Photosensitive resin composition, cured film, substrate with cured film, method for producing substrate with cured film and display device

Abstract

To provide a photosensitive resin composition capable of forming a cured film having a light scattering function directly on the substrate regardless of the heat resistance temperature of a substrate.SOLUTION: There is provided a photosensitive resin composition which comprises (A) an alkali-soluble resin containing an unsaturated group, (B) a photopolymerizable monomer having at least two ethylenic unsaturated bonds, (C) metal oxide particles having an average particle diameter of 40 nm or more and 600 nm or less and a refractive index of 1.2 or more and 1.5 or less or resin particles and (D) a photopolymerization initiator. The content of the component (D) is 10 mass% or more and 70 mass% or less based on the total mass of the solid content.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a photosensitive resin composition, a cured film obtained by curing the photosensitive resin composition, a substrate with a cured film, a method for producing a substrate with a cured film, and a display device having the cured film or the substrate with a cured film. [Background technology]

[0002] In recent years, studies have been conducted to form patterns using photosensitive resin compositions with light-scattering properties not only on highly heat-resistant substrates such as glass substrates and silicon wafers that can be used at high temperatures of 200°C or higher, but also on plastic substrates (plastic films, resin films) such as PET (polyethylene terephthalate) and PEN (polyethylene naphthalate), which have low heat resistance, or on substrates with organic devices such as organic electroluminescence devices and organic TFTs, with the aim of making devices more flexible and single-chip.

[0003] However, when a photosensitive resin composition having a light-scattering function for forming a pattern by high-temperature baking is used to form a pattern by low-temperature baking in accordance with the heat resistance of a substrate such as a plastic substrate or a substrate with an organic device, the film strength of the pattern formed on the substrate is insufficient, and there are problems such as film thinning of the coating film, surface roughness, pattern peeling, etc., which are likely to occur in subsequent processes (e.g., solvent resistance during resist coating, alkali resistance during alkali development, etc.). Therefore, there is a demand for a photosensitive resin composition having a light-scattering property that can be used for both high-temperature and low-temperature baking.

[0004] In recent years, photosensitive resin compositions having a light-scattering function have been required to satisfy a variety of requirements regarding optical properties, such as the combination of light transmittance or haze and light scattering intensity, etc. Furthermore, in the development of new display devices, there is a demand for greater design freedom for display devices by applying a light-scattering layer having a specific function to improve functionality such as power saving and an expanded color gamut.

[0005] For example, Patent Document 1 discloses a photosensitive composition for forming a pattern having a light-scattering function, which is composed of a TiO2 filler, a photopolymerizable monomer, an alkali-soluble resin, a photopolymerization initiator, and an organic solvent. The photosensitive composition is said to have photolithography properties suitable for use in display devices, and also has light-scattering properties in which the TiO2 filler scatters blue light at angles wider than the incident angle.

[0006] Patent Document 2 discloses a resin composition for a light-scattering layer, which contains at least one resin (A) as a binder material, fluorine-containing light-scattering particles (B), and at least one metal oxide fine particle selected from the group consisting of ZrO2 and TiO2 as metal oxide fine particles (C). The resin composition for a light-scattering layer is said to have small wavelength dependency of light extraction efficiency and can be used over a wide wavelength range. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-156304 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-022794 Summary of the Invention [Problem to be solved by the invention]

[0008] However, according to the findings of the present inventors, the photosensitive composition described in Patent Document 1 has low solvent resistance, and the resin composition for a light-scattering layer described in Patent Document 2 could not obtain a cured film pattern having the desired optical properties (transmittance, light scattering property). Furthermore, the photosensitive composition described in Patent Document 1 and the resin composition for a light-scattering layer described in Patent Document 2 did not fully satisfy the desired development properties of the cured film (adhesion, linearity, definition).

[0009] Conventionally, in order to impart light scattering properties to cured films, metal oxide particles with a relatively high refractive index of 1.9 or more have often been used. However, as diverse requirements for optical properties such as light transmittance or the combination of haze and light scattering intensity are becoming more prevalent, there is a demand for photosensitive resin compositions that can satisfy the required optical properties and other cured film properties even when using metal oxide particles or resin particles with a refractive index of 1.2 or more and 1.5 or less.

[0010] Furthermore, in the development of new display devices, there is a demand for photosensitive resin compositions that can be applied to light-scattering layers that intensify diffuse transmitted light in order to improve the light extraction efficiency of light-emitting elements such as organic EL devices, and that can be applied to light-scattering layers that intensify diffuse reflected light in display devices that utilize light wavelength conversion of light-emitting elements.

[0011] The present invention has been made in view of the above points, and aims to provide a photosensitive resin composition capable of forming a cured film having good optical properties and good development properties regardless of the heat resistance temperature of the substrate, a cured film obtained by curing the photosensitive resin composition, a substrate with a cured film, a method for manufacturing a substrate with a cured film, and a display device having the cured film and the substrate with a cured film. [Means for solving the problem]

[0012] The photosensitive resin composition of the present invention comprises (A) an unsaturated group-containing alkali-soluble resin, (B) a photopolymerizable monomer having at least two ethylenically unsaturated bonds, (C) metal oxide particles or resin particles having an average particle diameter of 40 nm or more and 600 nm or less and a refractive index of 1.2 or more and 1.5 or less, and (D) a photopolymerization initiator, and the content of the component (C) is 10 mass % or more and 70 mass % or less based on the total mass of the solid content.

[0013] The cured film of the present invention is obtained by curing the above-described photosensitive resin composition.

[0014] The substrate with a cured film of the present invention has the above-described cured film.

[0015] The display device of the present invention has the cured film or the substrate with the cured film.

[0016] The method for producing a cured film-coated substrate of the present invention is a method for producing a cured film-coated substrate by forming a cured film pattern having light-scattering properties on a substrate having a heat resistance temperature of 150°C or less, in which the photosensitive resin composition is applied to the substrate, exposed to light through a photomask, and developed to remove unexposed areas, and then heated at 150°C or less to form a predetermined cured film pattern.

[0017] Another method for producing a cured film-coated substrate of the present invention is a method for producing a cured film-coated substrate by forming a cured film pattern having light-scattering properties on a substrate having a heat resistance temperature of more than 150°C, in which the photosensitive resin composition is applied to the substrate, exposed to light through a photomask, and developed to remove unexposed areas, and then heated at more than 150°C to form a predetermined resin film pattern. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a photosensitive resin composition capable of forming a cured film having good optical properties and good development properties regardless of the heat resistance temperature of the substrate, a cured film obtained by curing the photosensitive resin composition, a substrate with a cured film, a method for producing a substrate with a cured film, and a display device having the cured film and the substrate with a cured film.

[0019] As a result, in the past, in order to impart light scattering function, metal oxide particles having a relatively high refractive index of 1.9 or more and a relatively large particle size have often been used. However, as diverse requirements regarding optical properties such as light transmittance or the combination of haze and light scattering intensity are becoming more common, it is possible to provide a photosensitive resin composition that can satisfy the required optical properties and other cured film properties even when using metal oxide or resin particles having a refractive index of 1.2 or more and 1.5 or less.

[0020] Furthermore, the present invention can provide a photosensitive resin composition that can be applied to a light-scattering layer that intensifies diffuse transmitted light in order to improve the light extraction efficiency of light-emitting elements such as organic EL elements in the development of new display devices, and that can be applied to a light-scattering layer that intensifies diffuse reflected light in display devices that utilize light wavelength conversion of light-emitting elements. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. In the present invention, when the first decimal place of the content of each component is 0, the notation after the decimal point may be omitted.

[0022] 1. Photosensitive resin composition A photosensitive resin composition according to one embodiment of the present invention includes (A) an unsaturated group-containing alkali-soluble resin, (B) a photopolymerizable monomer having at least two ethylenically unsaturated bonds, (C) metal oxide particles or resin particles having an average particle diameter of 40 nm or more and 600 nm or less and a refractive index of 1.2 or more and 1.5 or less, and (D) a photopolymerization initiator.

[0023] [Component (A)] The unsaturated group-containing alkali-soluble resin (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 carboxyl group. Any of the above resins can be used without any particular limitation.

[0024] From the viewpoint of improving adhesion to the substrate, the component (A) is preferably an unsaturated group-containing alkali-soluble resin (hereinafter simply referred to as "alkali-soluble resin") represented by the following general formula (1).

[0025] [ka] (In formula (1), R1, R2, R3, and R4 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a halogen atom, or a phenyl group; R5 represents a hydrogen atom or a methyl group; X represents -CO-, -SO2-, -C(CF3)2-, -Si(CH3)2-, -CH2-, -C(CH3)2-, -O-, a fluorene-9,9-diyl group, or a direct bond; Y represents a tetravalent carboxylic acid residue; Z represents each independently a hydrogen atom or a substituent represented by general formula (2), and at least one Z represents a substituent represented by general formula (2); and n has an average value of 1 to 20.)

[0026] [ka] (In formula (2), W is a divalent or trivalent carboxylic acid residue, and m is 1 or 2.)

[0027] Next, a method for producing the alkali-soluble resin represented by the above general formula (1) will be described in detail.

[0028] First, an epoxy compound (a-1) having two epoxy groups per molecule, represented by general formula (3) (hereinafter simply referred to as "epoxy compound (a-1)"), is reacted with an unsaturated group-containing monocarboxylic acid (e.g., (meth)acrylic acid) to obtain an epoxy (meth)acrylate. Note that "(meth)acrylic acid" is a general term for acrylic acid and methacrylic acid, and "(meth)acryloyl group" is a general term for acryloyl group and methacryloyl group, and refers to either or both of these.

[0029] [ka] (In formula (3), R1, R2, R3, and R4 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a halogen atom, or a phenyl group, and X represents -CO-, -SO2-, -C(CF3)2-, -Si(CH3)2-, -CH2-, -C(CH3)2-, -O-, a fluorene-9,9-diyl group, or a direct bond.)

[0030] The epoxy compound (a-1) is an epoxy compound having two glycidyl ether groups, which is obtained by reacting a bisphenol with epichlorohydrin.

