WO2022220080A1

WO2022220080A1 - Photosensitive resin composition and organic el element partition wall

Info

Publication number: WO2022220080A1
Application number: PCT/JP2022/014606
Authority: WO
Inventors: 良和新井
Original assignee: 昭和電工株式会社
Priority date: 2021-04-14
Filing date: 2022-03-25
Publication date: 2022-10-20
Also published as: TWI821974B; KR20230170903A; CN116940897A; TW202305507A; JPWO2022220080A1

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

Photosensitive resin composition and organic EL element partition

The present invention relates to a photosensitive resin composition, an organic EL element partition wall, 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 an organic EL element partition wall, an organic EL element insulating film, and an organic EL element using the same.

In a display device such as an organic EL display (OLED), in order to improve display characteristics, a partition material is used in the gap between the colored patterns in the display area or the edge of the display area peripheral portion. In the manufacture of an organic EL display device, partition walls are first formed, and organic pixels are formed between the partition walls in order to prevent organic substance pixels from coming into contact with each other. This partition is generally formed by photolithography using a photosensitive resin composition and has insulating properties. Specifically, a photosensitive resin composition is applied onto a substrate using a coating device, volatile components are removed by means of heating or the like, and then exposed through a mask. In the case of the positive type, the exposed portion is developed by removing it with a developing solution such as an alkaline aqueous solution, and the resulting pattern is heat-treated to form a partition wall (insulating film). Next, by an ink jet method or the like, an organic substance emitting three colors of red, green, and blue is deposited between the barrier ribs to form the pixels of the organic EL display device.

In this field, in recent years, due to the miniaturization of display devices and the diversification of content to be displayed, there is a demand for higher performance and higher definition of pixels. Attempts have been made to impart a light-shielding property to the partition wall material by using a coloring agent for the purpose of increasing the contrast in the display device and improving the visibility. However, when the partition wall material is provided with a light-shielding property, the sensitivity of the photosensitive resin composition tends to be low, and as a result, the exposure time becomes long, which may reduce productivity. Therefore, the photosensitive resin composition used for forming the partition wall material containing the colorant is required to have higher sensitivity.

Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2001-281440) discloses a positive radiation-sensitive resin composition containing an alkali-soluble resin and a quinonediazide compound as a radiation-sensitive resin composition exhibiting high light-shielding properties by heat treatment after exposure. describes a composition to which titanium black is added.

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

Patent Document 3 (Japanese Patent Application Laid-Open No. 2010-237310) describes a positive radiation-sensitive resin composition containing an alkali-soluble resin and a quinonediazide compound as a radiation-sensitive resin composition that exhibits light-shielding properties by heat treatment after exposure. Compositions with added thermal dyes are described.

Patent Document 4 (International Publication No. 2017/069172) discloses (A) a binder resin, (B) a quinonediazide compound, and (C) at least one black dye selected from solvent black color indexes 27 to 47. A positive-acting photosensitive resin composition containing a black dye is described.

Japanese Patent Application Laid-Open No. 2001-281440 JP-A-2002-116536 Japanese Patent Application Laid-Open No. 2010-237310 WO2017/069172

In the photosensitive resin composition used to form a colored partition wall material, it is necessary to use a considerable amount of a coloring agent in order to sufficiently enhance the light shielding properties of the cured film. When such a large amount of colorant is used, the radiation irradiated to the film of the photosensitive resin composition is absorbed by the colorant, so that the effective intensity of the radiation in the film is reduced, and the photosensitive resin composition is not sufficiently exposed, resulting in poor patternability.

In the formation of partition walls in organic EL elements, it is important from the viewpoint of productivity that the material forming the partition walls has high sensitivity. However, when a black photosensitive resin composition containing a colorant is used, exposure failure occurs under the exposure conditions normally used, so it is necessary, for example, to lengthen the exposure time, which reduces productivity. It was a factor that made Therefore, it is strongly desired to reduce the exposure amount of the photosensitive resin composition, reduce the energy cost, and increase the throughput.

An object of the present invention is to provide a highly sensitive photosensitive resin composition containing a black colorant that enables development and pattern formation even with a low exposure dose.

The present inventors prepared a photosensitive resin composition containing a binder resin, a quinonediazide adduct of a phenolic compound, and a black colorant as a system containing a plurality of quinonediazide adducts having different molecular weights of the phenolic compound constituting the quinonediazide adduct. As a result, it has been found that development and pattern formation are possible even with a low exposure amount, in spite of containing a black colorant.

