JP2024068130A - Photosensitive resin composition for black resist, light-shielding film, color filter, touch panel and display device - Google Patents

Abstract

[Problem] To provide a photosensitive resin composition for black resist, which can provide a cured film with high light-shielding properties and reduced reflectance on both the glass surface side and the film surface side. [Solution] A photosensitive resin composition for black resist, comprising (A) an unsaturated group-containing photosensitive resin, (B) a photopolymerizable compound, (C) a photopolymerization initiator, (D) a light-shielding component, (E) silica particles, (F) a dispersant, and (G) a solvent, wherein the acid value and amine value of the (F) dispersant are both 10 to 80 mgKOH/g or less, the mass ratio of the (F) dispersant to the (E) silica particles is 0.02 to 0.60, and the (G) solvent comprises propylene glycol monomethyl ether acetate and a solvent having a vapor pressure of less than 250 Pa at 20°C (excluding solvents represented by general formula (1)), RO-(CH2CH2O)n-R ... (1) (R represents an alkyl group or aryl group which may have a substituent, and n is an integer of 2 to 5). [Selected Figure] None

Description

The present invention relates to a photosensitive resin composition for black resist, a light-shielding film obtained by curing the composition, a color filter and a touch panel having the light-shielding film, and a display device having the color filter or touch panel.

In recent years, with the development of mobile terminals, there has been an increase in display devices with touch panels or liquid crystal panels for use outdoors or in vehicles. In such display devices, the outer frame of the touch panel is provided with a light-shielding film to block light leakage from the periphery of the liquid crystal panel on the back, and the liquid crystal panel is provided with a light-shielding film (black matrix) to prevent light leakage from the screen when displaying black and to prevent color mixing between adjacent color resists.

A black matrix is required to have high light blocking properties as well as low reflectance. For example, Patent Document 1 describes that the use of hydrophobic silica microparticles dispersed in a specific urethane dispersant makes it possible to achieve both high light blocking properties and low reflectance in the black matrix. In Patent Document 1, when evaluating low reflectance, the reflectance from the glass surface of a glass substrate coated with and cured with a black photosensitive resin composition is measured.

JP 2015-161815 A

As described in Patent Document 1, various photosensitive resin compositions have been investigated to obtain a cured film that has high light-shielding properties and reduces the reflectance from the glass surface. On the other hand, according to the knowledge of the present inventors, there is a demand for cured films such as black matrices to have a reduced reflectance not only from the glass surface but also from the film surface side.

The present invention has been made in consideration of these points, and aims to provide a photosensitive resin composition for black resist that can produce a cured film with high light-shielding properties and reduced reflectance on both the glass surface side and the film surface side, a light-shielding film obtained by curing the composition, a color filter and touch panel having the light-shielding film, and a display device having the color filter or touch panel.

（一般式（２）中、Ｒ_１、Ｒ_２、Ｒ_３およびＲ_４は、それぞれ独立して水素原子、炭素数１以上５以下のアルキル基またはハロゲン原子であり、Ｘは－ＣＯ－、－ＳＯ_２－、－Ｃ（ＣＦ_３）_２－、－Ｓｉ（ＣＨ_３）_２－、－ＣＨ_２－、－Ｃ（ＣＨ_３）_２－、－Ｏ－、一般式（３）で表されるフルオレン－９，９－ジイル基または単結合であり、ｌは０以上１０以下の整数である。）

［３］前記（Ｆ）分散剤は、アルキルアンモニウム塩構造を有する高分子化合物である、［１］または［２］に記載のブラックレジスト用感光性樹脂組成物。
［４］前記（Ｇ）溶剤は、
２３℃における比誘電率が１０．０以上３０．０以下の溶剤（ただし、前記第２溶剤を除く）である第３－１溶剤を含むか、または、
前記第２溶剤は、２３℃における比誘電率が１０．０未満である溶剤と、２３℃における比誘電率が１０．０以上３０．０以下である第３－２溶剤と、を含む、
［１］～［３］に記載のブラックレジスト用感光性樹脂組成物。
［５］前記（Ｇ）溶剤は、前記第３－１溶剤を含む、
［４］に記載のブラックレジスト用感光性樹脂組成物。
［６］前記（Ｅ）シリカ粒子の平均粒子径は、１ｎｍ以上１００ｎｍ以下である、［１］～［５］のいずれかに記載のブラックレジスト用感光性樹脂組成物。
［７］前記（Ｄ）遮光成分の全質量（ｍＤ）に対する前記（Ｅ）シリカ粒子の全質量（ｍＥ）の割合（ｍＥ／ｍＤ）は、０．０１以上０．２０以下である、［１］～［６］のいずれかに記載のブラックレジスト用感光性樹脂組成物。
［８］前記第２溶剤は、２０℃における蒸気圧が１００Ｐａ未満の溶剤である、［１］～［７］のいずれかに記載のブラックレジスト用感光性樹脂組成物。
［９］前記第２溶剤は、３－メトキシ－３－メチル－１－ブチルアセテート、３－メトキシ－３－メチル－１－ブタノール、およびプロピレングリコールジアセテートからなる群から選択される少なくとも一種の溶剤を含む、［１］～［８］のいずれかに記載の感光性樹脂組成物。
［１０］前記ブラックレジスト用感光性樹脂組成物を硬化することにより、膜面側の反射率が６．５％以下である遮光膜を得ることができる、［１］～［９］のいずれかに記載のブラックレジスト用感光性樹脂組成物。
［１１］前記ブラックレジスト用感光性樹脂組成物を硬化することにより、膜面側の反射率が５．５％以下である遮光膜を得ることができる、［１］～［１０］のいずれかに記載のブラックレジスト用感光性樹脂組成物。 One aspect of the present invention for solving the above problems relates to a photosensitive resin composition for black resist according to the following [1] to [9].
[1] (A) an unsaturated group-containing photosensitive resin;
(B) a photopolymerizable compound having at least two unsaturated bonds;
(C) a photopolymerization initiator;
(D) at least one light-shielding component selected from the group consisting of black pigments, mixed color pigments, and light-shielding materials;
(E) silica particles;
(F) a dispersant; and
(G) a solvent,
The (F) dispersant has an acid value and an amine value, and both of the acid value and the amine value are 10 mgKOH/g or more and 80 mgKOH/g or less,
a ratio (mF/mE) of the total mass (mF) of the dispersant (F) to the total mass (mE) of the silica particles (E) is 0.02 or more and 0.60 or less;
The (G) solvent includes a first solvent which is propylene glycol monomethyl ether acetate, and a second solvent having a vapor pressure of less than 250 Pa at 20° C. (the second solvent excludes solvents represented by the following general formula (1)).
RO-(CH ₂ CH ₂ O)n-R... (1)
(In general formula (1), R independently represents an alkyl group or an aryl group which may have a substituent, and n is an integer of 2 or more and 5 or less.)
Photosensitive resin composition for black resist.
[2] The photosensitive resin composition for black resist according to [1], wherein the (A) unsaturated group-containing photosensitive resin is an unsaturated group-containing photosensitive resin obtained by further reacting a reaction product of an epoxy compound having two glycidyl ether groups, which is derived from a bisphenol represented by the following general formula (2), with (meth)acrylic acid, with a polybasic carboxylic acid or an anhydride thereof:

(In general formula (2), R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogen atom; X represents -CO-, -SO ₂ -, -C(CF ₃ ) ₂ -, -Si(CH ₃ ) ₂ -, -CH ₂ -, -C(CH ₃ ) ₂ -, -O-, a fluorene-9,9-diyl group represented by general formula (3) or a single bond; and l represents an integer of 0 to 10.)

