JP2024107124A - Photosensitive resin composition for black resist, and light-shielding film and color filter obtained by curing the composition - Google Patents

Abstract

[Problem] To provide a photosensitive resin composition for black resist having light-shielding properties and low reflectance, and a light-shielding film and color filter obtained by curing the same. [Solution] The photosensitive resin composition for black resist of the present invention contains (A) an unsaturated group-containing photosensitive resin, (B) a photopolymerizable monomer having at least two ethylenically unsaturated bonds, (C) a photopolymerization initiator, (D) at least one light-shielding component selected from a black pigment, a mixed color pigment, and a light-shielding material, and (E) silica particles. The silica particles, which are component (E), are hollow particles. [Selected Figure] None

Description

The present invention relates to a photosensitive resin composition for black resist and a light-shielding film and color filter obtained by curing the composition.

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

In display devices, etc., in order to suppress light leakage and improve the visibility of the screen of the display device, etc., the concentration of black pigment in the light-shielding film may be increased to increase the light-shielding properties of the light-shielding film (reduce the light transmittance of the light-shielding film). Since the refractive index of the black pigment is higher than that of the transparent substrate and the curable resin, increasing the concentration of black pigment in the light-shielding film increases the reflectance when viewed from the side opposite the surface of the transparent substrate on which the light-shielding film is formed. This increases the reflection at the interface between the light-shielding film formed on the transparent substrate and the transparent substrate, causing problems such as reflections on the light-shielding film and the black matrix boundary being noticeable due to the difference in reflectance with the colored portion of the color filter.

Therefore, there is a demand for a photosensitive resin composition for black resist that has both high light-shielding properties and low reflectance, as well as a light-shielding film and color filter obtained by curing the composition.

For example, Patent Document 1 discloses a black photosensitive resin composition that is characterized by containing hydrophobic silica fine particles and a specific dispersant (urethane-based dispersant). It is said that by using hydrophobic silica fine particles and a specific dispersant, a black matrix that combines high light blocking properties and low reflectance can be formed.

JP 2015-161815 A

However, the inventors' investigations have revealed that the black photosensitive resin composition described in Patent Document 1 was unable to provide a light-shielding film having both high light-shielding properties and low reflectance. In addition, in light-shielding films for sensors in various display devices and solid-state imaging devices, depending on the design of the device configuration, not only is it necessary to reduce the reflectance of the transparent substrate side of the light-shielding film applied to a transparent substrate such as glass, but there are also cases where it is required to reduce the reflectance of the surface opposite to the surface in contact with the transparent substrate (hereinafter referred to as the "coated surface").

The present invention has been made in consideration of these points, and aims to provide a photosensitive resin composition for black resist that has high light-shielding properties and low reflectance, and a light-shielding film and color filter obtained by curing the composition.

The photosensitive resin composition for black resist according to the present invention is a photosensitive resin composition for black resist, which contains (A) an unsaturated group-containing photosensitive resin, (B) a photopolymerizable monomer having at least two ethylenically unsaturated bonds, (C) a photopolymerization initiator, (D) at least one light-shielding component selected from black pigments, mixed color pigments, and light-shielding materials, and (E) silica particles, and the silica particles, which are component (E), are hollow particles.

The light-shielding film according to the present invention is composed of the above-mentioned photosensitive resin composition for black resist.

The color filter according to the present invention has the above-mentioned light-shielding film as a black matrix.

According to the present invention, it is possible to provide a photosensitive resin composition for black resist having high light-shielding properties and low reflectance, and a light-shielding film and a color filter using the same. Furthermore, when the light-shielding film of the present invention is formed on a transparent substrate, it can contribute to realizing low reflectance not only on the transparent substrate side but also on the coated surface side of the light-shielding film.

The present invention will be described in detail below. The photosensitive resin composition for black resist of the present invention (hereinafter, abbreviated as photosensitive resin composition) contains components (A) to (E). Components (A) to (E) will be described below.

(Component (A))
The unsaturated group-containing photosensitive resin, which is the component (A), preferably has a polymerizable unsaturated group and an acidic group for exhibiting alkali solubility in one molecule, and more preferably has both a polymerizable unsaturated group and a carboxy group. The above resin can be widely used without any particular limitation.

An example of the unsaturated group-containing photosensitive resin is an epoxy (meth)acrylate acid adduct obtained by reacting an epoxy compound having two glycidyl ether groups derived from a bisphenol (hereinafter also referred to as a "bisphenol-type epoxy compound represented by general formula (1)") 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.

