Photosensitive resin composition and organic EL element partition

Abstract

Provided is a high-sensitivity photosensitive resin composition which contains a black colorant and by which development and pattern formation are possible even at low amounts of light exposure. This photosensitive resin composition comprises: (A) a binder resin; (B1) a first quinone diazide adduct, which is a quinone diazide adduct to a first phenol compound; (B2) a second quinone diazide adduct, which is a quinone diazide adduct to a second phenol compound; and (C) a black colorant. The difference between the molecular weight of the first phenol compound and the molecular weight of the second phenol compound is 40-500. The molecular weight of the first phenol compound is smaller than the molecular weight of the second phenol compound.

Description

[Technical Field]

[0001] The present invention relates to a photosensitive resin composition, and to an organic EL element partition, an organic EL element insulating film, and an organic EL element using the same. More specifically, the present invention relates to a photosensitive resin composition containing a black coloring agent, and to an organic EL element partition, an organic EL element insulating film, and an organic EL element using the same. [Background technology]

[0002] In display devices such as organic light-emitting diode (OLED) displays, partition materials are used in the gaps between colored patterns within the display area or at the edges of the peripheral areas of the display area to improve display characteristics. In the manufacture of OLED display devices, partitions are first formed to prevent organic material pixels from coming into contact with each other, and then organic material pixels are formed between these partitions. These partitions are generally formed by photolithography using a photosensitive resin composition and are insulating. Specifically, a photosensitive resin composition is applied to a substrate using a coating apparatus, volatile components are removed by means of heating or other means, and then the image is exposed through a mask. Next, in the case of a negative type, the unexposed areas are removed with a developer such as an alkaline aqueous solution, and in the case of a positive type, the exposed areas are removed with a developer such as an alkaline aqueous solution. The resulting pattern is then heat-treated to form partitions (insulating films). Subsequently, organic materials that emit red, green, and blue light are deposited between the partitions using an inkjet method or the like to form the pixels of the OLED display device.

[0003] In recent years, the miniaturization of display devices and the diversification of displayed content have led to a demand for higher performance and resolution of pixels in this field. Attempts have been made to enhance contrast and improve visibility in display devices by using colorants to give partition materials light-shielding properties. However, when partition materials are given light-shielding properties, the photosensitive resin composition tends to become less sensitive, potentially leading to longer exposure times and reduced productivity. Therefore, the photosensitive resin composition used to form partition materials containing colorants is required to be more sensitive.

[0004] Patent Document 1 (Japanese Patent Application Laid-Open No. 2001-281440) describes a composition obtained by adding titanium black to a positive-type radiation-sensitive resin composition containing an alkali-soluble resin and a quinonediazide compound as a radiation-sensitive resin composition that exhibits high light-shielding properties after heat treatment after exposure.

[0005] Patent Document 2 (Japanese Patent Application Laid-Open No. 2002-116536) describes a method for blackening a partition wall using carbon black in a radiation-sensitive resin composition containing [A] an alkali-soluble resin, [B] a 1,2-quinonediazide compound, and [C] a colorant.

[0006] Patent Document 3 (Japanese Patent Application Laid-Open No. 2010-237310) describes a composition obtained by adding a thermosensitive dye to a positive-type radiation-sensitive resin composition containing an alkali-soluble resin and a quinonediazide compound as a radiation-sensitive resin composition that exhibits light-shielding properties after heat treatment after exposure.

[0007] Patent Document 4 (International Publication No. 2017 / 069172) describes a positive-type photosensitive resin composition containing at least one black dye selected from (A) a binder resin, (B) a quinonediazide compound, and (C) a black dye defined by the Color Index of Solvent Black 27 to 47.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0009] In photosensitive resin compositions used to form colored partition materials, a considerable amount of colorant is required to sufficiently enhance the light-shielding properties of the cured film. When such a large amount of colorant is used, the radiation irradiated onto the film of the photosensitive resin composition is absorbed by the colorant, reducing the effective intensity of the radiation in the film. As a result, the photosensitive resin composition is not sufficiently exposed, and consequently, the pattern-forming properties are reduced.

[0010] In forming partitions in organic EL elements, high sensitivity of the material forming the partitions is crucial from the standpoint of productivity. However, when using a black photosensitive resin composition containing a colorant, exposure defects occur under commonly used exposure conditions, requiring, for example, longer exposure times, which reduces productivity. Therefore, there is a strong desire to reduce the exposure amount of the photosensitive resin composition, thereby lowering energy costs and increasing throughput.

[0011] The object of the present invention is to provide a highly sensitive photosensitive resin composition containing a black coloring agent that can be developed and patterned even with low exposure. [Means for solving the problem]

[0012] The inventors have discovered that a photosensitive resin composition containing a binder resin, a quinone diazide adduct of a phenol compound, and a black coloring agent can be developed and patterned even at low exposure levels, despite containing a black coloring agent, by using a system that includes multiple quinone diazide adducts of phenol compounds with different molecular weights.

[0013] In other words, the present invention includes the following embodiments. [1] (A) Binder resin and (B1) The first quinone diazide adduct, which is a quinone diazide adduct to the first phenol compound, (B2) The second quinone diazide adduct, which is a quinone diazide adduct to the second phenol compound, (C) Black coloring agent and A photosensitive resin composition comprising the first phenol compound and the second phenol compound, wherein the difference between the molecular weight of the first phenol compound and the molecular weight of the second phenol compound is 40 to 500, and the molecular weight of the first phenol compound is smaller than the molecular weight of the second phenol compound. [2] The photosensitive resin composition according to [1], wherein the first phenol compound and the second phenol compound each have three or more phenolic hydroxyl groups. [3] The photosensitive resin composition according to either [1] or [2], wherein the phenolic hydroxyl group equivalent of the first quinone diazide adduct is 100 to 1500, and the phenolic hydroxyl group equivalent of the second quinone diazide adduct is 180 to 800. [4] The photosensitive resin composition according to any one of [1] to [3], wherein the average number of phenolic hydroxyl groups of the first quinone diazide adduct is 0.1 to 3.0 per molecule, and the average number of phenolic hydroxyl groups of the second quinone diazide adduct is 0.5 to 5.0 per molecule. [5] The photosensitive resin composition according to any one of [1] to [4], wherein the first quinone diazide adduct is a 1,2-naphthoquinone diazide-4-sulfonic acid ester or a 1,2-naphthoquinone diazide-5-sulfonic acid ester of the first phenol compound. [6] The photosensitive resin composition according to any one of [1] to [5], wherein the second quinone diazide adduct is a 1,2-naphthoquinone diazide-4-sulfonic acid ester or a 1,2-naphthoquinone diazide-5-sulfonic acid ester of the second phenol compound. [7] A photosensitive resin composition according to any one of [1] to [6], wherein the molecular weight of the first phenol compound is 230 or more and less than 300, and the molecular weight of the second phenol compound is 300 or more and 600 or less. [8] A photosensitive resin composition according to any one of [1] to [7], comprising 5 to 70 parts by mass of the first quinone diazide adduct and 5 to 70 parts by mass of the second quinone diazide adduct, based on 100 parts by mass of the binder resin. [9] The photosensitive resin composition according to any one of [1] to [8], wherein the mass ratio of the first quinone diazide adduct to the second quinone diazide adduct (mass of the first quinone diazide adduct:mass of the second quinone diazide adduct) is 1:13 to 13:1.

[10] The binder resin comprises a copolymer of a polymerizable monomer having an alkali-soluble functional group and other polymerizable monomers, wherein the copolymer of the alkali-soluble functional group and other polymerizable monomers is of formula (1) [ka] (In equation (1), R 1 (where a is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a is an integer from 1 to 5.) A photosensitive resin composition according to any one of [1] to [9], having a structural unit represented by .

[11] The binder resin comprises a resin having epoxy groups and phenolic hydroxyl groups, wherein the resin having epoxy groups and phenolic hydroxyl groups is a reaction product of a compound having at least two epoxy groups in one molecule and a hydroxybenzoic acid compound, and the formula is (7) [ka] (In equation (7), b is an integer between 1 and 5, and * represents the binding site with the residue excluding the epoxy group involved in the reaction, for a compound having at least two epoxy groups in one molecule.) A photosensitive resin composition according to any one of [1] to

[10] , which is a compound having the structure of [1].

[12] The photosensitive resin composition according to

[11] , wherein the compound having at least two epoxy groups in one molecule is a novolac-type epoxy resin.

[13] The aforementioned binder resin is of formula (4) [ka] (In equation (4), R 9 R is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 10 (where r is an acid-degradable group, r is an integer between 0 and 5, s is an integer between 0 and 5, and r+s is an integer between 1 and 5.) A photosensitive resin composition according to any one of [1] to

[12] , comprising a resin having a structural unit represented by formula (4) in which s is an integer of 1 or more.

[14] The photosensitive resin composition according to any one of [1] to

[13] , wherein the optical density (OD value) of the cured film of the photosensitive resin composition is 0.5 or more per 1 μm of film thickness.

[15] The photosensitive resin composition according to any one of [1] to

[14] , wherein the black coloring agent is a dye defined by the color index (CI) of Solvent Black 27 to 47.

[16] A photosensitive resin composition according to any one of [1] to

[15] , comprising 10 to 150 parts by mass of the black coloring agent based on 100 parts by mass of the binder resin.

[17] An organic EL element partition comprising a cured product of a photosensitive resin composition described in any of [1] to

[16] .

[18] An insulating film for an organic EL element containing a cured product of a photosensitive resin composition described in any of [1] to

[16] .

[19] An organic EL element comprising a cured product of a photosensitive resin composition described in any of [1] to

[16] . [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a highly sensitive photosensitive resin composition containing a black coloring agent that can be developed and patterned even with low exposure. [Modes for carrying out the invention]

[0015] The present invention will be described in detail below.

[0016] In this disclosure, "alkali soluble" and "alkali aqueous solution soluble" mean that a photosensitive resin composition or its components, or a coating or cured coating of a photosensitive resin composition, is soluble in a 2.38% by mass aqueous solution of tetramethylammonium hydroxide. "Alkali soluble functional group" means a group that imparts such alkali solubility to a photosensitive resin composition or its components, or a coating or cured coating of a photosensitive resin composition. Examples of alkali soluble functional groups include phenolic hydroxyl groups, carboxyl groups, sulfo groups, phosphoric acid groups, acid anhydride groups, and mercapto groups.

[0017] In this disclosure, "acid-degradable group" means a group that decomposes (deprotects) in the presence of an acid, and optionally by heating, to generate an alkali-soluble functional group.