[3] The photosensitive resin composition for a black resist according to [1] or [2], wherein the dispersant (F) is a polymer compound having an alkyl ammonium salt structure.
[4] The (G) solvent is
A third-1 solvent (excluding the second solvent) having a dielectric constant of 10.0 or more and 30.0 or less at 23° C. is included, or
The second solvent includes a solvent having a relative dielectric constant of less than 10.0 at 23° C. and a third-2 solvent having a relative dielectric constant of 10.0 or more and 30.0 or less at 23° C.;
The photosensitive resin composition for black resist according to any one of [1] to [3].
[5] The (G) solvent includes the 3-1 solvent,
The photosensitive resin composition for black resist according to [4].
[6] The photosensitive resin composition for a black resist according to any one of [1] to [5], wherein the average particle size of the silica particles (E) is 1 nm or more and 100 nm or less.
[7] The photosensitive resin composition for black resist according to any one of [1] to [6], wherein a ratio (mE/mD) of the total mass (mE) of the silica particles (E) to the total mass (mD) of the light-shielding component (D) is 0.01 or more and 0.20 or less.
[8] The photosensitive resin composition for a black resist according to any one of [1] to [7], wherein the second solvent has a vapor pressure of less than 100 Pa at 20° C.
[9] The photosensitive resin composition according to any one of [1] to [8], wherein the second solvent includes at least one solvent selected from the group consisting of 3-methoxy-3-methyl-1-butyl acetate, 3-methoxy-3-methyl-1-butanol, and propylene glycol diacetate.
[10] The photosensitive resin composition for a black resist according to any one of [1] to [9], which can obtain a light-shielding film having a reflectance of 6.5% or less on the film surface side by curing the photosensitive resin composition for a black resist.
[11] The photosensitive resin composition for a black resist according to any one of [1] to [10], which can obtain a light-shielding film having a reflectance of 5.5% or less on the film surface side by curing the photosensitive resin composition for a black resist.

Another aspect of the present invention for solving the above-mentioned problems relates to a light-shielding film according to the following item [12].
[12] A light-shielding film obtained by curing the photosensitive resin composition for black resist according to any one of [1] to [11].

Another aspect of the present invention for solving the above problems relates to a color filter, a touch panel, and a display device according to the following items [13] to [16].
[13] A color filter having the light-shielding film according to [12] as a black matrix.
[14] A touch panel having the light-shielding film according to [12].
[15] A display device having the color filter according to [13].
[16] A display device having the touch panel according to [14].

The present invention provides a photosensitive resin composition for black resist that can provide a cured film with high light-shielding properties and reduced reflectance on both the glass surface side and the film surface side, a light-shielding film obtained by curing the composition, a color filter and a touch panel having the light-shielding film, and a display device having the color filter or touch panel.

The present invention will be described in detail below. The photosensitive resin composition for black resist of the present invention (hereinafter also referred to as "photosensitive resin composition") contains (A) an unsaturated group-containing photosensitive resin, (B) a photopolymerizable compound having at least two unsaturated bonds, (C) a photopolymerization initiator, (D) one type of light-shielding component which is a black pigment, a mixed color pigment, or a light-shielding material, (E) silica particles, (F) a dispersant, and (G) a solvent.

In the present invention, the (F) dispersant has an acid value and an amine value, and both of the acid value and the amine value are 10 mgKOH/g or more and 80 mgKOH/g or less. The ratio (mF/mE) of the total mass (mF) of the (F) dispersant to the total mass (mE) of the (E) silica particles is 0.02 or more and 0.60 or less. The (G) solvent includes a first solvent which is propylene glycol monomethyl ether acetate, and a second solvent having a vapor pressure of less than 250 Pa at 20° C. (the second solvent excludes the solvent represented by the following general formula (1)).
RO-(CH ₂ CH ₂ O)n-R... (1)
In formula (1), R independently represents an alkyl group or an aryl group which may have a substituent, and n is an integer of 2 or more and 5 or less.

Components (A) through (G) are explained below.

1. Component (A) Component (A) is an unsaturated group-containing photosensitive resin. Component (A) preferably has a polymerizable unsaturated group and an acidic group for expressing alkali solubility in one molecule, and more preferably contains both a polymerizable unsaturated group and a carboxy group. As long as it is the above resin, it can be widely used without any particular limitation.

Examples of the unsaturated group-containing photosensitive resin include an epoxy (meth)acrylate acid adduct obtained by reacting an epoxy compound having two glycidyl ether groups derived from a bisphenol with (meth)acrylic acid, and then reacting the resulting compound having a hydroxy group with a polybasic carboxylic acid or its anhydride. An epoxy compound derived from a bisphenol means an epoxy compound obtained by reacting a bisphenol with an epihalohydrin, or an equivalent thereof. Note that "(meth)acrylic acid" is a general term for acrylic acid and methacrylic acid, and means either or both of these.

Component (A) is preferably a bisphenol-type epoxy compound represented by the following general formula (2):

In general formula (2), R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogen atom; X represents -CO-, -SO ₂ -, -C(CF ₃ ) ₂ -, -Si(CH ₃ ) ₂ -, -CH ₂ -, -C(CH ₃ ) ₂ -, -O-, a fluorene-9,9-diyl group represented by general formula (3) or a single bond; and l represents an integer of 0 to 10.

The bisphenol-type epoxy compound represented by the general formula (2) is an epoxy compound having two glycidyl ether groups obtained by reacting bisphenols with epichlorohydrin. This reaction usually involves oligomerization of a diglycidyl ether compound, so the bisphenol-type epoxy compound represented by the general formula (2) includes an epoxy compound containing two or more bisphenol skeletons.

Examples of bisphenols used in this reaction 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-dimethylphenyl)hexafluoropropane, bis(4-hydroxyphenyl)hexafluoropropane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)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 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-methylphenyl)fluorene, 9,9-bis(4-hydroxy -3-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, etc. Among these, bisphenols having a fluorene-9,9-diyl group are preferred.

Examples of (a) dicarboxylic or tricarboxylic acid monoanhydrides that react with the hydroxyl groups in the epoxy (meth)acrylate molecule obtained by reacting such an epoxy compound with (meth)acrylic acid include acid monoanhydrides of chain hydrocarbon dicarboxylic or tricarboxylic acids, acid monoanhydrides of alicyclic dicarboxylic or tricarboxylic acids, and acid monoanhydrides of aromatic dicarboxylic or tricarboxylic acids. Examples of chain hydrocarbon dicarboxylic or tricarboxylic acids 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 the like, and dicarboxylic or tricarboxylic acids having any substituent introduced therein. Examples of alicyclic dicarboxylic or tricarboxylic acids include cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, norbornanedicarboxylic acid, and the like, and dicarboxylic or tricarboxylic acids having any substituent introduced therein. Examples of aromatic dicarboxylic acids or tricarboxylic acids include phthalic acid, isophthalic acid, trimellitic acid, etc., and these dicarboxylic acids or tricarboxylic acids to which any substituent has been introduced. These dicarboxylic acids or tricarboxylic acids are preferably acid monoanhydrides.

Examples of the (b) tetracarboxylic acid dianhydride to be reacted with the epoxy (meth)acrylate include a chain hydrocarbon tetracarboxylic acid dianhydride, an alicyclic tetracarboxylic acid dianhydride, or an aromatic tetracarboxylic acid dianhydride. Examples of the chain hydrocarbon tetracarboxylic acid dianhydride include butane tetracarboxylic acid, pentane tetracarboxylic acid, hexane tetracarboxylic acid, and the like, and these tetracarboxylic acids to which an arbitrary substituent has been introduced. Examples of the alicyclic tetracarboxylic acid dianhydride include cyclobutane tetracarboxylic acid, cyclopentane tetracarboxylic acid, cyclohexane tetracarboxylic acid, cycloheptane tetracarboxylic acid, norbornane tetracarboxylic acid, and the like, and these tetracarboxylic acids to which an arbitrary substituent has been introduced. Examples of the aromatic tetracarboxylic acid dianhydride include pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, biphenyl ether tetracarboxylic acid, and these tetracarboxylic acids to which an arbitrary substituent has been introduced. It is preferable that these tetracarboxylic acids are acid dianhydrides.

