Photosensitive resin composition and its cured film, and a color filter having the cured film.

Abstract

To provide a photosensitive resin composition and its cured film which can reduce reflectance with a simple method and can achieve both high light-shielding property and high precision pattern formation, and a color filter having the cured film.SOLUTION: A photosensitive resin composition contains a polymerizable unsaturated group-containing alkali-soluble resin (i) that is obtained by reacting a dicarboxylic acid or a tricarboxylic acid or an acid monoanhydride thereof, and a tetracarboxylic acid or an acid dianhydride thereof with respect to a reactant of an epoxy compound having two or more phenyl glycidyl ether groups in a molecule and an unsaturated group-containing monocarboxylic acid, and has a weight average molecular weight of 2,500 or more, a (meth)acrylate resin (ii) that has a carboxy group and a polymerizable unsaturated group in a side chain and has a weight average molecular weight of 6,000 or more, as resin components, and a light-shielding material (iii) selected from the group consisting of a black organic pigment, a black inorganic pigment and a mixed color organic pigment, as an essential component.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a photosensitive resin composition and its cured film, and a color filter having the cured film. [Background technology]

[0002] Generally, flat panel displays such as liquid crystal displays (LCDs) are equipped with an anti-reflective layer to reduce the reflection of light incident from the outside. Anti-reflective layers mainly consist of Anti-Glare (AG) films and Anti-Reflection (AR) films. AG films prevent reflections by creating irregularities on the surface of the hard coat resin layer to scatter reflected light, and by utilizing internal scattering due to the difference in refractive index between the hard coat resin and the particles. However, this can lead to a decrease in contrast due to the scattering of reflected light on the surface and a decrease in resolution due to internal scattering of transmitted light from the backlight. On the other hand, AR films mainly reduce reflected light by alternately laminating two types of layers with different refractive indices and utilizing the interference of light. Recently, there is also a moth-eye method that creates fine irregularities on the surface of AR films using nanoimprinting, where the refractive index changes continuously. AR films can suppress the decrease in contrast due to scattered light on the surface and the decrease in resolution due to internal scattering, and are the mainstream anti-reflective layer.

[0003] Furthermore, in recent years, the miniaturization and increased resolution of displays have led to a demand for higher contrast and higher definition, requiring reduced reflectivity and improved surface smoothness in anti-reflective layers. In particular, for portable information terminals, digital signage, and in-vehicle displays intended for outdoor use, visibility is greatly affected, and the required characteristics of anti-reflective layers are high. While improvements to anti-reflective layers have greatly improved the visibility of displays, there is also a demand for reduced reflectivity in other components besides the anti-reflective layer.

[0004] Other components besides the anti-reflective layer include, for example, the color filters used in liquid crystal displays. Color filters include colorants that make up the pixels, a black matrix that partitions the pixels, and a protective film that protects the pixels. In particular, the colorants used in the black matrix often have a high refractive index, which has a significant impact on the reflectivity of the color filter. One way to reduce the reflectivity of the black matrix is ​​to reduce the amount of colorant, but this tends to reduce the contrast of the image because it leads to a decrease in light-blocking ability.

[0005] Furthermore, organic electroluminescent displays, which do not use color filters, have been launched, and in recent years, development of displays using micro-LEDs and quantum dots as pixels has also progressed. These self-emissive displays generally do not use color filters, but visibility tends to decrease if the reflectivity of the partitions separating the pixels is high.

[0006] Patent documents 1, 2, and 3 disclose a black matrix in which two layers with different optical densities (a layer with high light-shielding properties on top of a layer with low light-shielding properties) are stacked.

[0007] Patent document 4 discloses a colored cured film in which the reflectance on the side opposite to the substrate (reflectance on the surface side of the colored cured film) is low. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2014-157179 [Patent Document 2] Japanese Patent Publication No. 2014-130368 [Patent Document 3] International Publication No. 2014 / 136738 [Patent Document 4] Japanese Patent Publication No. 2018-141849 [Overview of the project] [Problems that the invention aims to solve]

[0009] According to the inventors' findings, the methods disclosed in Patent Documents 1, 2, and 3 are expected to improve visibility because the refractive index of the black matrix is ​​low with respect to light entering from the substrate side on which the color filter is formed. However, the manufacturing process of the color filter becomes complicated because a layer with high light-shielding properties is laminated after a layer with low light-shielding properties is formed on the substrate, which may reduce productivity.

[0010] Furthermore, in the colored cured film disclosed in Patent Document 4, silica particles are present on the surface of the colored cured film, which sometimes resulted in unevenness on the surface. As a result, while specular reflection is reduced by the surface unevenness, diffuse reflection is increased, and this increase in diffuse reflection may lead to whitening or dullness, potentially resulting in a decrease in texture.

[0011] The present invention has been made in view of the above, and aims to provide a photosensitive resin composition and its cured film, and a color filter having the cured film, which can reduce reflectivity by a simple method and can achieve both high light shielding and high-definition pattern formation. [Means for solving the problem]

[0012] As a result of diligent research to solve the above problems, the present inventors have discovered a photosensitive resin composition that can reduce reflectivity in a simple manner by using two types of resins having specific structures, and that can achieve both high light shielding and high-definition pattern formation.

[0013] That is, the photosensitive resin composition of the present invention is obtained by reacting a dicarboxylic acid, a tricarboxylic acid or their acid anhydrides, and a tetracarboxylic acid or its acid dianhydride with a reaction product of an epoxy compound having two or more phenyl glycidyl ether groups in the molecule and an unsaturated group-containing monocarboxylic acid, and has a weight-average molecular weight of 2500 or more and a polymerizable unsaturated group-containing alkali-soluble resin (i), and a (meth)acrylate resin (ii) having a weight-average molecular weight of 6000 or more and having a carboxy group and a polymerizable unsaturated group in the side chain as resin components, and contains a light-shielding material (iii) selected from the group consisting of a black organic pigment, a black inorganic pigment or a mixed-color organic pigment as an essential component.

[0014] Further, the cured film of the present invention is obtained by curing the above photosensitive resin composition.

[0015] Further, the color filter of the present invention has the above cured film as a black matrix.

Effects of the Invention

[0016] According to the present invention, it is possible to provide a photosensitive resin composition, a cured film thereof, and a color filter having the cured film, which can reduce the reflectance by a simple method and can achieve both high light-shielding properties and high-definition pattern formation.

Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. In the present invention, when the content of each component has a first decimal place of 0, the notation after the decimal point may be omitted.

[0018] A photosensitive resin composition according to one embodiment of the present invention comprises, as a resin component, a polymerizable unsaturated group-containing alkali-soluble resin (i) having a weight-average molecular weight of 2500 or more, obtained by reacting a reaction product of an epoxy compound having two or more phenylglycidyl ether groups in its molecule with an unsaturated group-containing monocarboxylic acid with a dicarboxylic acid or tricarboxylic acid or their acid monoanhydride, and a tetracarboxylic acid or its acid dianhydride; and a (meth)acrylate resin (ii) having a weight-average molecular weight of 6000 or more, with a carboxyl group and a polymerizable unsaturated group in its side chain, and as an essential component, a light-shielding material (iii) selected from the group consisting of black organic pigments, black inorganic pigments, or mixed organic pigments.

[0019] The following explains components (i) to (iii).

[0020] (Alkali-soluble resin containing polymerizable unsaturated groups) A polymerizable unsaturated group-containing alkali-soluble resin having a weight-average molecular weight of 2500 or more, which is component (i) according to one embodiment of the present invention, is represented by the following general formula (1).

[0021] [ka]

[0022] (In formula (1), R1 is independently a hydrocarbon group having 2 to 4 carbon atoms, R2 is independently a hydrocarbon group having 1 to 3 carbon atoms, R3 is independently a hydrogen atom or a methyl group, X is independently a divalent organic group having 1 to 20 carbon atoms which may contain heteroatoms, -CO-, -SO2-, -C(CF3)2-, -CH2-, -C(CH3)2-, -Si(CH3)2-, -O-, a fluorene-9,9-diyl group represented by general formula (2), or a single bond, Y is a tetravalent carboxylic acid residue, and Z is independently Z is a hydrogen atom or a substituent represented by general formula (3). However, at least one of Z is a substituent represented by general formula (3), G is independently a hydrogen atom or a substituent represented by general formula (4), a is independently a number between 0 and 10, the average value of a in one molecule is also between 0 and 10, and the average value of a in the composition is also between 0 and 10. b is independently a number between 0 and 4, the average value of b in one molecule is also between 0 and 4, and the average value of b in the composition is also between 0 and 4. n is an integer with an average value between 1 and 20.