That is, the present invention includes the following aspects.
[1]
(A) a binder resin;
(B1) a first quinonediazide adduct that is a quinonediazide adduct to a first phenol compound;
(B2) a second quinonediazide adduct that is a quinonediazide adduct to a second phenol compound;
(C) a photosensitive resin composition containing a black colorant, wherein the difference between the molecular weight of the first phenolic compound and the molecular weight of the second phenolic compound is 40 to 500, and A photosensitive resin composition having a molecular weight smaller than that of the second phenol compound.
[2]
The photosensitive resin composition according to [1], wherein each of the first phenolic compound and the second phenolic compound has three or more phenolic hydroxyl groups.
[3]
The photosensitivity according to either [1] or [2], wherein the first quinonediazide adduct has a phenolic hydroxyl equivalent of 100 to 1500, and the second quinonediazide adduct has a phenolic hydroxyl equivalent of 180 to 800. elastic resin composition.
[4]
The average number of phenolic hydroxyl groups per molecule of the first quinonediazide adduct is 0.1 to 3.0, and the average number of phenolic hydroxyl groups of the second quinonediazide adduct is 0.5 to 5.0 per molecule. 0, the photosensitive resin composition according to any one of [1] to [3].
[5]
[1] to [4], wherein the first quinonediazide adduct is 1,2-naphthoquinonediazide-4-sulfonate or 1,2-naphthoquinonediazide-5-sulfonate of the first phenol compound. The photosensitive resin composition according to any one of the above.
[6]
[1] to [5], wherein the second quinonediazide adduct is 1,2-naphthoquinonediazide-4-sulfonate or 1,2-naphthoquinonediazide-5-sulfonate of the second phenol compound. The photosensitive resin composition according to any one of the above.
[7]
The photosensitive resin composition according to any one of [1] to [6], wherein the first phenol compound has a molecular weight of 230 or more and less than 300, and the second phenol compound has a molecular weight of 300 or more and 600 or less.
[8]
Based on 100 parts by mass of the binder resin, 5 parts by mass to 70 parts by mass of the first quinonediazide adduct and 5 parts by mass to 70 parts by mass of the second quinonediazide adduct of [1] to [7] The photosensitive resin composition according to any one of the above.
[9]
The mass ratio of the first quinonediazide adduct to the second quinonediazide adduct (mass of the first quinonediazide adduct: mass of the second quinonediazide adduct) is 1:13 to 13:1 [1] to The photosensitive resin composition according to any one of [8].
[10]
The binder resin contains a polymerizable monomer having an alkali-soluble functional group and a copolymer of other polymerizable monomers, and the polymerizable monomer having an alkali-soluble functional group and the other polymerizable monomer. A copolymer of the formula (1)

(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.)
The photosensitive resin composition according to any one of [1] to [9], having a structural unit represented by
[11]
The binder resin contains a resin having an epoxy group and a phenolic hydroxyl group, and the resin having an epoxy group and a phenolic hydroxyl group reacts a compound having at least two epoxy groups in one molecule with a hydroxybenzoic acid compound. , and the formula (7)

(In the formula (7), b is an integer of 1 to 5, and * represents the bonding portion of the compound having at least two epoxy groups in one molecule with the residue excluding the epoxy group involved in the reaction. .)
The photosensitive resin composition according to any one of [1] to [10], which is a compound having a structure of
[12]
The photosensitive resin composition according to [11], wherein the compound having at least two epoxy groups in one molecule is a novolac epoxy resin.
[13]
The binder resin has the formula (4)

(In formula (4), R ⁹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ¹⁰ is an acid-decomposable group, r is an integer of 0 to 5, s is 0 to 5 is an integer of , where r + s is an integer of 1 to 5.)
The resin according to any one of [1] to [12], comprising a resin having at least one structural unit represented by formula (4), wherein s is an integer of 1 or more. A photosensitive resin composition.
[14]
The photosensitive resin composition according to any one of [1] to [13], wherein the cured film of the photosensitive resin composition has an optical density (OD value) of 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 colorant is a dye defined by a color index (C.I.) of Solvent Black 27 to 47.
[16]
The photosensitive resin composition according to any one of [1] to [15], containing 10 parts by mass to 150 parts by mass of the black colorant based on 100 parts by mass of the binder resin.
[17]
[1] An organic EL element partition comprising a cured product of the photosensitive resin composition according to any one of [1] to [16].
[18]
An organic EL element insulating film comprising a cured product of the photosensitive resin composition according to any one of [1] to [16].
[19]
An organic EL device comprising a cured product of the photosensitive resin composition according to any one of [1] to [16].

According to the present invention, it is possible to provide a highly sensitive photosensitive resin composition containing a black colorant that allows development and pattern formation even with a low exposure dose.

The present invention will be described in detail below.