The molar ratio (a)/(b) of (a) dicarboxylic or tricarboxylic acid monoanhydride to (b) tetracarboxylic acid dianhydride to be reacted with epoxy (meth)acrylate 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 within the above range, the molecular weight of the (A) component can be adjusted to improve the patterning properties of the photosensitive resin composition. Note that the smaller the molar ratio (a)/(b), the larger the molecular weight and the lower the alkali solubility tends to be.

The method of reaction between the epoxy compound and (meth)acrylic acid, and the method of reaction between the epoxy (meth)acrylate obtained by this reaction and the polybasic carboxylic acid or its acid anhydride are not particularly limited, and known methods can be adopted. The unsaturated group-containing photosensitive resin synthesized by the above reaction preferably has a weight average molecular weight (Mw) of 2000 to 10000. The unsaturated group-containing photosensitive resin synthesized by the above reaction preferably has an acid value of 30 mgKOH/g to 200 mgKOH/g. The acid value can be determined by dissolving the resin solution in dioxane and titrating it with a 1/10N-KOH aqueous solution using, for example, a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.). The weight average molecular weight (Mw) of the unsaturated group-containing photosensitive resin can be measured, for example, using a gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation).

Another preferred example of component (A) is a copolymer of (meth)acrylic acid, (meth)acrylic acid esters, etc., and includes a resin having a (meth)acryloyl group and a carboxy group. Examples of the above resin include an alkali-soluble resin containing a polymerizable unsaturated group obtained by reacting a copolymer obtained by copolymerizing (meth)acrylic acid esters including glycidyl (meth)acrylate in a solvent with the copolymer, and finally reacting with an anhydride of a dicarboxylic acid or tricarboxylic acid. The above copolymer can be based on JP 2014-111722 A, which is composed of 20 to 90 mol% of repeating units derived from diester glycerol in which hydroxyl groups at both ends are esterified with (meth)acrylic acid, and 10 to 80 mol% of repeating units derived from one or more polymerizable unsaturated compounds copolymerizable therewith, and has a number average molecular weight (Mn) of 2000 to 20,000 and an acid value of 35 to 120 mg KOH/g, and JP 2018-141968 A, which is a polymer having a weight average molecular weight (Mw) of 3000 to 50,000 and an acid value of 30 to 200 mg/KOH, including a unit derived from a (meth)acrylic acid ester compound and a unit having a (meth)acryloyl group and a di- or tricarboxylic acid residue.

Component (A) may be used alone or in combination of two or more types.

The amount of component (A) is preferably 5% by mass or more and 70% by mass or less, more preferably 5% by mass or more and 60% by mass or less, and even more preferably 10% by mass or more and 50% by mass or less, based on the total mass of the solids.

2. Component (B) Component (B) is a photopolymerizable compound having at least two or more unsaturated bonds. Examples of component (B) 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, dipentaerythritol di(meth)acrylate, penta ... Examples of the photopolymerizable compound include (meth)acrylic acid esters such as taerythritol 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, and dendritic polymers having (meth)acrylic groups as compounds having ethylenic double bonds. The photopolymerizable compound (B) may be used alone or in combination of two or more of these. The photopolymerizable compound (B) can also play a role in crosslinking the molecules of the component (A), and it is preferable that the component (B) has three or more unsaturated bonds in order to exert this function. Furthermore, the component (B) preferably has an acrylic equivalent, calculated by dividing the molecular weight by the number of (meth)acrylic groups in one molecule, of 50 or more and 300 or less, and more preferably 80 or more and 200 or less. The component (B) does not have a free carboxy group.

Examples of dendritic polymers having (meth)acryloyl groups that can be used as component (B) include dendritic polymers obtained by adding a polyvalent mercapto compound to some of the carbon-carbon double bonds in the (meth)acryloyl group of a polyfunctional (meth)acrylate. Specifically, these include dendritic polymers obtained by reacting the (meth)acryloyl group of a polyfunctional (meth)acrylate represented by the following general formula (4) with a polyvalent mercapto compound represented by the following general formula (5).

(In general formula (4), _R5 is a hydrogen atom or a methyl group, and _R6 is the remaining portion obtained by donating n hydroxy groups out of the k hydroxy groups of _R7 (OH) _k to the ester bond in the formula. _R7 (OH) _k is preferably 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 through ether bonds by dehydration condensation of the alcohol, or an ester of such a polyhydric alcohol or polyhydric alcohol ether with a hydroxy acid. k and n independently represent an integer of 2 to 20, but k≧n.)

(In general formula (5), _R8 is a single bond or a divalent to hexavalent hydrocarbon group having 1 to 6 carbon atoms, and m is 2 when _R8 is a single bond, and is the same as the valence of _R8 when _R8 is a divalent to hexavalent group.)

Examples of polyfunctional (meth)acrylates represented by general formula (4) 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 polyfunctional (meth)acrylates may be used alone or in combination of two or more.

Examples of polyvalent mercapto compounds represented by general formula (5) include trimethylolpropane tri(mercaptoacetate), trimethylolpropane tri(mercaptopropionate), pentaerythritol tetra(mercaptoacetate), pentaerythritol tri(mercaptoacetate), pentaerythritol tetra(mercaptopropionate), dipentaerythritol hexa(mercaptoacetate), dipentaerythritol hexa(mercaptopropionate), etc. These polyvalent mercapto compounds may be used alone or in combination of two or more.

The blending ratio of the (A) component to the (B) component is preferably 30/70 to 90/10, more preferably 60/40 to 80/20, in terms of the weight ratio (A)/(B). When the blending ratio of the (A) component is 30/70 or more, the cured product after photocuring is less likely to become brittle, and the acid value of the coating film is less likely to become low in the unexposed areas, so that the decrease in solubility in an alkaline developer can be suppressed. Therefore, problems such as jagged pattern edges and lack of sharpness are less likely to occur. In addition, when the blending ratio of the (A) component is 90/10 or less, the proportion of photoreactive functional groups in the resin is sufficient, so that the desired crosslinked structure can be formed. In addition, since the acid value of the resin component is not too high, the solubility in an alkaline developer in the exposed areas is less likely to become high, so that the formed pattern is less likely to be narrower than the target line width, and pattern loss can be suppressed.

3. Component (C) Component (C) is a photopolymerization initiator. Examples of component (C) 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, benzoin ethers such as benzil, benzoin, benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether, 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, and the like. biimidazole compounds such as 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazole, and 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4-oxadiazole; halomethylthiazole compounds such as 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)-4,6-bis(trichloromethyl)-1,3,5-triazine, and 2-(4-methoxynaphthalene)-4,6-bis(trichloromethyl)-1,3,5-triazine. halomethyl-S-triazines such as 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. Dinyl compounds: 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)butan-1-oneoxime-O-acetate acetate, 4-ethoxy-2-methylphenyl-9-ethyl-6-nitro-9H-carbazol-3-yl-O-acetyloxime and other O-acyloxime compounds; sulfur compounds such as benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone; anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone; organic peroxides such as azobisisobutyronitrile, benzoyl peroxide, cumene peroxide; thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, and other tertiary amines such as triethanolamine and triethylamine. Of these, O-acyloxime compounds are preferred. These photopolymerization initiators may be used alone or in combination of two or more kinds.

Examples of O-acyloxime compounds that can be preferably used include O-acyloxime photopolymerization initiators represented by the following general formula (6) and the following general formula (7). Among these compounds, when a light-shielding component is used at a high concentration, it is preferable to use an O-acyloxime photopolymerization initiator having a molar absorption coefficient of 10,000 or more at 365 nm. In the present invention, the term "photopolymerization initiator" is used to include a sensitizer.