[0018] In this disclosure, "radical polymerizable functional group" means an ethylenically unsaturated group, and "radical polymerizable compound" means a compound having one or more ethylenically unsaturated groups.

[0019] In this disclosure, "structural unit" means an atomic group that constitutes a part of the basic structure of a polymer, and this atomic group may have pendant atoms or pendant atomic groups. For example, in the case of a radical (co)polymer, it means a unit derived from a radical polymerizable compound used as a monomer, and in the case of a phenol novolac resin, it means the following unit formed by the condensation reaction of one molecule of phenol (C6H5OH) and one molecule of formaldehyde (HCHO). With respect to structural units having pendant groups (side groups), structural units having pendant groups or groups derived therefrom that are used in the formation of crosslinking sites are considered to be different from structural units having free pendant groups that are not involved in the formation of crosslinking sites. With respect to a polymer having branched molecular chains, structural units containing branching points (branched units) and structural units included in linear molecular chains are considered to be different from each other. [ka]

[0020] In this disclosure, "(meth)acrylic" means acrylic or methacrylic, "(meth)acrylate" means acrylate or methacrylate, and "(meth)acryloyl" means acryloyl or methacryloyl.

[0021] In this disclosure, the number-average molecular weight (Mn) and weight-average molecular weight (Mw) of resins, polymers, or copolymers refer to standard polystyrene equivalent values ​​measured at 40°C by gel permeation chromatography (GPC) with tetrahydrofuran as the mobile phase.

[0022] In this disclosure, “solids” means the total mass of the components excluding the solvent (F), including (A) binder resin, (B1) first quinone diazide adduct, (B2) second quinone diazide adduct, (C) black coloring agent, and an optional dissolution accelerator (D) and an optional component (E).

[0023] [Photosensitive resin composition] A photosensitive resin composition according to one embodiment comprises (A) a binder resin, (B1) a first quinone diazide adduct which is a quinone diazide adduct to a first phenol compound, (B2) a second quinone diazide adduct which is a quinone diazide adduct to a second phenol compound different from the first phenol compound, and (C) a black coloring agent.

[0024] <Binder resin (A)> The binder resin (A) is not particularly limited, but it is preferable that it has alkali-soluble functional groups and is alkali-soluble. Examples of alkali-soluble functional groups are not particularly limited, but include carboxyl groups, phenolic hydroxyl groups, sulfo groups, phosphoric acid groups, acid anhydride groups, and mercapto groups. A binder resin having two or more types of alkali-soluble functional groups may also be used.

[0025] Examples of binder resins (A) include homopolymers or copolymers of polymerizable monomers having alkali-soluble functional groups, and resins having epoxy groups and phenolic hydroxyl groups. Examples of other binder resins (A) include acrylic resins, polystyrene resins, epoxy resins, polyamide resins, phenolic resins, polyimide resins, polyamic acid resins, polybenzoxazole resins, polybenzoxazole resin precursors, silicone resins, cyclic olefin polymers, cardo resins, and derivatives of these resins, as well as resins to which alkali-soluble functional groups are bonded. For example, as a derivative of phenolic resin, polyalkenylphenol resins in which alkenyl groups are bonded to a benzene ring are included, and as a derivative of polystyrene resin, hydroxypolystyrene resin derivatives in which phenolic hydroxyl groups and hydroxyalkyl groups or alkoxy groups are bonded to a benzene ring are included. These resins can be used individually or in combination of two or more types.

[0026] The binder resin (A) may have radical polymerizable functional groups. In one embodiment, the binder resin (A) has a (meth)acryloyloxy group, an allyl group, or a methallyl group as the radical polymerizable functional group.

[0027] The alkali-soluble functional groups of the binder resin (A), such as phenolic hydroxyl groups, may be partially or entirely protected by acid-degradable groups. The alkali solubility of the binder resin (A) protected by acid-degradable groups is suppressed before exposure. The quinone diazide adducts (B1) and (B2), described later, generate alkali-soluble carboxylic acid compounds when irradiated with radiation such as visible light, ultraviolet light, gamma rays, and electron beams. The generated carboxylic acid compounds promote the decomposition of the acid-degradable groups of the binder resin (A), regenerating the alkali-soluble functional groups and increasing the alkali solubility of the binder resin (A). As a result, the change in alkali solubility of the binder resin (A) before and after exposure (before and after decomposition of acid-degradable groups) becomes larger, and the resolution of the pattern can be further improved.

[0028] (Copolymer of a polymerizable monomer having an alkali-soluble functional group and other polymerizable monomers (a1)) In one embodiment, the binder resin (A) comprises a copolymer (a1) of a polymerizable monomer having an alkali-soluble functional group and another polymerizable monomer (also simply referred to in this disclosure as "alkali aqueous solution soluble copolymer (a1)"). Examples of alkali-soluble functional groups include carboxyl groups, phenolic hydroxyl groups, sulfo groups, phosphoric acid groups, acid anhydride groups, and mercapto groups. Examples of polymerizable functional groups of the polymerizable monomer include radical polymerizable functional groups, such as CH2=CH-, CH2=C(CH3)-, CH2=CHCO-, CH2=C(CH3)CO-, and -OC-CH=CH-CO-.

[0029] Alkaline aqueous solution soluble copolymer (a1) can be produced, for example, by radical polymerization of a polymerizable monomer having an alkali-soluble functional group and another polymerizable monomer. A derivative obtained by synthesizing a copolymer by radical polymerization and then adding an alkali-soluble functional group to the copolymer may also be used. Examples of polymerizable monomers having an alkali-soluble functional group include (meth)acrylic acid, α-bromo(meth)acrylic acid, α-chloro(meth)acrylic acid, β-furyl(meth)acrylic acid, β-styryl(meth)acrylic acid, maleic acid, monomethyl maleic acid, monoethyl maleic acid, monoisopropyl maleic acid, fumaric acid, cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid, 3-maleimidopropionic acid, 4-maleimidobutyric acid, 6-maleimidohexanoic acid, and other polymerizable monomers having a carboxyl group; 4-hydroxystyrene, 4-hydroxyphenyl Examples include polymerizable monomers having phenolic hydroxyl groups such as nyl(meth)acrylate, 3,5-dimethyl-4-hydroxybenzylacrylamide, 4-hydroxyphenylacrylamide, and 4-hydroxyphenylmaleimide; polymerizable monomers having sulfo groups such as (meth)allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, and styrenesulfonic acid; polymerizable monomers having phosphate groups such as mono(2-(meth)acryloyloxyethyl) phosphate; and polymerizable monomers having acid anhydride groups such as maleic anhydride, itaconic anhydride, and citraconic anhydride.Other polymerizable monomers include, for example, styrene derivatives such as styrene, vinyltoluene, α-methylstyrene, p-methylstyrene, and p-ethylstyrene; acrylamide; acrylonitrile; vinyl alcohol ether compounds such as vinyl-n-butyl ether; methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, and phenyl (meth)acrylate. Examples include (meth)acrylic acid esters such as tetrahydrofurfuryl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentanyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, and 2,2,3,3-tetrafluoropropyl (meth)acrylate; and N-substituted maleimides such as phenylmaleimide and cyclohexylmaleimide. From the viewpoint of heat resistance, etc., it is preferable that the alkaline aqueous solution soluble copolymer (a1) has one or more types of cyclic structures such as alicyclic structures, aromatic structures, polycyclic structures, inorganic cyclic structures, and heterocyclic structures.

[0030] The polymerizable monomer having an alkali-soluble functional group preferably has one or more cyclic structures. The polymerizable monomer having an alkali-soluble functional group preferably has a phenolic hydroxyl group. The polymerizable monomer having an alkali-soluble functional group preferably has at least one selected from the group consisting of (meth)acrylic compounds having CH2=CHCO- or CH2=C(CH3)CO- and maleimide compounds having -OC-CH=CH-CO- as the radical polymerizable functional group. The polymerizable monomer having an alkali-soluble functional group preferably has formula (1) after polymerization. [ka] It is more preferable that it forms a structural unit represented by the formula. In formula (1), R 1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a is an integer of 1 to 5. R 1 is preferably a hydrogen atom or a methyl group. a is preferably an integer of 1 to 3, and more preferably 1. As such a polymerizable monomer having an alkali-soluble functional group, 4-hydroxyphenyl methacrylate is particularly preferable.

[0031] As other polymerizable monomers, after polymerization, formula (2)

Chemical formula

[0032] The alkali aqueous solution-soluble copolymer (a1) has the formula (1) [ka] (In equation (1), R 1 (where a is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a is an integer from 1 to 5.) It is preferable that the structural units represented by are present.

[0033] Alkaline aqueous solution soluble copolymer (a1) is given by formula (2) [ka] (In equation (2), R 2 and R 3 Each of these is independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, a fully or partially fluorinated fluoroalkyl group having 1 to 3 carbon atoms, or a halogen atom, and R 4 This refers to a phenyl group substituted with a hydrogen atom, a linear alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 3 to 12 carbon atoms, a phenyl group, or at least one selected from the group consisting of a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, and an alkoxy group having 1 to 6 carbon atoms. It is preferable that the structural units represented by are present.

[0034] It is particularly preferable to use 4-hydroxyphenyl methacrylate as the polymerizable monomer having alkali-soluble functional groups, and phenyl maleimide or N-cyclohexyl maleimide as other polymerizable monomers. By using resins obtained by radical polymerization of these polymerizable monomers, shape retention and developability can be improved, and outgassing can be reduced.

[0035] When producing an alkaline aqueous solution soluble copolymer (a1) by radical polymerization, the polymerization initiator is not limited to the following, but includes azo polymerization initiators such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), dimethyl-2,2'-azobis(2-methylpropionate), 4,4'-azobis(4-cyanovaleric acid), and 2,2'-azobis(2,4-dimethylvaleronitrile) (AVN); dicumyl peroxide, 2,5-dimethyl-2,5-di( Peroxide polymerization initiators with a 10-hour half-life temperature of 100 to 170°C, such as tert-butylperoxy)hexane, tert-butylcumyl peroxide, di-tert-butyl peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, and cumene hydroperoxide, can be used. Alternatively, peroxide polymerization initiators such as benzoyl peroxide, lauroyl peroxide, 1,1'-di(tert-butylperoxy)cyclohexane, and tert-butylperoxypivalate can be used. The amount of polymerization initiator used is generally preferably 0.01 parts by mass or more, 0.05 parts by mass or more, 0.5 parts by mass or more, 40 parts by mass or less, 20 parts by mass or less, or 15 parts by mass or less, per 100 parts by mass of the total polymerizable monomers.