[0023] [ka]

[0024] [ka]

[0025] [ka]

[0026] (In formulas (3) and (4), R4 and R6 are hydrogen atoms or methyl groups, R5 and R7 are hydrocarbon groups having 2 to 4 carbon atoms, L is a divalent or trivalent carboxylic acid residue, c and f are numbers of 0 or 1, d and e are numbers of 0, 1 or 2, and d+e is a number of 1 or 2.)

[0027] A method for producing an alkali-soluble resin (i) containing polymerizable unsaturated groups with a weight-average molecular weight of 2500 or more, represented by the above general formula (1) (hereinafter also simply referred to as "alkali-soluble resin represented by general formula (1)") will be described below.

[0028] First, a bisphenol-type epoxy compound (a-1) having two or more phenylglycidyl ether groups in one molecule, represented by the general formula (8) below (hereinafter also simply referred to as "epoxy compound represented by general formula (8)") is reacted with an unsaturated group-containing monocarboxylic acid (e.g., (meth)acrylic acid) to obtain a diol containing a polymerizable unsaturated group. Note that "(meth)acrylic acid" is a general term for acrylic acid and methacrylic acid, and means one or both of these.

[0029] [ka]

[0030] (In formula (8), R1 is independently a hydrocarbon group having 2 to 4 carbon atoms, R2 is independently a hydrocarbon group having 1 to 3 carbon atoms, X is independently a divalent organic group having 1 to 20 carbon atoms which may contain heteroatoms, -CO-, -SO2-, -C(CF3)2-, -CH2-, -C(CH3)2-, -Si(CH3)2-, -O-, a fluorene-9,9-diyl group represented by general formula (2), or a single bond, a is independently a number from 0 to 10, and b is independently a number from 0 to 4.)

[0031] [ka]

[0032] The epoxy compounds represented by general formula (8) are epoxy compounds obtained by reacting bisphenols with epichlorohydrin, and each molecule contains two phenylglycidyl ether groups. This reaction generally involves oligomerization of the diglycidyl ether compound, and therefore contains epoxy compounds with two or more bisphenol skeletons.

[0033] Examples of the bisphenols listed above include bis(4-hydroxyphenyl)ketone, bis(4-hydroxy-3,5-dimethylphenyl)ketone, bis(4-hydroxy-3,5-dichlorophenyl)ketone, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxy-3,5-dimethylphenyl)sulfone, bis(4-hydroxy-3,5-dichlorophenyl)sulfone, bis(4-hydroxyphenyl)hexafluoropropane, bis(4-hydroxy-3 ,5-dichlorophenyl)hexafluoropropane, bis(4-hydroxyphenyl)dimethylsilane, bis(4-hydroxy-3,5-dimethylphenyl)dimethylsilane, bis(4-hydroxy-3,5-dichlorophenyl)dimethylsilane, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3,5-dichlorophenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, bis(4-hydroxyphenyl) ether, bis(4-hydroxy-3,5-dimethylphenyl) ether, bis(4-hydroxy-3,5-dichlorophenyl) ether, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3)fluorene, 9,9-bis(4-hydroxy-3 This includes 9,9-chlorophenyl fluorene, 9,9-bis(4-hydroxy-3-bromophenyl)fluorene, 9,9-bis(4-hydroxy-3-fluorophenyl)fluorene, 9,9-bis(4-hydroxy-3-methoxyphenyl)fluorene, 9,9-bis(4-hydroxy-3,5-dimethylphenyl)fluorene, 9,9-bis(4-hydroxy-3,5-dichlorophenyl)fluorene, 9,9-bis(4-hydroxy-3,5-dibromophenyl)fluorene, 4,4'-biphenol, 3,3'-biphenol, and others.

[0034] Examples of unsaturated monocarboxylic acids that react with epoxy compounds represented by general formula (8) include, in addition to acrylic acid and methacrylic acid, compounds obtained by reacting acrylic acid or methacrylic acid with acid monoanhydrides such as succinic anhydride, maleic anhydride, and phthalic anhydride.

[0035] The reaction between the epoxy compound represented by general formula (8) and the above-mentioned monocarboxylic acid containing an unsaturated group can be carried out using known methods. For example, Japanese Patent Publication No. 4-355450 describes that a diol containing a polymerizable unsaturated group can be obtained by using about 2 moles of (meth)acrylic acid per 1 mole of epoxy compound having two epoxy groups. In the present invention, the reactant obtained in the above reaction is a diol (d) containing a polymerizable unsaturated group represented by general formula (9) (hereinafter also simply referred to as "the diol represented by general formula (9)").

[0036] [ka]

[0037] (In formula (9), R1 is independently a hydrocarbon group having 2 to 4 carbon atoms, R2 is independently a hydrocarbon group having 1 to 3 carbon atoms, R3 is independently a hydrogen atom or a methyl group, X is independently a divalent organic group having 1 to 20 carbon atoms which may contain heteroatoms, -CO-, -SO2-, -C(CF3)2-, -CH2-, -C(CH3)2-, -Si(CH3)2-, -O-, a fluorene-9,9-diyl group represented by general formula (2), or a single bond, a is independently a number from 0 to 10, and b is independently a number from 0 to 4.)

[0038] [ka]

[0039] Examples of divalent organic groups having 1 to 20 carbon atoms include divalent hydrocarbon groups and divalent groups having one or two carboxyl groups in the side chain of the hydrocarbon group. Note that the hydrocarbon groups may contain an ether-bonded oxygen atom or an ester bond internally.

[0040] Furthermore, examples of the above-mentioned divalent hydrocarbon groups include linear or branched hydrocarbon groups such as methylene, ethylene, propylene, isopropylidene, sec-butylene, methylisobutylene, hexylene, decylene, and dodecylene. Additionally, examples of divalent groups having an ester bond inside the hydrocarbon group include divalent organic groups represented by general formulas (10) to (12).

[0041] [ka]

[0042] (In equation (10), h is an integer between 1 and 20.)

[0043] [ka]

[0044] (In equation (11), i is an integer between 2 and 20, and j is an integer between 0 and 10.)

[0045] [ka]

[0046] (In equation (12), k is an integer between 0 and 18, and l is an independent integer between 1 and 10.)

[0047] Furthermore, examples of dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides that react with the hydroxyl group in the molecule of a diol represented by general formula (9), which is a reaction product of an epoxy compound represented by general formula (8) and an unsaturated monocarboxylic acid, include chain-type hydrocarbon dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides, alicyclic hydrocarbon dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides, aromatic dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides, etc.

[0048] Examples of the above-mentioned chain-like hydrocarbon dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides include succinic acid, acetylsuccinic acid, maleic acid, adipic acid, itaconic acid, azelaic acid, citramalic acid, malonic acid, glutaric acid, citric acid, tartaric acid, oxoglutaric acid, pimelic acid, sebacic acid, suberic acid, diglycolic acid, and their acid monoanhydrides. Furthermore, dicarboxylic acids or tricarboxylic acids to which any of these substituents have been introduced, and their acid monoanhydrides, etc., are also included.

[0049] Examples of the above-mentioned alicyclic hydrocarbon dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides include acid monoanhydrides such as cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, norbornanedicarboxylic acid, methyltetrahydrophthalic acid, methyl-3,6-endomethylenetetrahydrophthalic acid, chlorendic acid, and hexahydrotrimellitic acid. Furthermore, dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides to which any of these substituents have been introduced are also included.

[0050] Examples of the above aromatic dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides include phthalic acid, isophthalic acid, trimellitic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid and their acid monoanhydrides. Furthermore, dicarboxylic acids or tricarboxylic acids and their acid monoanhydrides to which any of these substituents have been introduced are also included.

[0051] Among the dicarboxylic acids or tricarboxylic acids or their acid monoanhydrides, succinic acid, itaconic acid, tetrahydrophthalic acid, hexahydrotrimellitic acid, phthalic acid, and trimellitic acid are preferred, and succinic acid, itaconic acid, and tetrahydrophthalic acid are more preferred. Furthermore, among the dicarboxylic acids or tricarboxylic acids, it is preferable to use their acid monoanhydrides. The acid monoanhydrides of the dicarboxylic acids or tricarboxylic acids described above may be used individually or in combination of two or more types.