In the present disclosure, "alkali-soluble" and "alkali aqueous solution-soluble" mean that the photosensitive resin composition or its components, or the coating or cured coating of the photosensitive resin composition is a 2.38% by mass aqueous tetramethylammonium hydroxide solution. means that it is soluble in The “alkali-soluble functional group” means a group that imparts such alkali solubility to the photosensitive resin composition or its components, or the coating or cured coating of the photosensitive resin composition. Alkali-soluble functional groups include, for example, phenolic hydroxyl groups, carboxy groups, sulfo groups, phosphoric acid groups, acid anhydride groups, and mercapto groups.

In the present disclosure, "acid-decomposable group" means a group that is decomposed (deprotected) by heating in the presence of an acid as necessary to generate an alkali-soluble functional group.

In the present disclosure, "radical polymerizable functional group" means an ethylenically unsaturated group, and "radical polymerizable compound" means a compound having one or more ethylenically unsaturated groups.

In the present disclosure, "structural unit" means an atomic group that constitutes 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 radically polymerizable compound used as a monomer, and in the case of a phenol novolac resin, one molecule of phenol (C ₆ H ₅ OH) and one means the following units formed from the condensation reaction of molecular formaldehyde (HCHO). Structural units with pendant groups (side groups) include structural units with pendant groups used to form cross-linking sites or groups derived from them, and structural units with free pendant groups that are not involved in the formation of cross-linking sites. are considered to be different from each other. Regarding a polymer having a branched molecular chain (branched chain), the structural unit containing the branch point (branching unit) and the structural unit contained in the linear molecular chain are considered different from each other.

In the present disclosure, "(meth)acrylic" means acrylic or methacrylic, "(meth)acrylate" means acrylate or methacrylate, and "(meth)acryloyl" means acryloyl or methacryloyl.

In the present disclosure, the number average molecular weight (Mn) and weight average molecular weight (Mw) of the resin, polymer or copolymer are measured at 40°C by gel permeation chromatography (GPC, gel permeation chromatography) using tetrahydrofuran as a mobile phase. Means the standard polystyrene conversion value measured.

In the present disclosure, "solid content" means (A) a binder resin, (B1) a first quinonediazide adduct, (B2) a second quinonediazide adduct, (C) a black colorant, and an optional dissolution accelerator (D). , and the optional component (E), excluding the solvent (F).

[Photosensitive resin composition]
The photosensitive resin composition of one embodiment comprises (A) a binder resin, (B1) a first quinonediazide adduct that is a quinonediazide adduct to a first phenol compound, and (B2) a second It contains a second quinonediazide adduct that is a quinonediazide adduct to a phenol compound, and (C) a black colorant.

<Binder resin (A)>
Although the binder resin (A) is not particularly limited, it preferably has an alkali-soluble functional group and is alkali-soluble. Examples of alkali-soluble functional groups include, but are not limited to, carboxy 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 be used.

Examples of the binder resin (A) include homopolymers or copolymers of polymerizable monomers having alkali-soluble functional groups, and resins having epoxy groups and phenolic hydroxyl groups. Other binder resins (A) include, for example, acrylic resins, polystyrene resins, epoxy resins, polyamide resins, phenol resins, polyimide resins, polyamic acid resins, polybenzoxazole resins, polybenzoxazole resin precursors, silicone resins, cyclic Olefin polymers, cardo resins, derivatives of these resins, and alkali-soluble functional groups attached to these resins. For example, phenol resin derivatives include polyalkenylphenol resins in which alkenyl groups are bonded to benzene rings, and polystyrene resin derivatives include hydroxypolystyrene resin derivatives in which phenolic hydroxyl groups and hydroxyalkyl groups or alkoxy groups are bonded to benzene rings. be done. These resins can be used alone or in combination of two or more.

The binder resin (A) may have a radically polymerizable functional group. In one embodiment, the binder resin (A) has a (meth)acryloyloxy group, allyl group or methallyl group as a radically polymerizable functional group.

Some or all of the alkali-soluble functional groups of the binder resin (A), such as phenolic hydroxyl groups, may be protected with acid-decomposable groups. The alkali solubility of the binder resin (A) protected with an acid-decomposable group is suppressed before exposure. The quinonediazide adducts (B1) and (B2) described later generate alkali-soluble carboxylic acid compounds when exposed to radiation such as visible light, ultraviolet light, γ-rays and electron beams. The produced carboxylic acid compound accelerates the decomposition of the acid-decomposable groups of the binder resin (A), regenerates the alkali-soluble functional groups, and increases 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 the acid-decomposable group) is increased, and the pattern resolution can be further enhanced.

(Copolymer (a1) of a polymerizable monomer having an alkali-soluble functional group and another polymerizable monomer)
In one embodiment, the binder resin (A) is a copolymer (a1) of a polymerizable monomer having an alkali-soluble functional group and another polymerizable monomer (in the present disclosure, simply "aqueous alkaline solution-soluble copolymer (a1)”). Alkali-soluble functional groups include, for example, a carboxy group, a phenolic hydroxyl group, a sulfo group, a phosphoric acid group, an acid anhydride group, and a mercapto group. Examples of the polymerizable functional group possessed by the polymerizable monomer include radically polymerizable functional groups such as CH ₂ ═CH—, CH ₂ ═C(CH ₃ )—, CH ₂ ═CHCO—, CH ₂ =C(CH ₃ )CO-, -OC-CH=CH-CO- and the like.