[0036] A RAFT (Reversible Addition Fragmentation Transfer) agent may be used in combination with a polymerization initiator. While not limited to the following, thiocarbonylthio compounds such as dithioesters, dithiocarbamates, trithiocarbonates, and xanthanthates can be used as RAFT agents. The RAFT agent can be used in an amount of 0.005 to 20 parts by mass, preferably 0.01 to 10 parts by mass, per 100 parts by mass of the total polymerizable monomers.

[0037] The weight-average molecular weight (Mw) of the alkali aqueous solution-soluble copolymer (a1) can be 3,000 to 80,000, preferably 4,000 to 70,000, and more preferably 5,000 to 60,000. The number-average molecular weight (Mn) can be 1,000 to 30,000, preferably 1,500 to 25,000, and more preferably 2,000 to 20,000. The polydispersity (Mw / Mn) can be 1.0 to 3.5, preferably 1.1 to 3.0, and more preferably 1.2 to 2.8. By setting the weight-average molecular weight, number-average molecular weight, and polydispersity within the above ranges, a photosensitive resin composition with excellent alkali solubility and developability can be obtained.

[0038] In one embodiment, the photosensitive resin composition contains 1% to 50% by mass, preferably 2% to 40% by mass, and more preferably 5% to 30% by mass, of an alkaline aqueous solution soluble copolymer (a1) based on 100% by mass of its solid content. When the content of the alkaline aqueous solution soluble copolymer (a1) is 1% by mass or more based on 100% by mass of the solid content, the dissolution of the exposed area can be promoted to achieve high sensitivity, and the stability and durability of the film after heat curing can be ensured. When the content of the alkaline aqueous solution soluble copolymer (a1) is 50% by mass or less based on 100% by mass of the solid content, the solubility of the unexposed area can be kept low, and the residual film rate can be maintained at a high level.

[0039] (Protective resin (a2)) The binder resin (A) may include a protective resin (a2) in which at least a portion of the alkali-soluble functional groups are protected by acid-degradable groups, with the above-mentioned alkali aqueous solution-soluble copolymer (a1) as the base resin. The protective resin (a2) exhibits a significant change in alkali solubility before and after exposure (before and after decomposition of acid-degradable groups), resulting in a higher resolution of the pattern. Acid generated during exposure catalytically promotes the decomposition (deprotection) of acid-degradable groups, regenerating phenolic hydroxyl groups. Post-exposure baking (PEB) may be performed after exposure as needed. This promotes the alkali dissolution of the protective resin (a2) in the exposed area during development. The protective resin (a2) can be used alone or in combination of two or more types. For example, the protective resin (a2) may be a combination of two or more resins with different polymer structural units, acid-degradable groups, protection rates of alkali-soluble functional groups, or combinations thereof.

[0040] In protective resin (a2), the alkali-soluble functional group is preferably a phenolic hydroxyl group. The alkali solubility of protective resin (a2) before exposure is suppressed because a portion of the phenolic hydroxyl group is protected by an acid-degradable group. The base resin of protective resin (a2) is preferably one having phenolic hydroxyl groups on a benzene ring pendanted to the polymer main chain. In a base resin of protective resin (a2) having this structure, the benzene ring with phenolic hydroxyl groups constitutes the polymer main chain, and compared to a novolac resin with equivalent hydroxyl value, alkali compounds in the developer solution can easily approach the phenolic hydroxyl groups, resulting in higher alkali solubility.

[0041] (Protection of phenolic hydroxyl groups by acid-degradable groups) In an embodiment in which the alkali-soluble functional group of the protective resin (a2) is a phenolic hydroxyl group, the protective resin (a2) can be obtained by using the above-mentioned alkali aqueous solution-soluble copolymer (a1) having a phenolic hydroxyl group as the base resin and protecting a portion of its phenolic hydroxyl groups with an acid-degradable group. The protective resin (a2) having a phenolic hydroxyl group protected with an acid-degradable group is Ar-OR 5It has a substructure where Ar represents an aromatic ring derived from phenol, and R 5 This represents an acid-degradable group.

[0042] Acid-degradable groups are groups that decompose (deprotect) in the presence of an acid, and optionally by heating, to generate alkali-soluble functional groups. Specifically, these include, for example, groups having tertiary alkyl groups such as tert-butyl group, 1,1-dimethylpropyl group, 1-methylcyclopentyl group, 1-ethylcyclopentyl group, 1-methylcyclohexyl group, 1-ethylcyclohexyl group, 1-methyladamantyl group, 1-ethyladamantyl group, tert-butoxycarbonyl group, and 1,1-dimethyl-propoxycarbonyl group; silyl groups such as trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, triisopropylsilyl group, and t-butyldiphenylsilyl group; and formula (3) -CR 6 R 7 -OR 8 (3) (In formula (3), R 6 and R 7 Each of these is independently a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms, or a branched alkyl group having 3 to 4 carbon atoms, and R 8 R is a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, a cyclic alkyl group having 3 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms. 6 or R 7 One of the two and R 8 They may combine to form a ring structure with 3 to 10 members, R 6 , R 7 and R 8 The group may be substituted with a halogen atom selected from the group consisting of fluorine, chlorine, bromine, and iodine.) The group represented by formula (3) forms an acetal structure or a ketal structure together with the oxygen atom derived from the phenolic hydroxyl group. These acid-degradable groups can be used alone or in combination of two or more types.

[0043] Since a highly sensitive photosensitive resin composition can be obtained even with low exposure, the acid-degradable group is preferably a group represented by formula (3). 6 and R 7 Each of these is independently a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms, or a branched alkyl group having 3 to 4 carbon atoms, and R 8 It is more preferably a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, or a cyclic alkyl group having 3 to 12 carbon atoms, which may be substituted with a halogen atom selected from the group consisting of fluorine, chlorine, bromine, and iodine. Examples of such acid-degradable groups include 1-alkoxyalkyl groups. Examples of 1-alkoxyalkyl groups include methoxymethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, 1-n-propoxyethyl group, 1-n-butoxyethyl group, 1-isobutoxyethyl group, 1-(2-chloroethoxy)ethyl group, 1-(2-ethylhexyloxy)ethyl group, 1-cyclohexyloxyethyl group, and 1-(2-cyclohexylethoxy)ethyl group, with 1-ethoxyethyl group and 1-n-propoxyethyl group being preferred. As an acid-degradable group, a group represented by formula (3) is R 6 or R 7 One of the two and R 8 A ring structure with 3 to 10 members formed by the bonding of these elements can also be suitably used. In this case, R, which is not involved in the formation of the ring structure, can also be used. 6 or R 7 It is preferable that the group is a hydrogen atom. Examples of such acid-degradable groups include the 2-tetrahydrofuranyl group and the 2-tetrahydropyranyl group, with the 2-tetrahydrofuranyl group being preferred.

[0044] The protection reaction of phenolic hydroxyl groups can be carried out under known conditions using common protective agents. For example, a protective resin (a2) can be obtained by reacting a base resin and a protective agent in the presence of an acid or base in a solvent-free environment or in a solvent such as toluene or hexane at a reaction temperature of -20 to 50°C.

[0045] As a protective agent, known protective agents capable of protecting phenolic hydroxyl groups can be used. For example, if the acid-degradable group is a tert-butyl group, isobutene can be used as a protective agent; if it is a tert-butoxycarbonyl group, di-tert-butyl dicarbonate can be used. If the acid-degradable group is a silyl group such as a trimethylsilyl group or a triethylsilyl group, silicon-containing chlorides such as trimethylsilyl chloride or triethylsilyl chloride, or silicon-containing triflate compounds such as trimethylsilyl triflate or triethylsilyl triflate can be used. If the acid-degradable group is a methoxymethyl group, chloromethyl methyl ether can be used; if it is a 1-ethoxyethyl group, ethyl vinyl ether can be used; if it is a 1-n-propoxyethyl group, n-propyl vinyl ether can be used; if it is a 2-tetrahydrofuranyl group, 2,3-dihydrofuran can be used; and if it is a 2-tetrahydropyranyl group, 3,4-dihydro-2H-pyran can be used.

[0046] Examples of acids include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and perchloric acid, and organic acids such as methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, and benzenesulfonic acid. Salts of organic acids, such as the pyridinium salt of p-toluenesulfonic acid, can also be used as acid sources. Examples of bases include inorganic hydroxides such as sodium hydroxide and potassium hydroxide, inorganic carbonates such as sodium carbonate, sodium bicarbonate, potassium carbonate, and cesium carbonate, metal hydrides such as sodium hydride, and amine compounds such as pyridine, N,N-dimethyl-4-aminopyridine, imidazole, triethylamine, and diisopropylethylamine.

[0047] In another embodiment, a protective resin (a2) can also be obtained by protecting the phenolic hydroxyl groups of a polymerizable monomer having phenolic hydroxyl groups with an acid-degradable group, and then polymerizing or copolymerizing the polymerizable monomer having phenolic hydroxyl groups protected with the acid-degradable group and, if necessary, other polymerizable monomers. The protection of the phenolic hydroxyl groups of the polymerizable monomer having phenolic hydroxyl groups can be carried out in the same manner as the protection of the phenolic hydroxyl groups of the base resin.

[0048] The protective resin (a2) is given by formula (4) [ka] (In equation (4), R 9 R is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 10 It is preferable that the structure has a structural unit represented by formula (4) where r is an acid-degradable group, r is an integer from 0 to 5, s is an integer from 0 to 5, and r+s is an integer from 1 to 5. 10 The acid-degradable group is preferably the group represented by formula (3) above.

[0049] The protective resin (a2) is given by formula (2) [ka] (In equation (2), R 2 and R 3 Each of these is independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, a fully or partially fluorinated fluoroalkyl group having 1 to 3 carbon atoms, or a halogen atom, and R 4 It is preferable that the structural unit represented by ) is a hydrogen atom, a linear alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 3 to 12 carbon atoms, a phenyl group, or a phenyl group substituted with at least one selected from the group consisting of a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, and an alkoxy group having 1 to 6 carbon atoms. 2 and R 3 Each of these is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. 4 It is preferably a phenyl group substituted with at least one selected from the group consisting of a cyclic alkyl group having 3 to 12 carbon atoms, a phenyl group, or a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, and an alkoxy group having 1 to 6 carbon atoms, and more preferably a cyclic alkyl group having 3 to 12 carbon atoms or a phenyl group.

