4, the solvent resistance of the black cured films of Comparative Examples 1 and 2 was evaluated as "X." This is presumably because the curing of the monomer or oligomer having a (meth)acryloyl group and a carboxyl group, which was contained in the ultraviolet-curable black compositions of Comparative Examples 1 and 2, was inhibited by the elution of basic components derived from zirconium nitride and the polymer dispersant, resulting in the presence of insufficiently cured portions in the black cured film.

[0150] In contrast, the black cured films of Examples 1 to 17 were all evaluated as having excellent solvent resistance, with a rating of "Good" or "Good," demonstrating their excellent durability. This is presumably due to the comb polymer represented by formula (I) contained in the ultraviolet-curable black compositions of Examples 1 to 17 reducing the elution of basic components derived from zirconium nitride. [Industrial Applicability]

[0151] The ultraviolet-curable black composition containing the black dispersion of this embodiment can be used, for example, as a material for forming black patterns such as black matrices for color filters, which are examples of partition wall materials, and black picture frames. Furthermore, the black cured film of this embodiment, which is a cured product of the ultraviolet-curable black composition of this embodiment, can be used as a black matrix used in display devices such as liquid crystal displays, organic EL displays, and touch panels, and as a light-shielding material in solid-state imaging devices such as CMOS image sensors. Furthermore, the black cured film of this embodiment can also be used as a material for light-shielding materials for optical components, light-shielding filters, coverlay films, and the like.

Claims

1. A paint containing a solvent, a black pigment, and a polymer dispersant, The black pigment comprises zirconium nitride, the polymeric dispersant comprises a comb polymer having a backbone, a first end group attached to a first end of the backbone, and a second end group attached to a second end of the backbone opposite the first end; the main chain has a first repeating unit having a structure derived from maleic acid or a structure derived from a condensate of maleic acid, and a second repeating unit having a group containing a polyethylene oxide structure, The black dispersion, wherein the first terminal group and the second terminal group are each selected from a carboxyl group and an alkyl group.

2. 2. The black dispersion according to claim 1, wherein the comb polymer is a polymer represented by the following general formula (I): 【Chemistry 1】 (In general formula (I), the first terminal group and the second terminal group are each selected from a carboxyl group and an alkyl group. R １ -H and R ２ -H is either a carboxyl group or an alkyl group. ３ is any one selected from a carboxyl group, an alkyl group, and a hydrogen atom. α, β, and n represent the number of repeating units, with α being 5 to 20, β being 5 to 75, and n being 2 to 60. The repeating unit having the number of repeating units α is the first repeating unit, and the repeating unit having the number of repeating units β is the second repeating unit.

3. An ultraviolet-curable black composition comprising the black dispersion liquid according to claim 1 or 2, an ultraviolet-curable organic substance, and a photopolymerization initiator.

4. The ultraviolet-curable black composition according to claim 3 , wherein the ultraviolet-curable organic material contains a monomer or oligomer having an ethylenically unsaturated bond.

5. The ultraviolet-curable black composition according to claim 3 , wherein the ultraviolet-curable organic material contains a monomer or oligomer having a (meth)acryloyl group and a carboxyl group.

6. A black cured film which is a cured product of the ultraviolet-curable black composition according to claim 3.

7. A black matrix for a color filter, comprising the black cured film according to claim 6.

8. A color filter comprising the black matrix for a color filter according to claim 7.

9. A partition wall material comprising the black cured film according to claim 6.

10. A display device comprising the partition material according to claim 9 .

11. A light-shielding film for a solid-state imaging device, comprising the black cured film according to claim 6 .

12. A solid-state imaging device comprising the light-shielding film for a solid-state imaging device according to claim 11.

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