The unsaturated group-containing photosensitive resin, component (A), is preferably a bisphenol-type epoxy compound represented by general formula (1).

（式（１）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１～５のアルキル基またはハロゲン原子のいずれかであり、Ｘは－ＣＯ－、－ＳＯ_２－、－Ｃ（ＣＦ_３）_２－、－Ｓｉ（ＣＨ_３）_２－、－ＣＨ_２－、－Ｃ（ＣＨ_３）_２－、－Ｏ－、式（２）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、０～１０の整数である。）

(In formula (1), 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 formula (2) or a single bond; and l represents an integer of 0 to 10.)

The bisphenol-type epoxy compound represented by the general formula (1) is an epoxy compound having two glycidyl ether groups obtained by reacting bisphenols with epichlorohydrin. This reaction generally involves oligomerization of the diglycidyl ether compound, and therefore contains 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 acid monoanhydrides of chain hydrocarbon dicarboxylic or tricarboxylic acids include acid monoanhydrides of 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, and diglycolic acid. Furthermore, acid monoanhydrides of dicarboxylic or tricarboxylic acids into which any substituent has been introduced are also included. Examples of monoanhydrides of alicyclic dicarboxylic or tricarboxylic acids include monoanhydrides of cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, norbornanedicarboxylic acid, and the like. Furthermore, monoanhydrides of dicarboxylic or tricarboxylic acids into which an arbitrary substituent has been introduced are also included. Examples of monoanhydrides of aromatic dicarboxylic or tricarboxylic acids include monoanhydrides of phthalic acid, isophthalic acid, trimellitic acid, and the like. Furthermore, monoanhydrides of dicarboxylic or tricarboxylic acids into which an arbitrary substituent has been introduced are also included.

Examples of (a) dicarboxylic or tricarboxylic acid monoanhydrides to be reacted with the hydroxyl group 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 acid monoanhydrides of chain hydrocarbon dicarboxylic or tricarboxylic acids include acid monoanhydrides of 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, and diglycolic acid. Furthermore, acid monoanhydrides of dicarboxylic or tricarboxylic acids to which any substituent has been introduced are also included. Examples of monoanhydrides of alicyclic dicarboxylic or tricarboxylic acids include monoanhydrides of cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, norbornanedicarboxylic acid, and the like. Furthermore, monoanhydrides of dicarboxylic or tricarboxylic acids into which an arbitrary substituent has been introduced are also included. Examples of monoanhydrides of aromatic dicarboxylic or tricarboxylic acids include monoanhydrides of phthalic acid, isophthalic acid, trimellitic acid, and the like. Furthermore, monoanhydrides of dicarboxylic or tricarboxylic acids into which an arbitrary substituent has been introduced are also included.

The molar ratio (a)/(b) of (a) dicarboxylic or tricarboxylic acid anhydride and (b) tetracarboxylic acid dianhydride to be reacted with epoxy (meth)acrylate is preferably 0.01 to 10.0, and more preferably 0.02 or more and less than 3.0. If the molar ratio (a)/(b) deviates from the above range, it is not preferable because the optimal molecular weight for obtaining a photosensitive resin composition with good photopatterning properties cannot 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.

The reaction between the epoxy compound and (meth)acrylic acid, and the reaction between the epoxy (meth)acrylate obtained by this reaction and a polybasic acid or its acid anhydride are not particularly limited, and known methods can be used. The unsaturated group-containing photosensitive resin synthesized by the above reaction preferably has a weight average molecular weight (Mw) of 2,000 to 10,000 and an acid value of 30 to 200 mg/KOH.

Another example of a resin that is preferred as the unsaturated group-containing photosensitive resin, which is 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 a polymerizable unsaturated group-containing alkali-soluble resin 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.

As for the unsaturated group-containing photosensitive resin of component (A), one type may be used alone, or two or more types may be used in combination.

(Component (B))
Examples of the photopolymerizable monomer having at least two ethylenically unsaturated bonds in the 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, and pentaerythritol. The monomers include (meth)acrylic acid esters such as tetra(meth)acrylate, 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, and dendritic polymers having a (meth)acrylic group as compounds having an ethylenic double bond. Only one of these monomers may be used alone, or two or more may be used in combination. In addition, the photopolymerizable monomer having at least two ethylenic unsaturated bonds can play a role of crosslinking the molecules of the contained alkali-soluble resin, and in order to exert this function, it is preferable to use one having three or more photopolymerizable groups. Furthermore, the acrylic equivalent, calculated by dividing the molecular weight of the monomer by the number of (meth)acrylic groups in one molecule, is preferably from 50 to 300, and more preferably from 80 to 200. The component (B) does not have a free carboxy group.