[0052] Furthermore, examples of (b) tetracarboxylic acids or their acid dianhydrides that react with the hydroxyl group in the molecule of a diol represented by general formula (9), which is a reaction product of an epoxy compound represented by general formula (8) and an unsaturated monocarboxylic acid, include chain-type hydrocarbon tetracarboxylic acids, alicyclic hydrocarbon tetracarboxylic acids, aromatic tetracarboxylic acids, or their acid dianhydrides.

[0053] Examples of the above-mentioned chain-type hydrocarbon tetracarboxylic acids include butanetetracarboxylic acid, pentanetetracarboxylic acid, hexanetetracarboxylic acid, and chain-type hydrocarbon tetracarboxylic acids into which substituents such as alicyclic hydrocarbon groups and unsaturated hydrocarbon groups have been introduced.

[0054] Examples of the above-mentioned alicyclic hydrocarbon tetracarboxylic acids include cyclobutanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, cycloheptanetetracarboxylic acid, norbornanetetracarboxylic acid, and alicyclic tetracarboxylic acids into which substituents such as chain hydrocarbon groups and unsaturated hydrocarbon groups have been introduced.

[0055] Examples of aromatic tetracarboxylic acids include pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, diphenyl ethertetracarboxylic acid, diphenyl sulfonetetracarboxylic acid, naphthalene-1,4,5,8-tetracarboxylic acid, and naphthalene-2,3,6,7-tetracarboxylic acid.

[0056] Among the tetracarboxylic acids mentioned above, biphenyltetracarboxylic acid, benzophenonetetracarboxylic acid, and diphenyl ethertetracarboxylic acid are preferred, and biphenyltetracarboxylic acid and diphenyl ethertetracarboxylic acid are more preferred. Furthermore, in the case of tetracarboxylic acids or their acid dianhydrides, it is preferable to use the acid dianhydride. Note that the tetracarboxylic acids or their acid dianhydrides mentioned above may be used individually or in combination of two or more types.

[0057] The molar ratio (a) / (b) of (a) a dicarboxylic acid or tricarboxylic acid or its monoanhydride, and (b) a tetracarboxylic acid or its dianhydride, which react with the hydroxyl group in the molecule of the diol represented by the general formula (9) above, is preferably 0.01 or more and 10.0 or less, and more preferably 0.02 or more and less than 3.0. When the molar ratio (a) / (b) is 0.01 or more and 10.0 or less, the optimal molecular weight for a photosensitive resin composition with good photopatternability can be obtained. Note that the smaller the molar ratio (a) / (b), the larger the molecular weight and the lower the alkali solubility tends to be.

[0058] Furthermore, the reaction between the epoxy compound represented by general formula (8) and an unsaturated group-containing monocarboxylic acid, and the reaction between the diol represented by general formula (9) obtained in the said reaction and a polybasic acid or its acid anhydride, are not particularly limited, and known methods can be employed.

[0059] The weight-average molecular weight (Mw) of the alkali-soluble resin represented by general formula (1) synthesized in the above reaction is 2500 or more, preferably 2500 to 100000, and more preferably 2500 to 25000. The larger the weight-average molecular weight (Mw), the more it separates from the (meth)acrylate resin (described later) and forms a thin layer (10-100 nm) on the outermost surface (the side not in contact with the substrate) of the cured film. This reduces reflectivity without the need to provide an anti-reflective coating or the like on the outermost surface (the side not in contact with the substrate) of the cured film. Furthermore, the smaller the weight-average molecular weight (Mw), the more effectively it is possible to suppress the decrease in pattern adhesion during alkaline development, and the easier it is to adjust the solution viscosity of the photosensitive resin composition to a suitable level for coating, thus preventing excessive time required for alkaline development.

[0060] Furthermore, the acid value of the alkali-soluble resin represented by the above general formula (1) is preferably 30 mg KOH / g or more and 200 mg KOH / g or less, more preferably 40 mg KOH / g or more and 140 mg KOH / g or less, and even more preferably 80 mg KOH / g or more and 120 mg KOH / g or less. When the acid value of the alkali-soluble resin is 30 mg KOH / g or more, residue is less likely to remain during alkaline development. Also, when it is 200 mg KOH / g or less, the penetration of the alkaline developer does not become too fast, so peeling development can be suppressed.

[0061] The weight-average molecular weight (Mw) of an alkali-soluble resin represented by general formula (1) can be measured, for example, by gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation). Furthermore, the acid value of an alkali-soluble resin represented by general formula (1) can be measured, for example, using a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.).

[0062] Furthermore, the alkali-soluble resin represented by general formula (1) of component (i) may be used alone or in combination of two or more types.

[0063] The mass of the alkali-soluble resin represented by general formula (1) is preferably 40 to 99% by mass, more preferably 40 to 90% by mass, even more preferably 40 to 80% by mass, even more preferably 50 to 80% by mass, and particularly preferably 65 to 80% by mass, based on the total mass of the alkali-soluble resin represented by general formula (1) and the (meth)acrylate resin represented by general formula (13) (described later). When the mass of the alkali-soluble resin is 40 to 99% by mass, the reflectance can be reduced while maintaining high-definition pattern formation.

[0064] ((meth)acrylate resin) A (meth)acrylate resin having a weight-average molecular weight of 6000 or more and having a carboxyl group and a polymerizable unsaturated group in its side chain, which is component (ii) according to one embodiment of the present invention, is represented, for example, by the following general formula (13). General formula (13) is a random copolymer containing m, o, and p units, respectively.

[0065] [ka]

[0066] (In formula (13), R8, R 10 , R 11 R is independently a hydrogen atom or a methyl group, R9 is a hydrocarbon group having 1 to 20 carbon atoms, and R9 may contain an etheric oxygen atom or a urethane bond internally. 12 (where is independently a divalent hydrocarbon group having 2 to 10 carbon atoms, g is independently a number 0 or 1, and m, o, and p are independently any integers.)

[0067] A method for producing a (meth)acrylate resin (ii) (hereinafter also simply referred to as "(meth)acrylate resin represented by general formula (13)") having a weight-average molecular weight of 6000 or more and having a carboxyl group and a polymerizable unsaturated group in the side chain represented by the above general formula (13) will be described below.

[0068] A (meth)acrylate resin represented by general formula (13) according to one embodiment of the present invention is derived from a polycarboxylic acid compound represented by the following general formula (14), obtained by copolymerizing (meth)acrylate represented by general formula (5) and (meth)acrylic acid represented by general formula (6). General formula (14) is a random copolymer containing m and o units, respectively.

[0069] [ka]

[0070] (In formula (5), R8 is a hydrogen atom or a methyl group, and R9 is a hydrocarbon group having 1 to 20 carbon atoms, and R9 may contain an etheric oxygen atom or a urethane bond internally.)

[0071] [ka]

[0072] (In formula (6), R 10 (This is either a hydrogen atom or a methyl group.)

[0073] [ka]

[0074] (In formula (14), R8, R 10 (where is a hydrogen atom or a methyl group, R9 is a hydrocarbon group having 1 to 20 carbon atoms, and R9 may contain an etheric oxygen atom or a urethane bond internally. o and m are any integers.)

[0075] Examples of the hydrocarbon group R9 represented by the above general formula (5) include linear hydrocarbon groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, isooctyl, decyl, dodecyl, tetradecyl, and eicosyl groups; cyclic aliphatic hydrocarbon groups such as cyclohexyl, norbornyl, isobornyl, tricyclodecylmethyl, decahydronaphthyl, and substituents represented by the following general formula (15); aliphatic ethers such as methoxyethyl and 2-(methoxyethoxy)ethyl groups; and aliphatic urethanes such as 2-(ethoxycarbonylamino)ethyl groups.

[0076] [ka]

[0077] (In formula (15), R 13 (This is either a hydrogen atom or a methyl group.)

[0078] Among the hydrocarbon groups listed above, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, cyclohexyl, norbornyl, isobornyl, and tricyclodecylmethyl groups are preferred, and methyl, ethyl, cyclohexyl, norbornyl, isobornyl, and tricyclodecylmethyl groups are more preferred.

[0079] The (meth)acrylate represented by the general formula (5) above may be used alone or in combination of two or more types. Similarly, the (meth)acrylic acid represented by the general formula (6) may be used alone or in combination of two or more types.

[0080] The polycarboxylic acid represented by the above general formula (14) is a copolymer in which components derived from (meth)acrylate represented by general formula (5) and components derived from (meth)acrylic acid represented by general formula (6) are basically randomly bonded together. The copolymerization method is not particularly limited, and known copolymerization methods can be used.