(In general formula (6), R ₉ and R ₁₀ each independently represent an alkyl group having 1 to 15 carbon atoms, an aryl group having 6 to 18 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, or a heterocyclic group having 4 to 12 carbon atoms; and R ₁₁ represents an alkyl group having 1 to 15 carbon atoms, an aryl group having 6 to 18 carbon atoms, or an arylalkyl group having 7 to 20 carbon atoms. Here, the alkyl group and the aryl group may be substituted with an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkanoyl group having 1 to 10 carbon atoms, or a halogen, and the alkylene portion may contain an unsaturated bond, an ether bond, a thioether bond, or an ester bond. In addition, the alkyl group may be any of a linear, branched, and cyclic alkyl group.)

(In general formula (7), R ₁₂ and R ₁₃ each independently represent 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. R ₁₄ each independently represent a linear or branched alkyl group or alkenyl group having 2 to 10 carbon atoms, and some of the -CH ₂ - groups in the alkyl group or alkenyl group may be substituted with -O- groups. Furthermore, some of the hydrogen atoms in these groups R ₁₂ to R ₁₄ may be substituted with halogen atoms.)

The amount of component (C) is preferably 3 parts by weight or more and 30 parts by weight or less, and more preferably 5 parts by weight or more and 20 parts by weight or less, per 100 parts by weight of the total of components (A) and (B). When the amount of component (C) is 3 parts by weight or less, the sensitivity of the photosensitive resin composition is good and the photopolymerization rate can be sufficiently increased. When the amount of component (C) is 30 parts by weight or less, the sensitivity of the photosensitive resin composition is kept within an appropriate range, making it easy to obtain a cured film having the desired pattern line width and the desired pattern edge shape.

4. Component (D) Component (D) is a light-shielding component that is a black pigment, a mixed-color organic pigment, or a light-shielding material. As component (D), any known light-shielding component can be used without any particular restrictions. In addition, component (D) is preferably dispersed so that the average particle size (average particle size measured with a laser diffraction/scattering particle size distribution meter or a dynamic light scattering particle size distribution meter) is 1 nm or more and 1000 nm or less.

Examples of the black pigments include perylene black, cyanine black, aniline black, lactam black, carbon black, and titanium black.

Examples of the above mixed-color organic pigments include pigments in which at least two colors of organic pigments such as azo pigments, condensed azo pigments, azomethine pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, isoindoline pigments, dioxazine pigments, threne pigments, perylene pigments, perinone pigments, quinophthalone pigments, diketopyrrolopyrrole pigments, and thioindigo pigments are mixed.

Component (D) may be used alone or in combination of two or more types depending on the desired function of the photosensitive resin composition.

In addition, examples of organic pigments that can be used when a mixed-color organic pigment is used as component (D) include, but are not limited to, those having the following Color Index names:
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 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 60, 80, etc. Pigment Violet 19, 23, 37, etc.

The amount of the (D) component can be determined arbitrarily depending on the desired light-shielding degree, but is preferably 20% by mass or more and 80% by mass or less, and more preferably 40% by mass or more and 70% by mass or less, based on the total mass of the solid content in the photosensitive resin composition. When an organic pigment such as aniline black, cyanine black, lactam black, or a carbon-based light-shielding component such as carbon black is used as the light-shielding component of the (D) component, the amount of the (D) component is preferably 40% by mass or more and 60% by mass or less based on the solid content in the photosensitive resin composition. When the amount of the light-shielding component is 20% by mass or more based on the solid content in the photosensitive resin composition, the light-shielding property of the cured film can be sufficiently increased. When the amount of the light-shielding component is 80% by mass or less based on the solid content in the photosensitive resin composition, the content of the photosensitive resin that is the original binder can be sufficiently increased to obtain the desired development characteristics and film-forming ability.

The above-mentioned (D) component is usually mixed with other formulation components as a light-shielding component dispersion dispersed in a solvent, and a dispersant can be added in this case. The dispersant can be any known compound (compounds commercially available under the names of dispersant, dispersion wetting agent, dispersion promoter, etc.) used for dispersing pigments (light-shielding components) without any particular restrictions.

Examples of dispersants for the light-shielding components include cationic polymer dispersants, anionic polymer dispersants, nonionic polymer dispersants, pigment derivative dispersants (dispersing aids), and the like. In particular, the dispersant is preferably a cationic polymer dispersant having a cationic functional group such as an imidazolyl group, a pyrrolyl group, a pyridyl group, or a primary, secondary, or tertiary amino group as an adsorption point to the colorant, an amine value of 1 mgKOH/g to 100 mgKOH/g, and a number average molecular weight (Mn) of 1,000 to 100,000. The blending amount of the dispersant for the light-shielding component is preferably 1% by mass to 35% by mass, and more preferably 2% by mass to 25% by mass, based on the total mass of the light-shielding component. In addition, high-viscosity substances such as resins generally have the effect of stabilizing dispersion, but those that do not have the ability to promote dispersion are not treated as dispersants. However, there is no restriction on using them for the purpose of stabilizing dispersion.

5. Component (E) Component (E) is silica particles. The method for producing the silica particles, such as a gas phase reaction or a liquid phase reaction, and the shape (spherical, non-spherical) are not particularly limited.

The type of silica particles used as component (E) in the present invention is not particularly limited. Solid silica or hollow silica particles may be used. Note that "hollow silica particles" refer to silica particles that have a cavity inside the particle.

Component (E) can lower the refractive index of the cured film (light-shielding film). As a result, reflection caused by the difference in refractive index between the transparent substrate, air, transparent protective film, etc. and the cured film (light-shielding film) can be suppressed, thereby lowering the reflectance of the cured film.

The average particle size of the (E) component is preferably 1 nm or more and 100 nm or less, and more preferably 10 nm or more and 90 nm or less. Compared with silica particles with a small average particle size of a few nm, silica particles having a size within the above range are considered to be less likely to cause aggregation between particles. Therefore, when the particle size of the (E) component is within the above range, the dispersion stability of the (E) component is improved, the movement of the (E) component due to aggregation in the light-shielding film is less likely to be restricted, and a sufficient amount of the (E) component can be unevenly distributed on the film surface side, so that the reflectance on the film surface side can be more sufficiently reduced. In addition, by making the average particle size of the (E) component 100 nm or less, the (E) component can be moved to a certain degree in the coating film to make it easier to unevenly distribute the (E) component on the film surface side, and the decrease in linearity and surface smoothness of the cured film due to the (E) component unevenly distributed on the film surface side can be suppressed.

The average particle size of component (E) can be measured by the cumulant method using a dynamic light scattering particle size distribution analyzer "Particle Size Analyzer FPAR-1000" (manufactured by Otsuka Electronics Co., Ltd.).

The refractive index of component (E) is preferably 1.10 or more and 1.47 or less. In addition to being able to use the refractive index of ordinary silica particles (1.45 to 1.47), it is also possible to use hollow silica particles with a low refractive index, thereby making the refractive index of the light-shielding film lower than the refractive index of a light-shielding film containing only ordinary silica particles.

The refractive index of component (E) can be determined from a transparent mixture obtained by mixing the above-mentioned silica particles processed into a powder with a standard refractive index liquid of known refractive index. The refractive index of the above-mentioned silica particles can be measured using an Abbe refractometer.

The shape of component (E) may be spherical or elliptical. Of these, spherical is preferred.

The sphericity of component (E) is preferably 1.0 or more and 1.5 or less. If the sphericity of the silica particles is within this range, the particle shape will be close to a perfect sphere. This allows the silica particles to be uniformly packed in the in-plane direction (direction horizontal to the substrate surface) in a thin light-shielding film, and a light-shielding film can be formed in which the silica particles are not exposed to the outside from the surface of the cured film while maintaining the smoothness of the surface of the cured film. This makes it possible to obtain a light-shielding film with a low refractive index and sufficient strength.

The sphericity of component (E) can be determined from the ratio of the longest diameter to the shortest diameter of the particle (the average value of any 100 silica particles). Here, the longest diameter and the shortest diameter of component (E) are values determined by photographing component (E) with a transmission electron microscope and measuring the longest diameter and the shortest diameter of component (E) from the micrograph obtained.

