JP2023051765A - Photosensitive resin composition, cured film, color filter, touch panel and display device - Google Patents

Abstract

To provide a photosensitive resin composition which enables production of a cured film that has both desired light-shielding property and reflectance, and prevents jaggies in a pattern edge part in pattern formation.SOLUTION: A photosensitive resin composition contains (A) an unsaturated group-containing alkali-soluble resin, (B) a photopolymerizable compound having at least two or more unsaturated bonds, (C) a photopolymerization initiator, (D) at least one light-shielding component selected from a black pigment, a mixed organic pigment and a light-shielding material, and (E) fine particles having a refractive index of 1.50 or more and 1.80 or less.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a photosensitive resin composition, a cured film, a color filter, a touch panel and a display device.

In recent years, with the development of mobile terminals, the number of display devices such as touch panels and liquid crystal panels used outdoors or in vehicles is increasing. In the display device, the outer frame of the touch panel is provided with a light-shielding film to block light leakage around the liquid crystal panel on the back, and the liquid crystal panel is provided with a light-shielding film to suppress light from leaking from the screen during black display, and A black matrix, which is a kind of light-shielding film, is provided to suppress color mixture between adjacent color resists.

In a display device or the like, in order to suppress light leakage or the like and improve the visibility of the screen of the display device or the like, the black pigment concentration in the light shielding film is increased to increase the light shielding property of the light shielding film (light shielding film (lower the light transmittance of the material). Since the refractive index of the black pigment is higher than the refractive index of the transparent base material and the curable resin, increasing the black pigment concentration in the light-shielding film causes the surface of the transparent base material on which the light-shielding film is formed to , the reflectance becomes high when viewed from the opposite side. As a result, reflection at the interface between the light-shielding film formed on the transparent base material and the transparent base material increases, resulting in reflections on the light-shielding film and the difference in reflectance between the colored portion of the color filter and the black matrix boundary. occurs.

Therefore, there is a demand for a photosensitive resin composition for black resists having both high light-shielding properties and low reflectance, and light-shielding films and color filters obtained by curing the same.

For example, Patent Document 1 discloses a black photosensitive resin composition 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, it is possible to form a black matrix that achieves both high light shielding properties and low reflectance.

JP 2015-161815 A

However, as a result of investigation by the present inventors, the black photosensitive resin composition described in Patent Document 1 has both desired light shielding properties and reflectance, and in pattern formation, the pattern edge portion has serrations. In some cases, it was not possible to obtain a light-shielding film that does not occur.

The present invention has been made in view of this point, has a high light-shielding property and low reflectance, a photosensitive resin composition capable of forming a high-definition pattern, and a cured film obtained by curing the same, An object of the present invention is to provide a color filter and a touch panel having a cured film, and a display device having the color filter and the touch panel.

That is, the gist of the present invention is as follows.
(1) (A) unsaturated group-containing alkali-soluble resin, (B) photopolymerizable compound having at least two unsaturated bonds, (C) photopolymerization initiator, (D) black pigment, color mixture A photosensitive resin composition comprising at least one light-shielding component selected from organic pigments and light-shielding materials, and (E) fine particles having a refractive index of 1.50 to 1.80 or less.

(2) The photosensitive resin composition according to (1), wherein the fine particles (E) are aluminum oxide particles.
(3) The photosensitive resin composition according to (1) or (2), wherein the fine particles (E) have an average particle size of 10 to 300 nm.
(4) The photosensitive resin composition according to any one of (1) to (3), wherein the proportion of the (E) fine particles in the solid content is 1 to 30% by mass.

(5) A cured film having a thickness of 1 μm obtained by curing the photosensitive resin composition with light has a light blocking degree OD [μm ⁻¹ ] of 2.6 or more, and the reflectance [%] of the cured film. is 6.5 or less, and the value obtained by dividing the reflectance of the cured film by the light shielding degree OD is less than 1.65, (1) to (4). The photosensitive resin composition according to any one of .

(6) A cured film obtained by curing the photosensitive resin composition according to any one of (1) to (5).
(7) A color filter having the cured film according to (6) as a black matrix.
(8) A touch panel having the cured film according to (6) as a black matrix.
(9) A display device comprising the color filter described in (7) or the touch panel described in (8).

According to the present invention, a photosensitive resin composition capable of obtaining a cured film having high light shielding properties and low reflectance, a cured film obtained by curing the same, a color filter and touch panel having the cured film, and the color A display device having a filter and a touch panel can be provided.

The present invention will be described in detail below.
The unsaturated group-containing alkali-soluble resin, which is the component (A) according to the present embodiment, preferably has a polymerizable unsaturated group and an acidic group for expressing alkali solubility in one molecule, More preferably, it contains both a polymerizable unsaturated group and a carboxy group. Any of the above resins can be widely used without any particular limitation.

Examples of the unsaturated group-containing alkali-soluble resin include epoxy compounds having two glycidyl ether groups derived from bisphenols (hereinafter also referred to as "bisphenol-type epoxy compounds represented by general formula (1)"). There is an epoxy (meth)acrylate acid adduct obtained by reacting (meth)acrylic acid and reacting the obtained compound having a hydroxy group with a polybasic carboxylic acid or its anhydride. An epoxy compound derived from bisphenols means an epoxy compound obtained by reacting a bisphenol with epihalohydrin or an equivalent thereof. In addition, "(meth)acrylic acid" is a generic term for acrylic acid and methacrylic acid, and means one or both of them.

The unsaturated group-containing alkali-soluble resin as the component (A) is preferably a bisphenol type epoxy compound represented by the general formula (1). Good developing properties can be obtained by employing the bisphenol type epoxy compound represented by the general formula (1).

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

The bisphenol-type epoxy compound represented by the general formula (1) is an epoxy compound having two glycidyl ether groups obtained by reacting bisphenols and epichlorohydrin. Since this reaction generally involves oligomerization of a diglycidyl ether compound, it 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-hydroxy-3,5-dichlorophenyl)hexafluoropropane, bis(4-hydroxyphenyl)dimethylsilane, bis(4-hydroxy-3, 5-dimethylphenyl)dimethylsilane, bis(4-hydroxy-3,5-dichlorophenyl)dimethylsilane, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3,5-dichlorophenyl)methane, bis(4- hydroxy-3,5-dibromophenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4 -hydroxy-3,5-dichlorophenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, bis(4-hydroxyphenyl) ) ether, bis(4-hydroxy-3,5-dimethylphenyl)ether, bis(4-hydroxy-3,5-dichlorophenyl)ether, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis (4-hydroxy-3-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. included. Among these, bisphenols having a fluorene-9,9-diyl group are preferred.