The aqueous alkaline solution-soluble copolymer (a1) can be produced, for example, by radically polymerizing a polymerizable monomer having an alkali-soluble functional group and other polymerizable monomers. After synthesizing a copolymer by radical polymerization, a derivative obtained by adding an alkali-soluble functional group to the copolymer may be used. Examples of the polymerizable monomer 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 maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid, cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid, 3-maleimidopropionate acid, 4-maleimidobutyric acid, 6-maleimidohexanoic acid and other polymerizable monomers having a carboxy group; 4-hydroxystyrene, 4-hydroxyphenyl (meth)acrylate, 3,5-dimethyl-4-hydroxybenzylacrylamide, Polymerizable monomers having a phenolic hydroxyl group such as 4-hydroxyphenylacrylamide and 4-hydroxyphenylmaleimide; (meth)allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, styrenesulfonic acid and the like Polymerizable monomers having a sulfo group; Polymerizable monomers having a phosphoric acid group such as mono (2-(meth)acryloyloxyethyl) phosphate; and maleic anhydride, itaconic anhydride, citraconic anhydride, etc. and a polymerizable monomer having an acid anhydride group of Other polymerizable monomers include, for example, styrene derivatives such as styrene, vinyl toluene, α-methylstyrene, p-methylstyrene and p-ethylstyrene; acrylamide; acrylonitrile; vinyl alcohols such as vinyl-n-butyl ether. Ether compounds; 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, phenyl (meth)acrylate, 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, 2,2,3,3-tetrafluoropropyl (meth) ) (meth)acrylic acid esters such as acrylates; and N-substituted maleimides such as phenylmaleimide and cyclohexylmaleimide. From the viewpoint of heat resistance and the like, the copolymer (a1) soluble in an alkaline aqueous solution has one or more types of rings such as an alicyclic structure, an aromatic structure, a polycyclic structure, an inorganic cyclic structure, and a heterocyclic structure. It is preferred to have the formula structure.

The polymerizable monomer having an alkali-soluble functional group preferably has one or more cyclic structures. A polymerizable monomer having an alkali-soluble functional group preferably has a phenolic hydroxyl group. The polymerizable monomer having an alkali-soluble functional group is a (meth)acrylic compound having CH ₂ =CHCO- or CH ₂ =C(CH ₃ )CO- as a radically polymerizable functional group, and -OC-CH= It is preferably at least one selected from the group consisting of maleimide compounds having CH--CO--. As a polymerizable monomer having an alkali-soluble functional group, the formula (1) after polymerization

Forming a structural unit represented by is more preferable. 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, more preferably 1; 4-Hydroxyphenyl methacrylate is particularly preferred as such a polymerizable monomer having an alkali-soluble functional group.

As other polymerizable monomers, formula (2) after polymerization

A polymerizable monomer that forms a structural unit represented by is preferred. In formula (2), R ² and R ³ are each 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 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 hydroxy group, or a A phenyl group substituted with at least one selected from the group consisting of an alkyl group and an alkoxy group having 1 to 6 carbon atoms. R ² and R ³ are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom. R ⁴ is at least one selected from the group consisting of a cyclic alkyl group having 3 to 12 carbon atoms, a phenyl group, or a hydroxy group, an alkyl group having 1 to 6 carbon atoms and an alkoxy group having 1 to 6 carbon atoms; A phenyl group substituted with a species is preferable, and a cyclic alkyl group having 3 to 12 carbon atoms or a phenyl group is more preferable. Phenylmaleimide and N-cyclohexylmaleimide are particularly preferred as such other polymerizable monomers.

The alkaline aqueous solution-soluble copolymer (a1) has the formula (1)

(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.)
It is preferable to have a structural unit represented by

The alkaline aqueous solution-soluble copolymer (a1) has the formula (2)

(In Formula (2), R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a fully or partially fluorinated fluoroalkyl group having 1 to 3 carbon atoms. , or a halogen atom, and R ⁴ 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 hydroxy group, or a 1 to 6 carbon atom is a phenyl group substituted with at least one selected from the group consisting of an alkyl group and an alkoxy group having 1 to 6 carbon atoms.)
It is preferable to have a structural unit represented by

It is particularly preferable to use 4-hydroxyphenyl methacrylate as the polymerizable monomer having an alkali-soluble functional group, and phenylmaleimide or N-cyclohexylmaleimide as the other polymerizable monomer. By using a resin obtained by radically polymerizing these polymerizable monomers, it is possible to improve shape retention and developability and reduce outgassing.