[0081] In the polycarboxylic acid represented by general formula (14), the repeating units (m) of the constituent component derived from (meth)acrylate represented by general formula (5) and the repeating units (o) of the constituent component derived from (meth)acrylic acid represented by general formula (6) are preferably 20 to 70, and more preferably 30 to 60, when the sum of the number of m and o is 100, considering the reaction with (meth)acrylate having an epoxy group represented by general formula (7). Similarly, the number of o is preferably 30 to 80, and more preferably 40 to 70. Note that m and o are independent of each other and can be any integer. By setting m to 20 to 70 and o to 30 to 80, it is possible to achieve both solubility in alkaline developers and curability.

[0082] Then, by reacting a (meth)acrylate having an epoxy group represented by general formula (7) with a portion of the carboxyl groups of a polycarboxylic acid compound represented by general formula (14), a (meth)acrylate resin represented by general formula (13) according to one embodiment of the present invention is obtained. Note that there is no particular regularity in the bonding order of the above constituent components, and it is basically a copolymer in which the components are bonded randomly.

[0083] [ka]

[0084] (In formula (7), R 11 R is a hydrogen atom or a methyl group, 12 (where g is a divalent hydrocarbon group with 2 to 10 carbon atoms, and g is the number 0 or 1.)

[0085] In general formula (13), there is no particular regularity in the bonding order of the three components: a component derived from the (meth)acrylate compound represented by general formula (5), a component derived from the (meth)acrylic acid compound represented by general formula (6), and a component in which a (meth)acrylate having an epoxy group represented by general formula (7) is attached to some of the carboxyl groups of the component derived from (meth)acrylic acid represented by general formula (6). The copolymer is basically formed by randomly bonding the three components.

[0086] The solvent used when reacting a (meth)acrylate having an epoxy group represented by general formula (7) with some of the carboxyl groups in the polycarboxylic acid represented by general formula (14) above is not particularly limited, but it is preferable that the solvent has a boiling point higher than the reaction temperature.

[0087] Examples of the solvents mentioned above include cellosolve-based solvents such as ethyl cellosolve acetate and butyl cellosolve acetate; high-boiling point ether-based or ester-based solvents such as ethyl carbitol acetate, butyl carbitol acetate, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, and butyl acetate; and ketone-based solvents such as cyclohexanone and diisobutyl ketone.

[0088] Furthermore, the catalyst used is not particularly limited and includes, for example, ammonium salts such as tetraethylammonium bromide and triethylbenzylammonium chloride described in Japanese Patent Publication No. 9-325494, phosphines such as triphenylphosphine and tris(2,6-dimethoxyphenyl)phosphine.

[0089] The reaction temperature when producing a (meth)acrylate resin represented by general formula (13) by reacting a polycarboxylic acid represented by general formula (14) with a (meth)acrylate having an epoxy group represented by general formula (7) is preferably 20 to 140°C, and more preferably 40 to 130°C.

[0090] Furthermore, the charging ratio of the (meth)acrylate having epoxy groups represented by general formula (7) and the polycarboxylic acid represented by general formula (14) when producing the (meth)acrylate resin represented by general formula (13) can be arbitrarily changed for the purpose of adjusting the acid value and curability of the (meth)acrylate resin represented by general formula (13). In this case, the charging ratio of epoxy groups in the (meth)acrylate having epoxy groups represented by general formula (7) to carboxyl groups in the polycarboxylic acid represented by general formula (14) is preferably 10 to 50 mol%, and more preferably 30 to 50 mol%.

[0091] Furthermore, the number of repeating units (m, o, p) in the (meth)acrylate resin represented by general formula (13), when the sum of the repeating units (m, o, p) is set to 100, can be arbitrarily changed for the purpose of adjusting the acid value and curability. The repeating unit (m) is preferably 20 to 70, more preferably 30 to 60; the repeating unit (o) is preferably 5 to 70, more preferably 10 to 50; and the repeating unit (p) is preferably 10 to 75, more preferably 20 to 60. When m is 20 to 70, the content of polymerizable double bonds decreases, which can suppress a decrease in the adhesion and hardness of the cured film. Also, when o is 10 to 50, the water absorption rate of the cured film does not become too high, thus improving solubility in organic solvents. Also, when p is 10 to 40, the volume shrinkage during curing does not become too large, thus improving adhesion to the substrate and surface flatness.

[0092] The weight-average molecular weight (Mw) of the (meth)acrylate resin represented by general formula (13) is 6,000 or more, preferably 6,000 to 1,000,000, and more preferably 10,000 to 1,000,000. The larger the weight-average molecular weight (Mw), the more likely it is to undergo phase separation with the aforementioned alkali-soluble resin, forming a thin layer (10-100 nm) on the outermost surface of the cured film (the side not in contact with the substrate), thus reducing reflectivity without the need to provide an anti-reflective coating or the like on the outermost surface of the cured film (the side not in contact with the substrate). Furthermore, the smaller the weight-average molecular weight (Mw), the more likely it is to suppress a decrease in adhesion, a decrease in curability, and deterioration of appearance due to the phase separation.

[0093] Furthermore, the acid value of the (meth)acrylate resin represented by general formula (13) is preferably 30 mg KOH / g or more and 200 mg KOH / g, and more preferably 40 mg KOH / g or more and 140 mg KOH / g or less. When the acid value of the (meth)acrylate resin is 30 mg KOH / g or more, residue is less likely to remain during alkaline development. Also, when it is 200 mg KOH / g or less, the penetration of the alkaline developer does not become too fast, so peeling development can be suppressed.

[0094] The weight-average molecular weight (Mw) and acid value of the (meth)acrylate resin represented by the above general formula (13) can be measured using the same apparatus as that used for the alkali-soluble resin represented by general formula (1).

[0095] The mass of the (meth)acrylate resin represented by general formula (13) is preferably 1 to 60% by mass, more preferably 10 to 60% by mass, even more preferably 20 to 60% by mass, even more preferably 20 to 50% by mass, and particularly preferably 20 to 35% by mass, relative to the total mass of the alkali-soluble resin represented by general formula (1) and the (meth)acrylate resin represented by general formula (13). Furthermore, when the mass of the (meth)acrylate resin is 1 to 60% by mass, the cross-linking structure is sufficiently formed, so the cured film after curing is less likely to become brittle. From the viewpoint of more effectively obtaining the effect of reducing reflectivity due to phase separation, it is preferable that the mass ratio of the (meth)acrylate resin represented by general formula (13) is higher. Furthermore, from the viewpoint of suppressing the deterioration of surface texture due to the above phase separation, it is preferable that the mass ratio of the (meth)acrylate resin represented by general formula (13) is 50% by mass or less, and more preferably 35% by mass or less.

[0096] (shading material) The light-shielding material, which is component (iii) according to one embodiment of the present invention, is selected from the group consisting of black organic pigments, black inorganic pigments, or mixed organic pigments.

[0097] The light-shielding material that can be used in this invention is not particularly limited to any known light-shielding component, as long as it is dispersed with an average particle size of 1 to 1000 nm. The average particle size of the above light-shielding material can be measured, for example, by a laser diffraction / scattering particle size analyzer or a dynamic light scattering particle size analyzer.

[0098] Examples of the black organic pigments mentioned above include perylene black, cyanine black, aniline black, lactam black, and others.

[0099] Examples of the black inorganic pigments mentioned above include carbon black, chromium oxide, iron oxide, and titanium black.

[0100] Examples of the above mixed organic pigments include mixed pigments that are pseudo-blackened by mixing at least two pigments selected from organic pigments such as azo pigments, condensed azo pigments, azomethine pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, isoindoline pigments, dioxazine pigments, surene pigments, perylene pigments, perinone pigments, quinophthalone pigments, diketopyrrolopyrrole pigments, and thioindigo pigments.

[0101] The above light-shielding materials may be used individually or in combination of two or more, depending on the desired function of the photosensitive resin composition. For example, carbon black, titanium black, black organic pigments, etc. can be used as light-shielding resists used in the manufacture of the black matrix of a color filter; red, orange, yellow, green, blue, purple organic pigments, etc. can be used as coloring resists used in the manufacture of pixels of a color filter; organic pigments, inorganic pigments, inorganic fillers, etc. can be used as solder resists used in the manufacture of insulating films of printed circuit boards; carbon black, titanium black, black organic pigments, white pigments, etc. can be used as decorative resists used in the design of the front glass of a touch panel; and transparent fillers such as silica can be used as transparent resists with high hardness and high durability. Each of these can be selected and used as appropriate.