[0031] Examples of the bisphenols 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, and the like.Among these, from the viewpoint of further enhancing adhesion, bisphenols having a fluorene-9,9-diyl group are preferred. These may be used alone or in combination of two or more.

[0032] Examples of the unsaturated group-containing monocarboxylic acid compound include acrylic acid, methacrylic acid, and compounds obtained by reacting acrylic acid or methacrylic acid with an acid monoanhydride such as succinic anhydride, maleic anhydride, or phthalic anhydride.

[0033] The reaction of the epoxy compound (a-1) with (meth)acrylic acid can be carried out by a known method. For example, Japanese Patent Application Laid-Open No. 4-355450 discloses that a diol compound containing a polymerizable unsaturated group can be obtained by using about 2 moles of (meth)acrylic acid per mole of an epoxy compound having two epoxy groups. In the present invention, the compound obtained by the above reaction is a diol compound containing a polymerizable unsaturated group, and is a diol (d) containing a polymerizable unsaturated group represented by general formula (4) (hereinafter, also simply referred to as "diol (d) represented by general formula (4)").

[0034] [ka] (In formula (4), R1, R2, R3, and R4 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a halogen atom, or a phenyl group; R5 represents a hydrogen atom or a methyl group; and X represents -CO-, -SO2-, -C(CF3)2-, -Si(CH3)2-, -CH2-, -C(CH3)2-, -O-, a fluorene-9,9-diyl group, or a direct bond.)

[0035] In the production of the alkali-soluble resin represented by general formula (1) by synthesizing the diol (d) represented by general formula (4), followed by the addition reaction of a polycarboxylic acid or its anhydride, and then reacting with a monofunctional epoxy compound or the like having a polymerizable unsaturated group reactive with a carboxy group, the reaction is usually carried out in a solvent using a catalyst as necessary.

[0036] Examples of the solvent include cellosolve-based solvents such as ethyl cellosolve acetate and butyl cellosolve acetate; high-boiling ether or ester-based solvents such as diglyme, ethyl carbitol acetate, butyl carbitol acetate and propylene glycol monomethyl ether acetate; and ketone-based solvents such as cyclohexanone and diisobutyl ketone. The reaction conditions, such as the solvent and catalyst used, are not particularly limited, but it is preferable to use, for example, a solvent that does not have a hydroxyl group and has a boiling point higher than the reaction temperature as the reaction solvent.

[0037] Furthermore, it is preferable to use a catalyst in the reaction between a carboxy group and an epoxy group. For example, Japanese Patent Application Laid-Open No. 9-325494 describes ammonium salts such as tetraethylammonium bromide and triethylbenzylammonium chloride, and phosphines such as triphenylphosphine and tris(2,6-dimethoxyphenyl)phosphine.

[0038] Next, the diol (d) represented by general formula (4), obtained by the reaction of the epoxy compound (a-1) with (meth)acrylic acid, is reacted with a dicarboxylic acid or tricarboxylic acid or its acid anhydride (b), and a tetracarboxylic acid or its acid dianhydride (c), to obtain an alkali-soluble resin represented by general formula (1) having a carboxy group and a polymerizable unsaturated group in one molecule.

[0039] [ka] (In formula (1), R1, R2, R3, and R4 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a halogen atom, or a phenyl group; R5 represents a hydrogen atom or a methyl group; X represents -CO-, -SO2-, -C(CF3)2-, -Si(CH3)2-, -CH2-, -C(CH3)2-, -O-, a fluorene-9,9-diyl group, or a direct bond; Y represents a tetravalent carboxylic acid residue; Z represents each independently a hydrogen atom or a substituent represented by general formula (2), and at least one Z represents a substituent represented by general formula (2); and n has an average value of 1 to 20.)

[0040] [ka] (In formula (2), W is a divalent or trivalent carboxylic acid residue, and m is 1 or 2.)

[0041] The acid component used to synthesize the alkali-soluble resin represented by general formula (1) is a polyvalent acid component capable of reacting with the hydroxyl group in the diol (d) molecule represented by general formula (4). It is necessary to use a dicarboxylic acid or tricarboxylic acid or its monoanhydride (b) in combination with a tetracarboxylic acid or its dianhydride (c). The carboxylic acid residue of the acid component may be either a saturated or unsaturated hydrocarbon group. Furthermore, these carboxylic acid residues may contain bonds containing heteroatoms such as -O-, -S-, or carbonyl groups.

[0042] As the dicarboxylic acid or tricarboxylic acid or their acid monoanhydrides (b), chain hydrocarbon dicarboxylic acids or tricarboxylic acids, alicyclic hydrocarbon dicarboxylic acids or tricarboxylic acids, aromatic hydrocarbon dicarboxylic acids or tricarboxylic acids, or their acid monoanhydrides, etc. can be used.

[0043] Examples of the acid monoanhydrides of the 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, diglycolic acid, etc., and acid monoanhydrides of dicarboxylic acids or tricarboxylic acids into which any substituent has been introduced.

[0044] Examples of the acid monoanhydrides of alicyclic hydrocarbon dicarboxylic acids or tricarboxylic acids include acid monoanhydrides of cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, methyl-3,6-endomethylenetetrahydrophthalic acid, norbornanedicarboxylic acid, chlorendic acid, hexahydrotrimellitic acid, and the like, as well as acid monoanhydrides of dicarboxylic acids or tricarboxylic acids into which any substituent has been introduced.

[0045] Examples of the acid monoanhydrides of aromatic dicarboxylic acids or tricarboxylic acids include acid monoanhydrides of phthalic acid, isophthalic acid, trimellitic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, etc., and acid monoanhydrides of dicarboxylic acids or tricarboxylic acids into which any substituent has been introduced.

[0046] Among the acid monoanhydrides of dicarboxylic acids or tricarboxylic acids, succinic acid, itaconic acid, tetrahydrophthalic acid, hexahydrotrimellitic acid, phthalic acid, and trimellitic acid are preferred, and succinic acid, itaconic acid, and tetrahydrophthalic acid are more preferred.Furthermore, it is preferred to use the acid monoanhydrides of dicarboxylic acids or tricarboxylic acids.The above-mentioned acid monoanhydrides of dicarboxylic acids or tricarboxylic acids may be used alone or in combination of two or more.

[0047] As the tetracarboxylic acid or its acid dianhydride (c), a chain hydrocarbon tetracarboxylic acid, an alicyclic hydrocarbon tetracarboxylic acid, an aromatic hydrocarbon tetracarboxylic acid, or an acid dianhydride thereof can be used.

[0048] Examples of the chain hydrocarbon tetracarboxylic acid include butane tetracarboxylic acid, pentane tetracarboxylic acid, hexane tetracarboxylic acid, and chain hydrocarbon tetracarboxylic acids into which a substituent such as an alicyclic hydrocarbon group or an unsaturated hydrocarbon group has been introduced.

[0049] Examples of the alicyclic tetracarboxylic acid include cyclobutane tetracarboxylic acid, cyclopentane tetracarboxylic acid, cyclohexane tetracarboxylic acid, cycloheptane tetracarboxylic acid, norbornane tetracarboxylic acid, and alicyclic tetracarboxylic acids having a substituent such as a chain hydrocarbon group or an unsaturated hydrocarbon group introduced therein.

[0050] Examples of aromatic tetracarboxylic acids include pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, diphenyl ether tetracarboxylic acid, diphenyl sulfone tetracarboxylic acid, naphthalene-1,4,5,8-tetracarboxylic acid, and naphthalene-2,3,6,7-tetracarboxylic acid.

[0051] Among the tetracarboxylic acids or acid dianhydrides thereof, biphenyltetracarboxylic acid, benzophenonetetracarboxylic acid, and diphenylethertetracarboxylic acid are preferred, and biphenyltetracarboxylic acid and diphenylethertetracarboxylic acid are more preferred. Furthermore, among the tetracarboxylic acids or acid dianhydrides thereof, it is preferred to use the acid dianhydrides thereof. The above-mentioned tetracarboxylic acids or acid dianhydrides thereof may be used alone or in combination of two or more.

[0052] The reaction of the diol (d) represented by the general formula (4) with the acid components (b) and (c) is not particularly limited, and any known method can be used. For example, Japanese Patent Application Laid-Open No. 9-325494 describes a method in which an epoxy (meth)acrylate is reacted with a tetracarboxylic dianhydride at a reaction temperature of 90 to 140°C.

[0053] Here, it is preferable to react the diol (d) represented by general formula (4), dicarboxylic acid or tricarboxylic acid or their acid monoanhydride (b), and tetracarboxylic acid dianhydride (c) in a molar ratio of (d):(b):(c)=1:0.01-1.0:0.2-1.0 so that the terminal of the compound becomes a carboxy group.

[0054] For example, when (b) acid monoanhydride and (c) acid dianhydride are used, the molar ratio of the amount of acid component [(b) / 2 + (c)] to the diol (d) represented by general formula (4) is preferably 0.5 to 1.0. If the molar ratio exceeds 0.5, the terminal of the alkali-soluble resin represented by general formula (1) is not converted to an acid anhydride, thereby preventing an increase in the content of unreacted acid dianhydride, thereby improving the stability of the alkali-soluble resin composition over time. If the molar ratio is 1.0 or less, the content of unreacted diol compounds containing polymerizable unsaturated groups is not increased, thereby improving the stability of the alkali-soluble resin composition over time. The molar ratios of the components (d), (b), and (c) can be varied within the above-mentioned ranges to adjust the acid value and molecular weight of the alkali-soluble resin represented by general formula (1).

[0055] The acid value of the alkali-soluble resin represented by general formula (1) is preferably in the range of 20 mgKOH / g to 180 mgKOH / g, more preferably 40 mgKOH / g to 140 mgKOH / g, and even more preferably 80 mgKOH / g to 120 mgKOH / g. When the acid value is 20 mgKOH / g or more, residues are less likely to remain during alkaline development. When the acid value is 180 mgKOH / g or less, penetration of the alkaline developer is prevented from becoming too rapid, thereby suppressing peeling development. The acid value can be determined, for example, by titration with a 1 / 10 N aqueous KOH solution using a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.).