An example of a dendritic polymer having a (meth)acryloyl group as a compound having an ethylenic double bond that can be included in the composition as component (B) is a dendritic polymer obtained by adding a polyvalent mercapto compound to a portion of the carbon-carbon double bonds in the (meth)acryloyl group of a polyfunctional (meth)acrylate. Specifically, it includes a dendritic polymer obtained by reacting a (meth)acryloyl group of a polyfunctional (meth)acrylate represented by general formula (3) with a polyvalent mercapto compound represented by general formula (4).

（式（３）中、Ｒ_５は水素原子またはメチル基であり、Ｒ_６はＲ_７（ＯＨ）_ｋのｋ個のヒドロキシ基の内ｎ個のヒドロキシ基を式中のエステル結合に供与した残り部分である。好ましいＲ_７（ＯＨ）_ｋとしては、炭素数２～８の非芳香族の直鎖または分枝鎖の炭化水素骨格に基づく多価アルコールであるか、当該多価アルコールの複数分子がアルコールの脱水縮合によりエーテル結合を介して連結してなる多価アルコールエーテルであるか、またはこれらの多価アルコールまたは多価アルコールエーテルとヒドロキシ酸とのエステルである。ｋおよびｎは独立に２～２０の整数を表すが、ｋ≧ｎである。）

(In formula (3), R ₅ is a hydrogen atom or a methyl group, and R ₆ is the remaining portion obtained by donating n hydroxy groups out of k hydroxy groups of R ₇ (OH) _k to the ester bond in the formula. Preferred R ₇ (OH) _k is a polyhydric alcohol based on a non-aromatic straight 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 integers of 2 to 20, provided that k≧n.)

（式（４）中、Ｒ_８は単結合または２～６価のＣ１～Ｃ６の炭化水素基であり、ｍはＲ_８が単結合であるときは２であり、Ｒ_８が２～６価の基であるときは２～６の整数である。）

(In formula (4), R ₈ is a single bond or a divalent to hexavalent C1 to C6 hydrocarbon group, and m is 2 when R ₈ is a single bond, and is an integer from 2 to 6 when R ₈ is a divalent to hexavalent group.)

Examples of polyfunctional (meth)acrylates represented by general formula (3) 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 alone or in combination of two or more.

Examples of polyvalent mercapto compounds represented by general formula (4) include trimethylolpropane tri(mercaptoacetate), trimethylolpropane tri(mercaptopropionate), pentaerythritol tetra(mercaptoacetate), pentaerythritol tri(mercaptoacetate), pentaerythritol tetra(mercaptopropionate), dipentaerythritol hexa(mercaptoacetate), dipentaerythritol hexa(mercaptopropionate), etc. These 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.

(Component (C))
Examples of the photopolymerization initiator (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-diphenyl Biimidazole compounds such as biimidazole and 2,4,5-triarylbiimidazole; halomethylthiazole 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; 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, 2-(4-methoxy naphthyl)-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, 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine and the like. Azine 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-one oxime-O- Acetate, 4-ethoxy-2-methylphenyl-9-ethyl-6-nitro-9H-carbazol-3-yl-O-acetyloxime and other O-acyloxime compounds; benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone and other sulfur compounds; 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone and other anthraquinones; azobisisobutyronitrile, benzoyl peroxide, cumene peroxide and other organic peroxides; 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole and other thiol compounds; triethanolamine, triethylamine and other tertiary amines. These photopolymerization initiators may be used alone or in combination of two or more.

In particular, when preparing a photosensitive resin composition containing a colorant, 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 (5) and (6). Among these compounds, when using a colorant at a high pigment concentration or forming a light-shielding film pattern, 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 sensitizers.

（式（５）中、Ｒ_９、Ｒ_１０は、それぞれ独立にＣ１～Ｃ１５のアルキル基、Ｃ６～Ｃ１８のアリール基、Ｃ７～Ｃ２０のアリールアルキル基またはＣ４～Ｃ１２の複素環基を表し、Ｒ_１１はＣ１～Ｃ１５のアルキル基、Ｃ６～Ｃ１８のアリール基、Ｃ７～Ｃ２０のアリールアルキル基を表す。ここで、アルキル基およびアリール基はＣ１～Ｃ１０のアルキル基、Ｃ１～Ｃ１０のアルコキシ基、Ｃ１～Ｃ１０のアルカノイル基、ハロゲンで置換されていてもよく、アルキレン部分は、不飽和結合、エーテル結合、チオエーテル結合、エステル結合を含んでいてもよい。また、アルキル基は直鎖、分岐、または環状のいずれのアルキル基であってもよい。）