[0050] In one embodiment, the number of structural units represented by formula (4) where s is an integer of 1 or more, i.e., structural units represented by formula (4) in which at least one phenolic hydroxyl group is protected by an acid-degradable group, is 5% to 95%, preferably 15% to 70%, and more preferably 25% to 60%, of the total number of structural units in the protective resin (a2). By setting the proportion of the above structural units to 5% or more, a chemical amplification function can be imparted to the photosensitive resin composition, thereby achieving high sensitivity. By setting the proportion of the above structural units to 95% or less, the amount of unreacted acid-degradable groups remaining can be reduced, improving the solubility of the exposed area and achieving high sensitivity.

[0051] In one embodiment, the photosensitive resin composition contains 5% to 50% by mass, preferably 10% to 40% by mass, and more preferably 15% to 30% by mass, of the protective resin (a2) based on 100% by mass of solids. When the content of the protective resin (a2) is 5% by mass or more based on 100% by mass of solids, the dissolution of the exposed area can be promoted, creating a difference in solubility between the unexposed and exposed areas, thereby achieving high sensitivity and ensuring the stability and durability of the film after heat curing. When the content of the protective resin (a2) is 50% by mass or less based on 100% by mass of solids, the solubility of the unexposed area can be kept low, maintaining a high residual film rate.

[0052] (Resin having epoxy groups and phenolic hydroxyl groups (a3)) The binder resin (A) may contain a resin (a3) ​​having epoxy groups and phenolic hydroxyl groups. The resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is an alkaline aqueous solution soluble resin. The resin (a3) ​​having epoxy groups and phenolic hydroxyl groups may also have alkali-soluble functional groups other than phenolic hydroxyl groups. The phenolic hydroxyl groups and other alkali-soluble functional groups may be protected by acid-degradable groups. The resin (a3) ​​having epoxy groups and phenolic hydroxyl groups can be obtained, for example, by reacting some of the epoxy groups of a compound having at least two epoxy groups in one molecule (hereinafter sometimes referred to as "epoxy compound") with the carboxyl group of a hydroxybenzoic acid compound. The epoxy groups of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups form crosslinks by reaction with phenolic hydroxyl groups during post-baking heat treatment after development, thereby improving the chemical resistance, heat resistance, etc. of the coating. Since phenolic hydroxyl groups contribute to solubility in alkaline aqueous solutions during development, the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups also functions as a dissolution accelerator for binder resin (A) whose acid-degradable groups were not sufficiently decomposed (deprotected) when exposed at low exposure levels, thereby making the photosensitive resin composition highly sensitive.

[0053] Reaction Equation 1 below shows an example of a reaction in which one of the epoxy groups of an epoxy compound reacts with the carboxyl group of a hydroxybenzoic acid compound to form a compound having a phenolic hydroxyl group. [ka]

[0054] Examples of compounds having at least two epoxy groups in one molecule include novolac epoxy resins such as phenol novolac epoxy resins and cresol novolac epoxy resins, bisphenol epoxy resins, biphenol epoxy resins, naphthalene skeleton-containing epoxy resins, alicyclic epoxy resins, and heterocyclic epoxy resins. These epoxy compounds only need to have two or more epoxy groups in one molecule and can be used alone or in combination of two or more types. Since these compounds are thermosetting, it is common knowledge to those skilled in the art that their structure cannot be uniquely described based on differences such as the presence or absence of epoxy groups, the type of functional group, and the degree of polymerization. An example of the structure of a novolac epoxy resin is shown in formula (6). In formula (6), for example, R 14 m is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 2 carbon atoms, or a hydroxyl group, and m is an integer from 1 to 50. [ka]

[0055] Examples of phenol novolac type epoxy resins include EPICLON® N-770 (manufactured by DIC Corporation) and jER®-152 (manufactured by Mitsubishi Chemical Corporation). Examples of cresol novolac type epoxy resins include EPICLON® N-695 (manufactured by DIC Corporation) and EOCN®-102S (manufactured by Nippon Kayaku Co., Ltd.). Examples of bisphenol type epoxy resins include bisphenol A type epoxy resins such as jER® 828, jER® 1001 (manufactured by Mitsubishi Chemical Corporation) and YD-128 (trade name, manufactured by Nippon Steel Chemical & Material Co., Ltd.), and bisphenol F type epoxy resins such as jER® 806 (manufactured by Mitsubishi Chemical Corporation) and YDF-170 (trade name, manufactured by Nippon Steel Chemical & Material Co., Ltd.). Examples of biphenol-type epoxy resins include jER(registered trademark) YX-4000 and jER(registered trademark) YL-6121H (manufactured by Mitsubishi Chemical Corporation). Examples of naphthalene skeleton-containing epoxy resins include NC-7000 (trade name, manufactured by Nippon Kayaku Co., Ltd.) and EXA-4750 (trade name, manufactured by DIC Corporation). Examples of alicyclic epoxy resins include EHPE(registered trademark)-3150 (manufactured by Daicel Chemical Industries, Ltd.). Examples of heterocyclic epoxy resins include TEPIC(registered trademark), TEPIC-L, TEPIC-H, and TEPIC-S (manufactured by Nissan Chemical Industries, Ltd.).

[0056] The compound having at least two epoxy groups in one molecule is preferably a novolac-type epoxy resin, and more preferably at least one selected from the group consisting of phenol novolac-type epoxy resins and cresol novolac-type epoxy resins. The photosensitive resin composition containing a resin (a3) ​​having epoxy groups derived from a novolac-type epoxy resin and phenolic hydroxyl groups exhibits excellent pattern-forming properties, easy adjustment of alkali solubility, and low outgassing.

[0057] Hydroxybenzoic acid compounds are compounds in which at least one of the 2-6 positions of benzoic acid is substituted with a hydroxyl group. Examples include salicylic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 2-hydroxy-5-nitrobenzoic acid, 3-hydroxy-4-nitrobenzoic acid, and 4-hydroxy-3-nitrobenzoic acid. Dihydroxybenzoic acid compounds are preferred in that they enhance alkali developability. Hydroxybenzoic acid compounds can be used alone or in combination of two or more types.

[0058] In one embodiment, the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is a reaction product of a compound having at least two epoxy groups in one molecule and a hydroxybenzoic acid compound, and formula (7) [ka] It has the following structure. In formula (7), b is an integer from 1 to 5, and * represents the binding site with the residue excluding the epoxy group involved in the reaction, in a compound having at least two epoxy groups in one molecule.

[0059] In the method for obtaining a resin (a3) ​​having epoxy groups and phenolic hydroxyl groups from an epoxy compound and a hydroxybenzoic acid compound, 0.2 to 0.95 equivalents of the hydroxybenzoic acid compound can be used per 1 equivalent of epoxy groups in the epoxy compound, preferably 0.3 to 0.9 equivalents, and more preferably 0.4 to 0.8 equivalents. If the amount of hydroxybenzoic acid compound is 0.2 equivalents or more, sufficient alkaline solubility can be obtained, and if it is 0.95 equivalents or less, the increase in molecular weight due to side reactions can be suppressed.

[0060] A catalyst may be used to accelerate the reaction between the epoxy compound and the hydroxybenzoic acid compound. The amount of catalyst used can be 0.1 to 10 parts by mass based on 100 parts by mass of the reaction material mixture consisting of the epoxy compound and the hydroxybenzoic acid compound. The reaction temperature can be 60 to 150°C, and the reaction time can be 3 to 30 hours. Examples of catalysts used in this reaction include triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, chromium octanoate, and zirconium octanoate.

[0061] The number-average molecular weight (Mn) of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is preferably 500 to 8000, more preferably 800 to 6000, and even more preferably 1000 to 5000. If the number-average molecular weight is 500 or more, it has appropriate alkali solubility and is therefore good as a resin for photosensitive materials, and if it is 8000 or less, it has good coating properties and developability.

[0062] In one embodiment, the epoxy equivalent of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 300 to 7000, preferably 400 to 6000, and more preferably 500 to 5000. If the epoxy equivalent of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 300 or more, sufficient alkali solubility can be imparted to the resin (a3). If the epoxy equivalent of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 7000 or less, the strength of the cured film can be increased. The epoxy equivalent is determined according to JIS K 7236:2009.

[0063] In one embodiment, the hydroxyl equivalent of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 160 to 500, preferably 170 to 400, and more preferably 180 to 300. If the hydroxyl equivalent of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 160 or more, the strength of the cured film can be increased. If the hydroxyl equivalent of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 500 or less, sufficient alkali solubility can be imparted to the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups. The hydroxyl equivalent is determined according to JIS K 0070:1992.

[0064] In one embodiment, the photosensitive resin composition contains 5% to 50% by mass, preferably 10% to 40% by mass, and more preferably 15% to 30% by mass, of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups, based on 100% by mass of solids. When the content of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 5% by mass or more based on 100% by mass of solids, the dissolution of the exposed area can be promoted to achieve high sensitivity, and the stability and durability of the film after heat curing can be ensured. When the content of the resin (a3) ​​having epoxy groups and phenolic hydroxyl groups is 50% by mass or less based on 100% by mass of solids, the solubility of the unexposed area can be kept low, and the residual film rate can be maintained at a high level.

[0065] <First quinone diazide adduct (B1) and second quinone diazide adduct (B2)> The photosensitive resin composition includes, as a radiation-sensitive compound, quinone diazide adducts of at least two types of phenol compounds, namely, a first quinone diazide adduct (B1) which is a quinone diazide adduct to a first phenol compound, and a second quinone diazide adduct (B2) which is a quinone diazide adduct to a second phenol compound other than the first quinone diazide adduct (B1). In this disclosure, the first quinone diazide adduct (B1) and the second quinone diazide adduct (B2) are collectively referred to as quinone diazide adduct (B). Similarly, in this disclosure, the first phenol compound and the second phenol compound are collectively referred to as phenol compounds. For example, in the case of a quinone diazide adduct (B) having a trivalent phenol compound represented by formula (8) as its backbone, [ka] This refers to the compounds described below in which at least one of the three phenolic hydroxyl groups of a phenol compound is substituted with a group having a quinone diazide structure, such as the naphthoquinone diazidesulfonate group shown below. Substitution with a naphthoquinone diazidesulfonate group can be carried out by esterifying (sulfonating) the phenolic hydroxyl group of the phenol compound with a quinone diazidesulfonic acid halide.

[0066] [ka]

[0067] In the above structural formula, each R is independently a hydrogen atom. [ka] or [ka] It represents.

[0068] When irradiated with ultraviolet light or the like, the quinone diazide adduct (B) generates a carboxyl group via the reaction shown in reaction equation 2 below. The generation of the carboxyl group makes the exposed portion (film) soluble in an alkaline aqueous solution, and thus alkaline developability is acquired in that portion.