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

A RAFT (Reversible Addition Fragmentation Transfer) agent may be used in combination with the polymerization initiator. Thiocarbonylthio compounds such as, but not limited to, dithioesters, dithiocarbamates, trithiocarbonates, and xanthates can be used as RAFT agents. The RAFT agent can be used in the range of 0.005 to 20 parts by weight, preferably in the range of 0.01 to 10 parts by weight, per 100 parts by weight of the total polymerizable monomers.

The weight average molecular weight (Mw) of the alkaline 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 from 1,000 to 30,000, preferably from 1,500 to 25,000, more preferably from 2,000 to 20,000. The polydispersity (Mw/Mn) can be from 1.0 to 3.5, preferably from 1.1 to 3.0, more preferably from 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 having excellent alkali solubility and developability can be obtained.

In one embodiment, the photosensitive resin composition contains 1% by mass to 50% by mass, preferably 2% by mass to 40% by mass of the copolymer (a1) soluble in an alkaline aqueous solution, based on the solid content of 100% by mass. More preferably, it contains 5% by mass to 30% by mass. When the content of the aqueous alkaline solution-soluble copolymer (a1) is 1% by mass or more based on the solid content of 100% by mass, it is possible to promote the dissolution of the exposed area and achieve high sensitivity. can ensure the stability and durability of the coating. When the content of the alkaline aqueous solution-soluble copolymer (a1) is 50% by mass or less based on 100% by mass of solid content, the solubility of the unexposed areas can be kept low and a high residual film rate can be maintained.

(Protective resin (a2))
The binder resin (A) may contain a protective resin (a2) in which at least a part of the alkali-soluble functional groups are protected with an acid-decomposable group, using the above aqueous alkaline solution-soluble copolymer (a1) as a base resin. . The protective resin (a2) has a large change in alkali solubility before and after exposure (before and after decomposition of the acid-decomposable group), and as a result, the pattern resolution can be further improved. The acid generated during exposure catalytically promotes the decomposition (deprotection) of the acid-decomposable group to regenerate the phenolic hydroxyl group. After exposure, post exposure bake (PEB) may be performed as necessary. This promotes alkali dissolution of the protective resin (a2) in the exposed areas during development. The protective resin (a2) can be used alone or in combination of two or more. For example, the protective resin (a2) may be a combination of two or more resins differing in polymer structural units, acid-decomposable groups, protection ratios of alkali-soluble functional groups, or combinations thereof.

The alkali-soluble functional group in the protective resin (a2) is preferably a phenolic hydroxyl group. By protecting part of the phenolic hydroxyl groups with acid-decomposable groups, the alkali solubility of the protective resin (a2) before exposure is suppressed. The base resin of the protective resin (a2) preferably has a phenolic hydroxyl group on the benzene ring pendant to the polymer main chain. In the base resin of the protective resin (a2) having this structure, a benzene ring having a phenolic hydroxyl group constitutes the polymer main chain, and compared with a novolak resin having an equivalent hydroxyl value, the alkali compound in the developer is Easy access to phenolic hydroxyl groups and high alkali solubility.

(Protection of phenolic hydroxyl group by acid-decomposable group)
In an embodiment in which the alkali-soluble functional group of the protective resin (a2) is a phenolic hydroxyl group, the protective resin (a2) is prepared by using the above aqueous alkali solution-soluble copolymer (a1) having a phenolic hydroxyl group as a base resin, and the phenol can be obtained by protecting a part of the functional hydroxyl groups with an acid-decomposable group. The protective resin (a2) having a phenolic hydroxyl group protected with an acid-decomposable group has a partial structure of Ar—O—R ⁵ , Ar represents an aromatic ring derived from phenol, and R ⁵ is an acid-decomposable group. represents

The acid-decomposable group is a group that is decomposed (deprotected) by heating in the presence of an acid, if necessary, to generate an alkali-soluble functional group. Specifically, for example, tert-butyl group, 1,1-dimethyl-propyl group, 1-methylcyclopentyl group, 1-ethylcyclopentyl group, 1-methylcyclohexyl group, 1-ethylcyclohexyl group, 1-methyladamantyl group , 1-ethyladamantyl group, tert-butoxycarbonyl group, group having a tertiary alkyl group such as 1,1-dimethyl-propoxycarbonyl group; trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, triisopropylsilyl group , a silyl group such as a t-butyldiphenylsilyl group; and formula (3)
—CR ⁶ R ⁷ —OR ⁸ (3)
(In formula (3), R ⁶ and R ⁷ are each 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 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 a carbon atom an alkenyl group having a number of 2 to 12, and one of R ⁶ or R ⁷ and R ⁸ may combine to form a ring structure having 3 to 10 ring members, and R ⁶ , R ⁷ and R ⁸ are optionally 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 ketal structure together with an oxygen atom derived from a phenolic hydroxyl group. These acid-decomposable groups can be used alone or in combination of two or more.