In addition, examples of (a) dicarboxylic acid or tricarboxylic acid monoanhydride that reacts with the hydroxyl group in the epoxy (meth)acrylate molecule obtained by reacting such an epoxy compound with (meth)acrylic acid includes chain hydrocarbon dicarboxylic acid or tricarboxylic acid unianhydrides, alicyclic dicarboxylic acid or tricarboxylic acid unianhydrides, aromatic dicarboxylic acid or tricarboxylic acid unianhydrides, and the like. Here, examples of monoanhydrides of chain hydrocarbon dicarboxylic or tricarboxylic acids include succinic acid, acetylsuccinic acid, maleic acid, adipic acid, itaconic acid, azelaic acid, citralic acid, malonic acid, glutaric acid, Acid monoanhydrides such as citric acid, tartaric acid, oxoglutaric acid, pimelic acid, sebacic acid, suberic acid and diglycolic acid are included. Furthermore, acid monoanhydrides of dicarboxylic acids or tricarboxylic acids into which arbitrary substituents have been introduced are included. Examples of alicyclic dicarboxylic acid or tricarboxylic acid monoanhydrides include acid monoanhydrides such as cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, and norbornane dicarboxylic acid. . Further, acid monoanhydrides of dicarboxylic acids or tricarboxylic acids into which optional substituents have been introduced are also included. Examples of the unianhydrides of aromatic dicarboxylic acids or tricarboxylic acids include unianhydrides of phthalic acid, isophthalic acid, trimellitic acid, and the like. Furthermore, monoanhydrides of dicarboxylic acids or tricarboxylic acids into which arbitrary substituents have been introduced are included.

In addition, the (b) tetracarboxylic acid dianhydride to be reacted with the epoxy (meth)acrylate includes a chain hydrocarbon tetracarboxylic acid dianhydride, an alicyclic tetracarboxylic acid dianhydride, or an aromatic The dianhydrides of group tetracarboxylic acids are used. Examples of acid dianhydrides of chain hydrocarbon tetracarboxylic acids include acid dianhydrides such as butanetetracarboxylic acid, pentanetetracarboxylic acid, and hexanetetracarboxylic acid. Furthermore, acid dianhydrides of tetracarboxylic acids into which optional substituents have been introduced, and the like are included. Examples of acid dianhydrides of alicyclic tetracarboxylic acids include acid dianhydrides such as cyclobutanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, cycloheptanetetracarboxylic acid, and norbornanetetracarboxylic acid. includes things. Furthermore, acid dianhydrides of tetracarboxylic acids into which optional substituents have been introduced, and the like are included. Examples of acid dianhydrides of aromatic tetracarboxylic acids include acid dianhydrides such as pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, and biphenylethertetracarboxylic acid. Furthermore, acid dianhydrides of tetracarboxylic acids into which optional substituents have been introduced, and the like are included.

The molar ratio (a)/(b) of (a) dicarboxylic acid or tricarboxylic acid dianhydride and (b) tetracarboxylic acid dianhydride reacted with epoxy (meth)acrylate is 0.01 or more. It is preferably 10.0 or less, more preferably 0.02 or more and less than 3.0. If the molar ratio (a)/(b) deviates from the above range, the optimum molecular weight for forming a photosensitive resin composition having good photopatterning properties cannot be obtained, which is not preferable. The smaller the molar ratio (a)/(b), the larger the molecular weight and the lower the alkali solubility.

In addition, the reaction between the epoxy compound and (meth)acrylic acid, and the 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 used. can be adopted. The unsaturated group-containing alkali-soluble 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. The weight average molecular weight (Mw) can be measured using, for example, gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation). Further, the acid value can be titrated with a 1/10 N-KOH aqueous solution using, for example, a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.).

Another example of a preferable resin as the unsaturated group-containing alkali-soluble resin as the component (A) is a copolymer of (meth)acrylic acid, (meth)acrylic acid ester, etc., containing a (meth)acryloyl group and Resins with carboxy groups are included. Examples of the resin include a copolymer obtained by copolymerizing (meth)acrylic acid esters containing glycidyl (meth)acrylate in a solvent, reacting (meth)acrylic acid, and finally dicarboxylic acid. Alternatively, a polymerizable unsaturated group-containing alkali-soluble resin obtained by reacting an anhydride of tricarboxylic acid is included. The copolymer, shown in JP-A-2014-111722, hydroxyl groups at both ends derived from diester glycerol esterified with (meth) acrylic acid 20 to 90 mol% of repeating units, and together with this A copolymer composed of 10 to 80 mol% of repeating units derived from one or more polymerizable unsaturated compounds, having a number average molecular weight (Mn) of 2000 to 20000 and an acid value of 35 to 120 mgKOH/g. , And shown in JP 2018-141968, a unit derived from a (meth) acrylic acid ester compound, a unit having a (meth) acryloyl group and a di- or tricarboxylic acid residue, weight average A polymerizable unsaturated group-containing alkali-soluble resin having a molecular weight (Mw) of 3,000 to 50,000 and an acid value of 30 to 200 mg/KOH can be referred to.

The content of component (A) is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 80% by mass or less, relative to the total mass of solids. (A) It becomes possible to form a high-resolution pattern as said content of a component is 10 mass % or more.

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

Examples of the photopolymerizable compound having at least two unsaturated bonds in the component (B) according to the present embodiment 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, tripropylene glycol diacrylate, glycerol (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 tetra(meth)acrylate, glycerol tri(meth)acrylate, sorbitol Penta(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, phosphazene alkylene oxide-modified hexa(meth)acrylate, caprolactone-modified dipentaerythritol hexa(meth)acrylate ) (meth) acrylic acid esters such as acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and other hydroxyl group-containing (meth) acrylic acid esters; bisphenol A type epoxy (meth) acrylate , bisphenol F-type epoxy (meth)acrylate, bisphenolfluorene-type epoxy (meth)acrylate, diphenylfluorene-type epoxy (meth)acrylate, phenol novolac-type epoxy (meth)acrylate, cresol novolak-type epoxy (meth)acrylate, phenol aralkyl-type epoxy Epoxy (meth)acrylates such as (meth)acrylates; Compounds having ethylenic double bonds include dendritic polymers having (meth)acryl groups. One type of these photopolymerizable compounds may be used alone, or two or more types may be used in combination. In addition, the photopolymerizable compound having at least two ethylenically unsaturated bonds can play a role of cross-linking the molecules of the polymerizable unsaturated group-containing alkali-soluble resin, and exhibits this function. For this purpose, it is preferable to use one having 3 or more unsaturated bonds. The acrylic equivalent obtained by dividing the molecular weight of the photopolymerizable compound by the number of (meth)acrylic groups in one molecule is preferably 50 to 300, more preferably 80 to 200. In addition, (B) component does not have a free carboxy group.