[0056] The weight-average molecular weight (Mw) of the alkali-soluble resin represented by general formula (1) is preferably 1,000 to 100,000, more preferably 2,000 to 20,000, and even more preferably 2,000 to 6,000. When the weight-average molecular weight is 1,000 or more, it is possible to suppress a decrease in pattern adhesion during alkaline development. When the weight-average molecular weight is 100,000 or less, it is easy to adjust the solution viscosity of the photosensitive resin composition to a level suitable for application, and alkaline development does not require excessive time. The weight-average molecular weight (Mw) can be determined in terms of polystyrene using, for example, gel permeation chromatography (GPC) measurement (HLC-8220GPC, manufactured by Tosoh Corporation).

[0057] Another example of a resin suitable for component (A) is a copolymer of (meth)acrylic acid, a (meth)acrylic acid ester, etc., and includes a resin having a (meth)acryloyl group and a carboxy group. Examples of the resin include an unsaturated group-containing alkali-soluble resin obtained by copolymerizing a (meth)acrylic acid ester containing glycidyl (meth)acrylate in a solvent to obtain a copolymer, reacting the copolymer with (meth)acrylic acid, and finally reacting the copolymer with an anhydride of a dicarboxylic acid or tricarboxylic acid. Examples of the copolymer include a copolymer disclosed in Japanese Patent Application Laid-Open No. 2014-111722, which is composed of 20 to 90 mol% of repeating units derived from diester glycerol in which the 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 which has a number average molecular weight (Mn) of 2,000 to 20,000 and an acid value of 35 to 120 mgKOH / g; and an unsaturated group-containing alkali-soluble resin disclosed in Japanese Patent Application Laid-Open No. 2018-141968, which is a polymer containing units derived from (meth)acrylic acid ester compounds and units having (meth)acryloyl groups and di- or tricarboxylic acid residues, and which has a weight average molecular weight (Mw) of 3,000 to 50,000 and an acid value of 30 to 200 mgKOH / g.

[0058] The unsaturated group-containing alkali-soluble resin of the component (A) may be used alone or in combination of two or more types.

[0059] Among these resins, resins with highly aromatic skeletons generally tend to have a higher specific gravity than aliphatic resins, allowing for a higher specific gravity of the resin solution when the resin concentration is the same. This is thought to improve the dispersion stability of metal oxide particles, which have a higher specific gravity than the resin. Therefore, the use of an alkali-soluble resin represented by general formula (1) can produce a photosensitive resin composition with sufficient dispersion stability for metal oxide particles. In particular, the use of an unsaturated-group-containing alkali-soluble resin (cardo resin) in which X in general formula (1) has a polycyclic aromatic skeleton, such as a fluorene-9,9-diyl group, enhances this effect, further improving the dispersion stability of metal oxide particles. The inclusion of a cardo resin as component (A) in the photosensitive resin composition of the present invention can improve the light scattering properties of the cured product obtained by curing the photosensitive resin composition. Furthermore, cardo resins have excellent adhesion properties during development when forming patterns by photolithography. This property is thought to be effectively utilized even when inorganic fillers, such as metal oxides, are coexisting.

[0060] The content of the component (A) is preferably 25% by mass or more and 70% by mass or less based on the total mass of the solid content.

[0061] When the photosensitive resin composition of the present invention is a composition that is baked at a low temperature of 150°C or less, the content of component (A) is preferably 25% by mass to 60% by mass, based on the total mass of the solids. When a cardo resin is used as component (A), the content is preferably 30% by mass to 55% by mass. Furthermore, when other resins such as acrylic copolymers are used as component (A), the content is preferably 25% by mass to 50% by mass. When the content of component (A) is 25% by mass or more, good developability can be obtained, even when metal oxide particles or resin particles with a refractive index of 1.2 to 1.5 are contained, making it possible to obtain the desired pattern without residue. When the content of component (A) is 60% by mass or less, the suitability of the production process during alkaline development is improved and sufficient photocurability can be ensured.

[0062] Furthermore, when the photosensitive resin composition of the present invention is a composition that is baked at a high temperature exceeding 150°C, the content of component (A) is preferably 40% by mass or more and 70% by mass or less, based on the total mass of the solid content. Furthermore, when a cardo resin is used as component (A), the content is preferably 45% by mass or more and 60% by mass or less. Furthermore, when other resins such as acrylic copolymers are used as component (A), the content is preferably 40% by mass or more and 60% by mass or less. When the content of component (A) is 40% by mass or more, good developability can be obtained, even when metal oxide particles or resin particles with a refractive index of 1.2 to 1.5 are contained, allowing the desired pattern to be obtained without residue. When the content of component (A) is 70% by mass or less, the production process suitability during alkaline development is improved and sufficient photocurability can be ensured.

[0063] Next, the components (B) to (F) contained in the photosensitive resin composition according to one embodiment of the present invention will be described.

[0064] [(B) Component] Component (B) is a photopolymerizable monomer containing at least two ethylenically unsaturated bonds. Component (B) can improve the adhesion of the cured product and also provide good development characteristics (pattern adhesion, pattern linearity, and pattern definition) in the exposed area.

[0065] Examples of component (B) include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tetramethylene glycol di(meth)acrylate, glycerol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol di(meth)acrylate, penta ... Examples of the ethylene double bond-containing compound include (meth)acrylic acid esters such as erythritol 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)acryloyl group as the ethylene double bond-containing compound. These may be used alone or in combination of two or more.

[0066] Examples of the dendritic polymer include those obtained by adding a polyvalent mercapto compound to part of the carbon-carbon double bonds in the (meth)acryloyl group of a polyfunctional (meth)acrylate. Specifically, they include dendritic polymers obtained by reacting the (meth)acryloyl group of a polyfunctional (meth)acrylate represented by general formula (5) with the thiol group of a polyvalent mercapto compound represented by general formula (6).

[0067] [ka] (In formula (5), R6 is a hydrogen atom or a methyl group, and R7 is R9(OH) k The remaining portion is obtained by donating l hydroxyl groups out of k hydroxyl groups to the ester bond in the formula. Preferred R9(OH) kis a polyhydric alcohol based on a non-aromatic straight-chain or branched-chain hydrocarbon skeleton having 2 to 8 carbon atoms, a polyhydric alcohol ether formed by linking multiple molecules of the polyhydric alcohol via 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 l are independently integers of 2 to 20, and k≧l.

[0068] [ka] (In formula (6), R8 is a single bond or a divalent to hexavalent C1 to C6 hydrocarbon group, and p is 2 when R8 is a single bond, and is an integer from 2 to 6 when R8 is a divalent to hexavalent group.)

[0069] Examples of polyfunctional (meth)acrylates represented by general formula (5) 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, trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol octa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, caprolactone, Examples of (meth)acrylic acid esters include acrylate-modified pentaerythritol tri(meth)acrylate, caprolactone-modified pentaerythritol tetra(meth)acrylate, caprolactone-modified dipentaerythritol hexa(meth)acrylate, epichlorohydrin-modified hexahydrophthalic acid di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide-modified neopentyl glycol di(meth)acrylate, propylene oxide-modified neopentyl glycol di(meth)acrylate, trimethylolpropane benzoate (meth)acrylate, tris((meth)acryloxyethyl)isocyanurate, alkoxy-modified trimethylolpropane tri(meth)acrylate, dipentaerythritol poly(meth)acrylate, alkyl-modified dipentaerythritol tri(meth)acrylate, and ditrimethylolpropane tetra(meth)acrylate. These compounds may be used alone or in combination of two or more.

[0070] Examples of polyvalent mercapto compounds represented by general formula (6) include 1,2-dimercaptoethane, 1,3-dimercaptopropane, 1,4-dimercaptobutane, bisdimercaptoethanethiol, 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.

[0071] In addition, a polymerization inhibitor may be added as needed during the synthesis of the dendritic polymer. Examples of polymerization inhibitors include hydroquinone compounds and phenolic compounds. Specific examples of these include hydroquinone, methoxyhydroquinone, catechol, p-tert-butylcatechol, cresol, dibutylhydroxytoluene, and 2,4,6-tri-tert-butylphenol (BHT).

[0072] Component (B) can crosslink molecules of the unsaturated group-containing alkali-soluble resin, and to achieve this function, it is preferable to use one having three or more unsaturated bonds. Furthermore, the acrylic equivalent, calculated by dividing the molecular weight of the monomer by the number of (meth)acryloyl groups in one molecule, is preferably 50 g / eq or more and 300 g / eq or less, and more preferably 80 g / eq or more and 200 g / eq or less. Component (B) does not have a free carboxy group.

[0073] The content of the component (B) is preferably 10% by mass or more and 40% by mass or less based on the total mass of the solid content.

[0074] When the photosensitive resin composition of the present invention is a composition that is baked at a low temperature of 150°C or less, the content of component (B) is preferably 10% by mass or more and 40% by mass or less based on the total mass of the solid content. When a cardo resin is used as component (A), the content of component (B) is preferably 10% by mass or more and 30% by mass or less. When other acrylic copolymer resins or the like are used as component (A), the content of component (B) is preferably 10% by mass or more and 35% by mass or less.

[0075] Furthermore, when the photosensitive resin composition of the present invention is a composition that is baked at a high temperature above 150°C, the content of component (B) is preferably 10% by mass or more and 40% by mass or less, based on the total mass of the solid content. Here, when a cardo resin is used as component (A), the content of component (B) is preferably 10% by mass or more and 30% by mass or less. When other acrylic copolymer-based resins are used as component (A), the content of component (B) is preferably 10% by mass or more and 35% by mass or less.

[0076] When the content of component (B) is 10% by mass or more, based on the total mass of solids, the cured product is less likely to become brittle, and when it is 40% by mass or less, a decrease in the acid value of the composition is suppressed, increasing the solubility of the unexposed areas in an alkaline developer, thereby improving the pattern adhesion, pattern linearity, and pattern definition of the cured product.