Component (E) can be mixed with other ingredients as a dispersion in a solvent using component (F) (dispersant) described below.

The amount of component (E) is preferably 0.1% by mass or more and 5% by mass or less, and more preferably 0.1% by mass or more and 2% by mass or less, based on the total mass of the photosensitive resin composition including the solvent. When the amount of silica particles is within the above range, it is possible to achieve low reflectance while ensuring good photopatterning properties.

The ratio (mE/mD) of the total mass (mE) of the (E) silica particles to the total mass (mD) of the (D) light-shielding component is preferably 0.01 or more and 0.20 or less, and more preferably 0.05 or more and 0.10 or less. When the ratio of the total mass (mE) of the (E) silica particles to the total mass (mD) of the (D) light-shielding component is in the above range, it is possible to achieve both high light-shielding properties and low reflectance.

6. (F) component The (F) component is a dispersant. In this embodiment, the (F) component has an acid value and an amine value, and the acid value and the amine value are both 10 mgKOH/g or more and 80 mgKOH/g or less. When the amine value of the (F) component is 10 mgKOH/g or more, the dispersibility of the silica particles can be increased. On the other hand, a dispersant having only an amine value increases the dispersibility of the silica particles, but reduces the solubility of the silica particles in the developer, so that the silica particles remain as residues at the pattern edge portion and reduce linearity. On the other hand, when the amine value of the dispersant is 10 mgKOH/g or more and the acid value is also 10 mgKOH/g or more, it is possible to form a high-definition pattern while increasing the dispersibility of the silica particles. On the other hand, by setting both the acid value and the amine value to 80 mgKOH/g or less, the solubility of the silica particles protected by the dispersant in the developer is not excessively increased, and the reduction in the definition of the pattern formed can be suppressed. From the above viewpoints, it is preferable that either the amine value or the acid value of the dispersant is 30 mgKOH/g or more and 80 mgKOH/g or less, and it is more preferable that both are 30 mgKOH/g or more and 80 mgKOH/g or less.

The acid value of component (F) means the number of milligrams of KOH required to neutralize 1 g of the resin component (solid content), and can be measured in accordance with JIS K 0070 (1992). The amine value of the dispersant, which is component (F), means the number of milligrams of KOH equivalent to the amount of acid (acetic acid, etc.) required to neutralize 1 g of the resin component (solid content), and can be measured in accordance with JIS K 7237 (1995).

Examples of component (F) include alkylammonium salts and alkylolammonium salts of acidic polymers, alkylammonium salts and alkylolammonium salts of polymeric copolymers having acid groups, neutralized salts of polymers having alkylamino groups, and phosphate salts of polymeric copolymers. Of these, polymeric compounds having an alkylammonium salt structure are preferred, and alkylammonium salts of acidic polymers and alkylammonium salts of polymeric copolymers having acid groups are more preferred. By using a polymeric compound having an alkylammonium salt structure as a dispersant, the generation of aggregated foreign matter derived from silica particles can be more significantly suppressed.

Examples of commercially available products of component (F) include DISPERBYK-140, 142, 145, 2001, 2025, and 9076 (all manufactured by BYK Japan, "DISPERBYK" is a registered trademark of the company). Of the above commercially available products, DISPERBYK-140, 142, and 9076 are preferred, with DISPERBYK-140 and 9076 being more preferred.

The amount of the dispersant (F) is preferably 0.01% by mass or more and 0.5% by mass or less based on the total mass of the photosensitive resin composition including the solvent.

The ratio (mF/mE) of the total mass (mF) of the (F) component to the total mass (mE) of the (E) component is preferably 0.02 or more and 0.6 or less, and more preferably 0.03 or more and 0.4 or less. When the ratio of the total mass (mF) of the (F) component to the total mass (mE) of the (E) component is in the above range, the reflectance of the glass substrate side and the film surface side is reduced, while the dispersibility of the silica particles is improved, and the generation of aggregated foreign matter derived from the silica particles can be suppressed.

7. Component (G) The component (G) is a solvent. In the present embodiment, the photosensitive resin composition contains, as the component (G), at least a first solvent which is propylene glycol monomethyl ether, and a second solvent having a vapor pressure of less than 250 Pa at 20° C. (the second solvent excludes the solvent represented by the following general formula (1)).
RO-(CH ₂ CH ₂ O)n-R... (1)
In formula (1), R independently represents an alkyl group or an aryl group which may have a substituent, and n is an integer of 2 or more and 5 or less.

The second solvent, which has a low vapor pressure at 20°C and is difficult to evaporate, slows down the drying speed of the coating film formed by applying the photosensitive resin composition to a substrate or the like when the coating film is dried before pre-baking. According to the inventor's new findings, as the amount of solvent in the coating film decreases from the surface side of the coating film during this drying, the (E) component moves to the bottom side (substrate side) of the coating film where a large amount of solvent remains. Therefore, the cured film formed by subsequent curing is likely to have a small amount of (E) component on the film surface side. In contrast, by using a second solvent that is difficult to evaporate, the solvent is likely to remain on the surface side of the coating film for a long time during drying, suppressing the movement of the (E) component to the bottom side (substrate side) of the coating film, and the (E) component can be moved to the film surface side as the solvent evaporates, so that the (E) component is unevenly distributed on the film surface side. As a result, the cured film formed by subsequent curing has a sufficient amount of (E) component on the film surface side, so that the refractive index on the film surface side is adjusted and the reflectance on the film surface side is also reduced. From the above viewpoints, it is more preferable that the vapor pressure of the second solvent at 20°C is greater than 1 Pa and less than 100 Pa, and even more preferable that it is greater than 10 Pa and less than 50 Pa.

In addition, in this embodiment, an appropriate amount of the dispersant that does not easily cause silica aggregation is used as the (F) component, so that the movement of the (E) component is less likely to be restricted by aggregation, and a sufficient amount of the (E) component can be unevenly distributed on the film surface side, which is thought to make it possible to more sufficiently reduce the reflectance on the film surface side.

However, according to further findings by the inventors, such an effect cannot be confirmed for the solvent represented by general formula (1), and therefore the solvent represented by general formula (1) is not included in the second solvent. However, there is no particular disadvantage in using the solvent represented by general formula (1) as the third solvent or other solvent.

Examples of the second solvent include methoxybutyl acetate, ethyl 3-ethoxypropionate, 3-methoxy-3-methyl-1-butyl acetate, dipropylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol, and propylene glycol diacetate, ethylene glycol, propylene glycol, methyl carbitol, ethyl carbitol, butyl carbitol, butyl cellosolve acetate, carbitol acetate, ethyl carbitol acetate, butyl carbitol acetate, propylene glycol monoethyl ether acetate, etc. Of these, 3-methoxy-3-methyl-1-butyl acetate, 3-methoxy-3-methyl-1-butanol, and propylene glycol diacetate are preferred.

The (G) component preferably contains a third solvent having a relative dielectric constant of 10.0 or more and 30.0 or less at 23°C. The third solvent can stabilize the silanol groups on the surface of the silica particles by solvation, and suppress the aggregation of the (E) component in the photosensitive resin composition. From the above viewpoint, the relative dielectric constant of the third solvent at 23°C is preferably 13.0 or more and 20.0 or less, and more preferably 13.0 or more and 18.0 or less. The photosensitive resin composition may contain a 3-1 solvent having a relative dielectric constant in the above range in addition to the second solvent, or the second solvent may contain a 3-2 solvent that satisfies the above requirement for the relative dielectric constant, or may contain both the 3-1 solvent and the 3-2 solvent. The 3-2 solvent is a solvent that is contained in both the second solvent and the third solvent.

From the viewpoint of appropriately adjusting the dielectric constant of the entire (G) component and enhancing the aggregation suppression effect of the (E) component, it is preferable that the (G) component contains the 3-1 solvent, or that the second solvent contains a solvent having a dielectric constant of less than 10.0 at 23°C and a 3-2 solvent having a dielectric constant of 10.0 or more and 30.0 or less at 23°C. Among these, it is more preferable that the (G) component contains the 3-1 solvent, from the viewpoint of being able to adjust the vacuum drying time within an appropriate range and being able to prevent film formation defects caused by remaining solvent due to insufficient vacuum drying.