The mixing ratio of component (A) and component (B) is preferably 30/70 to 90/10, preferably 60/40 to 80/20, in terms of weight ratio (A)/(B). more preferred. When the blending ratio of component (A) is 30/70 or more, the cured product after photocuring is less likely to become brittle, and the acid value of the coating film in the unexposed area is less likely to decrease, resulting in solubility in an alkaline developer. can suppress the decrease in Therefore, problems such as the pattern edge being serrated or not being sharp are less likely to occur. Further, when the mixing ratio of the component (A) is 90/10 or less, the proportion of the photoreactive functional groups in the resin is sufficient, so that a desired crosslinked structure can be formed. In addition, since the acid value of the resin component is not too high, the solubility in the alkaline developer in the exposed area is unlikely to increase, so that the formed pattern does not have a narrower line width than the target line width or the pattern is missing. can be suppressed.

Examples of photopolymerization initiators as component (C) include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, and p-tert-butylacetophenone. benzophenones such as acetophenones such as benzophenone, 2-chlorobenzophenone, p,p'-bisdimethylaminobenzophenone; benzoin ethers such as benzyl, 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 Biimidazole compounds such as imidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, 2,4,5-triarylbiimidazole; 2-trichloromethyl-5-styryl-1,3, 4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4- Halomethylthiazole compounds such as oxadiazole; 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl)-1,3,5 -triazine, 2-phenyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-chlorophenyl)-4,6-bis(trichloromethyl-1,3,5-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3, 5-triazine, 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4,5-trimethoxystyryl)-4,6-bis Halomethyl-S-triazine compounds such as (trichloromethyl)-1,3,5-triazine and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine; 1,2-octanedione, 1-[4-(phenylthio)phenyl]-,2-(O-benzoyloxime), 1-(4-phenylsulfanylphenyl)butane-1,2-dione-2-oxime-O -benzoate, 1-(4-methylsulfanylphenyl)butane-1,2-dione-2-oxime-O-acetate, 1-(4-methylsulfanylphenyl)butan-1-one oxime-O-acetate, 4- O-acyloxime compounds such as ethoxy-2-methylphenyl-9-ethyl-6-nitro-9H-carbazol-3-yl-O-acetyloxime; benzyldimethylketal, thioxanthone, 2-chlorothioxanthone, 2, Sulfur compounds such as 4-diethylthioxanthone, 2-methylthioxanthone, and 2-isopropylthioxanthone; Anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, and 2,3-diphenylanthraquinone; Azobisisobutyl Organic peroxides such as lonitrile, benzoyl peroxide and cumene peroxide; thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole and 2-mercaptobenzothiazole; tertiary amines such as triethanolamine and triethylamine etc. are included. These photopolymerization initiators may be used alone or in combination of two or more.

Examples of O-acyloxime compounds that can be preferably used include O-acyloxime photopolymerization initiators represented by general formulas (3) and (4). Among these compounds, when the light-shielding component is used at a high concentration, it is preferable to use an O-acyloxime-based photopolymerization initiator having a molar extinction coefficient of 10,000 or more at 365 nm. In addition, the "photopolymerization initiator" as used in the field of this invention is used in the meaning containing a sensitizer.

式（３）中、Ｒ_５、Ｒ_６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の複素環基であり、Ｒ_７はＣ１～Ｃ１５のアルキル基、Ｃ６～Ｃ１８のアリール基またはＣ７～Ｃ２０のアリールアルキル基である。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 (3), R ₅ and R ₆ are each independently a C1-C15 alkyl group, a C6-C18 aryl group, a C7-C20 arylalkyl group or a C4-C12 heterocyclic group; ₇ is 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 halogen, and the alkylene portion may be an unsaturated bond, an ether bond, It may contain a thioether bond and an ester bond. Also, the alkyl group may be a linear, branched or cyclic alkyl group.

In formula (4), R ₈ and R ₉ are each independently a linear or branched alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a cycloalkylalkyl group, or It is an alkylcycloalkyl group or a phenyl group optionally substituted with an alkyl group having 1 to 6 carbon atoms. R ₁₀ is independently a linear or branched alkyl or alkenyl group having 2 to 10 carbon atoms, and some of the —CH ₂ — groups in the alkyl or alkenyl group are substituted with —O— groups may have been Furthermore, some of the hydrogen atoms in these R ₈ to R ₁₀ groups may be substituted with halogen atoms.

The amount of the photopolymerization initiator used as component (C) is preferably 3 to 30 parts by weight, preferably 5 to 20 parts by weight, based on the total of 100 parts by weight of each component (A) and (B). is more preferable. When the blending ratio of the component (C) is 3 parts by weight or more, the sensitivity is good and a sufficient photopolymerization speed can be obtained. When the blending ratio of the component (C) is 30 parts by weight or less, a suitable sensitivity can be obtained, and a desired pattern line width and desired pattern edge can be obtained.

The light-shielding components such as black pigments, mixed-color organic pigments, and light-shielding materials, which are the component (D) according to the present embodiment, have an average particle size of 1 to 1000 nm (laser diffraction/scattering method particle size distribution meter or dynamic light scattering method Any known light-shielding component can be used without particular limitation, as long as it is dispersed with a mean particle size measured by a particle size distribution meter.

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

Examples of mixed color organic pigments as component (D) include azo pigments, condensed azo pigments, azomethine pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, isoindoline pigments, dioxazine pigments, threne pigments, perylene pigments, and perinone pigments. , quinophthalone pigments, diketopyrrolopyrrole pigments, and thioindigo pigments.

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

Examples of organic pigments that can be used when a mixed color organic pigment is used as the component (D) include, but are not limited to, those with the following numbers in terms of 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.

Among these, black pigments are preferred, and carbon black is more preferred.

The average primary particle size of carbon black is preferably 5 nm or more and 60 nm or less, more preferably 10 nm or more and 50 nm or less, and even more preferably 20 nm or more and 45 nm or less. In the present specification, the particle size or average primary particle size of the light-shielding component refers to the average value of the major and minor diameters obtained by observing the particles or primary particles of the light-shielding component with an electron microscope, for 1,500 light-shielding components. means the arithmetic mean value of The larger the average primary particle size of carbon black, the easier it is to disperse at high concentrations. By setting the average primary particle size of carbon black to a size that is not excessive, it is possible to suppress secondary particle shape defects and decrease in surface roughness.

Further, the DBP oil absorption of carbon black is preferably 100 ml/100 g or less. DBP oil absorption means the capacity of dibutyl phthalate (DBP) absorbed by 100 g of carbon black (JIS K 6217-4 (2017)). When the DBP oil absorption of carbon black is within the above range, the resistance value and blackness of the cured film can be increased, and deterioration in coatability due to the increase in viscosity of the photosensitive resin composition can be suppressed.