(In formula (5), R ₉ and R ₁₀ each independently represent a C1-C15 alkyl group, a C6-C18 aryl group, a C7-C20 arylalkyl group, or a C4-C12 heterocyclic group; and R ₁₁ represents a C1-C15 alkyl group, a C6-C18 aryl group, or a C7-C20 arylalkyl group. Here, the alkyl group and the aryl group may be substituted with a C1-C10 alkyl group, a C1-C10 alkoxy group, a C1-C10 alkanoyl group, or a halogen; the alkylene portion may contain an unsaturated bond, an ether bond, a thioether bond, or an ester bond. The alkyl group may be any of a linear, branched, and cyclic alkyl group.)

（式（６）中、Ｒ_１２およびＲ_１３はそれぞれ独立に、炭素数１～１０の直鎖状もしくは分岐状のアルキル基であるか、炭素数４～１０のシクロアルキル基、シクロアルキルアルキル基もしくはアルキルシクロアルキル基であるか、または炭素数１～６のアルキル基で置換されていてもよいフェニル基である。Ｒ_１４はそれぞれ独立に、炭素数２～１０の直鎖状もしくは分岐状のアルキル基またはアルケニル基であり、当該アルキル基またはアルケニル基中の－ＣＨ_２－基の一部が－Ｏ－基で置換されていてもよい。さらに、これらＲ_１２～Ｒ_１４の基中の水素原子の一部がハロゲン原子で置換されていてもよい。）

(In formula (6), 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 an -O- group. Furthermore, some of the hydrogen atoms in these groups R ₁₂ to R ₁₄ may be substituted with a halogen atom.)

The amount of the photopolymerization initiator (C) used 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 the components (A) and (B). When the blending ratio of component (C) is 3 parts by weight or more, the sensitivity is good and a sufficient photopolymerization speed can be achieved. When the blending ratio of component (C) is 30 parts by weight or less, the sensitivity is adequate, and the desired pattern line width and desired pattern edge can be obtained.

(Component (D))
The light-shielding components such as the black pigment, mixed-color organic pigment, and light-shielding material of the component (D) that can be used in the present invention are not particularly limited, and any known light-shielding components can be used as long as they are dispersed with an average particle size of 1 to 1,000 nm (average particle size measured with a laser diffraction/scattering method particle size distribution meter or a dynamic light scattering method particle size distribution meter).

Examples of black pigments for component (D) include perylene black, cyanine black, aniline black, lactam black, carbon black, and titanium black.

Examples of the mixed-color organic pigment of component (D) include pigments in which at least two colors are mixed, selected from 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.

The above-mentioned (D) component 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 blending ratio of the light-shielding component (D) can be determined arbitrarily depending on the desired light-shielding degree, but is preferably 20 to 80 mass % relative to the solid components in the photosensitive resin composition, and more preferably 40 to 70 mass %. 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, it is particularly preferable that the blending ratio is 40 to 60 mass % relative to the solid components in the photosensitive resin composition. When the light-shielding component is 20 mass % or more relative to the solid components in the photosensitive resin composition, sufficient light-shielding properties can be obtained. When the light-shielding component is 80 mass % or less relative to the solid components in the photosensitive resin composition, the content of the photosensitive resin that is the original binder is not reduced, and the desired development characteristics and film-forming ability can be obtained.

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 include cationic polymer dispersants, anionic polymer dispersants, nonionic polymer dispersants, and pigment derivative dispersants (dispersion aids). 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 to 100 mgKOH/g, and a number average molecular weight (Mn) in the range of 1,000 to 100,000. The blending amount of this dispersant is preferably 1 to 35% by mass, more preferably 2 to 25% by mass, relative to the light-shielding component. Note that 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.

(Component (E))
The silica particles as component (E) are not particularly limited with respect to the production method, such as a gas phase reaction or a liquid phase reaction, and the shape, such as spherical or non-spherical.

The silica particles, which are component (E) used in the present invention, are preferably hollow silica particles. Note that "hollow silica particles" refer to silica particles that have a cavity inside the particle.

Silica particles containing gas within them, such as the silica particles described above, have high dispersibility, and therefore the pattern linearity of the cured film (light-shielding film) obtained by curing the photosensitive resin composition of the present invention is good. In addition, by using silica particles containing gas within them, the refractive index of the light-shielding film containing the silica particles can be reduced.