[0077] [(C) component] Component (C) is a metal oxide particle or resin particle having an average particle diameter of 40 nm to 600 nm and a refractive index of 1.2 to 1.5. The inclusion of component (C) imparts light scattering properties to the cured film (coating film). In this specification, "metal oxide" refers to oxides of metals and semimetals, as well as composite oxides containing metals and semimetals.

[0078] The particle size and shape of the metal oxide particles or resin particles having a refractive index of 1.2 or more and 1.5 or less are not particularly limited, as long as the formed cured film (coating film) can exhibit a light scattering function.

[0079] The average particle diameter of the metal oxide particles or resin particles is preferably 40 nm or more and 600 nm or less. When the average particle diameter of the metal oxide particles or resin particles is 40 nm or more, the cured product exhibits light scattering properties, and the desired light scattering intensity can be adjusted. When the average particle diameter is 600 nm or less, the light transmittance and light scattering intensity can be appropriately adjusted, and the pattern adhesion, pattern linearity, and pattern definition of the cured product can be sufficiently improved.

[0080] Examples of the metal oxide particles include silica particles. As long as the particle size of the silica particles is within the above range, there are no particular limitations on the manufacturing method, such as gas phase reaction or liquid phase reaction, or on the shape (spherical, non-spherical, hollow, solid, etc.). In addition, as long as the particle size is within the above range, silica particles that have been surface-treated with a silane coupling agent treatment or the like can also be used without particular limitations.

[0081] Examples of the resin particles include hollow acrylic resin particles. Hollow acrylic resin particles are, for example, resins in which the shell portion of the hollow particles is radically copolymerized with several types of monomers having (meth)acryloyl groups, and preferably have an average particle diameter of 40 nm to 150 nm and a hollowness of 10% to 90%. For example, the method described in JP 2017-66351 A can be used to produce such hollow acrylic resin particles.

[0082] The average particle size of the metal oxide particles and resin particles can be measured by the cumulant method using, for example, a dynamic light scattering particle size distribution analyzer, "Particle Size Analyzer FPAR-1000" (manufactured by Otsuka Electronics Co., Ltd.). The refractive index of the metal oxide particles (silica particles) and resin particles (hollow acrylic resin particles) can be determined from a transparent mixture obtained by mixing the silica particles or hollow acrylic resin particles processed into a powder with a standard refractive index liquid of known refractive index. In this case, the refractive index of the standard refractive index liquid in the mixture is taken as the refractive index of the silica particles or hollow acrylic resin particles.

[0083] The shapes of the metal oxide particles and resin particles and the hollow ratio of the hollow particles can be observed and measured using a transmission electron microscope (TEM).

[0084] The refractive index of the metal oxide particles and resin particles can be measured using an Abbe refractometer.

[0085] The metal oxide particles or resin particles of component (C) can be dispersed in a solvent together with a dispersant to form a particle dispersion, which can be mixed with other formulation components. The dispersant can be, for example, any known compound used for pigment dispersion (compounds commercially available under the names of dispersants, dispersing wetting agents, dispersion promoters, etc.) without any particular limitation.

[0086] The content of the metal oxide particles or resin particles (component (C)) is preferably 10% by mass or more and 70% by mass or less based on the total mass of the solids. When the content of component (C) is 10% by mass or more, the cured product can be imparted with light scattering properties while maintaining its light transmittance. When the content of component (C) is 70% by mass or less, the development characteristics (pattern adhesion, pattern linearity, pattern definition), light transmittance, and solvent resistance are excellent.

[0087] [(D) component] Component (D) is a photopolymerization initiator. By including component (D), the reaction in the irradiated area proceeds sufficiently, reducing the solubility of the cured area during development, making it possible to form the desired fine pattern. In the present invention, the term "photopolymerization initiator" is used to include sensitizers.

[0088] Examples of component (D) 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; benzophenones such as benzil, benzoin, benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether. Biimidazole compounds such as 2-(o-chlorophenyl)-4,5-phenylbiimidazole, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)biimidazole, 2-(o-fluorophenyl)-4,5-diphenylbiimidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, and 2,4,5-triarylbiimidazole; 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)- Halomethyldiazole compounds such as 1,3,4-oxadiazole and 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4-oxadiazole; 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-phenyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-chlorophenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxyphenyl) halomethyl-s-triazine compounds such as 4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4,5-trimethoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine;O-acetyloxime such as 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(O-benzoyloxime), ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime), 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, etc. Examples of suitable photopolymerization initiators include siloxime compounds; sulfur compounds such as benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, and 2-isopropylthioxanthone; anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, and 2,3-diphenylanthraquinone; organic peroxides such as azobisisobutyronitrile, benzoyl peroxide, and cumene peroxide; and tertiary amines such as triethanolamine and triethylamine. These photopolymerization initiators may be used alone or in combination.

[0089] In particular, when a highly sensitive photopolymerization initiator is required, such as when a large amount of metal oxide is added, when the amount of photopolymerization initiator needs to be reduced, or when photocuring is desired more effectively due to the inability to use a high-temperature heat curing process such as 150°C, O-acyloxime compounds (including ketoximes) are preferred. Among these, compounds represented by general formulas (7) and (8) can be used as more sensitive photopolymerization initiators. Among these, O-acyloxime photopolymerization initiators with a molar absorption coefficient at 365 nm of 10,000 L / mol cm or greater are preferred for low-temperature curing and when photocuring is desired more effectively.

[0090] [ka] (In formula (7), R 10 , R11 each independently represents an alkyl group having 1 to 15 carbon atoms, an aryl group having 6 to 18 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, or a heterocyclic group having 4 to 12 carbon atoms; R 12 represents an alkyl group having 1 to 15 carbon atoms, an aryl group having 6 to 18 carbon atoms, or an arylalkyl group having 7 to 20 carbon atoms. Here, the alkyl group and the aryl group may be substituted with a group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkanoyl group having 1 to 10 carbon atoms, and a halogen, and the alkylene portion may contain an unsaturated bond, an ether bond, a thioether bond, or an ester bond. The alkyl group may be a linear, branched, or cyclic alkyl group.

[0091] [ka] (In formula (8), R 13 and R 14 are each independently a linear or branched alkyl group having 1 to 10 carbon atoms, a cycloalkyl group, a cycloalkylalkyl group, or an alkylcycloalkyl group having 4 to 10 carbon atoms, or a phenyl group which may be substituted with an alkyl group having 1 to 6 carbon atoms. 15 are independently a linear or branched alkyl or alkenyl group having 2 to 10 carbon atoms, and some of the -CH2- groups in the alkyl or alkenyl group may be substituted with -O- groups. 13 ~R 15 A part of the hydrogen atoms in the group may be substituted with halogen atoms.

[0092] The content of component (D) is preferably 0.1% by mass to 30% by mass, and more preferably 1% by mass to 25% by mass, based on the total mass of components (A) and (B). When the content of component (D) is 0.1% by mass or more, the photopolymerization rate is adequate, preventing a decrease in sensitivity. When the content of component (D) is 30% by mass or less, the sensitivity of the composition to exposure light is not too high, allowing faithful reproduction of line widths on the mask and sharp pattern edges.

[0093] [(E) component] The photosensitive resin composition according to an embodiment of the present invention preferably contains an epoxy compound (E). When the photosensitive resin composition is baked at a low temperature of 150° C. or less, the solvent resistance of the cured product can be sufficiently improved by including an epoxy compound (E) as needed.

[0094] Examples of component (E) include epoxy compounds having an aromatic structure such as bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol fluorene type epoxy compounds, bisnaphthol fluorene type epoxy compounds, diphenyl fluorene type epoxy compounds, phenol novolac type epoxy compounds, cresol novolac type epoxy compounds, phenol aralkyl type epoxy compounds, phenol novolac compounds containing a naphthalene skeleton (e.g., NC-7000L, manufactured by Nippon Kayaku Co., Ltd.), naphthol aralkyl type epoxy compounds, trisphenol methane type epoxy compounds (e.g., EPPN-501H, manufactured by Nippon Kayaku Co., Ltd.), and tetrakisphenol ethane type epoxy compounds; glycidyl ethers of polyhydric alcohols; copolymers of monomers having a (meth)acryloyl group, such as glycidyl esters of polycarboxylic acids, copolymers of methacrylic acid and glycidyl methacrylate, copolymers of monomers having a (meth)acryloyl group, including glycidyl (meth)acrylate as a unit; epoxy compounds having a glycidyl group, such as hydrogenated bisphenol A diglycidyl ether (e.g., Rikaresin HBE-100, manufactured by New Japan Chemical Co., Ltd.); 1,4-cyclohexanedimethanol-bis-3,4-epoxycyclohexanecarboxylate, 2-(3,4-epoxy)cyclohexyl-5,1-spiro(3,4-epoxy)cyclohexyl-m-dioxane (e.g., Araldite CY175, manufactured by Huntsman); bis(3,4-epoxycyclohexylmethyl)adipate (e.g., CYRACURE Alicyclic epoxy compounds such as 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (e.g., UVR-6128, manufactured by Dow Chemical Company), 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (e.g., Celloxide 2021P, manufactured by Daicel Corporation), butanetetracarboxylic acid tetra(3,4-epoxycyclohexylmethyl)-modified ε-caprolactone (e.g., Epolead GT401, manufactured by Daicel Corporation), epoxy compounds having an epoxycyclohexyl group (e.g., HiREM-1, manufactured by Shikoku Chemical Industry Co., Ltd.), multifunctional epoxy compounds having a dicyclopentadiene skeleton (e.g., HP7200 series, manufactured by DIC Corporation), 1,2-bis(hydroxymethyl)-1-butanolExamples of such compounds include 2-epoxy-4-(2-oxiranyl)cyclohexane adducts (e.g., EHPE3150, manufactured by Daicel Corporation), epoxidized polybutadiene (e.g., NISSOPB JP-100, manufactured by Nippon Soda Co., Ltd.), and epoxy compounds having a silicone skeleton. These compounds may be used alone or in combination of two or more.