The acid-decomposable group is preferably a group represented by formula (3), since a highly sensitive photosensitive resin composition can be obtained even with a low exposure dose. R ⁶ and R ⁷ are each 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 is fluorine, chlorine, bromine and optionally substituted with a halogen atom selected from the group consisting of iodine, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, or having 3 to 12 carbon atoms A cyclic alkyl group is more preferred. Examples of such acid-decomposable groups include 1-alkoxyalkyl groups. 1-alkoxyalkyl groups include, for example, 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; - n-propoxyethyl groups are preferred. As the acid-decomposable group, a group represented by formula (3) in which one of R ⁶ or R ⁷ and R ⁸ are bonded to form a ring structure having 3 to 10 ring members is also preferably used. can do. At this time, ^R6 or ^R7 that does not participate in the formation of the ring structure is preferably a hydrogen atom. Examples of such acid-decomposable groups include a 2-tetrahydrofuranyl group and a 2-tetrahydropyranyl group, with a 2-tetrahydrofuranyl group being preferred.

The protective reaction of phenolic hydroxyl groups can be carried out under known conditions using a general protective agent. For example, the protective resin (a2) can be obtained by reacting the base resin and the protective agent in the presence of an acid or base at a reaction temperature of -20 to 50°C in the presence of no solvent or a solvent such as toluene or hexane. can.

As a protective agent, a known protective agent capable of protecting phenolic hydroxyl groups can be used. Examples of protective agents that can be used include isobutene when the acid-decomposable group is a tert-butyl group and di-tert-butyl dicarbonate when the acid-decomposable group is a tert-butoxycarbonyl group. When the acid-decomposable group is a silyl group such as trimethylsilyl group and triethylsilyl group, silicon-containing chlorides such as trimethylsilyl chloride and triethylsilyl chloride, or silicon-containing triflate compounds such as trimethylsilyl triflate and triethylsilyl triflate can be used. . Chloromethyl methyl ether when the acid-decomposable group is a methoxymethyl group, ethyl vinyl ether when it is a 1-ethoxyethyl group, n-propyl vinyl ether when it is a 1-n-propoxyethyl group, and 2-tetrahydrofuranyl group when it is a 2-tetrahydrofuranyl group. In the case of 2,3-dihydrofuran and 2-tetrahydropyranyl groups, 3,4-dihydro-2H-pyran and the like can be used.

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 the base include inorganic hydroxides such as sodium hydroxide and potassium hydroxide; inorganic carbonates such as sodium carbonate, sodium hydrogen carbonate, potassium carbonate and cesium carbonate; metal hydrides such as sodium hydride; Amine compounds such as N,N-dimethyl-4-aminopyridine, imidazole, triethylamine and diisopropylethylamine are included.

In another embodiment, after protecting the phenolic hydroxyl group of the polymerizable monomer having a phenolic hydroxyl group with an acid-decomposable group, the polymerizable monomer having a phenolic hydroxyl group protected with an acid-decomposable group and the necessary The protective resin (a2) can also be obtained by polymerizing or copolymerizing other polymerizable monomers depending on the conditions. The phenolic hydroxyl group of the polymerizable monomer having a phenolic hydroxyl group can be protected by the same method as the protection of the phenolic hydroxyl group of the base resin.

The protective resin (a2) has the formula (4)

(In formula (4), R ⁹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ¹⁰ is an acid-decomposable group, r is an integer of 0 to 5, s is 0 to 5 where r + s is an integer of 1 to 5.) and has at least one structural unit represented by formula (4), wherein s is an integer of 1 or more is preferred. The acid-decomposable group for R ¹⁰ is preferably a group represented by formula (3) above.

The protective resin (a2) has the formula (2)

(In Formula (2), R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a fully or partially fluorinated fluoroalkyl group having 1 to 3 carbon atoms. , or a halogen atom, and R ⁴ 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 hydroxy group, or a 1 to 6 carbon atom is a phenyl group substituted with at least one selected from the group consisting of an alkyl group and an alkoxy group having 1 to 6 carbon atoms.). R ² and R ³ are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom. R ⁴ is at least one selected from the group consisting of a cyclic alkyl group having 3 to 12 carbon atoms, a phenyl group, or a hydroxy group, an alkyl group having 1 to 6 carbon atoms and an alkoxy group having 1 to 6 carbon atoms; A phenyl group substituted with a species is preferable, and a cyclic alkyl group having 3 to 12 carbon atoms or a phenyl group is more preferable.