The average particle size of the silica particles is preferably 40 to 100 nm, and more preferably 50 to 80 nm. When the average particle size is within the above range, the mechanical strength of the silica particles themselves is high, so that the particles are less likely to break even if they are hollow. Furthermore, compared to small particle sizes of a few nm, silica particles within the above range are less likely to aggregate with each other. As a result, within the above particle size range, the silica particles have excellent dispersion stability and can exist uniformly within the light-shielding film. Therefore, variations in reflectance on the light-shielding film are less likely to occur.

Furthermore, within the above range, the proportion of hollow spaces inside the silica particles (hereinafter referred to as porosity) can also be adjusted. Since the refractive index of the silica particles varies depending on the particle size, it is easy to adjust the refractive index of the light-shielding film regardless of the material of the transparent substrate. Note that "porosity" refers to the proportion of hollow spaces within the particle.

The average particle size of the silica particles can be determined by randomly selecting 100 particles, measuring the long and short axis lengths of the particles, and taking the arithmetic average of these. The average particle size of the silica particles 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 the silica particles is preferably 1.10 to 1.41, and more preferably 1.10 to 1.35. By using the silica particles, which have a lower refractive index compared to the refractive index of normal silica particles (1.45 to 1.47), the refractive index of the light-shielding film can be made lower than the refractive index of a light-shielding film containing only normal silica particles.

The refractive index of silica particles can be determined from a transparent mixture obtained by mixing the silica particles processed into a powder with a standard refractive index liquid having a known refractive index. In this case, the refractive index of the standard refractive index liquid of the mixture is taken as the refractive index of the silica particles. The refractive index of the silica particles can be measured using an Abbe refractometer.

The higher the porosity of the silica particles, the lower the refractive index can be, so the porosity of the silica particles is preferably 20% by volume or more, more preferably 20 to 95% by volume, more preferably 25 to 90% by volume, even more preferably 30 to 90% by volume, and particularly preferably 35 to 90% by volume. When the porosity is within the above range, a light-shielding film having a desired refractive index can be easily obtained. In addition, reflection caused by the difference in refractive index between the transparent substrate and the light-shielding film formed can be suppressed, so reflection can be suppressed without providing a separate anti-reflection film or the like on the substrate.

In addition, by setting the porosity of the silica particles within the above range, the weight of the silica particles can be reduced compared to normal silica particles. For this reason, it is believed that the silica particles, unlike normal silica particles, are less likely to settle toward the transparent substrate side even in a photosensitive resin composition and when applied to a transparent substrate. As a result, the silica particles are uniformly dispersed in the light-shielding film, so that not only the reflectance as viewed from the transparent substrate side, but also the reflectance as viewed from the cured film side (light-shielding film surface side) can be reduced.

The porosity of the silica particles can be determined by using a transmission electron microscope. The hollow portion of the silica particle has a low density, and the contrast of the hollow portion is low in a transmission electron microscope photograph, so that the shell portion and the hollow portion of the silica particle can be confirmed. From the microscope photograph, first, the longest diameter and the shortest diameter of the silica particle are measured, and the volume (V ₁ ) is calculated assuming that the particle shape is a perfect sphere with the average value being the particle diameter of the particle. Next, the longest diameter and the shortest diameter of the hollow portion of the particle are measured, and the volume (V ₂ ) is calculated assuming that the hollow portion shape is a perfect sphere with the average value being the diameter of the cavity. The porosity can be expressed as the ratio of the volume (V ₂ ) to the volume (V ₁ ).

As described above, the shape of the silica particles is not particularly limited as long as the particles have the desired porosity. They may be spherical or elliptical. The silica particles used in the present invention are preferably spherical.

The above silica particles preferably have a sphericity of 1.05 to 1.5. 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 into 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 film surface while maintaining the smoothness of the film surface. This makes it possible to obtain a light-shielding film with a low refractive index and sufficient strength.

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

The dispersion liquid used in the photosensitive resin composition of the present invention can be prepared by mixing and dispersing the above components (A) to (E) using an appropriate method.

(solvent)
In addition to the components (A) to (E), the photosensitive resin composition of the present invention preferably contains a solvent as component (F). Examples of the solvent 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. Examples of the acetic acid esters include glycol ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether, and acetates 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 alone or in combination of two or more kinds, a uniform solution-like composition can be obtained.

The photosensitive resin composition of the present invention may also contain additives such as resins other than component (A), such as epoxy resins, curing agents, curing accelerators, thermal polymerization inhibitors and antioxidants, plasticizers, fillers other than hollow silica, leveling agents, defoamers, surfactants, and coupling agents, 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, silica, 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.