Carbon black preferably has a pH of 2 or more and 10 or less, more preferably 5 or more and 9 or less, and even more preferably 4 or more and 8 or less. The pH value means a value obtained by measuring a mixture of carbon black and distilled water with a glass electrode pH meter. The higher the carbon black pH, the more stable the carbon black. Adhesion of the cured film to the substrate can be further enhanced by adjusting the pH of the carbon black to a range that is not excessive.

Further, the carbon black preferably has an ash content of 1.0% or less. When the ash content is 1.0% or less, the resistance value of the cured film can be further increased.

Further, carbon black preferably has a specific surface area of 20 m ² /g or more and 300 m ² /g or less. When the specific surface area is 20 m ² /g or more, the shape of the cured film tends to be stable. When the specific surface area is 300 m ² /g or less, the necessary amount of dispersant, dye, etc. can be reduced, so the cost can be further suppressed.

Carbon black preferably has an acidic functional group on its surface by oxidation treatment. In particular, it is preferable to have two or more types of acidic functional groups on the surface by multiple types of oxidation treatments. The acidic functional group can enhance the dispersibility of carbon black. Examples of the oxidation treatment include ozone gas, nitric acid, sodium hypochlorite, hydrogen peroxide, nitrogen monoxide gas, nitrogen dioxide gas, anhydrous sulfuric acid, fluorine gas, concentrated sulfuric acid, nitric acid, and various peroxides. processing is included. Examples of the above acidic functional groups include hydroxyl group, oxo group, hydroperoxy group, carbonyl group, carboxyl group, peroxycarboxylic acid group, aldehyde group, ketone group, nitro group, nitroso group, amide group, imide group, sulfonic acid group. , sulfinic acid group, sulfenic acid group, thiocarboxylic acid group, chlorosyl group, chloryl group, perchloryl group, iodosyl group, iodyl group and the like.

In addition, the component (D) may be surface-treated by coating the surface with a dye. In particular, carbon black whose surface is coated with a dye enhances the developability of the photosensitive resin composition, and enhances the adhesion to the substrate of the cured film obtained by curing this, reproducibility of fine lines, and light shielding, It is also possible to increase the resistance of the cured film.

Any dye can be used as long as it can be adsorbed on the surface of the light-shielding component, and basic dyes, acid dyes, direct dyes, reactive dyes, and the like can be used. At this time, when an acidic functional group is imparted (oxidized) to the surface of the light-shielding component (especially carbon black) in order to increase the dispersibility, the acidic functional group is easily interacted with. Dyes (especially acid dyes having a sulfonic acid group or a carboxyl group) are preferred. In addition, from the viewpoint of suppressing reaction with the acidic group of component (A), acid dyes or nonionic dyes are preferable to dyes having amino groups or the like. From the viewpoint of further enhancing the light-shielding properties of the cured film, a dark-colored dye is preferred.

Specific examples of the above dyes include food coloring dyes such as Food Black No.1, Food Black No.2, Food Red No.40, Food Blue No.1, Food Yellow No.7, Bernacid Red 2BMN, Basacid Black X34 (BASF X-34) (manufactured by BASF), Kayanol Red 3BL (manufactured by Nippon Kayaku Company), Dermacarbon 2GT (manufactured by Sandoz), Telon Fast Yellow 4GL-175, BASF Basacid Black SE 0228, Basacid Black X34 (BASF X -34) (manufactured by BASF), Basacid Blue 750 (manufactured by BASF), Bernacid Red (manufactured by Bemcolors, Poughkeepsie, N.Y.), BASF Basacid Black SE 0228 (manufactured by BASF) and other acid dyes of various colors, Pontamine Brilliant Bond Blue A and other Pontamine Brilliant Bond Blue A and other Pontamine® dyes (Bayer Chemicals Corporation, Pittsburgh, PA); Cartasol Yellow GTF Presscake (Sandoz, Inc); Cartasol Yellow GTF Liquid Special 110 ( Sandoz, Inc.); Yellow Shade 16948 (Tricon), Direct Brilliant Pink B (Crompton & Knowles), Carta Black 2GT (Sandoz, Inc.), Sirius Supra Yellow GD 167, Cartasol Brilliant Yellow 4GF (manufactured by Sandoz);, Pergasol Yellow CGP (manufactured by Ciba-Geigy), Pyrazol Black BG (manufactured by JCI), Diazol Black RN Quad (manufactured by JCJ), Pontamine Brilliant Bond Blue; Direct dyes, Cibacron Brilliant Red 3B-A (Reactive Red 4) (Aldrich Chemical, Milwaukee, WI), Drimarene Brilliant Red X-2B (Reactive Red 56) (Pylam Products, Inc. Tempe, AZ), Levafix Brilliant Red E-4B, Levafix Brilliant Red F-6BA, and similar dyes from Levafix® dyes Dystar L.P. (Charlotte, NC), Procion Red H8B (Reactive Red 31) (JCI America), Reactive dyes of each color such as Neozapon Red 492 (manufactured by BASF), Orasol Red G (manufactured by Ciba-Geigy), Aizen Spilon RedC-BH (manufactured by Hodogaya Chemical Company), Spirit Fast Yellow 3G, Aizen Spilon Yellow C -GNH (manufactured by Hodogaya Chemical Company), Orasol Black RL (manufactured by Ciba-Geigy), Orasol Black RLP (manufactured by Ciba-Geigy), Savinyl Black RLS (manufactured by Sandoz), Orasol Blue GN (manufactured by Ciba-Geigy ), Luxol Blue MBSN (manufactured by Morton-Thiokol), and Morfast Black Concentrate A (manufactured by Morton-Thiokol). These may be used alone or in combination of two or more.

The content of the dye is preferably 0.5% by mass or more and 10% by mass or less, more preferably 1% by mass or more and 7% by mass or less, relative to the total mass of component (D). The higher the amount of dye, the higher the resistivity of the cured film. By keeping the amount of the dye to a level that is not excessive, it is possible to suppress the occurrence of aggregation due to the thickening of the photosensitive resin composition due to the excess dye and the inhibition of the dispersibility of other components by the excess dye. can.

Also, the above dyes may be laked with metals or metal salts. By turning the dye into a lake, the dye can be fixed on the surface of the light-shielding component via the metal or metal salt, thereby suppressing the reduction of the above effect due to detachment of the dye from the surface of the light-shielding component. Examples of such metals include aluminum, magnesium, calcium, strontium, barium, manganese, and the like. Examples of the metal salts include hydrochlorides and sulfates of these metals. The content of the metal or metal salt is preferably 0.3-fold mol or more, more preferably 0.5-fold mol, and even more preferably 0.8-fold mol with respect to the dye.