The third solvent is preferably a saturated ketone having a linear, branched or cyclic structure with 3 to 12 carbon atoms, or an unsaturated alcohol having a linear, branched or cyclic structure with 3 to 12 carbon atoms.

Examples of the saturated ketones as the third solvent include acetone, methyl ethyl ketone, cyclopentanone, and cyclohexanone. Examples of the saturated alcohols as the third solvent include ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol, 1-methoxy-2-propanol, ethyl lactate, and 3-methoxy-3-methyl-1-butanol. Other examples of the third solvent include glycol ethers such as methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether. Of these, cyclohexanone, ethyl lactate, 1-methoxy-2-propanol, 3-methoxy-3-methyl-1-butanol, and propylene glycol monoethyl ether are preferred, and cyclohexanone, ethyl lactate, and 3-methoxy-3-methyl-1-butanol are more preferred.

The amount of the first solvent is preferably 10% by mass or more and 80% by mass or less, more preferably 20% by mass or more and 70% by mass or less, even more preferably 30% by mass or more and 70% by mass or less, and most preferably 45% by mass or more and 70% by mass or less, based on the total mass of the (G) component. By increasing the amount of the first solvent, the solubility of the (A) component and the (B) component and the dispersibility of the (D) component can be further improved.

The amount of the second solvent is preferably 10% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 45% by mass or less, even more preferably 10% by mass or more and 40% by mass or less, and most preferably 10% by mass or more and 35% by mass or less, based on the total mass of the (G) component. By increasing the amount of the second solvent, more of the (E) component is present on the film surface side of the cured film, and the reflectance of the film surface side of the cured film can be sufficiently reduced. By appropriately suppressing the amount of the second solvent, the vacuum drying time can be adjusted to an appropriate range. In addition, it is possible to prevent film formation defects caused by residual solvent due to insufficient vacuum drying. The amount of the second solvent was calculated including the content of the 3-2 solvent.

The amount of the third solvent is preferably 10% by mass or more and 50% by mass or less, more preferably 15% by mass or more and 50% by mass or less, even more preferably 15% by mass or more and 40% by mass or less, and most preferably 15% by mass or more and 25% by mass or less, based on the total mass of the (G) component. By increasing the amount of the third solvent, it is possible to suppress the aggregation of the (E) component and to reduce the reflectance more efficiently. By appropriately suppressing the amount of the third solvent, it is possible to further improve the coatability of the photosensitive resin composition. The amount of the third solvent is the sum of the content of the 3-1 solvent and the content of the 3-2 solvent.

When the (G) component contains the 3-1 solvent as the third solvent, the blending amount of the 3-1 solvent is preferably 10% by mass or more and 50% by mass or less, more preferably 15% by mass or more and 50% by mass or less, even more preferably 15% by mass or more and 40% by mass or less, and most preferably 15% by mass or more and 25% by mass or less, based on the total mass of the (G) component. By increasing the amount of the 3-1 solvent, it is possible to suppress the aggregation of the (E) component and more efficiently reduce the reflectance, while adjusting the vacuum drying time to an appropriate range, and it is possible to make it difficult for film formation defects caused by residual solvent due to insufficient vacuum drying to occur. By appropriately suppressing the amount of the 3-1 solvent, it is possible to further improve the coatability of the photosensitive resin composition.

The amount of component (G) is preferably 40% by mass or more and 90% by mass or less, more preferably 60% by mass or more and 90% by mass or less, and even more preferably 80% by mass or more and 90% by mass or less, based on the total mass of the photosensitive resin composition.

8. Other Components The photosensitive resin composition may contain additives such as a resin other than component (A), such as an epoxy resin, a curing agent, a curing accelerator, a thermal polymerization inhibitor and an antioxidant, a plasticizer, a filler other than silica, a leveling agent, an antifoaming agent, a surfactant, and a coupling agent, as necessary.

Examples of thermal polymerization inhibitors and antioxidants include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine, hindered phenol compounds, etc. Examples of plasticizers include dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, etc. Examples of fillers include glass fiber, mica, alumina, etc. Examples of defoamers and leveling agents include silicone-based, fluorine-based, and acrylic compounds. Examples of surfactants include fluorine-based surfactants, silicone-based surfactants, etc. Examples of coupling agents include 3-(glycidyloxy)propyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, etc.

9. Preparation of Photosensitive Resin Composition The photosensitive resin composition can be prepared by mixing and dispersing the above-mentioned components (A) to (G) and, optionally, other components. For example, a light-shielding component dispersion containing the components (A), (B), (C), and (D) and a silica particle dispersion containing the components (E) and (F) can be mixed to obtain a photosensitive resin composition.

By incorporating the dispersant (F) into the silica particle dispersion (E) in advance, it is possible to improve the dispersion stability of the silica dispersion and prevent the generation of aggregates when it is mixed with other resin components.

10. Light-shielding film The photosensitive resin composition can be used to produce a light-shielding film by applying it to a substrate or the like, drying the solvent, and curing it by irradiating it with light (including ultraviolet light, radiation, etc.). At this time, a light-shielding film having a desired pattern shape can also be obtained by providing areas that are exposed to light and areas that are not exposed to light using a photomask or the like, curing only the areas that are exposed to light, and dissolving the other areas with an alkaline solution.

Specifically, the photosensitive resin composition can be applied to a substrate by known methods such as immersion in a solution, spraying, or methods using a roller coater, land coater, slit coater, or spinner. After applying the composition to the desired thickness using these methods, the composition is dried and then the solvent is removed (prebaked) to form a coating film.

Drying can be performed by a method such as vacuum drying under conditions such that the ultimate pressure is 10 to 1000 Pa in 10 to 180 seconds. Alternatively, degassing can be performed all at once until the desired ultimate pressure is reached, or the pressure can be reduced stepwise to prevent film defects such as bumping.

Pre-baking is performed by heating in an oven or on a hot plate, vacuum drying, or a combination of these. The heating temperature and heating time in pre-baking can be appropriately selected depending on the solvent used, but it is preferable to perform pre-baking at 80 to 120°C for 1 to 10 minutes, for example.

Radiation used for exposure can be, for example, visible light, ultraviolet light, far ultraviolet light, electron beams, X-rays, etc., but the wavelength range of the radiation is preferably 250 to 450 nm. In addition, as a developer suitable for this alkaline development, for example, an aqueous solution of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, tetramethylammonium hydroxide, etc. can be used. These developers can be appropriately selected according to the characteristics of the resin layer, but it is also effective to add a surfactant as necessary. The development temperature is preferably 20 to 35°C, and fine images can be precisely formed using a commercially available developing machine, ultrasonic cleaner, etc. Note that after alkaline development, the film is usually washed with water. As a development processing method, a shower development method, a spray development method, a dip (immersion) development method, a puddle (liquid puddle) development method, etc. can be applied.

After development in this manner, a heat treatment (post-baking) may be performed at 70 to 250°C for 20 to 100 minutes to improve the adhesion between the light-shielding film and the substrate. Post-baking can be performed by heating in an oven, a hot plate, etc., in the same manner as pre-baking.

The light-shielding film thus obtained can be used as a black resist in a display device. For example, the light-shielding film can be used as a black matrix, black column spacer, frame, etc. in a color filter or touch panel.

For example, a color filter having the above-mentioned light-shielding film as a black matrix is produced by forming a light-shielding film having a thickness of 1.0 to 2.0 μm on a transparent substrate, and then forming red, blue, and green pixels by photolithography after forming the light-shielding film, or by injecting red, blue, and green inks into the light-shielding film by an inkjet process.

When the light-shielding film is to be a black column spacer, a single black resist may be used to create multiple sections with different film thicknesses, with one functioning as a spacer and the other functioning as a black matrix.