The photosensitive resin composition of the present invention preferably contains 80% or more by mass of the unsaturated group-containing photosensitive resin (A), the photopolymerizable monomer having at least two ethylenically unsaturated bonds (B), the photopolymerization initiator (C), the light-shielding component (D), and the hollow silica particles (E) in a total amount of 80% by mass or more, and more preferably 90% by mass or more, in the solids (including the monomer that becomes solid after curing) excluding the solvent (F). The amount of the solvent varies depending on the target viscosity, but is preferably 40 to 90% by mass of the total amount.

A light-shielding 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 by irradiating with light (including ultraviolet light, radiation, etc.). By using a photomask or the like to provide areas that are exposed to light and areas that are not, only the areas that are exposed to light are cured and the other areas are dissolved in an alkaline solution, the desired pattern can be obtained.

A color filter having the light-shielding film of the present invention as a black matrix can be produced, for example, by forming a light-shielding film having a thickness of 1.0 to 2.0 μm on a transparent substrate, forming red, blue, and green pixels by photolithography after the light-shielding film is formed, and by injecting red, blue, and green inks into the light-shielding film by an inkjet process.

The light-shielding film obtained by curing the photosensitive resin composition of the present invention can also be used as a black column spacer in a liquid crystal display device. For example, a single black resist can be used to create multiple sections with different film thicknesses, with one functioning as a spacer and the other functioning as a black matrix.

Specific examples of each step in the method for forming a light-shielding film by applying and drying a photosensitive resin composition are given below.

The photosensitive resin composition can be applied to a substrate by any of the known methods, such as immersion in a solution, spraying, or using a roller coater, land coater, slit coater, or spinner. After application to the desired thickness by these methods, the solvent is removed (prebaking) to form a coating. Prebaking is performed by heating in an oven or hot plate, vacuum drying, or a combination of these. The heating temperature and heating time in prebaking can be appropriately selected depending on the solvent used, but it is preferable to perform the prebaking 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) is performed at 180 to 250°C for 20 to 100 minutes. This post-baking is performed for the purpose of increasing the adhesion between the patterned cured film (light-shielding film) and the substrate, etc. As with pre-baking, this is performed by heating in an oven, hot plate, etc. The patterned cured film (light-shielding film) of the present invention is formed through various steps using the photolithography method. Then, polymerization or curing (both are sometimes collectively referred to as curing) is completed by heat, and a light-shielding film having the desired pattern can be obtained. The curing temperature at this time is preferably 160 to 250°C.

As described above, the photosensitive resin composition for black resist of the present invention is not only suitable for forming fine patterns by exposure to light, alkaline development, and other procedures, but also allows a light-shielding film with excellent light-shielding properties, adhesion, electrical insulation, heat resistance, and chemical resistance to be obtained even when a pattern is formed by conventional screen printing.

The photosensitive resin composition for black resist of the present invention can be suitably used as a coating material. In particular, the ink for color filters used in liquid crystal display devices or imaging devices, and the light-shielding film formed therefrom are useful as color filters, black matrices for liquid crystal projection, and the like. The photosensitive resin composition for black resist of the present invention can be used as a color filter ink for color liquid crystal displays, as well as an ink material for color separation or light shielding in various multicolor display devices such as organic electroluminescent devices represented by organic EL elements, color liquid crystal display devices, color facsimiles, and image sensors. The color filter of the present invention can reduce the reflection of external light at the interface between the colored layer (including the black resist layer) and the substrate, and, for example, the reflection of light emitted from an organic EL element when used in an organic EL element. In other words, it is possible to improve the contrast in bright areas by reducing the reflection of external light, and improve the light-emitting efficiency by improving the light extraction efficiency from the light-emitting side.

The following describes the embodiments of the present invention in detail based on examples and comparative examples, but the present invention is not limited to these.

First, we will explain the synthesis examples of the polymerizable 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 concentration (wt%) = 100 x (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: TSKgelSuper H-2000 (2 columns) + TSKgelSuper H-3000 (1 column) + TSKgelSuper H-4000 (1 column) + TSKgelSuper H-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.).

[Refractive index]
The refractive index of the silica particles was determined using an Abbe refractometer.

[Porosity]
The porosity of the silica particles was determined using a transmission electron microscope.

The abbreviations used in the Synthesis Examples and Comparative Synthesis Examples are as follows.
BPFE: 9,9-bis(4-hydroxyphenyl)fluorene and chloromethyl
Reaction product with oxirane. In the compound of formula (1), X is fluoro.
A compound in which R ₁ and R ₂ 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 a polymerizable unsaturated group-containing alkali-soluble resin (A). The solid content concentration of the obtained resin solution was 56.1% by mass, the acid value (solid content equivalent) was 103 mgKOH/g, and the Mw by GPC analysis was 3600.