The blending ratio of the light shielding component of component (D) can be arbitrarily determined depending on the desired degree of light shielding. It is more preferably ~70% by mass. When using an organic pigment such as aniline black, cyanine black, lactam black, or a carbon-based light-shielding component such as carbon black as the light-shielding component of component (D), the solid content in the photosensitive resin composition is 40 to 60. % by weight is particularly preferred. When the light-shielding component is 20% by mass or more with respect to the solid content in the photosensitive resin composition, sufficient light-shielding properties can be obtained. When the light-shielding component is 80% by mass or less with respect to the solid content in the photosensitive resin composition, the content of the photosensitive resin, which is the original binder, does not decrease, so the desired development characteristics and film formation are achieved. You can acquire Noh.

The above component (D) is usually mixed with other ingredients as a light-shielding component dispersion dispersed in a solvent, in which case a dispersant can be added. As the dispersant, known compounds used for dispersing pigments (light-shielding components) (compounds commercially available under the names of dispersants, dispersion wetting agents, dispersion accelerators, etc.) can be used without particular limitation. .

Examples of dispersants include cationic polymeric dispersants, anionic polymeric dispersants, nonionic polymeric dispersants, and pigment derivative dispersants (dispersing aids). In particular, the dispersant has a cationic functional group such as an imidazolyl group, pyrrolyl group, pyridyl group, primary, secondary or tertiary amino group as an adsorption point to the colorant, and has an amine value of 1 to 100 mgKOH/ g and a cationic polymeric dispersant having a number average molecular weight (Mn) in the range of 1,000 to 100,000. The blending amount of the dispersant is preferably 1 to 35 parts by mass, more preferably 2 to 25 parts by mass, based on the light-shielding component. High-viscosity substances such as resins generally have the effect of stabilizing dispersion, but those that do not have dispersion-promoting properties are not treated as dispersants. However, it does not limit its use for the purpose of stabilizing the dispersion.

As fine particles as component (E), aluminum oxide, silicon oxide, barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, magnesium carbonate, strontium carbonate, sodium metasilicate, and the like can be used. Among these, fine particles of aluminum oxide are preferred. While the refractive index of a transparent substrate such as glass is about 1.5, the refractive index of carbon black, which is a light shielding component, is about 2.0. By using it, the refractive index of the cured film containing the fine particles can be lowered. The refractive index of the fine particles as component (E) is preferably from 1.50 to 1.80, more preferably from 1.55 to 1.75. The refractive index of aluminum oxide fine particles is 1.74 (literature value), which is located near the middle between the transparent substrate and the light shielding component. It is considered that the reflectance is reduced due to the smaller size. In addition, particles with a large refractive index such as component (E) often have a large specific gravity, and when the photosensitive resin composition is applied onto a substrate, they are unevenly distributed near the interface between the transparent substrate and the cured film. Cheap. Therefore, the component (E) can sufficiently reduce the refractive index difference between the base material and the cured film even in a small amount, thereby suppressing reflection. By reducing the amount of component (E), the relative content of component (D) can be increased, and the optical density of the cured film can be increased. It is believed that these actions enable the component (E) to achieve both high light-shielding properties and low reflectance of the cured film. Furthermore, by reducing the amount of the (E) component, it is possible to prevent the (E) component from causing jagged edges of the pattern.

The aluminum oxide particles used in the present invention are not particularly limited in terms of production method such as gas phase reaction or liquid phase reaction, and shape (spherical or non-spherical).

The average particle size of component (E) is preferably 10 to 300 nm, more preferably 50 to 250 nm, even more preferably 55 to 250 nm. When the average particle diameter of the particles is 10 nm or more, the particle diameter is sufficiently large and the weight of the particles is large, so that they tend to be unevenly distributed near the interface between the transparent substrate and the cured film, so that a sufficient effect of reducing reflectance can be obtained. Cheap. Further, when the average particle diameter of the particles is 300 nm or less, the pattern edges are less likely to be jagged. The average particle size is the average primary particle size when the component (E) consists of primary particles, and the average primary particle size when the component (E) consists of secondary particles.

The blending ratio of component (E) is preferably 1 to 30% by mass, more preferably 2 to 10% by mass, based on the solid content in the photosensitive resin composition. When the content of the component (E) is 1% by mass or more, the refractive index of the cured film is sufficiently increased, and the effect of reducing the reflectance is enhanced. (E) When the content of the component is 30% by mass or less, it is possible to form a highly precise pattern.

The blending ratio of component (D) and component (E) is preferably 85/15 to 99/1, more preferably 92/8 to 98/2, in terms of weight ratio (D)/(E). more preferred. By setting the blending ratio of the component (D) to 85/15 or more, the light shielding property of the cured film can be further enhanced. In addition, by reducing the relative amount of the (E) component, it is possible to make it difficult for the (E) component to cause jaggies at the pattern edge portion. Even if the relative amount of the (E) component is reduced to the above extent, the effect of reducing the reflectance by the (E) component is sufficiently exhibited.

In the photosensitive resin composition of the present invention, it is preferable to use a solvent as component (F) in addition to components (A) to (E). Examples of solvents include alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol; terpenes such as α- or β-terpineol; acetone, methyl ethyl ketone, cyclohexanone, N-methyl-2-pyrrolidone. ketones such as; aromatic hydrocarbons such as toluene, xylene, tetramethylbenzene; cellosolve, methyl cellosolve, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, propylene glycol Glycol ethers such as monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether; 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, a uniform solution composition can be obtained.

In addition, the photosensitive resin composition of the present invention may optionally contain a resin other than the component (A) such as an epoxy resin, a curing agent, a curing accelerator, a thermal polymerization inhibitor and an antioxidant, a plasticizer, and a refractive index. Additives such as fillers, leveling agents, antifoaming agents, surfactants, and coupling agents other than fine particles having a particle size of 1.50 to 1.80 may be added.

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

The photosensitive resin composition of the present invention contains an unsaturated group-containing alkali-soluble resin as the component (A) in the solid content excluding the solvent (the solid content includes a photopolymerizable compound that becomes a solid content after curing). and (B) a photopolymerizable compound having at least two unsaturated bonds, (C) a photopolymerization initiator, and (D) a black pigment, a mixed color organic pigment and a light-shielding material. and (E) fine particles having a refractive index of 1.50 or more and 1.80 or less are preferably contained in a total of 80% by mass or more, more preferably 90% by mass or more. preferable. Although the amount of solvent varies depending on the target viscosity, it is preferably 40 to 90% by weight of the total amount.