The method for producing a light-shielding film having a pattern shape is not limited to photolithography, which involves exposure to light and alkaline development, and the pattern may be formed by screen printing or the like.

The light-shielding film is formed by applying a photosensitive resin composition onto a glass substrate, pre-baking the composition on a hot plate at 90° C. for 1 minute, and irradiating the composition with ultraviolet light at 50 mJ/cm ² from an ultra-high pressure mercury lamp with an i-line illuminance of 30 mW/cm ^2. The reflectance of the resulting light-shielding film having a thickness of 1.2 μm is preferably 6% or less, more preferably 5% or less, on the glass surface side, and more preferably 6.5% or less, more preferably 5.5% or less, on the film surface side.

The photosensitive resin composition can be suitably used for the above-mentioned applications, as well as for various other coating materials. In particular, color filter inks used in liquid crystal display devices or imaging devices, and the light-shielding films formed therefrom are useful as color filters, black matrices for liquid crystal projection, and the like. In addition to color filter inks for color liquid crystal displays, the photosensitive resin composition can also be used as ink materials for color separation or light-shielding in various multi-color display devices, such as organic electroluminescent devices typified by organic EL elements, color liquid crystal display devices, color facsimiles, and image sensors.

In particular, the light-shielding film can reduce the reflectance on the film surface side, so when used in applications where the film surface of a liquid crystal display or the like is placed inside a display device, it can suppress the loss of light from an internal light source due to reflection inside the device. Also, when used in applications where the film surface of an organic LED (OLED) or the like is placed outside a display device, it can improve the contrast in bright areas by reducing the reflection of external light, and improve the light extraction efficiency from the light-emitting side to improve the luminous efficiency.

Hereinafter, the embodiments of the present invention will be described in detail based on examples and comparative examples, but the present invention is not limited to these. In addition, in the present invention, when the first decimal place of the content of each component is 0, the notation after the decimal point may be omitted.

First, we will explain the synthesis examples of the unsaturated group-containing alkali-soluble resin, which is component (A). Unless otherwise specified, the resins in these synthesis examples were evaluated as follows.

[Solid content]
1 g of the resin solution obtained in Synthesis Example was impregnated into a glass filter (weight: _W0 (g)), weighed ( _W1 (g)), and the weight after heating at 160°C for 2 hours ( _W2 (g)) was calculated from the following formula.
Solid content (wt%)=100×(W ₂ −W ₀ )/(W ₁ −W ₀ )

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

[Molecular weight]
Measurement was performed using gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation, solvent: tetrahydrofuran, columns: TSKgelSuperH-2000 (2 columns) + TSKgelSuperH-3000 (1 column) + TSKgelSuperH-4000 (1 column) + TSKgelSuperH-5000 (1 column) (manufactured by Tosoh Corporation), temperature: 40°C, speed: 0.6 ml/min), and the weight average molecular weight (Mw) was calculated as a value converted into standard polystyrene (manufactured by Tosoh Corporation, PS-oligomer kit).

[Average particle size]
The average particle size of the silica particles was determined by the cumulant method using a dynamic light scattering particle size distribution analyzer "Particle Size Analyzer FPAR-1000" (manufactured by Otsuka Electronics Co., Ltd.).

The abbreviations used in the synthesis examples are as follows.
BPFE: Bisphenolfluorene type epoxy compound (a reaction product of 9,9-bis(4-hydroxyphenyl)fluorene and chloromethyloxirane. In the compound of general formula (2), X is a fluorene-9,9-diyl group, and R ₁ to R ₄ are hydrogen.)
AA: Acrylic acid BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride THPA: Tetrahydrophthalic anhydride TEAB: Tetraethylammonium bromide PGMEA: Propylene glycol monomethyl ether acetate

[Synthesis Example]
BPFE (114.4g, 0.23 mol), AA (33.2g, 0.46 mol), PGMEA (157g) and TEAB (0.48g) were charged into a 500ml four-neck flask equipped with a reflux condenser, and the mixture was stirred at 100 to 105 ° C for 20 hours to react. Next, BPDA (35.3g, 0.12 mol) and THPA (18.3g, 0.12 mol) were charged into the flask, and the mixture was stirred at 120 to 125 ° C for 6 hours to obtain an unsaturated group-containing alkali-soluble resin (A). The solid content concentration of the obtained resin solution was 56.0 mass%, the acid value (solid content equivalent) was 103 mg KOH / g, and the Mw by GPC analysis was 3600.

The photosensitive resin compositions of Examples 1 to 11 and Comparative Examples 1 to 12 were prepared in the amounts (units: parts by mass) shown in Tables 1 to 4. The ingredients used in Tables 1 to 4 are as follows:

(Alkali-soluble resin containing unsaturated groups)
(A): Unsaturated group-containing alkali-soluble resin solution (solid content concentration: 56.0% by mass) obtained in the above Synthesis Example

(Photopolymerizable Compound)
(B): A mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (Aronix M-405, manufactured by Toagosei Co., Ltd., "Aronix" is a registered trademark of the company)

(Photopolymerization initiator)
(C)-1: Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetyloxime) (Irgacure OXE-02, manufactured by BASF Japan, "Irgacure" is a registered trademark of the company)
(C)-2: ADEKA ARCLES NCI-831, manufactured by ADEKA Corporation, "ADEKA ARCLES" is a registered trademark of the company.

(Carbon Black Dispersion)
(D): Carbon black concentration 25.0% by mass, polymer dispersant concentration 2.0% by mass, dispersion resin (alkali-soluble resin (A) of Synthesis Example (solid content 8.0% by mass)) in PGMEA (solid content 35.0% by mass)

(E): PGMEA dispersion of silica particles "YA050C" (manufactured by Admatechs Co., Ltd., solid content concentration 30% by mass, average particle size 50 nm)

(Dispersant)
(F)-1: DISPERBYK-140 (propylene glycol monomethyl ether acetate dispersion having a solid content of 52% by mass, acid value of 73 mg KOH/g, amine value of 76 mg KOH/g)
(F)-2: DISPERBYK-142 (propylene glycol monomethyl ether acetate dispersion having a solid content of 60% by mass, acid value of 46 mg KOH/g, amine value of 43 mg KOH/g)
(F)-3: DISPERBYK-9076 (solid content concentration 100 mass%, acid value 38 mg KOH/g, amine value 44 mg KOH/g)
(F)-1 to (F)-3 are all manufactured by BYK Japan, and "DISPERBYK" is a registered trademark of the same company.

Furthermore, (F)-1 is a dispersant having an alkyl ammonium salt structure of an acidic polymer, (F)-2 is a phosphate ester salt type dispersant of a polymer copolymer, and (F)-3 is a dispersant having an alkyl ammonium salt structure of a polymer copolymer having an acid group.

(solvent)
(G)-1: Propylene glycol monomethyl ether acetate (PGMEA)
(G)-2: Ethyl lactate (EL)
(G)-3: Methoxybutyl acetate (MBA)
(G)-4: 3-ethoxyethyl propionate (EEP)
(G)-5: 3-methoxy-3-methyl-1-butanol (MMB)
(G)-6: 3-methoxy-3-methyl-1-butyl acetate (MMBA)
(G)-7: Propylene glycol diacetate (PDGA)
(G)-8: 1-methoxy-2-propanol (MMPG)
(G)-9: methyl 3-methoxypropionate (MMP)
(G)-10: Cyclohexanone (ANON)
(G)-11: Diethylene glycol dimethyl ether (MDM)
(G)-12: Diethylene glycol diethyl ether (EDE)
(G)-13: Diethylene glycol ethyl methyl ether (EDM)
(G)-14: Diethylene glycol dibutyl ether (BDB)

In Tables 1 to 4, the vapor pressure of each solvent at 20°C and the relative dielectric constant at 23°C are shown in parentheses.

[evaluation]
A light-shielding film for use in evaluation was prepared by curing a photosensitive resin composition for black resist as follows.