The photosensitive resin compositions of Examples 1 to 5 and Comparative Examples 1 and 2 were prepared in the amounts (values are mass %) shown in Table 1. The ingredients used in the table are as follows:

(Polymerizable unsaturated group-containing alkali-soluble resin)
(A): Alkali-soluble resin solution obtained in the above Synthesis Example (solid content concentration: 56.1% by mass)

(Photopolymerizable monomer)
(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-carboxylate
Rubazol-3-yl]-, 1-(0-acetyloxime) (Irgac
URE 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
"-Cruz" is a registered trademark of the company.

(Carbon Black Dispersion)
(D): PGMEA dispersion (solid content 34.8% by mass) with a carbon black concentration of 25.0% by mass and a polymer dispersant concentration of 10.0% by mass

(Silica Dispersion)
(E)-1: Hollow silica isopropanol dispersion sol
(JGC Catalysts and Chemicals, solid content 20% by weight, average particle size approx. 50 nm,
Porosity 30% by volume, refractive index 1.30)
(E)-2: Hollow silica isopropanol dispersion sol
(JGC Catalysts and Chemicals, solid content 20% by weight, average particle size approx. 60 nm,
Porosity 37% by volume, refractive index 1.25)
(E)-3: Hollow silica isopropanol dispersion sol
(JGC Catalysts and Chemicals, solid content 20% by weight, average particle size approx. 75 nm,
Porosity 46% by volume, refractive index 1.21)
(E)-4: Hollow silica PGMEA dispersion sol
(JGC Catalysts and Chemicals, solid content 20% by weight, average particle size approx. 75 nm,
Porosity 46 volume%, refractive index 1.25)
(E)-5: Solid silica isopropanol dispersion sol
(Nissan Chemical Co., Ltd., solid content 30% by weight, average particle size approx. 80 nm, void
0% by volume, refractive index 1.46)

(solvent)
(F)-1: Propylene glycol monomethyl ether acetate (PGMEA)
(F)-2: Cyclohexanone (ANON)

[Example]
Photosensitive resin compositions of Examples 1 to 5 and Comparative Examples 1 and 2 were prepared in the amounts (values are parts by mass) shown in Table 1. The ingredients used in the table are as follows. Note that (F)-1 and (F)-2 are amounts that do not include the solvents in (A) and (D)-4 and the solvent in (E).

[evaluation]
The photosensitive resin compositions for black resist of Examples 1 to 5 and Comparative Examples 1 and 2 were used to carry out the following evaluations.

(Creation of hardened film (light-shielding film) for evaluating development characteristics)
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/ ^cm2 from a low-pressure mercury lamp, using a spin coater so that the film thickness after heat curing treatment would be 1.2 μm, and a hardened film (light-shielding film) was produced by pre-baking it at 90°C for 1 minute using a hot plate. Next, the exposure gap was adjusted to 100 μm, 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/ ^cm2 was irradiated from an ultra-high pressure mercury lamp with an i-line illuminance of 30 mW/ ^cm2 to cause a photocuring reaction of the photosensitive portion.

Next, the exposed cured film (light-shielding film) was subjected to a development treatment at 25° C. with a 0.04% potassium hydroxide solution at a shower pressure of 1 kgf/ ^cm2 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/ ^cm2 to remove unexposed portions of the cured film (light-shielding film) to form a cured film pattern on a glass substrate. The film was then main-cured (post-baked) at 120° C. for 60 minutes using a hot air dryer, thereby obtaining cured films (light-shielding films) according to Examples 1 to 5 and Comparative Examples 1 and 2.

The cured films (light-shielding films) obtained by curing the photosensitive resin compositions for black resists of Examples 1 to 5 and Comparative Examples 1 and 2 obtained above were evaluated for the following items, and the results are shown in Table 2.

[Evaluation of Development Characteristics]
(Pattern line width)
(Evaluation Method)
The pattern line width after main curing (post-baking) was measured with a length measuring microscope "XD-20" (Nikon Corporation) for a mask width of 10 μm. The pattern line width was evaluated in the cases of BT+10 seconds and BT+20 seconds.

(Evaluation Criteria)
◯: The pattern line width is within the range of 10±2 μm. ×: The pattern line width is outside the range of 10±2 μm.

(Pattern Linearity)
(Evaluation Method)
The 10 μm mask pattern after the main curing (post-baking) was observed using an optical microscope. The pattern linearity was evaluated in the cases of BT+10 seconds and BT+20 seconds. A score of △ or higher was considered to be acceptable.