[0069] [ka]

[0070] The inventors have found that by using a first quinone diazide adduct (B1), which is a quinone diazide adduct to a first phenol compound, and a second quinone diazide adduct (B2), which is a quinone diazide adduct to a second phenol compound, as the radiation-sensitive compounds, and by setting the difference in molecular weight between the first phenol compound and the second phenol compound to 40-500, preferably 42-400, and more preferably 45-350, the sensitivity of the photosensitive resin composition can be increased while maintaining pattern-forming properties. Here, the molecular weight of the first phenol compound constituting the first quinone diazide adduct (B1) is smaller than the molecular weight of the second phenol compound constituting the second quinone diazide adduct (B2). Although not bound by any theory, a quinone diazide adduct to a first phenol compound with a lower molecular weight (first quinone diazide adduct (B1)) improves the solubility of the exposed area compared to a quinone diazide adduct to a second phenol compound with a higher molecular weight (second quinone diazide adduct (B2)). The second quinone diazide adduct (B2) suppresses excessive dissolution of unexposed areas during development, while dissolving in exposed areas by generating a carboxylic acid compound similar to the first quinone diazide adduct (B1). Therefore, by using the first quinone diazide adduct (B1) and the second quinone diazide adduct (B2) in combination, it is possible to enhance the sensitivity of the photosensitive resin composition while maintaining pattern formation properties. The present invention has technical significance in that it increases the design freedom of photosensitive resin compositions by demonstrating that, as a means of adjusting the sensitivity of a photosensitive resin composition, not only the type and composition of the binder resin and additives such as dissolution accelerators, but also quinone diazide adducts (B), which are radiation-sensitive compounds, can be used.

[0071] Examples of phenol compounds include Bis-Z, BisP-EZ, TekP-4HBPA, TrisP-HAP, TrisP-PA, TrisP-SA, TrisOCR-PA, BisOCHP-Z, BisP-MZ, BisP-PZ, BisP-IPZ, BisOCP-IPZ, BisP-CP, BisRS-2P, BisRS-3P, BisP-OCHP, Methylenethris-FR-CR, BisRS-26X, DML-MBPC, DML-MBOC, DML-OCHP, DML-PCHP, DML-PC, DML-PTBP, DML-34X, DML-EP, DML-POP, Dimethylol-BisOC-P, DML-PFP, DML-PSBP, DML-MT Examples include, but are not limited to, risPC, TriML-P, TriML-35XL, TML-BP, TML-HQ, TML-pp-BPF, TML-BPA, TMOM-BP, HML-TPPHBA, HML-TPHAP (all trade names, manufactured by Honshu Chemical Industry Co., Ltd.), 2,6-bis(methoxymethyl)-4-tert-butylphenol, 2,6-bis(methoxymethyl)-p-cresol, 2,6-bis(acetoxymethyl)-p-cresol, naphthol, trihydroxybenzophenone, tetrahydroxybenzophenone, bisphenol A, bisphenol E, methylenebisphenol, and BisP-AP (trade names, manufactured by Honshu Chemical Industry Co., Ltd.). The first and second phenol compounds can be selected in combination to achieve a predetermined molecular weight difference.

[0072] Preferably, the first phenol compound and the second phenol compound each have three or more phenolic hydroxyl groups. The first quinone diazide adduct (B1) and the second quinone diazide adduct (B2) obtained from the phenol compound having three or more phenolic hydroxyl groups have a high level of balance between photosensitivity and solubility, and therefore can improve the sensitivity of the photosensitive resin composition.

[0073] The molecular weight of the first phenol compound is preferably 230 or more and less than 300, more preferably 230 or more and 280 or less, and even more preferably 230 or more and 260 or less. A molecular weight of 230 or more for the first phenol compound suppresses excessive dissolution of the unexposed areas and allows for a difference in solubility between the unexposed and exposed areas. A molecular weight of less than 300 for the first phenol compound maximizes the solubility of the exposed areas.

[0074] The molecular weight of the second phenol compound is preferably 300 to 600, more preferably 300 to 590, and even more preferably 300 to 580. A molecular weight of 300 or more for the second phenol compound suppresses excessive dissolution of the unexposed areas, creating a difference in solubility between the unexposed and exposed areas. A molecular weight of 600 or less for the second phenol compound suppresses residue in the exposed areas, resulting in good pattern formation.

[0075] Suitable phenol compounds include, for example, those having the following structural formula. [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0076] The quinone diazide adduct (B) can be obtained, for example, by esterifying the phenolic hydroxyl group of a phenol compound with a compound represented by formula (9) or (10). [ka] [ka]

[0077] In equations (9) and (10), R a ~R d Each of these independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and X represents a halogen atom or OH.

[0078] R a ~R d Each of these is preferably independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a methyl group, or a methoxy group, and even more preferably a hydrogen atom. X is preferably a chlorine atom. Examples of compounds represented by formulas (9) and (10) include 1,2-naphthoquinone diazide-4-sulfonic acid chloride and 1,2-naphthoquinone diazide-5-sulfonic acid chloride, with 1,2-naphthoquinone diazide-5-sulfonic acid chloride being preferred.

[0079] In one embodiment, the quinone diazide adduct (B) is obtained in which the phenolic hydroxyl group of the phenol compound is replaced with a group having a quinone diazide structure represented by formula (11) or formula (12).

[0080] [ka] [ka]

[0081] In equations (11) and (12), R a~R d Each of the following independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and * represents the bond between the phenolic hydroxyl group of a phenol compound and the oxygen atom. a ~R d Each of these is preferably independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a methyl group, or a methoxy group, and even more preferably a hydrogen atom.

[0082] The first quinone diazide adduct (B1) and the second quinone diazide adduct (B2) each preferably independently contain a 1,2-naphthoquinone diazide-4-sulfonic acid ester or a 1,2-naphthoquinone diazide-5-sulfonic acid ester of a phenol compound, and more preferably a 1,2-naphthoquinone diazide-4-sulfonic acid ester or a 1,2-naphthoquinone diazide-5-sulfonic acid ester of a phenol compound. The first quinone diazide adduct (B1) and the second quinone diazide adduct (B2) each may independently have both a 1,2-naphthoquinone diazide-4-sulfonic acid ester bond and a 1,2-naphthoquinone diazide-5-sulfonic acid ester bond in a single molecule. In one embodiment, the quinone diazide adduct (B) is a 1,2-naphthoquinone diazide-4-sulfonic acid ester. In another embodiment, the quinone diazide adduct (B) is 1,2-naphthoquinone diazide-5-sulfonic acid ester.

[0083] The degree of substitution in the quinone diazide adduct (B) (the percentage of the phenolic hydroxyl groups of the phenol compound that are substituted with groups having a quinone diazide structure, based on the total molecule of the quinone diazide adduct (B)) is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. By setting the degree of substitution to 20 mol% or more, the difference in solubility between the unexposed and exposed portions can be increased. The degree of substitution may be 100 mol% or less, 95 mol% or less, or 93 mol% or less.

[0084] The degree of substitution in the first quinone diazide adduct (B1) (the percentage of the phenolic hydroxyl groups of the first phenol compound that are substituted with groups having a quinone diazide structure, based on the total molecule of the quinone diazide adduct (B1)) is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. By setting the degree of substitution to 20 mol% or more, the difference in solubility between the unexposed and exposed portions can be increased. The degree of substitution may be 100 mol% or less, 95 mol% or less, or 93 mol% or less.

[0085] The degree of substitution in the second quinone diazide adduct (B2) (the percentage of the phenolic hydroxyl groups of the second phenol compound that are substituted with groups having a quinone diazide structure, based on the total molecule of the quinone diazide adduct (B2)) is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. By setting the degree of substitution to 20 mol% or more, the difference in solubility between the unexposed and exposed portions can be increased. The degree of substitution may be 100 mol% or less, 95 mol% or less, or 93 mol% or less.

[0086] The degree of substitution in the first quinone diazide adduct (B1) is preferably equal to or greater than the degree of substitution in the second quinone diazide adduct (B2).

[0087] The phenolic hydroxyl group equivalent of the first quinone diazide adduct (B1) is preferably 100 to 1500, more preferably 130 to 1400, and even more preferably 140 to 1300. By setting the phenolic hydroxyl group equivalent of the first quinone diazide adduct (B1) to 100 or more, the dissolution of the unexposed areas can be suppressed. By setting the phenolic hydroxyl group equivalent of the first quinone diazide adduct (B1) to 1500 or less, sufficient solubility can be imparted to the exposed areas after photosensitization.

[0088] The phenolic hydroxyl group equivalent of the second quinone diazide adduct (B2) is preferably 180 to 800, more preferably 180 to 700, and even more preferably 180 to 600. By setting the phenolic hydroxyl group equivalent of the second quinone diazide adduct (B2) to 180 or more, the dissolution of the unexposed areas can be suppressed. By setting the phenolic hydroxyl group equivalent of the second quinone diazide adduct (B2) to 800 or less, sufficient solubility can be imparted to the exposed areas after photosensitization.

[0089] The average number of phenolic hydroxyl groups in the first quinone diazide adduct (B1) is preferably 0.1 to 3.0, more preferably 0.2 to 2.5, and even more preferably 0.2 to 2.0 per molecule. By setting the average number of phenolic hydroxyl groups in the first quinone diazide adduct (B1) to 0.1 or more, sufficient solubility can be imparted to the exposed area after photosensitivity. By setting the average number of phenolic hydroxyl groups in the first quinone diazide adduct (B1) to 3.0 or less, dissolution of the unexposed area can be suppressed.

[0090] The average number of phenolic hydroxyl groups in the second quinone diazide adduct (B2) is preferably 0.5 to 5.0, more preferably 1.0 to 4.5, and even more preferably 1.0 to 4.0 per molecule. By setting the average number of phenolic hydroxyl groups in the second quinone diazide adduct (B2) to 0.5 or more, sufficient solubility can be imparted to the exposed area after photosensitization. By setting the average number of phenolic hydroxyl groups in the second quinone diazide adduct (B2) to 5.0 or less, dissolution of the unexposed area can be suppressed.

[0091] The photosensitive resin composition preferably contains 5 to 70 parts by mass, more preferably 8 to 60 parts by mass, and even more preferably 10 to 50 parts by mass of the first quinone diazide adduct (B1) based on 100 parts by mass of the binder resin (A). High sensitivity can be achieved if the content of the first quinone diazide adduct (B1) is 5 parts by mass or more based on 100 parts by mass of the binder resin (A). Good alkali developability is achieved if the content of the first quinone diazide adduct (B1) is 70 parts by mass or less based on 100 parts by mass of the binder resin (A).