[0095] The epoxy equivalent of component (E) is preferably 100 g / eq or more and 500 g / eq or less, more preferably 130 g / eq or more and 480 g / eq or less. Furthermore, the number average molecular weight (Mn) of component (E) is preferably 100 or more and 5000 or less. When the epoxy equivalent is 100 g / eq or more and the number average molecular weight (Mn) of the epoxy compound is 100 or more, a cured film with good solvent resistance can be obtained. When the epoxy equivalent is 300 g / eq or less and the number average molecular weight (Mn) is 5000 or less, sufficient alkali resistance can be maintained even when alkaline chemicals are used in a subsequent process.

[0096] The epoxy equivalent can be determined, for example, by dissolving the resin solution in dioxane, adding a solution of tetraethylammonium bromide in acetic acid, and titrating with a 1 / 10N perchloric acid solution using a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.) The number average molecular weight (Mn) can be determined in polystyrene terms using, for example, the above-mentioned gel permeation chromatography (GPC) measurement (HLC-8220GPC, manufactured by Tosoh Corporation).

[0097] The content of component (E) is preferably 5% by mass or more and 35% by mass or less, and more preferably 10% by mass or more and 25% by mass or less, based on the total mass of solids. When the content of component (E) is 5% by mass or more, the curing reaction can proceed sufficiently even when baking at a low temperature of 150°C or less. When the content is 35% by mass or less, the development characteristics and solvent resistance of the cured product can be sufficiently improved.

[0098] On the other hand, when the photosensitive resin composition is baked at a high temperature above 150°C, the component (E) tends to harden, so the content of the component (E) is preferably 30 mass % or less based on the total mass of the solid content.

[0099] [Component (F)] The photosensitive resin composition according to one embodiment of the present invention preferably contains (F) an epoxy compound curing agent or curing accelerator. By including the (F) component, the photosensitive resin composition can be sufficiently cured even when baked at a low temperature of 150°C or less.

[0100] Examples of the curing agent for the epoxy compound (F) include amine compounds, polycarboxylic acid compounds, phenol resins, amino resins, dicyandiamide, Lewis acid complex compounds, etc. Among these, polycarboxylic acid compounds are preferred.

[0101] Examples of the polycarboxylic acid compound include polycarboxylic acids, anhydrides of polycarboxylic acids, and thermally decomposable esters of polycarboxylic acids.

[0102] Polycarboxylic acids refer to compounds having two or more carboxy groups in one molecule, and include, for example, succinic acid, maleic acid, cyclohexane-1,2-dicarboxylic acid, cyclohexene-1,2-dicarboxylic acid, cyclohexene-4,5-dicarboxylic acid, norbornane-2,3-dicarboxylic acid, phthalic acid, 3,6-dihydrophthalic acid, 1,2,3,6-tetrahydrophthalic acid, methyltetrahydrophthalic acid, benzene-1,2,4-tricarboxylic acid, cyclohexane-1,2,4-tricarboxylic acid, benzene-1,2,4,5-tetracarboxylic acid, cyclohexane-1,2,4,5-tetracarboxylic acid, and butane-1,2,3,4-tetracarboxylic acid.

[0103] Examples of the anhydrides of polycarboxylic acids include the acid anhydrides of the above compounds. These may be intermolecular acid anhydrides, but acid anhydrides formed by intramolecular ring closure are generally used.

[0104] Examples of the thermally decomposable esters of polycarboxylic acids include t-butyl esters, 1-(alkyloxy)ethyl esters, and 1-(alkylsulfanyl)ethyl esters of the above compounds (wherein alkyl is a saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a branched or cyclic structure and may be substituted with any substituent).

[0105] Furthermore, as the polycarboxylic acid compound, a polymer or copolymer having two or more carboxy groups can also be used, and the carboxy groups may be an anhydride or a thermally decomposable ester.

[0106] Examples of the polymer or copolymer having two or more carboxy groups include a polymer or copolymer containing (meth)acrylic acid as a constituent component, a copolymer containing maleic anhydride as a constituent component, and a compound obtained by reacting a tetracarboxylic dianhydride with a diamine or diol to open the ring of the acid anhydride. Among these, it is preferable to use anhydrides of phthalic acid, 3,6-dihydrophthalic acid, 1,2,3,6-tetrahydrophthalic acid, methyltetrahydrophthalic acid, and benzene-1,2,4-tricarboxylic acid. When a polycarboxylic acid compound is used as a curing agent for an epoxy compound, the blending ratio of the carboxyl groups of the polycarboxylic acid compound is preferably 0.5 to 1.5 moles, more preferably 0.6 to 1.2 moles, per mole of epoxy groups of the epoxy compound.

[0107] The epoxy compound curing accelerator (F) can be a known compound known as an epoxy compound curing accelerator, curing catalyst, latent curing agent, or the like. Examples of epoxy compound curing accelerators include tertiary amines, quaternary ammonium salts, tertiary phosphines, quaternary phosphonium salts, boric acid esters, Lewis acids, organometallic compounds, imidazoles, and the like. Among the above curing accelerators, 1,8-diazabicyclo[5.4.0]undec-7-ene or 1,5-diazabicyclo[4.3.0]non-5-ene, or a salt thereof, is preferred.

[0108] The content of the curing accelerator is preferably 0.05 parts by mass or more and 2 parts by mass or less relative to 100 parts by mass of the epoxy compound. The content of the curing accelerator can be adjusted depending on the state of expression of chemical resistance (solvent resistance) of the resin film pattern after thermal curing, etc.

[0109] When the photosensitive resin composition of the present invention is a composition that is baked at a low temperature of 150° C. or less, the total content of components (E) and (F) is preferably 5% by mass or more and 35% by mass or less, and more preferably 10% by mass or more and 30% by mass or less, based on the total mass of solids. When the total content of components (E) and (F) is 5% by mass or more, sufficient curability is ensured when cured at a low temperature of 150° C. or less, and when it is 35% by mass or less, curability can be improved without adversely affecting patterning ability, linearity, and solvent resistance during alkaline development.

[0110] When the photosensitive resin composition of the present invention is a composition that is baked at a high temperature above 150°C, the total content of components (E) and (F) is preferably 0% by mass or more and 25% by mass or less based on the total mass of the solid content.

[0111] [(G) component] The photosensitive resin composition according to one embodiment of the present invention preferably contains a solvent (G). By including the solvent (G), a liquid photosensitive resin composition containing the above-mentioned components (A) to (F) can be obtained.

[0112] Examples of component (G) include alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol, 3-methoxy-1-butanol, ethylene glycol monobutyl ether, 3-hydroxy-2-butanone, and diacetone alcohol; 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, diethylene glycol ethyl methyl ether, and propylene glycol monobutyl ether. Examples of suitable solvents include glycol ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether; and esters such as ethyl acetate, butyl acetate, ethyl lactate, 3-methoxybutyl acetate, 3-methoxy-3-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. These solvents may be used alone or in combination to achieve the required properties, such as coatability.

[0113] The content of the component (G) varies depending on the target viscosity, but is preferably 60% by mass or more and 90% by mass or less in the photosensitive resin composition solution.

[0114] [(H) component] The photosensitive resin composition according to one embodiment of the present invention preferably contains a coupling agent as component (H), which can improve adhesion to a substrate.

[0115] Examples of component (H) include vinyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-(glycidyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-(phenylamino)propyltrimethoxysilane, and 3-ureidopropyltriethoxysilane.

[0116] [Component (I)] The photosensitive resin composition according to one embodiment of the present invention preferably contains a surfactant as component (I), which allows a uniform coating film to be obtained.

[0117] Examples of the surfactant for component (I) include fluorine-based surfactants, silicone-based surfactants, nonionic surfactants, anionic surfactants, betaine-based surfactants, etc. Of these, fluorine-based surfactants are preferred.

[0118] Examples of fluorine-based surfactants include perfluoroalkyl sulfonic acid compounds, perfluoroalkyl carboxylic acid compounds, perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups on the side chains, etc. The above surfactants may be used alone or in combination of two or more.

[0119] [Other ingredients] The photosensitive resin composition of the present invention may contain additives such as a thermal polymerization inhibitor, an antioxidant, a plasticizer, a leveling agent, an antifoaming agent, and a chain transfer agent, if necessary.

[0120] Examples of the thermal polymerization inhibitor and antioxidant include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine, hindered phenol-based antioxidants, and phosphorus-based heat stabilizers.

[0121] Examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, and the like.

[0122] Examples of the defoaming agent and leveling agent include silicone-based, fluorine-based, and acrylic compounds.

[0123] Examples of the chain transfer agent include thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, and 2-mercaptobenzothiazole.

[0124] The photosensitive resin composition of the present invention can be obtained by mixing the above-mentioned components (A) to (I) and any other components.

[0125] The photosensitive resin composition of the present invention can satisfy the required optical properties and other cured film properties even when using metal oxide or resin particles having a refractive index of 1.2 to 1.5. Furthermore, the photosensitive resin composition of the present invention can be applied to a light-scattering layer that intensifies diffuse transmitted light in order to improve the light extraction efficiency of light-emitting elements such as organic electroluminescence (EL) elements in the development of new display devices, and can also be applied to a light-scattering layer that intensifies diffuse reflected light in display devices that utilize light wavelength conversion of light-emitting elements.

[0126] 2. Manufacturing method of cured film A method for producing a cured film obtained by curing the photosensitive resin composition of the present invention will now be described. The cured film (coating film) of the present invention can be formed by photolithography using the photosensitive resin composition of the present invention.

[0127] [Manufacturing method 1] The method for producing a cured film of the present invention comprises applying the above-described photosensitive resin composition to a substrate having a heat resistance temperature of 150°C or less, exposing the composition through a photomask, removing the unexposed areas by development, and heating the composition at 150°C or less to form a predetermined cured film pattern.