In one embodiment, a structural unit represented by formula (4) and s is an integer of 1 or more, i.e., represented by formula (4) in which at least one phenolic hydroxyl group is protected with an acid-decomposable group The number of structural units is 5% to 95%, preferably 15% to 70%, more preferably 25% to 60% of the total number of structural units in the protective resin (a2). By setting the ratio of the structural unit to 5% or more, a chemical amplification function can be imparted to the photosensitive resin composition to realize high sensitivity. By setting the ratio of the structural unit to 95% or less, the residual amount of unreacted acid-decomposable groups can be reduced, the solubility of the exposed area can be improved, and high sensitivity can be realized.

In one embodiment, the photosensitive resin composition contains 5% by mass to 50% by mass of the protective resin (a2), preferably 10% by mass to 40% by mass, more preferably 15% by mass, based on the solid content of 100% by mass. % to 30% by mass. When the content of the protective resin (a2) is 5% by mass or more based on the solid content of 100% by mass, the dissolution of the exposed area can be promoted and the solubility of the unexposed area and the exposed area can be differentiated. Therefore, high sensitivity can be achieved, and the stability and durability of the film after thermosetting can be ensured. When the content of the protective resin (a2) is 50% by mass or less based on 100% by mass of the solid content, the solubility of the unexposed areas can be kept low and a high residual film rate can be maintained.

(Resin (a3) having an epoxy group and a phenolic hydroxyl group)
The binder resin (A) may contain a resin (a3) having an epoxy group and a phenolic hydroxyl group. The resin (a3) having an epoxy group and a phenolic hydroxyl group is an alkaline aqueous solution-soluble resin. The resin (a3) having an epoxy group and a phenolic hydroxyl group may have an alkali-soluble functional group other than the phenolic hydroxyl group. Phenolic hydroxyl groups and other alkali-soluble functional groups may be protected with acid-decomposable groups. The resin (a3) having an epoxy group and a phenolic hydroxyl group is, for example, a part of the epoxy groups of a compound having at least two epoxy groups in one molecule (hereinafter sometimes referred to as an "epoxy compound"). and a carboxy group of a hydroxybenzoic acid compound. The epoxy group of the resin (a3) having an epoxy group and a phenolic hydroxyl group forms crosslinks by reaction with the phenolic hydroxyl group during heat treatment (post-baking) after development, thereby improving the chemical resistance, heat resistance, etc. of the film. can be improved. Since the phenolic hydroxyl group contributes to the solubility in an alkaline aqueous solution during development, the resin (a3) having an epoxy group and a phenolic hydroxyl group is sufficiently decomposed (deprotected) when exposed to light at a low exposure dose. ) also functions as a dissolution accelerator for the binder resin (A) that has not been treated, thereby making it possible to increase the sensitivity of the photosensitive resin composition.

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

Compounds having at least two epoxy groups in one molecule include, for example, novolac epoxy resins such as phenol novolak epoxy resins and cresol novolac epoxy resins, bisphenol epoxy resins, biphenol epoxy resins, and naphthalene skeleton-containing epoxy resins. Mention may be made of resins, cycloaliphatic epoxy resins, and heterocyclic epoxy resins. These epoxy compounds may have two or more epoxy groups in one molecule, and may be used alone or in combination of two or more. Since these compounds are thermosetting, it is common knowledge for those skilled in the art that their structures cannot be uniquely described due to differences in the presence or absence of epoxy groups, types of functional groups, degrees of polymerization, and the like. An example of the structure of the novolak type epoxy resin is shown in formula (6). In formula (6), for example, R ¹⁴ is a hydrogen atom, an alkyl group having 1-5 carbon atoms, an alkoxy group having 1-2 carbon atoms or a hydroxyl group, and m is an integer of 1-50.

Examples of phenolic novolak-type epoxy resins include EPICLON (registered trademark) N-770 (manufactured by DIC Corporation) and JER (registered trademark)-152 (manufactured by Mitsubishi Chemical Corporation). Examples of cresol novolac epoxy resins include EPICLON (registered trademark) N-695 (manufactured by DIC Corporation) and EOCN (registered trademark)-102S (manufactured by Nippon Kayaku Co., Ltd.). Examples of bisphenol-type epoxy resins include bisphenol A such as jER (registered trademark) 828, jER (registered trademark) 1001 (manufactured by Mitsubishi Chemical Corporation), YD-128 (trade name, manufactured by Nippon Steel Chemical & Materials Co., Ltd.). type epoxy resins, and bisphenol F type epoxy resins such as JER (registered trademark) 806 (manufactured by Mitsubishi Chemical Corporation) and YDF-170 (trade name, manufactured by Nippon Steel Chemical & Materials Co., Ltd.). Biphenol-type epoxy resins include, for example, 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). Alicyclic epoxy resins include, for example, EHPE (registered trademark)-3150 (manufactured by Daicel Chemical Industries, Ltd.). Heterocyclic epoxy resins include, for example, TEPIC®, TEPIC-L, TEPIC-H, and TEPIC-S (manufactured by Nissan Chemical Industries, Ltd.).