(Preparation of light-shielding film for evaluation)
The photosensitive resin composition shown in Table 1 was applied to a 125 mm x 125 mm glass substrate "#1737" (manufactured by Corning) (hereinafter referred to as "glass substrate"), the surface of which had been cleaned by irradiating it with ultraviolet light having a wavelength of 254 nm and an illuminance of 1000 mJ/cm ² in advance using a low-pressure mercury lamp, using a spin coater so that the film thickness after heat curing treatment would be 1.2 μm, and the pressure was reduced to 50 Pa in 45 seconds using a vacuum dryer at 23 ° C. to evaporate the solvent, and then the substrate was pre-baked at 90 ° C. for 1 minute using a hot plate to prepare a light-shielding film. Next, the exposure gap was adjusted to 100 μm, and a negative photomask with a line/space of 10 μm/50 μm was placed on the dried light-shielding film, and ultraviolet light of 50 mJ/cm ² was irradiated using an ultra-high pressure mercury lamp with an i-line illuminance of 30 mW/cm ² to perform a photocuring reaction of the photosensitive portion.

Next, the exposed light-shielding film was subjected to a development process at 25° C. with a 0.04% potassium hydroxide solution at a shower pressure of 1 kgf/cm ² for +10 seconds and +20 seconds from the development time at which a pattern begins to appear (break time = BT), and then washed with water sprayed at 5 kgf/cm ² to remove the unexposed parts of the light-shielding film to form a light-shielding film pattern on a glass substrate, and main curing (post-baking) was performed at 230° C. for 30 minutes using a hot air dryer to obtain light-shielding films for evaluation according to Examples 1 to 10 and Comparative Examples 1 to 7.

The light-shielding films prepared for evaluation above were evaluated for the following items.

[Reflectance evaluation (substrate side, film surface side)]
(Evaluation method)
The reflectance of the substrate (glass substrate) side and the film surface side of the light-shielding film-attached substrate prepared in the same manner as the light-shielding film for evaluation was measured at an incident angle of 2° using an ultraviolet-visible-infrared spectrophotometer "UH4150" (manufactured by Hitachi High-Tech Science Co., Ltd.).

(Evaluation criteria (substrate side))
A: The reflectance is 5% or less. B: The reflectance is more than 5% and less than 6%. C: The reflectance is 6% or more.

(Evaluation criteria (film surface side))
◯: The reflectance is 5.5% or less. Δ: The reflectance is more than 5.5% and 6.5% or less. ×: The reflectance is more than 6.5%.

[Optical Density Evaluation]
(Evaluation method)
The optical density (OD) of the prepared light-shielding film for evaluation was determined using a Macbeth transmission densitometer. The film thickness of the light-shielding film formed on the substrate was also measured, and the optical density (OD) value was divided by the film thickness to obtain OD/μm.

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

[Evaluation of agglomerated foreign matter]
(Evaluation method)
The light-shielding film for evaluation after the main curing (post-baking) was observed using an optical microscope to check for the presence or absence of aggregated foreign matter.

(Evaluation criteria)
◯: No agglomerated foreign matter was found on the light-shielding film △: Agglomerated foreign matter was found on a part of the light-shielding film ×: Agglomerated foreign matter was found on the entire surface of the light-shielding film

The above evaluation results are shown in Tables 5 to 7.

As shown in Tables 5 to 7, by using a dispersant with an acid value and an amine value both of which are 10 mgKOH/g or more and 80 mgKOH/g or less, and by using a first solvent that is propylene glycol monomethyl ether acetate as the solvent, and a second solvent (excluding the solvent represented by general formula (1)) with a vapor pressure of less than 250 Pa at 20°C, it was possible to reduce the reflectance not only on the glass substrate side but also on the film surface side.

The photosensitive resin composition of the present invention can provide a photosensitive resin composition for black matrices that combines high light-shielding properties with low reflectance, and a light-shielding film, color filter, and touch panel using the same. In addition, the color filter and touch panel can provide various display devices with excellent visibility.

Claims (16)

(A) an unsaturated group-containing photosensitive resin;
(B) a photopolymerizable compound having at least two unsaturated bonds;
(C) a photopolymerization initiator;
(D) at least one light-shielding component selected from the group consisting of black pigments, mixed color pigments, and light-shielding materials;
(E) silica particles;
(F) a dispersant; and
(G) a solvent,
The dispersant (F) has an acid value and an amine value, and both of the acid value and the amine value are 10 mgKOH/g or more and 80 mgKOH/g or less,
a ratio (mF/mE) of the total mass (mF) of the dispersant (F) to the total mass (mE) of the silica particles (E) is 0.02 or more and 0.60 or less;
The (G) solvent includes a first solvent which is propylene glycol monomethyl ether acetate, and a second solvent having a vapor pressure of less than 250 Pa at 20° C. (the second solvent excludes solvents represented by the following general formula (1)).
RO-(CH ₂ CH ₂ O)n-R... (1)
(In general formula (1), R independently represents an alkyl group or an aryl group which may have a substituent, and n is an integer of 2 or more and 5 or less.)
Photosensitive resin composition for black resist. 2. The photosensitive resin composition for black resist according to claim 1, wherein the unsaturated group-containing photosensitive resin (A) is an unsaturated group-containing photosensitive resin obtained by reacting a reaction product of an epoxy compound having two glycidyl ether groups derived from a bisphenol represented by the following general formula (2) with (meth)acrylic acid, and further reacting the reaction product with a polybasic carboxylic acid or an anhydride thereof:

(In general formula (2), R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogen atom; X represents -CO-, -SO ₂ -, -C(CF ₃ ) ₂ -, -Si(CH ₃ ) ₂ -, -CH ₂ -, -C(CH ₃ ) ₂ -, -O-, a fluorene-9,9-diyl group represented by general formula (3) or a single bond; and l represents an integer of 0 to 10.)

The photosensitive resin composition for black resist according to claim 1, wherein the dispersant (F) is a polymeric compound having an alkyl ammonium salt structure. The (G) solvent is
A third-1 solvent (excluding the second solvent) having a dielectric constant of 10.0 or more and 30.0 or less at 23° C. is included, or
The second solvent includes a solvent having a relative dielectric constant of less than 10.0 at 23° C. and a third-2 solvent having a relative dielectric constant of 10.0 or more and 30.0 or less at 23° C.;
The photosensitive resin composition for black resist according to claim 1 . The (G) solvent includes the 3-1 solvent.
The photosensitive resin composition for black resist according to claim 4. The photosensitive resin composition for black resist according to claim 1, wherein the average particle size of the silica particles (E) is 1 nm or more and 100 nm or less. The photosensitive resin composition for black resist according to claim 1, wherein the ratio (mE/mD) of the total mass (mE) of the silica particles (E) to the total mass (mD) of the light-shielding component (D) is 0.01 or more and 0.20 or less. The photosensitive resin composition for black resist according to claim 1, wherein the second solvent is a solvent having a vapor pressure of less than 100 Pa at 20°C. The photosensitive resin composition for black resist according to claim 1, wherein the second solvent contains at least one solvent selected from the group consisting of 3-methoxy-3-methyl-1-butyl acetate, 3-methoxy-3-methyl-1-butanol, and propylene glycol diacetate. The photosensitive resin composition for black resist according to claim 1, which can obtain a light-shielding film having a reflectance of 6.5% or less on the film surface side by curing the photosensitive resin composition for black resist. The photosensitive resin composition for black resist according to claim 1, which can obtain a light-shielding film having a reflectance of 5.5% or less on the film surface side by curing the photosensitive resin composition for black resist. A light-shielding film obtained by curing the photosensitive resin composition for black resist according to any one of claims 1 to 11. A color filter having the light-shielding film according to claim 12 as a black matrix. A touch panel having the light-shielding film according to claim 12. A display device having the color filter according to claim 13. A display device comprising the touch panel according to claim 14.