[0092] The photosensitive resin composition preferably contains 5 to 70 parts by mass, more preferably 8 to 60 parts by mass, and even more preferably 10 to 50 parts by mass of a second quinone diazide adduct (B2) based on 100 parts by mass of binder resin (A). High sensitivity can be achieved if the content of the second quinone diazide adduct (B2) is 5 parts by mass or more based on 100 parts by mass of binder resin (A). Good alkali developability is achieved if the content of the second quinone diazide adduct (B2) is 70 parts by mass or less based on 100 parts by mass of binder resin (A).

[0093] The mass ratio of the first quinone diazide adduct (B1) to the second quinone diazide adduct (B2) (mass of the first quinone diazide adduct:mass of the second quinone diazide adduct) is preferably 1:13 to 13:1, more preferably 1:10 to 10:1, and even more preferably 1:8 to 8:1. By setting the above mass ratio to 1:13 to 13:1, the sensitivity of the photosensitive resin composition can be improved.

[0094] While not bound by any particular theory, in embodiments where the binder resin (A) includes a protective resin (a2), the carboxylic acid compound generated from the quinone diazide adduct promotes the decomposition of the acid-degradable groups of the protective resin (a2), regenerating alkali-soluble functional groups, such as phenolic hydroxyl groups, and increasing the alkali solubility of the protective resin (a2). Before photosensitivity, the quinone diazide adduct interacts with the alkali-soluble functional groups of the binder resin (e.g., by hydrogen bonding), rendering the binder resin insoluble in an alkaline aqueous solution. On the other hand, the presence of an alkali-soluble carboxylic acid compound in the irradiated area makes the resin in that area more easily soluble in the alkaline aqueous solution together with the carboxylic acid compound. Furthermore, the carboxylic acid compound has a relatively larger molecular structure than acids produced from photoacid generators commonly used in chemical amplification resists, such as p-toluenesulfonic acid and 1-propanesulfonic acid, and is less likely to diffuse in the film. As a result of these synergistic effects, the difference in alkali solubility between the unexposed and exposed areas can be greatly increased, which is thought to enable the formation of highly sensitive and high-resolution patterns even with low exposure levels.

[0095] In embodiments where the binder resin (A) includes a protective resin (a2), high-resolution patterns can be formed without the need for post-exposure heating (PEB), which is generally required for chemically amplified resists. The quinone diazide adduct has a relatively high quantum yield, and carboxylic acid compounds are efficiently generated in the exposed areas. If acid-degradable groups that can be decomposed by carboxylic acid compounds are present in the surrounding area, the generated carboxylic acid compounds decompose the acid-degradable groups even at room temperature, regenerating alkali-soluble functional groups, such as phenolic hydroxyl groups. As a result, the difference in alkali solubility between the unexposed and exposed areas can be increased. By omitting PEB, the decrease in pattern formation performance caused by excessive diffusion of acid generated from the photoacid generator into the unexposed areas under the high-temperature environment of PEB can be suppressed. Furthermore, if the binder resin (A) contains a resin (a3) ​​having epoxy groups and phenolic hydroxyl groups, omitting PEB prevents ring-opening polymerization of the epoxy groups of the resin (a3), thus maintaining the alkali solubility of the resin (a3) ​​during development.

[0096] <Black coloring agent (C)> As the black coloring agent (C), at least one selected from the group consisting of black dyes and black pigments can be used. Black dyes and black pigments may also be used in combination. For example, by forming a black partition on an organic EL element using a photosensitive resin composition containing the black coloring agent (C), the visibility of a display device such as an organic EL display can be improved.

[0097] In one embodiment, the black coloring agent (C) includes a black dye. As the black dye, dyes defined by the color index (CI) of Solvent Black 27 to 47 can be used. Preferably, the black dye is one defined by the CI of Solvent Black 27, 29, or 34. When at least one of the dyes defined by the CI of Solvent Black 27 to 47 is used as the black dye, the light-shielding properties of the film of the cured photosensitive resin composition can be maintained. Compared to a photosensitive resin composition containing a black pigment, a photosensitive resin composition containing a black dye leaves less residue of the black coloring agent (C) during development and can form a high-definition pattern on the film.

[0098] A black pigment may be used as the black coloring agent (C). Examples of black pigments include carbon black, carbon nanotubes, acetylene black, graphite, iron black, aniline black, titanium black, perylene pigments, and lactam pigments. Surface-treated versions of these black pigments can also be used. Examples of commercially available perylene pigments include BASF's K0084, K0086, Pigment Black 21, 30, 31, 32, 33, and 34. An example of a commercially available lactam pigment is BASF's Irgaphor® Black S0100CF. Due to its high light-shielding properties, the black pigment is preferably at least one selected from the group consisting of carbon black, titanium black, perylene pigments, and lactam pigments.

[0099] In one embodiment, the photosensitive resin composition contains 10 to 150 parts by mass, preferably 30 to 100 parts by mass, and more preferably 40 to 70 parts by mass, of a black coloring agent (C) based on 100 parts by mass of binder resin. If the content of the black coloring agent (C) is 10 parts by mass or more based on the above total of 100 parts by mass, the light-shielding properties of the cured film can be maintained. If the content of the black coloring agent (C) is 150 parts by mass or less based on the above total of 100 parts by mass, the film can be colored without impairing alkali developability.

[0100] <Dissolution accelerator (D)> The photosensitive resin composition may further contain a dissolution accelerator (D) to improve the solubility of the alkali-soluble portion in the developer during development. Examples of dissolution accelerator (D) include organic low molecular weight compounds selected from the group consisting of compounds having a carboxyl group and compounds having a phenolic hydroxyl group. Dissolution accelerator (D) can be used alone or in combination of two or more types.

[0101] In this disclosure, "low molecular weight compound" refers to a compound with a molecular weight of 1000 or less. The above organic low molecular weight compound has a carboxyl group and / or a phenolic hydroxyl group and is alkali soluble. The above organic low molecular weight compound may have only a carboxyl group, only a phenolic hydroxyl group, or both a carboxyl group and a phenolic hydroxyl group. Preferably, the total number of carboxyl groups and phenolic hydroxyl groups contained in one molecule of the above organic low molecular weight compound is 2 or more.

[0102] Examples of such low-molecular-weight organic compounds include: aliphatic monocarboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, caproic acid, diethylacetic acid, enanthic acid, and caprylic acid; aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, brassic acid, methylmalonic acid, ethylmalonic acid, dimethylmalonic acid, methylsuccinic acid, tetramethylsuccinic acid, and citraconic acid; aliphatic tricarboxylic acids such as tricarbaryl acid, aconitic acid, and camphoronic acid; and aromatic monocarboxylic acids such as benzoic acid, toluic acid, cumic acid, hemimeric acid, and mesitylene acid. Examples include aromatic polycarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid, merophanic acid, and pyromellitic acid; aromatic hydroxycarboxylic acids such as dihydroxybenzoic acid, trihydroxybenzoic acid, and gallic acid; other carboxylic acids such as phenylacetic acid, hydroatropic acid, hydrocinnamic acid, mandelic acid, phenylsuccinic acid, atropic acid, cinnamic acid, methyl cinnamate, benzyl cinnamate, cinnamyridene acetate, coumaric acid, and umbellic acid; and aromatic polyols such as catechol, resorcinol, hydroquinone, 1,2,4-benzenetriol, pyrogallol, phloroglucinol, and bisphenol.

[0103] The content of the dissolution accelerator (D) in the photosensitive resin composition can be 0.1 parts by mass to 50 parts by mass, preferably 1 to 35 parts by mass, and more preferably 2 to 20 parts by mass, based on 100 parts by mass of the binder resin. If the content of the dissolution accelerator (D) is 0.1 parts by mass or more based on the total 100 parts by mass, the dissolution of the resin components can be effectively promoted, and if it is 50 parts by mass or less, excessive dissolution of the resin components can be suppressed, thereby improving the pattern formation properties and surface quality of the coating.

[0104] <Optional component (E)> The photosensitive resin composition may include, as an optional component (E), a thermosetting agent, a surfactant, a colorant other than the black colorant (C), etc. In this disclosure, optional component (E) is defined as any component that does not fall under any of (A) to (D).

[0105] A thermal radical generator can be used as a thermosetting agent. Preferred thermal radical generators include organic peroxides, specifically organic peroxides with a 10-hour half-life temperature of 100 to 170°C, such as dicumyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, tert-butylcumyl peroxide, di-tert-butyl peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, and cumene hydroperoxide.

[0106] The content of the thermosetting agent is preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less, based on 100 parts by mass of the total solid content excluding the thermosetting agent.

[0107] The photosensitive resin composition may contain surfactants, for example, to improve coating properties, improve the smoothness of the film, or improve the developability of the film. Examples of surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene aryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; and Megafac (registered trademark). Examples include fluorinated surfactants such as F-251, F-281, F-430, F-444, R-40, F-553, F-554, F-555, F-556, F-557, F-558, F-559 (all trade names, manufactured by DIC Corporation), and Surflon® S-242, S-243, S-386, S-420, S-611 (all trade names, manufactured by AGC Seimi Chemical Co., Ltd.); and organosiloxane polymers KP323, KP326, and KP341 (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.). These surfactants can be used individually or in combination of two or more types.

[0108] The surfactant content is preferably 2 parts by mass or less, more preferably 1 part by mass or less, and even more preferably 0.5 parts by mass or less, based on 100 parts by mass of the total solid content excluding the surfactant.

[0109] The photosensitive resin composition may contain a second coloring agent other than the black coloring agent (C). Examples of the second coloring agent include dyes, organic pigments, and inorganic pigments. The second coloring agent can be used according to the purpose. The second coloring agent can be used in a content that does not impair the effects disclosed in the present invention.

[0110] Examples of dyes include azo dyes, benzoquinone dyes, naphthoquinone dyes, anthraquinone dyes, cyanine dyes, squarylium dyes, croconium dyes, merocyanine dyes, stilbene dyes, diphenylmethane dyes, triphenylmethane dyes, fluorane dyes, spiropyran dyes, phthalocyanine dyes, indigo dyes, fulgide dyes, nickel complex dyes, and azulene dyes. Among the dyes, red dyes are preferred. Examples of red dyes include VALIFAST® RED 3312 (a red dye defined by the CI of Solvent Red 122, manufactured by Orient Chemical Industry Co., Ltd.) and VALIFAST® RED 3311 (a red dye defined by the CI of Solvent Red 8, manufactured by Orient Chemical Industry Co., Ltd.).