[0128] Examples of substrates that can be used in the cured film manufacturing method of the present invention include resin films (plastic substrates) such as PET (polyethylene terephthalate) and PEN (polyethylene naphthalate) that have a heat resistance temperature of 150°C or less, and substrates in which electrodes such as ITO or gold are vapor-deposited or patterned on a resin film. Here, the "heat resistance temperature" refers to the temperature at which the substrate does not suffer from problems such as deformation when exposed to processing such as pattern formation of a cured film on the substrate. Note that the resin film must have a glass transition temperature (Tg) that does not exceed the Tg, although this temperature varies depending on the degree of stretching treatment.

[0129] Examples of other substrates that can be used in the cured film manufacturing method of the present invention include glass substrates, silicon wafers, and polyimide films, which have high heat resistance but have a thin film or the like with low heat resistance formed thereon. Specific examples of other substrates include substrates with organic devices, such as glass, silicon wafers, or polyimide films, on which an organic light-emitting diode (OLED) or organic thin-film transistor (TFT) is formed. The heat-resistant temperature of the low-heat-resistant substrates targeted by the present invention varies depending on the type of resin and the device, but is preferably 80 to 140°C. Substrates with organic devices also include those on which a protective film or other protective film is formed after the organic device is formed. Even if the heat resistance of these protective films or protective films themselves is 150°C or higher, if they are only heat-resistant to 140°C or less to ensure the functionality of the organic device, they are considered to be substrates with organic devices.

[0130] The photosensitive resin composition can be applied by any coating method. Examples of the coating method include known solution immersion methods and spray methods, as well as methods using a roller coater, land coater, slit coater, or spinner. By using these methods, the photosensitive resin composition can be applied to a desired thickness.

[0131] After applying the coating to the desired thickness using these methods, the solvent is removed (pre-baking) to form a coating film. Pre-baking can be performed by heating using an oven, hot plate, hot air blower, infrared heater, etc., vacuum drying, or a combination of these. The heating temperature and heating time in pre-baking are appropriately selected depending on the solvent used, and are performed, for example, at a temperature of 60 to 110°C (set so as not to exceed the heat resistance temperature of the substrate) for 1 to 3 minutes.

[0132] The exposure performed after pre-baking is carried out by an exposure device, and radiation is applied through a photomask to expose only the resist in the area corresponding to the pattern. The exposure device and its exposure conditions can be selected appropriately. Examples of radiation to be applied include visible light, ultraviolet light, far ultraviolet light, electron beams, and X-rays. Of the above-mentioned radiation, ultraviolet light is preferred. Furthermore, known exposure devices (light sources such as ultra-high pressure mercury lamps, high pressure mercury lamps, metal halide lamps, and far ultraviolet lamps) can be used as the device to apply radiation. Furthermore, the wavelength of the radiation to be applied is preferably 250 nm or more and 400 nm or less. The radiation exposure dose is 25 mJ / cm. 2 More than 3000mJ / cm 2 Preferably, it is 50 mJ / cm or less. 2 More than 2000mJ / cm 2 More preferably, it is:

[0133] The photomask may be a known one, and examples of the photomask include multi-tone masks such as half-tone masks and gray-tone masks.

[0134] In addition, development after exposure is performed to alkali develop the exposed coating film and remove the unexposed portions of the coating film, thereby forming a desired pattern. Examples of coating film development methods include shower development, spray development, dip (immersion) development, and puddle (liquid puddle) development. The above development methods can be performed using commercially available developing machines, ultrasonic cleaners, etc.

[0135] Examples of developers suitable for development include aqueous solutions of alkali metal or alkaline earth metal carbonates, aqueous solutions of alkali metal hydroxides, and aqueous solutions of diethanolamine, tetramethylammonium hydroxide, etc. Among these, a weakly alkaline aqueous solution containing 0.05 to 3 mass % of a carbonate such as sodium carbonate, potassium carbonate, or lithium carbonate can be used at a temperature of 23 to 28°C. After alkaline development, the film is usually washed with water. The developer can be selected appropriately depending on the properties of the resin layer, and a surfactant may be added as needed.

[0136] After development, the coating film is preferably subjected to a heat treatment (post-baking) at a temperature of 80 to 140°C (set so as not to exceed the heat resistance temperature of the substrate) for 20 to 90 minutes, more preferably at a temperature of 90 to 120°C for a heating time of 30 to 60 minutes. The post-baking is carried out for purposes such as increasing the adhesion between the patterned cured film and the substrate. Like pre-baking, post-baking is carried out by heating in an oven, hot plate, or the like. In this manner, the substrate with a patterned cured film of the present invention can be obtained.

[0137] [Manufacturing method 2] The method for producing a cured film of the present invention comprises applying the above-described photosensitive resin composition to a substrate having a heat resistance temperature of more than 150°C, exposing the composition through a photomask, removing the unexposed areas by development, and heating the composition at 150°C or higher to form a predetermined cured film pattern.

[0138] A manufacturing method for forming a predetermined cured film pattern on a substrate with a heat resistance temperature of over 150°C is similar to Manufacturing Method 1, in which coating, exposure, and development are performed. After development, a heat treatment (post-baking) is preferably performed at a temperature of 80 to 250°C for 20 to 90 minutes, and more preferably at a temperature of 180 to 230°C for a heating time of 30 to 60 minutes. The post-baking is performed for purposes such as increasing the adhesion between the patterned cured film and the substrate. This is performed by heating in an oven, hot plate, or the like, as with pre-baking. In this manner, a substrate with a patterned cured film of the present invention can be obtained.

[0139] 3.Cured film The cured film of the present invention can be obtained by curing the above-mentioned photosensitive resin composition by Production Method 1 or Production Method 2.

[0140] The cured film of the present invention, when formed on a transparent substrate, preferably has a transmittance of 80% or more in the visible light region, and when the transparent substrate on which the cured film is formed is irradiated with white light perpendicularly, the intensity of scattered light at 60°, where the angle of straight-ahead direct transmitted light is set to 0°, is 10% or more but less than 80% of the intensity of scattered light at 5°, where the angle of straight-ahead direct transmitted light is set to 0°.

[0141] The cured film of the present invention satisfies the above-mentioned optical properties (transmittance in the visible light region and light scattering property), and when formed on a transparent substrate, when the transparent substrate on which the cured film is formed is irradiated with white light perpendicularly, the intensity of scattered light at 120°, where the angle of the straight-ahead direct transmitted light is set to 0°, is preferably less than 80%, and more preferably less than 50%, of the intensity of scattered light at 60°, where the angle of the straight-ahead direct transmitted light is set to 0°.

[0142] When measuring the transmittance and scattered light intensity of the substrate with the cured film, the substrate is a transparent substrate, and for example, a transparent glass substrate "EagleXG" (manufactured by Corning Incorporated) can be used.

[0143] By setting the intensity of the scattered light within the above range, it is possible to provide a light scattering layer that enhances the diffuse transmitted light in order to improve the light extraction efficiency of a light emitting device such as an organic EL device.

[0144] The cured film of the present invention can also be used as a light wavelength conversion layer with improved light confinement effect by adding quantum dots or fluorescent substances for light wavelength conversion, which highly diffuses light emitted from a light-emitting element. Furthermore, in order to use the cured film as a light scattering layer that enhances diffuse reflection for a display device that utilizes the light wavelength conversion of a light-emitting element, it is preferable that the intensity of scattered light at 120°, when the angle of the straight-traveling direct transmitted light is 0°, exceeds 80% of the intensity of scattered light at 60°, when the angle of the straight-traveling direct transmitted light is 0°. For such applications, it is preferable to use magnesium fluoride or hollow silica, which have a smaller refractive index.

[0145] 4.Display device The display device of the present invention has the above-described cured film. Since the display device of the present invention has the above-described cured film, it can have a light-scattering layer that can improve the light extraction efficiency of a light-emitting element such as an organic EL element. [Example]

[0146] Hereinafter, the embodiments of the present invention will be specifically described based on examples and comparative examples, but the present invention is not limited to these.

[0147] First, we will explain the synthesis examples of the alkali-soluble resin (component A). Unless otherwise specified, the resins in these synthesis examples were evaluated as follows. When the same model of measuring equipment was used, the name of the equipment manufacturer was omitted from the second line onwards. In addition, in [Experiment 1] and [Experiment 2], all glass substrates used to prepare substrates with cured films for measurement were glass substrates that had undergone the same treatment.

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

[0149] [Epoxy equivalent] The epoxy equivalent was determined by dissolving the resin solution in dioxane, adding a solution of tetraethylammonium bromide in acetic acid, and titrating with a 1 / 10N perchloric acid solution using a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.).

[0150] [Acid value] The acid value was determined by dissolving the resin solution in dioxane and titrating it with a 1 / 10N KOH aqueous solution using a potentiometric titrator "COM-1600."

[0151] [Molecular weight] The molecular weight was measured using gel permeation chromatography (GPC) "HLC-8220GPC" (manufactured by Tosoh Corporation, solvent: tetrahydrofuran, columns: TSKgelSuper H-2000 (2 columns) + TSKgelSuper H-3000 (1 column) + TSKgelSuper H-4000 (1 column) + TSKgelSuper H-5000 (1 column) (manufactured by Tosoh Corporation), temperature: 40°C, rate: 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).

[0152] [Refractive Index] The refractive indexes of the silica particles and hollow acrylic resin particles were measured using an Abbe refractometer.

[0153] [Average particle size] The average particle diameters of the silica particles and hollow acrylic resin particles were 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.).