(Evaluation Criteria)
◯: No jagged edges are observed at the edge of the pattern. △: Jagged edges are observed in some areas at the edge of the pattern. ×: Jagged edges are observed throughout the edge of the pattern.

(Preparation of cured film (light-shielding film) for optical density (OD) evaluation)
The photosensitive resin compositions shown in Tables 1 and ² were 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/cm2 from a low pressure mercury lamp, using a spin coater so that the film thickness after heat curing treatment would be 1.1 μm, and the substrate was prebaked at 90°C for 1 minute using a hot plate to prepare a hardened film (light-shielding film). Without covering with a negative photomask, ultraviolet light of 50 mJ/ ^cm2 was irradiated from an ultra-high pressure mercury lamp with an i-line illuminance of 30 mW/ ^cm2 to carry out a photocuring reaction.

Next, the exposed cured film (light-shielding film) was developed at 25° C. with a 0.05% potassium hydroxide solution at a shower pressure of ¹ kgf/cm2 for 60 seconds from the development time (break time = BT) at which a pattern began to appear, and then washed with water sprayed at 5 kgf/ ^cm2 to remove the unexposed parts of the cured film (light-shielding film) to form a cured film pattern on the glass substrate. The film was then main-cured (post-baked) at 230° C. for 30 minutes using a hot air dryer, thereby obtaining the cured films (light-shielding films) according to Examples 1 to 5 and Comparative Examples 1 and 2.

[Optical Density Evaluation]
(Evaluation Method)
The optical density (OD) of the prepared cured film (light-shielding film) was evaluated using a Macbeth transmission densitometer. The film thickness of the cured film (light-shielding film) formed on the substrate was 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)

[Reflectance evaluation]
(Evaluation Method)
For a substrate with a cured film (light-shielding film) prepared in the same manner as for the cured film (light-shielding film) for evaluation of optical density (OD), the reflectance of each of the cured film (light-shielding film) side and the substrate (glass substrate) side was measured at an incident angle of 2° using an ultraviolet-visible-infrared spectrophotometer "UH4150" (manufactured by Hitachi High-Tech Science Corporation).

It was confirmed that the photosensitive resin compositions for black resists of Examples 1 to 5 had a lower reflectance than a system without silica (Comparative Example 1). In addition, it was confirmed that, compared to a system using solid silica (Comparative Example 2), the reflectance was reduced not only on the glass substrate side but also on the coating film (light-shielding film) side. In addition, the cured films (light-shielding films) obtained by curing the photosensitive resin compositions for black resists of Examples 1 to 5 all had good pattern linearity, suggesting that the hollow silica was more uniformly dispersed in the cured film than in a system using solid silica.

According to the photosensitive resin composition of the present invention, it is possible to provide a photosensitive resin composition for black resist having high light-shielding property and low reflectance, and a light-shielding film and a color filter using the same. Furthermore, when the light-shielding film of the present invention is formed on a transparent substrate, it contributes to realizing not only low reflectance on the transparent substrate side but also low reflectance on the coated surface side of the light-shielding film, and is therefore useful as a light-shielding film for sensors of various display devices and solid-state imaging devices.

Claims (7)

(A) an unsaturated group-containing photosensitive resin;
(B) a photopolymerizable monomer having at least two ethylenically unsaturated bonds;
(C) a photopolymerization initiator;
(D) at least one light-shielding component selected from a black pigment, a mixed color pigment, and a light-shielding material;
(E) silica particles;
A photosensitive resin composition for black resist comprising:
The silica particles as the component (E) are hollow particles.
Photosensitive resin composition for black resist. 2. The photosensitive resin composition for black resist according to claim 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 derived from a bisphenol represented by general formula (1) and (meth)acrylic acid with a polybasic carboxylic acid or an anhydride thereof.

(In formula (1), 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 (2) or a single bond; and l represents an integer of 0 to 10.)

The photosensitive resin composition for black resist according to claim 1 or 2, wherein the average particle size of the silica particles (E) is 40 to 100 nm. The photosensitive resin composition for black resist according to any one of claims 1 to 3, wherein the porosity of the silica particles (E) is 20% by volume or more. The photosensitive resin composition for black resist according to any one of claims 1 to 4, wherein the refractive index of the silica particles (E) is 1.10 to 1.41. A light-shielding film obtained by curing the photosensitive resin composition for black resist according to any one of claims 1 to 5. A color filter having the light-shielding film according to claim 6 as a black matrix.