[0111] Examples of pigments include CI Pigment Yellow 20, 24, 86, 93, 109, 110, 117, 125, 137, 138, 147, 148, 153, 154, 166; CI Pigment Orange 36, 43, 51, 55, 59, 61; CI Pigment Red 9, 97, 122, 123, 149, 168, 177, 180, 192, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240; CI Pigment Violet 19, 23, 29, 30, 37, 40, 50; CI Pigment Blue 15, 15:1, 15:4, 22, 60, 64; CI Pigment Green 7; and CI Pigment Brown 23, 25, 26.

[0112] [Coating composition] <Solvent (F)> The photosensitive resin composition can be dissolved in a solvent (F) and used as a coating composition in solution form (however, if a black pigment is included, the pigment is dispersed). For example, a coating composition containing the photosensitive resin composition can be prepared by dissolving a binder resin (A) in a solvent (F) to obtain a solution, and then mixing a first quinone diazide adduct (B1), a second quinone diazide adduct (B2), a black coloring agent (C), and optionally an optional component (E) such as a dissolution accelerator (D), a thermosetting agent, or a surfactant in predetermined proportions. The viscosity of the coating composition can be adjusted to suit the application method by changing the amount of solvent (F).

[0113] Examples of solvents (F) include glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol methyl ethyl ether, and ethylene glycol monoethyl ether; ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate; diethylene glycol compounds such as diethylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether; and propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate. Examples of solvents include tate compounds; aromatic hydrocarbons such as toluene and xylene; ketones such as methyl ethyl ketone, methyl amyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, and cyclohexanone; esters such as ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyethyl acetate, ethyl hydroxyethyl acetate, methyl 2-hydroxy-2-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, and γ-butyrolactone; and amide compounds such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents can be used individually or in combination of two or more.

[0114] The solid content concentration of the coating composition can be appropriately determined depending on the intended use. For example, the solid content concentration of the coating composition may be 1 to 60% by mass, 3 to 50% by mass, or 5 to 40% by mass.

[0115] When using pigments, known methods can be used for dispersion and mixing. For example, ball-type devices such as ball mills, sand mills, bead mills, paint shakers, and rocking mills; blade-type devices such as kneaders, paddle mixers, planetary mixers, and Henschel mixers; roll-type devices such as three-roll mixers; and other devices such as lithographs, colloid mills, ultrasonic devices, homogenizers, and rotational / revolutionary mixers may be used. From the viewpoint of dispersion efficiency and fine dispersion, it is preferable to use a bead mill.

[0116] The prepared coating composition is usually filtered before use. Examples of filtration methods include Millipore filters with a pore size of 0.05 to 1.0 μm.

[0117] The coating composition prepared in this way also exhibits excellent long-term storage stability.

[0118] [Method of using the photosensitive resin composition] When using a photosensitive resin composition in radiation lithography, first, the photosensitive resin composition is dissolved or dispersed in a solvent to prepare a coating composition. Next, the coating composition can be applied to the substrate surface, and the solvent can be removed by means of heating or other means to form a film. The method of applying the coating composition to the substrate surface is not particularly limited, and for example, a spray method, roll coating method, slit method, or spin coating method can be used.

[0119] After applying the coating composition to the substrate surface, the solvent is usually removed by heating to form a film (pre-baking). The heating conditions vary depending on the type and proportion of each component, but typically a temperature of 70-130°C is used. For example, the film can be obtained by heating on a hot plate for 30 seconds to 20 minutes, or in an oven for 1 to 60 minutes.

[0120] Next, the pre-baked film is irradiated with radiation (e.g., visible light, ultraviolet light, far-ultraviolet light, X-rays, electron beams, gamma rays, or synchrotron radiation) through a photomask having a predetermined pattern (exposure step). Preferred radiation is ultraviolet to visible light having a wavelength of 250 to 450 nm. In one embodiment, the radiation is i-rays. In another embodiment, the radiation is ghi-rays.

[0121] If the binder resin (A) contains a protective resin (a2), a heat treatment (PEB) may be performed after the exposure process to promote the decomposition of acid-degradable groups. PEB can further increase the alkali solubility of the protective resin (a2) in the exposed area. The heating conditions vary depending on the type and proportion of each component, but PEB can usually be performed at 70 to 140°C, for example, by heating on a hot plate for 30 seconds to 20 minutes or in an oven for 1 to 60 minutes. In one embodiment, PEB after the exposure process can be omitted.

[0122] After the exposure or PEB process, the film is developed by contacting it with a developer solution to remove unwanted parts and form a pattern on the film (development process). As a developer, aqueous solutions of alkaline compounds such as inorganic alkali compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-propylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline; and cyclic amines such as pyrrole, piperidine, 1,8-diazabicyclo[5.4.0]-7-undecene and 1,5-diazabicyclo[4.3.0]-5-nonane can be used. An aqueous solution obtained by adding an appropriate amount of water-soluble organic solvent such as methanol or ethanol, or a surfactant, to an alkaline aqueous solution can also be used as a developer. The development time is usually 30 to 180 seconds. The development method can be any of the following: liquid immersion method, shower method, or dipping method. After development, the film can be rinsed with running water for 30 to 90 seconds to remove unwanted parts, and then air-dried with compressed air or compressed nitrogen to form a pattern.

[0123] Subsequently, the patterned coating can be heated using a heating device such as a hot plate or oven at, for example, 100 to 350°C for 20 to 200 minutes to obtain a cured coating (post-bake, heat treatment step). During the heat treatment, the temperature may be maintained at a constant level, continuously increased, or increased in stages. The heat treatment is preferably carried out under a nitrogen atmosphere.

[0124] The optical density (OD value) of the cured film of the photosensitive resin composition is preferably 0.5 or higher per 1 μm of film thickness, more preferably 0.7 or higher, and even more preferably 1.0 or higher. If the OD value of the cured film is 0.5 or higher per 1 μm of film thickness, sufficient light-shielding properties can be obtained.

[0125] A method for manufacturing an organic EL element partition or organic EL element insulating film according to one embodiment includes: preparing a coating composition by dissolving or dispersing a photosensitive resin composition in a solvent; applying the coating composition to a substrate to form a film; removing the solvent contained in the film to dry the film; exposing the film by irradiating the dried film with radiation through a photomask; developing the exposed film by contacting it with a developer solution to form a pattern on the film; and heat-treating the patterned film at a temperature of 100°C to 350°C to form an organic EL element partition or insulating film. The above PEB can also be performed after exposure and before development.

[0126] One embodiment is an organic EL element partition containing a cured product of a photosensitive resin composition.

[0127] One embodiment is an organic EL element insulating film containing a cured product of a photosensitive resin composition.

[0128] One embodiment is an organic EL element comprising a cured product of a photosensitive resin composition. [Examples]

[0129] The present invention will be described in detail below based on examples and comparative examples, but the present invention is not limited to these examples.

[0130] (1) Raw materials The raw materials used in the examples and comparative examples were manufactured or obtained as follows.

[0131] The weight-average molecular weight and number-average molecular weight of each resin contained in binder resin (A) were calculated using a calibration curve created with polystyrene standard material under the following measurement conditions. Device name: Shodex(registered trademark) GPC-101 Column: Shodex(registered trademark) LF-804 Mobile phase: tetrahydrofuran Flow rate: 1.0mL / min Detector: Shodex(registered trademark) RI-71 Temperature: 40℃

[0132] [Production Example 1] Production of a copolymer (a1) (PCX-02e) of a polymerizable monomer having a phenolic hydroxyl group and other polymerizable monomers 29.0 g of 4-hydroxyphenyl methacrylate (PQMA, manufactured by Showa Denko K.K.) and 5.12 g of N-cyclohexylmaleimide (manufactured by Nippon Shokubai Co., Ltd.) were completely dissolved in 96.5 g of 1-methoxy-2-propyl acetate (manufactured by Daicel Corporation) as a solvent. 3.41 g of V-601 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a polymerization initiator to 13.7 g of 1-methoxy-2-propyl acetate (manufactured by Daicel Corporation). The two resulting solutions were simultaneously added dropwise over 2 hours to 40.0 g of 1-methoxy-2-propyl acetate (manufactured by Daicel Corporation), heated to 85°C under a nitrogen atmosphere, in a 300 mL three-necked flask, and then reacted at 85°C for 3 hours. The reaction solution, cooled to room temperature, was added dropwise to 815 g of toluene to precipitate the copolymer. The precipitated copolymer was recovered by filtration and vacuum-dried at 90°C for 4 hours, yielding 32.4 g of a white powder. The number-average molecular weight of the obtained PCX-02e was 3100, and the weight-average molecular weight was 6600.

[0133] [Manufacturing Example 2] Production of protective resin (a2) (PCX-02e-THF55) in which phenolic hydroxyl groups are protected by 2-tetrahydrofuranyl groups In a 100 mL three-necked flask, 10.0 g of a copolymer (a1) (PCX-02e) of a polymerizable monomer having a phenolic hydroxyl group and other polymerizable monomers, and 0.60 g of pyridinium salt of p-toluenesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) as an acid catalyst were dissolved in 50.0 g of tetrahydrofuran (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). The mixture was then cooled on ice under a nitrogen gas atmosphere, and 6.69 g of 2,3-dihydrofuran (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 1 hour. The mixture was then stirred at room temperature for 16 hours. After neutralizing the acid catalyst with saturated sodium bicarbonate aqueous solution, the aqueous layer was removed. The organic layer was then washed twice with water. The tetrahydrofuran was then removed by distillation. The obtained solid was dissolved in 50.0 g of ethyl acetate and added dropwise to 200 g of toluene to precipitate the product. The precipitate was collected by filtration and vacuum-dried at 80°C for 4 hours to obtain 11.0 g of a white powder. The obtained powder was dissolved in propylene glycol monomethyl ether acetate to obtain a 20% by mass solids solution of protective resin (a2) (PCX-02e-THF55) in which phenolic hydroxyl groups were protected by 2-tetrahydrofuranyl groups. The obtained PCX-02e-THF55 had a number-average molecular weight of 3716, a weight-average molecular weight of 6806, a proportion of phenolic hydroxyl groups protected by acid-degradable groups of 55 mol%, and the number of structural units represented by formula (4) in which at least one phenolic hydroxyl group is protected by an acid-degradable group was 55% of the total number of structural units of PCX-02e-THF55. The percentage of phenolic hydroxyl groups protected by acid-degradable groups was calculated using a thermogravimetric differential thermal analyzer (TG / DTA6200, manufactured by Hitachi High-Tech Science Corporation). The temperature was raised from room temperature to 250°C under a nitrogen gas flow and a heating rate of 10°C / min, held for 10 minutes, and then further raised to 400°C under the same heating rate of 10°C / min. The weight loss rate (%) of PCX-02e-THF55 at 260°C was then calculated.