[0154] The abbreviations used in the synthesis examples are as follows. DCPMA: dicyclopentanyl methacrylate GMA: Glycidyl methacrylate St: styrene AA: acrylic acid SA: Succinic anhydride BPFE: Bisphenolfluorene type epoxy compound (reaction product of 9,9-bis(4-hydroxyphenyl)fluorene and chloromethyloxirane) BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride THPA: Tetrahydrophthalic anhydride TEAB: Tetraethylammonium bromide AIBN: Azobisisobutyronitrile TDMAMP: Trisdimethylaminomethylphenol HQ: Hydroquinone TEA: Triethylamine PGMEA: Propylene glycol monomethyl ether acetate

[0155] [Synthesis Example 1] A 500 ml four-neck flask equipped with a reflux condenser was charged with BPFE (114.4 g, 0.23 mol), AA (33.2 g, 0.46 mol), PGMEA (157 g), and TEAB (0.48 g) and stirred at 100-105°C for 20 hours to react. Next, BPDA (35.3 g, 0.12 mol) and THPA (18.3 g, 0.12 mol) were charged to the flask and stirred at 120-125°C for 6 hours to obtain resin solution (A)-1. The solids concentration of the resin solution was 56.1 mass%, the acid value (solids equivalent) was 103 mg KOH / g, and the Mw by GPC analysis was 3600.

[0156] [Synthesis Example 2] PGMEA (300 g) was placed in a 1 L four-neck flask equipped with a reflux condenser, and the flask was purged with nitrogen and then heated to 120° C. A monomer mixture (DCPMA (77.1 g, 0.35 mol), GMA (49.8 g, 0.35 mol), St (31.2 g, 0.30 mol) dissolved in AIBN (10 g)) was added dropwise to the flask from a dropping funnel over 2 hours, followed by stirring at 120° C. for an additional 2 hours to obtain a copolymer solution.

[0157] Next, after replacing the atmosphere in the flask with air, AA (24.0 g (95% of glycidyl groups)), TDMAMP (0.8 g), and HQ (0.15 g) were added to the resulting copolymer solution and stirred at 120 ° C for 6 hours to obtain a polymerizable unsaturated group-containing copolymer solution. Furthermore, SA (30.0 g (90% of the moles of AA added)) and TEA (0.5 g) were added to the resulting polymerizable unsaturated group-containing copolymer solution and reacted at 120 ° C for 4 hours to obtain resin solution (A)-2. The solids concentration of the resin solution was 41.7% by mass, the acid value (solids equivalent) was 76 mg KOH / g, and the Mw by GPC analysis was 5300.

[0158] The components used in the photosensitive resin compositions of the following examples are as follows:

[0159] (alkali-soluble resin) (A)-1: Resin solution obtained in Synthesis Example 1 (solid content concentration: 56.1% by mass) (A)-2: Resin solution obtained in Synthesis Example 2 (solid content concentration: 41.7% by mass)

[0160] (Photopolymerizable monomer) (B): Dipentaerythritol penta / hexaacrylate mixture (KAYARAD DPHA, acrylic equivalent 96-115 g / eq, manufactured by Nippon Kayaku Co., Ltd., "KAYARAD" is a registered trademark of the company)

[0161] (metal oxide particles or resin particles) (C)-1: Hollow acrylic particle dispersion of Techpolymer NH (average particle diameter 65 nm, porosity 30% by volume, refractive index 1.33) at a concentration of 10% by mass and PGMEA at 90% by mass (C)-2: Silica particle dispersion containing silica particles "Admanano YA050C" (average particle diameter 50 nm, refractive index 1.45) at a concentration of 20% by mass, dispersant (DISPERBYK-355) at 5% by mass, and PGMEA at 75% by mass (C)-3: Silica particle dispersion containing silica particles (average particle diameter 400 nm, refractive index 1.45) at a concentration of 20% by mass, dispersant (DISPERBYK-355) at 5% by mass, and PGMEA at 75% by mass (C)-4: Silica particle dispersion with a silica particle (average particle diameter 600 nm, refractive index 1.45) concentration of 20% by mass, dispersant (DISPERBYK-355) 5% by mass, and PGMEA 75% by mass

[0162] Techpolymer NH is manufactured by Sekisui Chemical Co., Ltd., and "Techpolymer" is a registered trademark of the company. Admanano YA050C is manufactured by Admatechs Co., Ltd., and "Admanano" is a registered trademark of the company. DISPERBYK-355 is manufactured by BYK-Chemie Co., Ltd., and "DISPERBYK" is a registered trademark of the company.

[0163] (Photopolymerization initiator) (D): 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(O-benzoyloxime) (IrgacureOXE-01, manufactured by BASF, "Irgacure" is a registered trademark of the company)

[0164] (epoxy compounds) (E): 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (Celloxide 2021P (epoxy equivalent 135 g / eq), manufactured by Daicel Corporation; "Celloxide" is a registered trademark of the company)

[0165] (hardening agent and hardening accelerator) (F)-1: Benzene 1,2,4-tricarboxylic acid-1,2-anhydride (F)-2: PGMEA solution containing 2% by mass of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU®, manufactured by San-Apro Co., Ltd.)

[0166] (solvent) (G)-1: Propylene glycol monomethyl ether acetate (PGMEA) (G)-2: Ethyl lactate (EL) (G)-3: Diethylene glycol ethyl methyl ether (EDM)

[0167] (Other additives) (coupling agent) (H): 3-glycidoxypropyltrimethoxysilane (surfactant) (I): Megafac F-477 (manufactured by DIC Corporation, "Megafac" is a registered trademark of the company)

[0168] [Experiment 1] The above ingredients were mixed in the proportions shown in Table 1 to prepare photosensitive resin compositions of Examples 1 to 6 and Comparative Examples 1 and 2. All values in Table 1 are in mass %.

[0169] [Table 1]

[0170] [evaluation] The photosensitive resin compositions of Examples 1 to 6 and Comparative Examples 1 and 2 were used to carry out the following evaluations.

[0171] (Preparation of substrate with cured film (coating film) for evaluation of development characteristics) The photosensitive resin composition shown in Table 1 was previously exposed to a low-pressure mercury lamp at a wavelength of 254 nm and an illumination intensity of 1000 mJ / cm. 2The coating was applied using a spin coater to a 125 mm x 125 mm glass substrate "#1737" (manufactured by Corning Incorporated) (hereinafter referred to as "glass substrate") whose surface had been cleaned by irradiating it with ultraviolet light of 1000 W / cm , so that the film thickness after heat curing would be 2.0 μm, and the coating was prebaked on a hot plate at 90°C for 2 minutes to produce a hardened film (coating). Next, a negative photomask with a line / space of 10 μm / 10 μm to 50 μm / 50 μm was used to apply a photoresist to the hardened film (coating) at an i-line illuminance of 30 mW / cm . 2 50mJ / cm with an ultra-high pressure mercury lamp 2 The photocuring reaction was carried out by irradiating the film with ultraviolet light.

[0172] The exposed cured film (coating film) was then soaked in a 0.04% potassium hydroxide solution at 25°C at 1 kgf / cm 2 After developing for 20 seconds from the development time (break time = BT) when the pattern begins to appear, the shower pressure was increased to 5 kgf / cm. 2 The unexposed portions of the cured film (coating film) were removed to form a cured film pattern on the glass substrate, which was then post-cured (post-baked) at 90°C for 60 minutes using a hot air dryer to obtain a substrate with a cured film (coating film) for evaluation of development properties.

[0173] [Development characteristics evaluation] (pattern adhesion) (Evaluation method) After the main curing (post-baking), the 20 μm mask pattern was observed under an optical microscope. A grade of △ or better was considered to be acceptable.

[0174] (Evaluation criteria) ○: The cured film (coating film) has not peeled off at all. △: Part of the cured film (coating film) is peeling off ×: Most of the cured film (coating film) is peeled off

[0175] (pattern linearity) (Evaluation method) After the main curing (post-baking), the 20 μm mask pattern was observed under an optical microscope. A grade of △ or better was considered to be acceptable.

[0176] (Evaluation criteria) ○: No jagged edges are observed on the pattern edges △: Jagged edges are observed in some areas of the pattern. ×: Jagged edges are observed in most of the pattern edges.

[0177] (pattern definition) (Evaluation method) After the main curing (post-baking), the 10 to 50 μm mask pattern was observed under an optical microscope.

[0178] (Evaluation criteria) ◎: A pattern of 10 μm or more and less than 15 μm is formed ○: A pattern of 15 μm or more and less than 24 μm is formed △: A pattern of 24 μm or more and less than 50 μm is formed ×: No pattern is formed

[0179] [Solvent resistance evaluation] (Preparation of substrate with cured film (coating film) for solvent resistance evaluation) The photosensitive resin composition shown in Table 1 was applied to a glass substrate using a spin coater so that the film thickness after heat curing would be 2.0 μm, and the applied film was prebaked on a hot plate at 90°C for 2 minutes to produce a cured film (coating film). Next, a negative photomask with a line / space of 20 μm / 20 μm was placed on the cured film (coating film), and an i-line illuminance of 30 mW / cm was applied. 2 50mJ / cm with an ultra-high pressure mercury lamp 2 The photocuring reaction was carried out by irradiating the film with ultraviolet light.

[0180] The exposed cured film (coating film) was then soaked in a 0.05% potassium hydroxide solution at 25°C at 1 kgf / cm 2 After developing for 60 seconds at a shower pressure of 5kgf / cm 2The unexposed portions of the cured film (coating film) were removed to form a cured film pattern on the glass substrate, which was then post-cured (post-baked) at 90°C for 60 minutes using a hot air dryer to obtain a substrate with a cured film (coating film) for solvent resistance evaluation.

[0181] (Evaluation method) The surface of the cured film (coating film) formed on the glass substrate was rubbed back and forth 20 times with a cloth soaked in PGMEA. A grade of fair or better was considered to be acceptable.

[0182] (Evaluation criteria) ○: No dissolution or scratches on the surface of the cured film (coating film) △: Dissolution is observed in a small area on the surface of the cured film (coating film), and there are also small scratches. ×: The surface of the cured film (coating film) is softened and most of it is scratched

[0183] [Optical property evaluation] (transmittance) (Evaluation method) Using the same cured film (coating) substrate as the one prepared for solvent resistance evaluation, the transmittance in the visible light region of 380 nm to 780 nm was measured using a UV-Vis-NIR spectrophotometer "UH4150" (manufactured by Hitachi High-Tech Science Corporation). A grade of △ or better was considered to be acceptable.