Further, a cured film obtained by curing the photosensitive resin composition of the present invention can be obtained, for example, by applying a solution of the photosensitive resin composition to a substrate or the like, drying the solvent, and applying light (including ultraviolet rays, radiation, etc.). Obtained by curing by irradiation. A desired pattern can be obtained by using a photomask or the like to provide portions exposed to light and portions not exposed to light, curing only the portions exposed to light, and dissolving other portions with an alkaline solution.

In addition, the cured film obtained by curing the photosensitive resin composition of the present invention preferably has a light shielding degree OD [μm ⁻¹ ] of a cured film having a thickness of 1 μm of 2.6 or more, and 3.0 or more. It is more preferably 3.3 or more. The cured film obtained by curing the photosensitive resin composition of the present invention preferably has a reflectance of 6.5% or less, more preferably 5.0% or less. In the cured film obtained by curing the photosensitive resin composition of the present invention, the value obtained by dividing the reflectance [%] by the degree of light blocking OD [μm ⁻¹ ] is preferably less than 1.65. Less than 50 is more preferred. A display device having a cured film (light-shielding film) with extremely excellent visibility as a black matrix by suppressing the reflectance in the light-shielding region where the light-shielding degree OD [μm ⁻¹ ] of the cured film with a thickness of 1 μm is higher. can be obtained.

In particular, the cured film obtained by curing the photosensitive resin composition of the present invention has a light shielding degree OD [μm ⁻¹ ] of a cured film with a thickness of 1 μm of 2.6 or more, and the reflectance [%] is the light shielding degree The value divided by OD is less than 1.65, the reflectance is 6.5% or less, and the light shielding degree OD [μm ⁻¹ ] of a cured film having a thickness of 1 μm is preferably 3.0 or more, and The value obtained by dividing the reflectance [%] by the light shielding degree OD is less than 1.50, and the reflectance is 5.0% or less, and more preferably the light shielding degree OD [μm ^-1 ] of a cured film having a thickness of 1 μm is 3. .3 or more, the value obtained by dividing the reflectance [%] by the light shielding degree OD is less than 1.50, and the reflectance is 5.0% or less.

Further, a color filter or touch panel having the cured film (light-shielding film) of the present invention as a black matrix is prepared by, for example, forming a cured film having a thickness of 1.0 to 2.0 μm on a transparent substrate, and obtaining a light-shielding film. After formation, red, blue, and green pixels are formed by photolithography, and red, blue, and green inks are injected into the light-shielding film by an inkjet process.

A cured film obtained by curing the photosensitive resin composition of the present invention can also be used as a black column spacer of a liquid crystal display device. For example, using a single black resist, a plurality of portions with different film thicknesses may be produced, one of which may function as a spacer and the other may function as a black matrix.

Each step of the method for forming a cured film by coating and drying the photosensitive resin composition will be specifically illustrated.

As a method for applying the photosensitive resin composition to the substrate, any method such as a method using a known solution dipping method, spray method, roller coater, land coater, slit coater or spinner can be adopted. can be done. By these methods, a film is formed by applying a desired thickness and then removing the solvent (pre-baking). Pre-baking is performed by heating with an oven, hot plate, etc., vacuum drying, or a combination thereof. The heating temperature and heating time in prebaking can be appropriately selected according to the solvent used, but, for example, it is preferably performed at 80 to 120° C. for 1 to 10 minutes.

As the radiation used for exposure, for example, visible light, ultraviolet rays, deep ultraviolet rays, electron beams, X-rays, etc. can be used, and the wavelength range of the radiation is preferably 250 to 450 nm. As a developer suitable for this alkali development, for example, an aqueous solution of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, tetramethylammonium hydroxide, or the like can be used. These developers can be appropriately selected according to the properties of the resin layer, and it is also effective to add a surfactant as necessary. The developing temperature is preferably 20 to 35° C., and a fine image can be precisely formed using a commercially available developing machine, ultrasonic cleaning machine, or the like. After alkali 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, or the like can be applied.

After development in this manner, 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. This is done by heating with an oven, hot plate or the like, similar to pre-baking. The patterned cured film (light-shielding film) of the present invention is formed through each step by photolithography. Then, polymerization or curing (both may be collectively referred to as curing) is completed by heat, and a light-shielding film having a desired pattern can be obtained. The curing temperature at this time is preferably 160 to 250°C.

As described above, the photosensitive resin composition of the present invention is suitable not only for forming fine patterns by operations such as exposure and alkali development, but also for forming patterns by conventional screen printing. A light-shielding film having excellent light-shielding properties, adhesion, electrical insulation, heat resistance, and chemical resistance can be obtained.

The photosensitive resin composition of the present invention can be suitably used as a coating material. In particular, color filter inks used in liquid crystal display devices or imaging devices, and light-shielding films formed therefrom, are useful as color filters, liquid crystal projections, black matrices for touch panels, and the like. In addition to color filter inks for color liquid crystal displays, the photosensitive resin composition of the present invention can also be used in various applications such as organic electroluminescence devices typified by organic EL devices, color liquid crystal display devices, color facsimiles, and image sensors. It can also be used as an ink material for color separation or light shielding in a color display. According to the color filter of the present invention, it is possible to reduce the reflection of external light at the interface between the colored layer (including the black resist layer) and the substrate, or, for example, the reflection of light emitted from the device when used in an organic EL device. can be done. That is, it is possible to improve the contrast in a bright place by reducing the reflection of external light, and to improve the luminous efficiency by improving the light extraction efficiency from the light emitting side.

EXAMPLES Hereinafter, embodiments of the present invention will be specifically described based on Examples and Comparative Examples, but the present invention is not limited to these.

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

[Solid content concentration]
A glass filter [weight: W0 (g)] was impregnated with 1 g of the resin solution obtained in Synthesis Example and weighed [W1 (g)], and the weight after heating at 160 ° C. for 2 hours [W2 (g) ] from the following formula.
Solid content concentration (% by weight) = 100 × (W2-W0) / (W1-W0)

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

[Molecular weight]
Gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation, solvent: tetrahydrofuran, column: TSKgelSuper H-2000 (2) + TSKgelSuper H-3000 (1) + TSKgelSuper H-4000 (1) + TSKgelSuper H-5000 (1 piece) (manufactured by Tosoh Corporation), temperature: 40 ° C., speed: 0.6 ml / min), standard polystyrene (manufactured by Tosoh Corporation, PS-oligomer kit) conversion value weight Average molecular weight (Mw) was determined.