[0102] (iii) When using a mixed organic pigment as component, examples of organic pigments that can be used include, but are not limited to, those with the following color index numbers. Pigment Red 2, 3, 4, 5, 9, 12, 14, 22, 23, 31, 38, 112, 122, 144, 146, 147, 149, 166, 168, 170, 175, 176, 177, 178, 179, 184, 185, 187, 188, 202, 207, 208, 209, 210, 213, 214, 220, 221, 242, 247, 253, 254, 255, 256, 257, 262, 264, 266, 272, 279, etc. Pigment Orange 5, 13, 16, 34, 36, 38, 43, 61, 62, 64, 67, 68, 71, 72, 73, 74, 81, etc. Pigment Yellow 1, 3, 12, 13, 14, 16, 17, 55, 73, 74, 81, 83, 93, 95, 97, 109, 110, 111, 117, 120, 126, 127, 128, 129, 130, 136, 138, 139, 150, 151, 153, 154, 155, 173, 174, 175, 176, 180, 181, 183, 185, 191, 194, 199, 213, 214, etc. Pigment Green 7, 36, 58, etc. Pigment Blue in 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 60, 80, etc. Pigment Violet 19, 23, 37, etc.

[0103] The amount of the above-mentioned light-shielding material can be arbitrarily determined according to the desired degree of light shielding, but it is preferably 20 to 80% by mass, and more preferably 40 to 70% by mass, relative to the solid components in the photosensitive resin composition.

[0104] When using black organic pigments such as aniline black, cyanine black, or lactam black, or black inorganic pigments such as carbon black or titanium black, as light-shielding materials, it is particularly preferable that the amount is 40 to 60% by mass relative to the solid components in the photosensitive resin composition. If the amount of light-shielding material is 20% by mass or more relative to the solid components in the photosensitive resin composition, sufficient light-shielding properties can be obtained. Furthermore, if the amount of light-shielding material is 80% by mass or less relative to the solid components in the photosensitive resin composition, the amount of the photosensitive resin that acts as the binder will not decrease, and the desired development characteristics and film-forming ability can be obtained.

[0105] The above-mentioned light-shielding material is typically mixed with other components as a light-shielding material dispersion in a solvent, and a dispersant may be added in this process. The dispersant that can be used is not particularly limited, and known compounds used for dispersing pigments (light-shielding materials) (compounds commercially available under names such as dispersants, dispersion wetting agents, dispersion accelerators, etc.) can be used.

[0106] Examples of dispersants include cationic polymer dispersants, anionic polymer dispersants, nonionic polymer dispersants, and pigment derivative type dispersants (dispersion aids). In particular, the dispersant is preferably a cationic polymer dispersant having cationic functional groups such as imidazolyl groups, pyrrolyl groups, pyridyl groups, or primary, secondary, or tertiary amino groups as adsorption sites to the colorant, with an amine value of 1 to 100 mg KOH / g and a number average molecular weight (Mn) in the range of 1,000 to 100,000. The content of this dispersant is preferably 1 to 35% by mass, and more preferably 2 to 25% by mass, relative to the total mass of the light-shielding material. Although high-viscosity substances such as resins generally have the effect of stabilizing dispersion, those that do not have dispersion-promoting ability are not treated as dispersants. However, this does not restrict their use for the purpose of stabilizing dispersion.

[0107] (Photopolymerizable monomer) A photosensitive resin composition according to one embodiment of the present invention preferably contains a photopolymerizable monomer having at least two polymerizable unsaturated groups, which is component (iv).

[0108] Examples of the above photopolymerizable monomers include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tetramethylene glycol di(meth)acrylate, glycerol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, This includes (meth)acrylic acid esters such as dipentaerythritol tetra(meth)acrylate, glycerol tri(meth)acrylate, sorbitol penta(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, alkylene oxide-modified hexa(meth)acrylate of phosphazene, and caprolactone-modified dipentaerythritol hexa(meth)acrylate, as well as dendritic polymers having a (meth)acrylic group as a compound having an ethylenic double bond. One of these monomers may be used alone, or two or more may be used in combination.

[0109] Furthermore, the above-mentioned photopolymerizable monomer can play a role in crosslinking the molecules of the alkali-soluble resin. To exhibit this function, it is preferable that it has at least two ethylenically unsaturated bonds, and more preferably three or more ethylenically unsaturated bonds. In addition, the acrylic equivalent obtained by dividing the molecular weight of the monomer by the number of (meth)acrylic groups in one molecule is preferably 50 to 300 g / eq, and more preferably 80 to 200 g / eq. Note that the above-mentioned photopolymerizable monomer does not have free carboxyl groups.

[0110] In addition, a dendritic polymer having a (meth)acryloyl group can be used as the compound having an ethylenically unsaturated bond. Examples of the dendritic polymer include dendritic polymers obtained by adding a polyvalent mercapto compound to a part of the carbon-carbon double bond in the (meth)acryloyl group of a polyfunctional (meth)acrylate. Specifically, it includes dendritic polymers obtained by reacting a (meth)acryloyl group of a polyfunctional (meth)acrylate represented by the general formula (16) with a polyvalent mercapto compound represented by the general formula (17).

[0111]

Chemical formula

[0112] (In formula (16), R 14 is a hydrogen atom or a methyl group, and R 15 is the remaining part obtained by donating n hydroxy groups out of k hydroxy groups of R 16 (OH) k to the ester bond in the formula. Preferred R 16 (OH) k is a polyhydric alcohol based on a non-aromatic linear or branched hydrocarbon skeleton having 2 to 8 carbon atoms, a polyhydric alcohol ether formed by linking a plurality of molecules of the polyhydric alcohol via an ether bond by dehydration condensation of the alcohol, or an ester of these polyhydric alcohols or polyhydric alcohol ethers and a hydroxy acid.)

[0113]

Chemical formula

[0114] (In formula (17), R 17 is a single bond or a C1-C6 hydrocarbon group having a valence of 2 to 6, and r is 2 when R 17 is a single bond, and is an integer of 2 to 6 when R 17 is a group having a valence of 2 to 6.)

[0115] Furthermore, the q shown in general formula (16) and the r shown in general formula (17) independently represent integers from 2 to 20, but q ≥ r.

[0116] Examples of polyfunctional (meth)acrylates represented by the above general formula (16) include (meth)acrylic acid esters such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and caprolactone-modified pentaerythritol tri(meth)acrylate. These compounds may be used individually or in combination of two or more types.

[0117] Examples of polyvalent mercapto compounds represented by the above general formula (17) include trimethylolpropanetri(mercaptoacetate), trimethylolpropanetri(mercaptopropionate), pentaerythritoltetra(mercaptoacetate), pentaerythritoltri(mercaptoacetate), pentaerythritoltetra(mercaptopropionate), dipentaerythritolhexa(mercaptoacetate), and dipentaerythritolhexa(mercaptopropionate). These compounds may be used individually or in combination of two or more.

[0118] The mixing ratio of component (i) to component (iv) is preferably 50 / 50 to 90 / 10 by weight, and more preferably 60 / 40 to 80 / 20. When the mixing ratio of component (i) is 50 / 50 or higher, the cured product is less likely to become brittle after curing, and the acid value of the coating film in the unexposed areas is less likely to decrease, thus suppressing a decrease in solubility in alkaline developer. Therefore, problems such as jagged or dull pattern edges are less likely to occur. Furthermore, when the mixing ratio of component (i) is 90 / 10 or lower, the proportion of photoreactive functional groups in the resin is sufficient, so the desired cross-linked structure can be formed. In addition, since the acid value of the resin component is not too high, the solubility in alkaline developer in the exposed areas is less likely to increase, thus preventing the formed pattern from becoming thinner than the target line width and suppressing pattern loss.

[0119] (Photopolymerization initiator) A photosensitive resin composition according to one embodiment of the present invention preferably contains a photopolymerization initiator which is component (v).