[0134] [Manufacturing Example 3] Manufacturing of a resin (a3) ​​(N695OH70) having epoxy groups and phenolic hydroxyl groups 75.2 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) and 42.8 g of EPICLON® N-695 (a cresol novolac type epoxy resin manufactured by DIC Corporation, epoxy equivalent 214), which has at least two epoxy groups in one molecule, were charged into a 300 mL three-necked flask and dissolved at 60°C under a nitrogen gas atmosphere. 20.1 g of 3,5-dihydroxybenzoic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a hydroxybenzoic acid compound (0.65 equivalents per epoxy equivalent) and 0.166 g (0.633 mmol) of triphenylphosphine (manufactured by Tokyo Chemical Industry Co., Ltd.) as a reaction catalyst were added, and the reaction was carried out at 110°C for 21 hours. The reaction solution was allowed to return to room temperature, diluted with γ-butyrolactone to a solid content of 20% by mass, and filtered to obtain a solution of 304.2 g of resin (a3) ​​(N695OH70) having epoxy groups and phenolic hydroxyl groups. The number-average molecular weight of the obtained reactant was 3000, the weight-average molecular weight was 7500, and the epoxy equivalent was 2200.

[0135] <Binder resin (A)> PCX-02e, PCX-02e-THF55, and N695OH70 were used as binder resins (A).

[0136] <Quinone diazide adduct (B)> The compounds shown in Table 1 were used as quinone diazide adducts (B).

[0137] [Table 1]

[0138] Table 2 shows the structural formula of the quinone diazide adduct (B). In the structural formula, R is a hydrogen atom or [ka] It represents.

[0139] [Table 2-1]

[0140] [Table 2-2]

[0141] <Black coloring agent (C)> As the black coloring agent (C), VALIFAST® BLACK 3820 (a black dye specified in the CI of Solvent Black 27, manufactured by Orient Chemical Industry Co., Ltd.) was used.

[0142] <Dissolution accelerator (D)> Phloroglucinol was used as a dissolution accelerator (D).

[0143] <Solvent (F)> A mixed solvent of γ-butyrolactone (GBL) and propylene glycol monomethyl ether acetate (PGMEA) (GBL:PGMEA = 40:60 (mass ratio)) was used as solvent (F).

[0144] (2) Evaluation method The evaluation methods used in the examples and comparative examples are as follows.

[0145] [sensitivity] A photosensitive resin composition was bar-coated onto a glass substrate (100mm x 100mm x 1mm) to a dry film thickness of 1.5μm, and pre-baked by heating on a hot plate at 100°C for 1 minute. The film was exposed using an exposure apparatus incorporating a high-pressure mercury lamp (product name Multi-Light ML-251A / B, manufactured by Ushio Inc.) via a quartz photomask (with a φ10μm aperture pattern). The exposure amount was measured using an ultraviolet integrated light meter (product name UIT-150, light receiving unit UVD-S365, manufactured by Ushio Inc.). After exposure, alkaline development was performed for 60 seconds using a 2.38 mass% tetramethylammonium hydroxide aqueous solution with a spin developer (AD-1200, manufactured by Takizawa Sangyo Co., Ltd.). The above procedure was repeated while changing the exposure amount to find the minimum irradiation dose (mJ / cm²) at which a pattern with a hole diameter of 10μm could be formed after development.2 The sensitivity was defined as ).

[0146] [OD value of cured coating] A photosensitive resin composition was spin-coated onto a glass substrate (100 mm x 100 mm x 1 mm) to a dry film thickness of approximately 1.5 μm. The substrate was heated on a hot plate at 120°C for 80 seconds to dry the solvent. The film was then cured at 250°C for 60 minutes under a nitrogen gas atmosphere to obtain a coating. The OD value of the cured film was measured using a transmission densitometer (BMT-1, manufactured by Sakata Inx Engineering Co., Ltd.), corrected for the OD value of the glass alone, and converted to an OD value per 1 μm of film thickness. The film thickness was measured using an optical film thickness analyzer (F20-NIR, manufactured by Filmetrics Co., Ltd.).

[0147] (3) Preparation and evaluation of photosensitive resin compositions [Examples 1-12 and Comparative Examples 1-3] Binder resin (A) was mixed and dissolved according to the composition shown in Table 3. The resulting solution was then mixed with the quinone diazide adduct (B), black colorant (C), dissolution accelerator (D), and GBL / PGMEA mixed solvent (F) as shown in Table 3. After visual confirmation that the components had dissolved, the mixture was filtered through a Millipore filter with a pore size of 0.22 μm to prepare a photosensitive resin composition with a solid content concentration of 12% by mass. The parts by mass of the compositions in Table 3 are solid content equivalents. The evaluation results of the photosensitive resin compositions of Examples 1-12 and Comparative Examples 1-3 are shown in Table 3.

[0148] [Table 3-1]

[0149] [Table 3-2]

[0150] When comparing Examples 1-11, in which the binder resin (A) contains the protective resin (a2) PCX-02e-THF55, with Comparative Examples 1 and 3, Examples 1-11 showed higher sensitivity (lower exposure). Similarly, when comparing Example 12, in which the binder resin (A) does not contain the protective resin (a2) PCX-02e-THF55, with Comparative Example 2, Example 12 also showed higher sensitivity (lower exposure). [Industrial applicability]

[0151] The photosensitive resin composition according to this disclosure can be suitably used in radiation lithography to form partitions or insulating films of organic EL elements. Organic EL elements equipped with partitions or insulating films formed from the photosensitive resin composition according to this disclosure can be suitably used as electronic components of display devices that exhibit good contrast.

Claims

1. (A) Binder resin and (B1) The first quinone diazide adduct, which is a quinone diazide adduct to the first phenol compound, (B2) The second quinone diazide adduct, which is a quinone diazide adduct to the second phenol compound, (C) Black coloring agent and A photosensitive resin composition comprising the first phenol compound and the second phenol compound, wherein the difference between the molecular weight of the first phenol compound and the molecular weight of the second phenol compound is 40 to 500, and the molecular weight of the first phenol compound is smaller than the molecular weight of the second phenol compound. The aforementioned binder resin is of formula (4) 【Chemistry 1】 (In formula (4), R9 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R10 is an acid-degradable group, r is an integer from 0 to 5, s is an integer from 0 to 5, and r+s is an integer from 1 to 5.) A photosensitive resin composition comprising a resin having a structural unit represented by formula (4), wherein s is an integer of 1 or more, and having at least one structural unit represented by formula (4).

2. The photosensitive resin composition according to claim 1, wherein the first phenol compound and the second phenol compound each have three or more phenolic hydroxyl groups.

3. The photosensitive resin composition according to claim 1 or 2, wherein the phenolic hydroxyl group equivalent of the first quinone diazide adduct is 100 to 1500, and the phenolic hydroxyl group equivalent of the second quinone diazide adduct is 180 to 800.

4. The photosensitive resin composition according to any one of claims 1 to 3, wherein the average number of phenolic hydroxyl groups of the first quinone diazide adduct is 0.1 to 3.0 per molecule, and the average number of phenolic hydroxyl groups of the second quinone diazide adduct is 0.5 to 5.0 per molecule.

5. The photosensitive resin composition according to any one of claims 1 to 4, wherein the first quinone diazide adduct is 1,2-naphthoquinone diazide-4-sulfonic acid ester or 1,2-naphthoquinone diazide-5-sulfonic acid ester of the first phenol compound.

6. The photosensitive resin composition according to any one of claims 1 to 5, wherein the second quinone diazide adduct is 1,2-naphthoquinone diazide-4-sulfonic acid ester or 1,2-naphthoquinone diazide-5-sulfonic acid ester of the second phenol compound.

7. The photosensitive resin composition according to any one of claims 1 to 6, wherein the molecular weight of the first phenol compound is 230 or more and less than 300, and the molecular weight of the second phenol compound is 300 or more and 600 or less.

8. A photosensitive resin composition according to any one of claims 1 to 7, comprising 5 to 70 parts by mass of the first quinone diazide adduct and 5 to 70 parts by mass of the second quinone diazide adduct, based on 100 parts by mass of the binder resin.

9. The photosensitive resin composition according to any one of claims 1 to 8, wherein the mass ratio of the first quinone diazide adduct to the second quinone diazide adduct (mass of the first quinone diazide adduct: mass of the second quinone diazide adduct) is 1:13 to 13:

1.

10. The binder resin comprises a copolymer of a polymerizable monomer having an alkali-soluble functional group and other polymerizable monomers, wherein the copolymer of the alkali-soluble functional group and other polymerizable monomers is of formula (1) 【Chemistry 2】 (In equation (1), R １ (where a is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a is an integer from 1 to 5.) A photosensitive resin composition according to any one of claims 1 to 9, having a structural unit represented by .

11. The binder resin comprises a resin having epoxy groups and phenolic hydroxyl groups, and the resin having epoxy groups and phenolic hydroxyl groups is a reaction product of a compound having at least two epoxy groups in one molecule and a hydroxybenzoic acid compound, the formula being (7) 【Transformation 3】 (In formula (7), b is an integer from 1 to 5, and * represents the binding site with the residue excluding the epoxy group involved in the reaction, in a compound having at least two epoxy groups in one molecule.) A photosensitive resin composition according to any one of claims 1 to 10, wherein the compound has the structure of [the specified structure].

12. The photosensitive resin composition according to claim 11, wherein the compound having at least two epoxy groups in one molecule is a novolac-type epoxy resin.

13. The photosensitive resin composition according to any one of claims 1 to 12, wherein the optical density (OD value) of the cured film of the photosensitive resin composition is 0.5 or more per 1 μm of film thickness.

14. The photosensitive resin composition according to any one of claims 1 to 13, wherein the black coloring agent is a dye defined by the color index (C.I.) of Solvent Black 27 to 47.

15. A photosensitive resin composition according to any one of claims 1 to 14, comprising 100 parts by mass of the binder resin and 10 to 150 parts by mass of the black coloring agent.

16. An organic EL element partition comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 15.

17. An insulating film for an organic EL element comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 15.

18. An organic EL element comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 15.

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