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

Abbreviations used in Synthesis Examples and the like are as follows.
BPFE: A reaction product of 9,9-bis(4-hydroxyphenyl)fluorene and chloromethyloxirane. An epoxy compound represented by general formula (1), wherein X is a fluorene-9,9-diyl group, R ₁ to R ₄ are hydrogen, and l is 0 to 0.15.
DCPMA: dicyclopentanyl methacrylate GMA: glycidyl methacrylate St: styrene AA: acrylic acid BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride THPA: tetrahydrophthalic anhydride SA: succinic anhydride TEAB: Tetraethylammonium bromide AIBN: Azobisisobutyronitrile TDMAMP: Trisdimethylaminomethylphenol HQ: Hydroquinone TEA: Triethylamine TPGDA: Tripropylene glycol diacrylate PGMEA: Propylene glycol monomethyl ether acetate

[Synthesis Example A1]
BPFE (114.4 g, 0.23 mol), AA (33.2 g, 0.46 mol), PGMEA (157 g) and TEAB (0.48 g) were charged in a 500 ml four-necked flask equipped with a reflux condenser. , and 100 to 105° C. for 20 hours to react. Then, BPDA (35.3 g, 0.12 mol) and THPA (18.3 g, 0.12 mol) were charged into the flask, stirred at 120 to 125 ° C. for 6 hours, and the polymerizable unsaturated group-containing alkali-soluble resin was (A)-1 was obtained. The resulting resin solution had a solid content concentration of 56.1% by mass, an acid value (in terms of solid content) of 103 mgKOH/g, and an Mw of 3,600 by GPC analysis.

[Synthesis Example A2]
PGMEA (300 g) was placed in a 1 L four-necked flask equipped with a reflux condenser, and the inside of the flask system was replaced with nitrogen, and then the temperature was raised to 120°C. The monomer mixture (DCPMA (77.1 g, 0.35 mol), GMA (49.8 g, 0.35 mol), St (31.2 g, 0.30 mol), and AIBN (10 g) was then placed in the flask). The dissolved mixture was added dropwise from the dropping funnel over 2 hours, and further stirred at 120° C. for 2 hours to obtain a copolymer solution.

Then, after replacing the inside of the flask with air, AA (24.0 g, 0.33 mol (95% of the number of moles of GMA added)), TDMAMP (0.8 g) and HQ (0 .15 g) was added and stirred at 120° C. for 6 hours to obtain a polymerizable unsaturated group-containing copolymer solution. SA (30.0 g, 90% of the number of moles of AA added) and TEA (0.5 g) were added to the obtained polymerizable unsaturated group-containing copolymer solution and reacted at 120 ° C. for 4 hours, and the unsaturated group-containing alkali A soluble resin (A)-2 was obtained. The solid content concentration of the resin solution was 46.0% by mass, the acid value (in terms of solid content) was 76 mgKOH/g, and the Mw by GPC analysis was 5,300.

Also, a carbon black whose surface was coated with a dye was prepared by the following method.

[Preparation Example D1]
1000 g of carbon black (TPX-1099: manufactured by Cabot) was mixed with water to prepare 10 L of slurry, stirred at 95° C. for 1 hour, allowed to cool, and then washed with water. This was again mixed with water to prepare 10 L of slurry, 42.9 g of 70% nitric acid was added, and the mixture was stirred at 40° C. for 4 hours. After standing to cool and washing with water, the slurry was mixed with water again to prepare 10 L of slurry, 769.2 g of 13% sodium hypochlorite aqueous solution was added, and the mixture was stirred at 40° C. for 6 hours. After allowing to cool and washing with water, 10 L of slurry is prepared by mixing with water again, 38.1 g of a dye (Direct Deep BLACK) with a purity of 38.4% is added and stirred at 40 ° C. for 1 hour, and then further 10.1 g of aluminum sulfate was added and stirred at 40° C. for 1 hour. This was allowed to cool, washed with water, filtered and dried to obtain dye-coated carbon black.

The above dye-coated carbon black, polymer dispersant, dispersion resin (alkali-soluble resin ((A)-1) of Synthesis Example A1), and PGMEA are mixed and dispersed in a bead mill to obtain dye-coated carbon black. A carbon black dispersion (D)-1 having a concentration of 25.0% by mass, a polymer dispersant concentration of 2.0% by mass, and a dispersing resin concentration of 8.0% by mass was obtained.

The photosensitive resin compositions of Examples 1 to 7 and Comparative Examples 1 to 3 were prepared in the amounts shown in Table 1 (unit: parts by weight). The compounding ingredients used in Table 1 are as follows.

(Polymerizable unsaturated group-containing alkali-soluble resin)
(A)-1: Alkali-soluble resin solution obtained in Synthesis Example A1 (solid concentration: 56.1% by mass)
(A)-2: Alkali-soluble resin solution obtained in Synthesis Example A2 (solid concentration: 46.0% by mass)

(Photopolymerizable compound)
(B): A mixture of dipentaerythritol pentaacrylate and hexaacrylate (DPHA (acrylic equivalent 96-115), manufactured by Nippon Kayaku Co., Ltd.)

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

(Carbon black dispersion)
(D)-1: Dye-coated carbon black obtained in Preparation Example D1 concentration 25% by mass, polymer dispersant concentration 2% by mass, dispersion resin (alkali-soluble resin ((A)-1) of Synthesis Example A1) concentration 8 wt% PGMEA solvent pigment dispersion (35 wt% solids)
(D)-2: Pigment dispersion in a PGMEA solvent with a carbon black concentration of 25% by mass, a polymer dispersant concentration of 3% by mass, and a dispersing resin (alkali-soluble resin ((A)-1) of Synthesis Example A1) concentration of 5% by mass. Liquid (solid content 33% by mass)

(E)-1: Aluminum oxide TPGDA dispersion "ALTPGDA30WT%-A03" (manufactured by CIK Nanotech Co., Ltd., aluminum oxide concentration 30% by mass, TPGDA concentration 70% by mass, average particle size 90 nm)
(E)-2: Aluminum oxide TPGDA dispersion "ALTPGDA25WT%-A07" (manufactured by CIK Nanotech Co., Ltd., aluminum oxide concentration 25% by mass, TPGDA concentration 75% by mass, average particle size 50 nm)
(E)-3: Silica PGMEA dispersion "YA050C" (manufactured by Admatechs Co., Ltd., silica concentration 30% by mass, PGMEA concentration 70% by mass, average particle size 50 nm)

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

(Other components) -1: 3-Isocyanatopropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.)
(Other components)-2: 1 mass% ANON diluted solution of aralkyl-modified polymethylalkylsiloxane (BYK-323, manufactured by BYK-Chemie Japan Co., Ltd.)

[evaluation]
A cured film (light-shielding film) obtained by curing a photosensitive resin composition for use in evaluation was prepared as follows.