[0120] Examples of the above photopolymerization initiators include acetophenones such as acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, and p-tert-butylacetophenone; benzophenones such as benzophenone, 2-chlorobenzophenone, and p,p'-bisdimethylaminobenzophenone; and benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether. Nzoin ethers; biimidazole compounds such as 2-(o-chlorophenyl)-4,5-phenylbiimidazole, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)biimidazole, 2-(o-fluorophenyl)-4,5-diphenylbiimidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, 2,4,5-triarylbiimidazole; 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl Halomethylthiazole compounds such as )-1,3,4-oxadiazole and 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4-oxadiazole; 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-phenyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-chlorophenyl)-4,6-bis(trichloromethyl-1,3,5-triazine, 2-(4-methoxyphenyl) Halomethyl-S-triazine compounds such as -4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4,5-trimethoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine;1,2-Octanedione, 1-[4-(phenylthio)phenyl]-,2-(O-benzoyloxime), 1-(4-phenylsulfanylphenyl)butane-1,2-dione-2-oxime-O-benzoate, 1-(4-methylsulfanylphenyl)butane-1,2-dione-2-oxime-O-acetate, 1-(4-methylsulfanylphenyl)butane-1-one oxime-O-acetate, 4-ethoxy-2-methylphenyl-9-ethyl-6-nitro-9H-carbazol-3-yl-O-acetyloxime, ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(O-acetyloxime), etc., O-acyl These include oxime compounds; sulfur compounds such as benzyldimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, and 2-isopropylthioxanthone; anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, and 2,3-diphenylanthraquinone; organic peroxides such as azobisisobutyronitrile, benzoyl peroxide, and cumene peroxide; thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, and 2-mercaptobenzothiazole; and tertiary amines such as triethanolamine and triethylamine. These photopolymerization initiators may be used individually or in combination of two or more types.

[0121] In particular, when a photosensitive resin composition containing a colorant is used, it is preferable to use O-acyloxime compounds (including ketoximes). Examples of compounds that can be preferably used include O-acyloxime photopolymerization initiators represented by general formulas (18) and (19). Among these compounds, when a colorant is used at a high pigment concentration and when a cured film pattern is formed, it is preferable to use an O-acyloxime photopolymerization initiator having a molar extinction coefficient of 10,000 or more at 365 nm. In this invention, "photopolymerization initiator" is used to include sensitizers. The molar extinction coefficient can be measured, for example, using a UV-Vis-Near-Infrared Spectrophotometer "UH4150" (manufactured by Hitachi High-Tech Science Corporation).

[0122] [ka]

[0123] (In formula (18), R 18 , R 19 R independently represents an alkyl group of C1-C15, an aryl group of C6-C18, an arylalkyl group of C7-C20, or a heterocyclic group of C4-C12. 20 represents a C1-C15 alkyl group, a C6-C18 aryl group, or a C7-C20 arylalkyl group. Here, the alkyl and aryl groups may be substituted with C1-C10 alkyl groups, C1-C10 alkoxy groups, C1-C10 alkanoyl groups, or halogens, and the alkylene portion may contain unsaturated bonds, ether bonds, thioether bonds, or ester bonds. Furthermore, the alkyl group may be linear, branched, or cyclic.

[0124] [ka]

[0125] (In formula (19), R 21 and R 22R is independently a linear or branched alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, a cycloalkylalkyl group, or an alkylcycloalkyl group having 4 to 10 carbon atoms, or a phenyl group which may be substituted with an alkyl group having 1 to 6 carbon atoms. 23 Each of these R is independently a linear or branched alkyl or alkenyl group having 2 to 10 carbon atoms, and some of the -CH2- groups in the alkyl or alkenyl group may be substituted with -O- groups. Furthermore, these R 21 ~R 23 Some of the hydrogen atoms in the base may be substituted with halogen atoms.

[0126] The content of the photopolymerization initiator of component (v) is preferably 3 to 30 parts by weight, and more preferably 5 to 20 parts by weight, based on 100 parts by weight of the total of components (i) and (iv). When the blending ratio of component (v) is 3 parts by weight or more, good sensitivity is obtained and a sufficient photopolymerization rate can be achieved. When the blending ratio of component (v) is 30 parts by weight or less, moderate sensitivity can be obtained, so that the desired pattern line width and desired pattern edge can be obtained.

[0127] (Photosensitive resin composition) A dispersion for use in a photosensitive resin composition can be prepared by mixing and dispersing the above components (i) to (v) using an appropriate method.

[0128] (solvent) In addition to components (i) to (v), it is preferable to use a solvent as component (vi) in the photosensitive resin composition of the present invention. Examples of solvents include alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, and propylene glycol; terpenes such as α- or β-terpineol; ketones such as acetone, methyl ethyl ketone, cyclohexanone, and N-methyl-2-pyrrolidone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, and propylene glycol monoethyl ether. This includes glycol ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether; and acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, ethyl carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate. By dissolving and mixing these individually or in combination of two or more, a homogeneous solution-like composition can be obtained.

[0129] Furthermore, the photosensitive resin composition of the present invention may optionally contain additives other than component (i), such as epoxy resin, curing agents, curing accelerators, thermal polymerization inhibitors and antioxidants, plasticizers, fillers, leveling agents, defoamers, surfactants, and coupling agents.

[0130] Examples of thermal polymerization inhibitors and antioxidants include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine, and hindered phenol compounds.

[0131] Examples of the plasticizers mentioned above include dibutyl phthalate, dioctyl phthalate, and tricresyl phosphate.

[0132] Examples of the above-mentioned fillers include glass fiber, silica, mica, alumina, and the like.

[0133] Examples of the above-mentioned defoaming agents and leveling agents include silicone-based, fluorine-based, and acrylic compounds. Examples of surfactants include fluorine-based surfactants and silicone-based surfactants.

[0134] Examples of the coupling agents mentioned above include 3-(glycidyloxy)propyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, and 3-ureidopropyltriethoxysilane.

[0135] The photosensitive resin composition of the present invention preferably contains, in its solid component (which includes monomers that become solid components after curing), excluding the solvent component (vi), a total of 80% by mass or more, and more preferably 90% by mass or more, the alkali-soluble resin component (i), the (meth)acrylate resin component (ii), the light-shielding material component (iii), the photopolymerizable monomer component (iv), and the photopolymerization initiator component (v). The amount of solvent varies depending on the target viscosity, but is preferably 40 to 90% by mass of the total amount.

[0136] The photosensitive resin composition of the present invention can be obtained by mixing components (i) to (v) and any additives.

[0137] Furthermore, a cured film obtained by curing the photosensitive resin composition of the present invention can be obtained, for example, by applying a solution of the photosensitive resin composition to a substrate or the like, drying the solvent, and curing it by irradiating it with light (including ultraviolet light, radiation, etc.). By using a photomask or the like to create areas that are exposed to light and areas that are not, curing only the areas exposed to light and dissolving the other areas with an alkaline solution, a desired pattern can be obtained.

[0138] Furthermore, the cured film obtained by curing the photosensitive resin composition of the present invention can be used as a black matrix in a color filter. For example, it can be produced by forming a cured film with a thickness of 1.0 to 2.0 μm on a transparent substrate and then forming red, blue, and green pixels by photolithography after the cured film has been formed, or by impregnating the cured film with red, blue, and green inks using an inkjet process.

[0139] Furthermore, the cured film obtained by curing the photosensitive resin composition of the present invention can also be used as a black column spacer for a liquid crystal display device. For example, multiple portions with different film thicknesses can be created using a single black resist, with one portion functioning as a spacer and the other functioning as a black matrix.

[0140] The following are specific examples of each step in a method for forming a cured film by coating and drying a photosensitive resin composition according to one embodiment of the present invention.

[0141] Any known method can be used to apply the photosensitive resin composition to a substrate, such as the solution immersion method, spray method, roller coater, land coater, slit coater, or spinner machine. After applying the composition to the desired thickness using these methods, the solvent is removed (pre-bake) to form a film. Pre-bake is performed by heating in an oven, hot plate, vacuum drying, or a combination of these. The heating temperature and time during pre-bake can be appropriately selected depending on the solvent used, but for example, it is preferable to heat at 80 to 120°C for 1 to 10 minutes.

[0142] For exposure, visible light, ultraviolet light, far ultraviolet light, electron beams, X-rays, etc., can be used, but the wavelength range of the radiation is preferably 250 to 450 nm. Suitable developers for this alkaline development include aqueous solutions of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, tetramethylammonium hydroxide, etc. These developers can be appropriately selected according to the characteristics of the resin layer, and it is also effective to add surfactants as needed. The development temperature is preferably 20 to 35°C, and fine images can be precisely formed using commercially available developers or ultrasonic cleaners. After alkaline development, the image is usually washed with water. As for development methods, shower development, spray development, dip development, paddle development, etc., can be applied.

[0143] After development in this manner, heat treatment (post-bake) is performed at 180-250°C for 20-100 minutes. This post-bake is performed to improve the adhesion between the patterned cured film and the substrate, among other purposes. This is done by heating using an oven, hot plate, etc., similar to pre-bake. The patterned cured film of the present invention is formed through each step of the photolithography method. Then, polymerization or curing (sometimes referred to as curing collectively) is completed by heat, and a cured film with a desired pattern can be obtained. The curing temperature at this time is preferably 160-250°C.