[0184] (Evaluation criteria) ○: Transmittance is 80% or more △: Transmittance is 70% or more and less than 80% ×: Transmittance is less than 70%

[0185] (light scattering) A substrate with a cured film (coating film) similar to the substrate with a cured film (coating film) prepared for the solvent resistance evaluation was irradiated perpendicularly with white light, and the transmitted and scattered light was measured using a goniophotometer "GP-1" (manufactured by Nikka Densoku Co., Ltd.).

[0186] (Evaluation criteria: Light scattering 1) ○: The scattered light intensity at 5° and 60° is evaluated assuming that the angle of direct transmitted light is 0°, and the scattered light intensity at 60° is more than 20% of the scattered light intensity at 5°. △: The scattered light intensity at 5° and 60° is evaluated assuming that the angle of direct transmitted light is 0°. The scattered light intensity at 60° is 10% to 20% of the scattered light intensity at 5°. ×: The scattered light intensity at 60° is less than 10% of the scattered light intensity at 5° when the angle of the directly transmitted light is set to 0°.

[0187] (Evaluation criteria: Light scattering 2) A: The scattered light intensity at 60° and 120° is evaluated assuming that the angle of direct transmitted light is 0°. The scattered light intensity at 120° is less than 50% of the scattered light intensity at 60°. B: The scattered light intensity at 60° and 120° is evaluated assuming that the angle of direct transmitted light is 0°. The scattered light intensity at 120° is 50% or more but less than 80% of the scattered light intensity at 60°. C: The scattered light intensity at 60° and 120° is evaluated when the angle of the directly transmitted light is set to 0°. The scattered light intensity at 120° is 80% or more of the scattered light intensity at 60°.

[0188] The results of the above evaluations are shown in Table 2.

[0189] [Table 2]

[0190] As is clear from the results of Examples 1 to 6 and Comparative Examples 1 and 2, it was found that by using a photosensitive resin composition containing an alkali-soluble resin represented by general formula (1) of the present invention and hollow acrylic resin particles or silica particles having specific physical properties (refractive index, average particle size, etc.), it is possible to prepare a cured film that has excellent light scattering properties and is capable of forming a fine pattern. Furthermore, in the light scattering evaluation, when light scattering property 1 is evaluated as ○ and light scattering property 2 is evaluated as A, it indicates that the diffuse transmitted light is strong, and it is also found to be optimal as a layer for improving the light extraction efficiency of light emitted from a light-emitting element.

[0191] [Experiment 2] The above ingredients were mixed in the proportions shown in Table 3 to prepare photosensitive resin compositions of Examples 7 to 12 and Comparative Examples 3 and 4. All values in Table 3 are in mass %.

[0192] [Table 3]

[0193] [evaluation] The cured films (coating films) obtained by curing the photosensitive resin compositions of Examples 7 to 12 and Comparative Examples 3 and 4 were evaluated as follows.

[0194] (Preparation of substrate with cured film (coating film) for evaluation of development characteristics) The photosensitive resin compositions shown in Table 3 were applied to a glass substrate using a spin coater so that the film thickness after heat curing would be 2.0 μm, and the substrate was prebaked at 90°C for 2 minutes using a hot plate to produce a hardened film (coating). Next, the exposure gap was adjusted to 100 μm, and a negative photomask of 10 to 50 μm (in 5 μm increments) was placed on the hardened film (coating), and an i-line illuminance of 30 mW / cm was applied. 2 50mJ / cm with an ultra-high pressure mercury lamp 2 The photocuring reaction was carried out by irradiating the film with ultraviolet light.

[0195] The exposed cured film (coating film) was then soaked in a 0.04% potassium hydroxide solution at 25°C at 1 kgf / cm 2After developing for 20 seconds from the development time (break time = BT) when the pattern begins to appear, the shower pressure was increased to 5 kgf / cm. 2 The unexposed portions of the cured film (coating film) were removed to form a cured film pattern on the glass substrate, which was then post-cured (post-baked) at 230°C for 30 minutes using a hot air dryer to obtain a substrate with a cured film (coating film) for evaluation of development properties.

[0196] [Development characteristics evaluation] (pattern adhesion) (Evaluation method) After the main curing (post-baking), the 20 μm mask pattern was observed under an optical microscope. A grade of △ or better was considered to be acceptable.

[0197] (Evaluation criteria) ○: The cured film (coating film) has not peeled off at all. △: Part of the cured film (coating film) is peeled off ×: Most of the cured film (coating film) is peeled off

[0198] (pattern linearity) (Evaluation method) After the main curing (post-baking), the 20 μm mask pattern was observed under an optical microscope. A grade of △ or better was deemed to be acceptable.

[0199] (Evaluation criteria) ○: No jagged edges are observed on the pattern edges △: Jagged edges are observed in some areas of the pattern. ×: Jagged edges are observed in most of the pattern edges.

[0200] (pattern definition) (Evaluation method) After the main curing (post-baking), the 10 to 50 μm mask pattern was observed under an optical microscope.

[0201] (Evaluation criteria) ◎: A pattern of 10 μm or more and less than 15 μm is formed ○: A pattern of 15 μm or more and less than 24 μm is formed △: A pattern of 24 μm or more and less than 50 μm is formed ×: No pattern is formed

[0202] [Transmittance evaluation] (Evaluation method) Using the same cured film (coating) substrate as the one prepared for solvent resistance evaluation, the transmittance in the visible light region of 380 nm to 780 nm was measured using a UV-Vis-NIR spectrophotometer "UH4150." A score of ○ or higher was considered to be acceptable.

[0203] (Evaluation criteria) ○: Transmittance is 80% or more △: Transmittance is 70% or more and less than 80% ×: Transmittance is less than 70%

[0204] [Evaluation of light scattering] (Preparation of substrate with cured film (coating film) for light scattering evaluation) The photosensitive resin compositions shown in Table 3 were applied to a glass substrate using a spin coater so that the film thickness after heat curing would be 2.0 μm, and the applied film was prebaked on a hot plate at 90°C for 2 minutes to produce a hardened film (coated film). Next, without covering it with a negative photomask, the applied film was exposed to an i-line illuminance of 30 mW / cm. 2 50mJ / cm with an ultra-high pressure mercury lamp 2 The photocuring reaction was carried out by irradiating the film with ultraviolet light.

[0205] The exposed cured film (coating film) was then soaked in a 0.05% potassium hydroxide solution at 25°C at 1 kgf / cm 2 After developing for 20 seconds from the development time (break time = BT) when the pattern begins to appear, the shower pressure was increased to 5 kgf / cm. 2 The unexposed portions of the cured film (coating film) were removed to form a cured film pattern on the glass substrate, which was then post-cured (post-baked) at 230° C. for 30 minutes using a hot air dryer.

[0206] (Evaluation method) A cured film (coating film) similar to the cured film (coating film) prepared for evaluating solvent resistance was irradiated perpendicularly with white light, and the transmitted and scattered light was measured using a goniophotometer.

[0207] (Evaluation criteria: Light scattering 1) ○: The scattered light intensity at 5° and 60° is evaluated assuming that the angle of direct transmitted light is 0°, and the scattered light intensity at 60° is more than 20% of the scattered light intensity at 5°. △: The scattered light intensity at 5° and 60° is evaluated assuming that the angle of direct transmitted light is 0°. The scattered light intensity at 60° is 10% to 20% of the scattered light intensity at 5°. ×: The scattered light intensity at 60° is less than 10% of the scattered light intensity at 5° when the angle of the directly transmitted light is set to 0°.

[0208] (Evaluation criteria: Light scattering 2) A: The scattered light intensity at 60° and 120° is evaluated assuming that the angle of direct transmitted light is 0°. The scattered light intensity at 120° is less than 50% of the scattered light intensity at 60°. B: The scattered light intensity at 60° and 120° is evaluated assuming that the angle of direct transmitted light is 0°. The scattered light intensity at 120° is 50% or more but less than 80% of the scattered light intensity at 60°. C: The scattered light intensity at 60° and 120° is evaluated when the angle of the directly transmitted light is set to 0°. The scattered light intensity at 120° is 80% or more of the scattered light intensity at 60°.

[0209] The results of the above evaluations are shown in Table 4.

[0210] [Table 4]

[0211] As is clear from the results of Examples 7 to 12 and Comparative Examples 3 and 4, it was found that by using a photosensitive resin composition containing an alkali-soluble resin represented by general formula (1) of the present invention and hollow acrylic resin particles and silica particles having specific physical properties (refractive index, average particle size, etc.), it is possible to prepare a cured film that has excellent light scattering properties and is capable of forming a fine pattern. Furthermore, in the light scattering evaluation, when light scattering property 1 is evaluated as ○ and light scattering property 2 is evaluated as A, it indicates that the diffuse transmitted light is strong, and it is also found to be optimal as a layer for improving the light extraction efficiency of light emitted from a light-emitting element. [Industrial Applicability]

[0212] The photosensitive resin composition of the present invention can provide a substrate with a cured film having excellent light scattering properties. Therefore, it is useful for, for example, display devices. Specifically, since the pattern can be formed by photolithography, it has the advantage of being able to be formed using existing photolithography processes. Furthermore, since film strength can be obtained even at low temperatures, it is suitable for the production of touch panels and color filters that use substrates with low heat resistance. Regarding light scattering properties, the cured film can be designed according to the required characteristics depending on the application. It can be used as a layer for improving the light extraction efficiency of light emitted from a light-emitting element, where increased intensity of diffuse transmitted light is required, or as a layer for improving the high diffusion and trapping efficiency of light emitted from a light-emitting element, where increased intensity of diffuse reflected light is required.

Claims

[Claim 1] (A) an unsaturated group-containing alkali-soluble resin; (B) a photopolymerizable monomer having at least two ethylenically unsaturated bonds; (C) metal oxide particles or resin particles having an average particle diameter of 40 nm or more and 600 nm or less and a refractive index of 1.2 or more and 1.5 or less; (D) a photopolymerization initiator; Including, The content of the component (C) is 10% by mass or more and 70% by mass or less based on the total mass of the solid content. Photosensitive resin composition.

Images