(Preparation of cured film (coating film) for optical density (OD) evaluation)
A 125 mm × 125 mm glass substrate "#1737" (manufactured by Corning Incorporated) was previously irradiated with ultraviolet light having a wavelength of 254 nm and an illuminance of 1000 mJ/cm ² with a low-pressure mercury lamp to wash the surface of the photosensitive resin composition shown in Table 1. (Hereinafter referred to as "glass substrate"), it is coated using a spin coater so that the film thickness after heat curing treatment is 1.2 μm, and pre-baked at 90 ° C. for 1 minute using a hot plate to form a cured film. (Coating film) was produced. A photo-curing reaction was performed by irradiating 50 mJ/cm ² of ultraviolet rays from an ultra-high pressure mercury lamp with an i-line illuminance of 30 mW/cm ² without covering with a negative photomask.

Next, the exposed cured film (light-shielding film) is exposed to a 0.05% potassium hydroxide solution at 25° C. under a shower pressure of 1 kgf/cm ² for 20 seconds from the developing time (break time=BT) when the pattern begins to appear. After the development treatment, the cured film (light-shielding film) was washed with water spray of 5 kgf/cm ² to remove the unexposed portion of the cured film (light-shielding film) to form a cured film pattern on the glass substrate. C. for 30 minutes to obtain cured films (light-shielding films) according to Examples 1 to 7 and Comparative Examples 1 to 3.

[Film thickness measurement]
(Evaluation method)
Using a step meter ("Tencor P-17" manufactured by KLA-Tencor), the step between the glass substrate surface and the cured film surface was measured under the conditions of a measurement range of 500 µm, a scanning speed of 50 µm/sec, and a sampling rate of 20 Hz. The average value was defined as the average thickness of the cured film.

[Optical density (OD) evaluation]
(Evaluation method)
The optical density (OD) was measured using a transmission densitometer “X-rite 361T (V)” manufactured by X-rite. The optical density (OD) per 1 μm of film thickness was calculated from the measured film thickness and optical density (OD).

The optical density (OD) was calculated by the following formula (5).
Optical Density (OD) = -log ₁₀ T Equation (5)
(T indicates transmittance)

[Reflectance evaluation]
(Evaluation method)
Ultraviolet visible infrared spectrophotometer "UH4150" (manufactured by Hitachi High-Tech Science Co., Ltd.) is applied to a substrate with a cured film (light-shielding film) prepared in the same manner as the cured film (light-shielding film) for optical density (OD) evaluation. was used to measure the reflectance of each of the cured film (light shielding film) side and the substrate (glass substrate) side under the conditions of a C light source, an incident angle of 2°, and a wavelength range of 380 to 780 nm.

(Preparation of cured film (light shielding film) for evaluation of development characteristics)
A 125 mm × 125 mm glass substrate "#1737" (manufactured by Corning Incorporated) was previously irradiated with ultraviolet light having a wavelength of 254 nm and an illuminance of 1000 mJ/cm ² with a low-pressure mercury lamp to wash the surface of the photosensitive resin composition shown in Table 1. (Hereinafter referred to as “glass substrate”), it is coated using a spin coater so that the film thickness after heat curing treatment is 1.2 μm, and prebaked at 90° C. for 1 minute using a hot plate to harden the film. (Light shielding film) was produced. 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 dry cured film, and an ultra-high pressure mercury lamp with an i-line illuminance of 30 mW/cm ² was used to expose the ultraviolet rays to 50 mJ/cm ² . was irradiated to carry out a photo-curing reaction of the photosensitive area.

Next, the exposed cured film (light-shielding film) was exposed to a 0.04% potassium hydroxide solution at 25° C. under a shower pressure of 1 kgf/cm ² for +20 seconds from the developing time (break time=BT) at which the pattern began to appear. After the development treatment, the cured film (light-shielding film) was washed with water spray of 5 kgf/cm ² , and the unexposed portion of the cured film (light-shielding film) was removed to form a cured film pattern on the glass substrate. C. for 30 minutes for main curing (post-baking) to obtain cured films (light-shielding films) according to Examples 1 to 7 and Comparative Examples 1 to 3.

The cured films (light-shielding films) obtained by curing the photosensitive resin compositions of Examples 1 to 7 and Comparative Examples 1 to 3 obtained above were evaluated for the following items.

[Evaluation of development characteristics]
(pattern linearity)
(Evaluation method)
A 10 μm mask pattern of the main curing (post-baking) was observed using an optical microscope. The evaluation of pattern linearity was performed in the case of BT+20 seconds. In addition, △ or more was taken as the pass.

(Evaluation Criteria for Development Properties)
◯: When the pattern length is taken as 100%, projections of 0.5 μm are observed at less than 1% with respect to a line width of 10 μm. △: Jagged pattern edges However, when the length of the pattern is taken as 100%, protrusions of 0.5 μm are observed at a rate of 1% or more and less than 25% with respect to a line width of 10 μm. When the length is taken as 100%, protrusions of 0.5 μm are observed at a rate of 25% or more for a line width of 10 μm.

Table 2 shows the above evaluation results.

It was confirmed that the photosensitive resin compositions of Examples 1 to 7 can reduce the reflectance from the substrate side at a high light shielding rate compared to the systems using silica particles (Comparative Examples 1 to 3). It was also confirmed that the cured films (light-shielding films) obtained by curing the photosensitive resin compositions of Examples 1 to 3 and 5 all had good pattern linearity.

According to the photosensitive resin composition of the present invention, it is possible to provide a photosensitive resin composition that achieves both high light shielding properties and low reflectance, a cured film, a color filter, and a touch panel using the same. Moreover, according to this color filter and touch panel, various display devices with excellent visibility can be provided.

Claims (9)

(A) an unsaturated group-containing alkali-soluble resin;
(B) a photopolymerizable compound having at least two unsaturated bonds;
(C) a photoinitiator;
(D) at least one light-shielding component selected from the group consisting of black pigments, mixed-color organic pigments, and light-shielding materials;
(E) fine particles having a refractive index of 1.50 to 1.80;
A photosensitive resin composition comprising: 2. The photosensitive resin composition according to claim 1, wherein the (E) fine particles are aluminum oxide particles. 2. The photosensitive resin composition according to claim 1, wherein the fine particles (E) have an average particle size of 10 to 300 nm. 2. The photosensitive resin composition according to claim 1, wherein the proportion of the (E) fine particles in the solid content is 1 to 30% by mass. A cured film having a thickness of 1 μm obtained by curing the photosensitive resin composition with light has a light shielding degree OD [μm ⁻¹ ] of 2.6 or more, and a reflectance [%] of the cured film of 6.5. 5 or less, and the value obtained by dividing the reflectance of the cured film by the light shielding degree OD is less than 1.65. A cured film obtained by curing the photosensitive resin composition according to any one of claims 1 to 5. A color filter comprising the cured film according to claim 6 as a black matrix. A touch panel having the cured film according to claim 6 as a black matrix. A display device comprising the color filter according to claim 7 or the touch panel according to claim 8.