[0144] In the cured film obtained by the above method, the polymerizable unsaturated group-containing alkali-soluble resin and the (meth)acrylate resin undergo phase separation, forming a thin layer on the outermost surface (the side not in contact with the substrate) of the cured film. As a result, a cured film with reduced reflectivity can be easily obtained without using a resin with a lower refractive index, and without separately providing an anti-reflective coating or the like on the outermost surface (the side not in contact with the substrate) of the formed cured film.

[0145] Furthermore, since the color filter of the present invention has a cured film obtained by curing the photosensitive resin composition of the present invention as a black matrix, good visibility can be obtained. [Examples]

[0146] The embodiments of the present invention will be specifically described below based on examples and comparative examples, but the present invention is not limited thereto.

[0147] The following explanation will begin with examples of the synthesis of (i) an alkali-soluble resin represented by general formula (1) and (ii) a (meth)acrylate resin represented by general formula (13). Unless otherwise noted, the evaluation of the resins in these synthesis examples was performed as follows. For various measuring instruments, the manufacturer's name is omitted from the second instance onward when the same model was used. In addition, in the examples, the glass substrates used to prepare the cured film substrates for measurement were all glass substrates that had undergone the same treatment.

[0148] [Solid content concentration] The weight of 1 g of the resin solution obtained in the synthesis example was impregnated into a glass filter [weight: W0 (g)] and weighed [W1 (g)]. After heating at 160°C for 2 hours, the weight [W2 (g)] was calculated from the following formula (1). Solid content concentration (weight%) = 100 × (W2-W0) / (W1-W0) (1)

[0149] [Acid value] The resin solution was dissolved in dioxane and titrated with a 1 / 10N-KOH aqueous solution using a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.) to determine the result.

[0150] [Molecular weight] The molecular weight was measured using gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation, solvent: tetrahydrofuran, columns: TSKgelSuper H-2000 (2) + TSKgelSuper H-3000 (1) + TSKgelSuper H-4000 (1) + TSKgelSuper H-5000 (1) (manufactured by Tosoh Corporation), temperature: 40℃, rate: 0.6 ml / min), and the weight-average molecular weight (Mw) was determined as a value converted to standard polystyrene (manufactured by Tosoh Corporation, PS-oligomer kit).

[0151] The abbreviations used in the synthesis examples and comparative synthesis examples are as follows: BPFE: Compound of fluorene-9,9-diyl group (reaction product of 9,9-bis(4-hydroxyphenyl)fluorene and epichlorohydrin (epoxy equivalent 250 g / eq)) AA: Acrylic acid BPDA: 3,3',4,4'-biphenyltetracarboxylic acid dianhydride THPA: Tetrahydrophthalic anhydride TEAB: Tetraethylammonium bromide PGMEA: Propylene glycol monomethyl ether acetate MAA: Methacrylic acid MMA: Methyl methacrylate CHMA: Cyclohexyl methacrylate GMA: Glycidyl methacrylate AIBN: Azobisisobutyronitrile TPP: Triphenylphosphine

[0152] [Synthesis Example 1] (Alkali-soluble resin) In a 1000 ml four-necked flask equipped with a reflux condenser, BPFE (224.00 g, 0.45 mol), AA (64.57 g, 0.90 mol), PGMEA (43.27 g), TEAB (0.94 g), and 2,6-di-tert-butyl-p-cresol (0.10 g) were charged and reacted by stirring at 100-105°C for 20 hours. Next, PGMEA (246.32 g), BPDA (65.90 g, 0.225 mol), and THPA (34.08 g, 0.225 mol) were added and stirred under heating at 120-125°C for 6 hours to obtain alkali-soluble resin (i) (solid content concentration: 56.5% by mass, weight-average molecular weight (Mw): 3600, acid value (based on solid content): 99.5 mg KOH / g).

[0153] [Synthesis Example 2] ((meth)acrylate resin) MAA (61.98 g, 0.72 mol), MMA (43.25 g, 0.43 mol), CHMA (48.45 g, 0.29 mol), AIBN (7.09 g), and diethylene glycol dimethyl ether (432 g) were charged into a 1000 ml four-necked flask equipped with a nitrogen inlet tube and reflux condenser, and polymerization was carried out by stirring at 80-85°C under a nitrogen stream for 8 hours. Furthermore, GMA (73.69 g, 0.52 mol), TPP (1.76 g), and 2,6-di-tert-butyl-p-cresol (0.10 g) were charged into the four-necked flask and stirred at 80-85°C for 16 hours to obtain (meth)acrylate resin (ii)-1 (solid content concentration: 35.5% by mass, weight-average molecular weight (Mw): 21500, acid value (based on solid content): 50 mg KOH / g).

[0154] [Synthesis Example 3] ((meth)acrylate resin) MAA (61.98g, 0.72 mol), MMA (43.25g, 0.43 mol), CHMA (48.45g, 0.29 mol), AIBN (21.28g), and diethylene glycol dimethyl ether (458g) were charged into a 1000 ml four-necked flask equipped with a nitrogen inlet tube and reflux condenser, and polymerization was carried out by stirring at 80-85°C under a nitrogen stream for 8 hours. Furthermore, GMA (73.69 g, 0.52 mol), TPP (1.76 g), and 2,6-di-tert-butyl-p-cresol (0.10 g) were charged into the four-necked flask and stirred at 80-85°C for 16 hours to obtain (meth)acrylate resin (ii)-2 (solid content concentration: 35.6% by mass, weight-average molecular weight (Mw): 6500, acid value (based on solid content): 52 mg KOH / g).

[0155] [Comparative Synthesis Example] ((meth)acrylate resin) In a 1000 ml four-necked flask equipped with a nitrogen inlet tube and reflux condenser, MMA (84.10 g, 0.84 mol), CHMA (141.41 g, 0.84 mol), AIBN (8.28 g), and diethylene glycol dimethyl ether (430 g) were charged and stirred for 8 hours under a nitrogen stream at 80-85°C to obtain (meth)acrylate resin (ii)-3 (solid content concentration: 35.3 mass%, weight-average molecular weight (Mw): 19300).

[0156] The photosensitive resin compositions of Examples 1-5 and Comparative Examples 1 and 2 were prepared using the formulation amounts (values ​​are in mass%) listed in Table 1. The formulation components used in the table are as follows:

[0157] (i) Alkali-soluble resin obtained in Synthesis Example 1 (solid content concentration 56.5% by mass) (ii)-1: (meth)acrylate resin obtained in Synthesis Example 2 (solid content concentration 35.5% by mass) (ii)-2: (meth)acrylate resin obtained in Synthesis Example 3 (solid content concentration 35.3% by mass) (ii)-3: (meth)acrylate resin obtained in the comparative synthesis example (solid content concentration 35.6%) (iii) PGMEA dispersion containing 20.0% by mass of carbon black and 5.0% by mass of polymer dispersant (solid content 25.0%, average secondary particle size of carbon black 162 nm) (iv) Dipentaerythritol hexaacrylate (v) : Irgacure OXE02 (manufactured by BASF Japan, "Irgacure" is a registered trademark of the company) (vi) : Propylene glycol monomethyl ether acetate

[0158] [Table 1]

[0159] [evaluation] The following evaluations were performed using the photosensitive resin compositions of Examples 1-5 and Comparative Examples 1 and 2. Furthermore, the glass substrates used to prepare the cured films for evaluation were all treated with the same process.

[0160] (Preparation of cured films for adhesion and linearity evaluation) The photosensitive resin compositions shown in Table 1 were pre-treated with a low-pressure mercury lamp at a wavelength of 254 nm and an illuminance of 1000 mJ / cm². 2 A 125mm x 125mm glass substrate "#1737" (manufactured by Corning) (hereinafter referred to as "glass substrate"), whose surface had been cleaned by irradiation with ultraviolet light, was coated using a spin coater to achieve a film thickness of 1.5 μm after heat curing. A cured film was then prepared by pre-baking at 90°C for 1 minute using a hot plate. Subsequently, through a negative photomask for pattern formation, the i-line irradiance was 30 mW / cm². 2 Exposure was performed by irradiating the sample with ultraviolet light at a wavelength of 365 nm using a high-pressure mercury lamp.

[0161] The exposed cured film described above was developed at 23°C using a 0.15% sodium carbonate aqueous solution, and then fully cured (post-bake) using a hot air dryer at 230°C for 30 minutes to obtain a cured film for evaluating adhesion and linearity.

[0162] [Adhesion evaluation] (Evaluation method) The pattern line width after final hardening (post-bake) was confirmed using an optical microscope, "ECLIPSE LV100" (manufactured by Nikon Corporation).

[0163] (Evaluation Criteria) ○: Patterns with L / S (line width / space width) of 20 μm / 20 μm or larger are formed without any residue. ×: Patterns where L / S (line width / space width) is less than 20 μm / 20 μm are not formed, or where pattern trailing or residue is noticeable.

[0164] [Linearity Evaluation] (Evaluation method) The linearity of the fine line pattern of the cured film after post-bake curing was confirmed using an optical microscope, "ECLIPSE LV100".

[0165] (Evaluation Criteria) ○: No peeling or chipping of the fine line pattern on the glass substrate, and no jagged edges on the pattern ends are observed. ×: Peeling or chipping of the fine line pattern on the glass substrate, and jagged edges on the pattern are observed.

[0166] (Preparation of cured films for reflectance, optical density, and appearance evaluation) The photosensitive resin compositions shown in Table 1 were applied to a glass substrate using a spin coater to achieve a film thickness of 1.5 μm after heat curing, and a cured film was prepared by pre-baking at 90°C for 1 minute using a hot plate. Subsequently, without using a negative photomask for pattern formation, the i-line illuminance was 30 mW / cm². 2 Exposure was performed by irradiating the sample with ultraviolet light at a wavelength of 365 nm using a high-pressure mercury lamp.

[0167] The exposed cured film described above was developed at 23°C using a 0.15% sodium carbonate aqueous solution, and then fully cured (post-baked) using a hot air dryer at 230°C for 30 minutes to obtain a cured film for evaluation of reflectivity, optical density, and appearance.

[0168] [Reflectance evaluation] (Evaluation method) For a substrate with a cured film for reflectivity evaluation, the reflectivity on the cured film side (opposite side from the glass substrate) was measured at an incident angle of 2° using a UV-Vis-Near-Infrared Spectrophotometer "UH4150" (manufactured by Hitachi High-Tech Science Co., Ltd.).

[0169] (Evaluation Criteria) ◎: The reflectivity of the hardened film surface is 5.5 or less. ○: The reflectance of the hardened film surface is greater than 5.5 and less than or equal to 6.5. △: The reflectance of the hardened film surface is greater than 6.5 and less than or equal to 7.5. ×: The reflectivity of the hardened film surface is greater than 7.5.

[0170] [Exterior evaluation] The cured film used for visual evaluation was observed visually for whitening, surface unevenness, and the presence or absence of foreign matter.

[0171] (Evaluation Criteria) ◎: No whitening, discoloration, or foreign matter is observed. ○: Whitening, discoloration, or foreign matter is observed in less than 1 / 4 of the surface area. △: Whitening, discoloration, or foreign matter is observed in less than one-third of the surface area. ×: Whitening, discoloration, or foreign matter is observed throughout.

[0172] [Optical Fluorescence Evaluation] (Evaluation method) The optical density (OD) of the cured film, prepared in the same manner as the cured film used for optical density (OD) evaluation, was evaluated using a Macbeth transmission densitometer. Furthermore, the film thickness of the cured film formed on the substrate was measured, and the value obtained by dividing the optical density (OD) by the film thickness was defined as OD / μm.

[0173] The optical density (OD) was calculated using the following formula (1). Optical density (OD)=-log 10 T (1) (T indicates transmittance)

[0174] The evaluation results are shown in Table 2.

[0175] [Table 2]

[0176] As is clear from the results of Examples 1 to 5 and Comparative Examples 1 and 2 above, it was found that by using a photosensitive resin composition containing the alkali-soluble resin (i) and (meth)acrylate resin (ii) of the present invention, the reflectance of the cured film can be reduced, and both high light shielding and high-definition pattern formation can be achieved.

[0177] Furthermore, it was found that by using two different types of resin, a photosensitive resin composition can be obtained that reduces reflectivity in a simple manner and achieves both high light-shielding properties and high-definition pattern formation. [Industrial applicability]

[0178] The photosensitive resin composition of the present invention provides a photosensitive resin composition having high light-shielding properties and low reflectivity, as well as a cured film and a color filter using the same. Furthermore, the cured film of the present invention, when formed on a transparent substrate, contributes to achieving low reflectivity on the coated surface side of the cured film, making it useful for various display devices and sensors such as solid-state image sensors.

Claims

1. A polymerizable unsaturated group-containing alkali-soluble resin (i) with a weight-average molecular weight of 2500 or more is obtained by reacting an epoxy compound having two or more phenylglycidyl ether groups in its molecule with an unsaturated group-containing monocarboxylic acid with a dicarboxylic acid or tricarboxylic acid or their acid monoanhydride, and a tetracarboxylic acid or its acid dianhydride. (Meth)acrylate resin (ii) having a weight-average molecular weight of 10,000 or more and 100,000 or less, having carboxyl groups and polymerizable unsaturated groups in its side chains (excluding epoxy acrylate obtained by copolymerizing an epoxy group-containing acrylic monomer with a fluorine monomer copolymerizable with the epoxy group-containing acrylic monomer, reacting the copolymer with an ethylenically unsaturated group-containing carboxylic acid compound, and then further reacting it with a polybasic acid anhydride), It contains as a resin component, A photosensitive resin composition comprising, as an essential component, a light-shielding material (iii) selected from the group consisting of black organic pigments, black inorganic pigments, or mixed organic pigments.

2. The polymerizable unsaturated group-containing alkali-soluble resin (i) has a weight-average molecular weight of 2,500 or more and 100,000 or less. The photosensitive resin composition according to claim 1, wherein the mass of (ii) is 1 to 60% by mass of the total mass of (i) and (ii).

3. The photosensitive resin composition according to claim 1 or claim 2, wherein the polymerizable unsaturated group-containing alkali-soluble resin (i) has a structure represented by general formula (1). 【Chemistry 1】 (In formula (1), R １ is independently a hydrocarbon group having 2 to 4 carbon atoms, R ２ is independently a hydrocarbon group having 1 to 3 carbon atoms, R ３ is independently a hydrogen atom or a methyl group, X is independently a divalent organic group having 1 to 20 carbon atoms which may contain a hetero element inside, -CO-, -SO ２ -, -C(CF ３ ) ２ -, -CH ２ -, -C(CH ３ ) ２ -, -Si(CH ３ ) ２ -, -O-, a fluorene-9,9-diyl group represented by the general formula (2) or a single bond, Y is a tetravalent carboxylic acid residue, and Z is independently a hydrogen atom or a substituent represented by the general formula (3). However, at least one of Z is a substituent represented by the general formula (3), G is independently a hydrogen atom or a substituent represented by the general formula (4), a is independently a number from 0 to 10, b is independently a number from 0 to 4, and n is an integer with an average value of 1 to 20.) 【Chemistry 2】 【Transformation 3】 【Chemistry 4】 (In formulas (3) and (4), R ４ , R ６ R is a hydrogen atom or a methyl group, ５ , R ７ (where is a hydrocarbon group having 2 to 4 carbon atoms, L is a divalent or trivalent carboxylic acid residue, c and f are numbers of 0 or 1, d and e are numbers of 0, 1 or 2, and d+e is a number of 1 or 2.)

4. The photosensitive resin composition according to any one of claims 1 to 3, wherein the (meth)acrylate resin (ii) is a (meth)acrylate resin having a carboxyl group and a polymerizable unsaturated group in its side chain, obtained by reacting a (meth)acrylate having an epoxy group represented by general formula (7) in a copolymer of a (meth)acrylate represented by general formula (5) and (meth)acrylic acid represented by general formula (6). 【Transformation 5】 (In formula (5), R ８ R is a hydrogen atom or a methyl group, ９ is a hydrocarbon group having 1 to 20 carbon atoms, and the R ９ (It may contain etheric oxygen atoms or urethane bonds internally.) 【Transformation 6】 (In formula (6), R １０ (This is either a hydrogen atom or a methyl group.) 【Transformation 7】 (In formula (7), R １１ R is a hydrogen atom or a methyl group, １２ (where g is a divalent hydrocarbon group having 2 to 10 carbon atoms, and g is the number 0 or 1.)

5. The photosensitive resin composition according to any one of claims 1 to 4 further comprises: (iv) A photopolymerizable monomer having at least two polymerizable unsaturated groups, (v) Photopolymerization initiator, A photosensitive resin composition containing as an essential component.

6. A cured film obtained by curing the photosensitive resin composition according to any one of claims 1 to 5.

7. A color filter having the cured film described in claim 6 as a black matrix.

Images