The compound having at least two epoxy groups in one molecule is preferably a novolak type epoxy resin, more preferably at least one selected from the group consisting of phenol novolak type epoxy resins and cresol novolak type epoxy resins. preferable. A photosensitive resin composition containing a resin (a3) having an epoxy group derived from a novolak-type epoxy resin and a phenolic hydroxyl group has excellent pattern formability, is easy to adjust alkali solubility, and has little outgassing.

A hydroxybenzoic acid compound is a compound in which at least one of the 2-6 positions of benzoic acid is substituted with a hydroxyl group, and examples thereof include salicylic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, and 2,4-dihydroxybenzoic acid. 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- Examples include nitrobenzoic acid and 4-hydroxy-3-nitrobenzoic acid, and dihydroxybenzoic acid compounds are preferred from the viewpoint of enhancing alkali developability. A hydroxybenzoic acid compound can be used individually or in combination of 2 or more types.

In one embodiment, the resin (a3) having an epoxy group and a phenolic hydroxyl group is a reaction product of a compound having at least two epoxy groups in one molecule and a hydroxybenzoic acid compound, represented by formula (7)

has the structure In formula (7), b is an integer of 1 to 5, and * represents a bonding portion of a compound having at least two epoxy groups in one molecule with a residue other than the epoxy group involved in the reaction.

In the method of obtaining a resin (a3) having an epoxy group and a phenolic hydroxyl group from an epoxy compound and a hydroxybenzoic acid compound, 0.2 to 0.95 equivalents of the hydroxybenzoic acid compound are used with respect to 1 equivalent of the epoxy group of the epoxy compound. It can be used, preferably 0.3 to 0.9 equivalents, more preferably 0.4 to 0.8 equivalents. If the amount of the hydroxybenzoic acid compound is 0.2 equivalents or more, sufficient alkali solubility can be obtained, and if the amount is 0.95 equivalents or less, an increase in molecular weight due to side reactions can be suppressed.

A catalyst may be used to promote the reaction between the epoxy compound and the hydroxybenzoic acid compound. The amount of the catalyst used can be 0.1 to 10 parts by mass based on 100 parts by mass of the reaction raw material mixture comprising the epoxy compound and the hydroxybenzoic acid compound. The reaction temperature can be 60-150° C., and the reaction time can be 3-30 hours. Catalysts used in this reaction include, for example, triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, chromium octanoate, and zirconium octanoate.

The number average molecular weight (Mn) of the resin (a3) having an epoxy group and a phenolic hydroxyl group is preferably 500-8000, more preferably 800-6000, even more preferably 1000-5000. If the number-average molecular weight is 500 or more, the alkali solubility is appropriate, so it is good as a resin for a photosensitive material.

In one embodiment, the epoxy equivalent of the resin (a3) having an epoxy group and a phenolic hydroxyl group is 300-7000, preferably 400-6000, more preferably 500-5000. If the epoxy equivalent of the resin (a3) having an epoxy group and a phenolic hydroxyl group is 300 or more, sufficient alkali solubility can be imparted to the resin (a3) having an epoxy group and a phenolic hydroxyl group. If the epoxy equivalent of the resin (a3) having an epoxy group and a phenolic hydroxyl group is 7000 or less, the strength of the cured film can be increased. Epoxy equivalent is determined by JIS K 7236:2009.

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

In one embodiment, the photosensitive resin composition contains 5% by mass to 50% by mass, preferably 10% by mass to 40% by mass of the resin (a3) having an epoxy group and a phenolic hydroxyl group, based on the solid content of 100% by mass. %, more preferably 15% to 30% by mass. When the content of the resin (a3) having an epoxy group and a phenolic hydroxyl group is 5% 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. It is possible to ensure the stability and durability of the film after thermosetting. When the content of the resin (a3) having an epoxy group and a phenolic hydroxyl group is 50% by mass or less based on the solid content of 100% by mass, the solubility of the unexposed area is kept low and the residual film rate is kept high. can be done.

<First quinonediazide adduct (B1) and second quinonediazide adduct (B2)>
The photosensitive resin composition contains, as radiation-sensitive compounds, at least two quinonediazide adducts of phenol compounds, i.e., a first quinonediazide adduct (B1) which is a quinonediazide adduct to the first phenol compound, and a first quinonediazide adduct. A second quinonediazide adduct (B2) which is a quinonediazide adduct to a second phenol compound other than (B1) is also included. In the present disclosure, the first quinonediazide adduct (B1) and the second quinonediazide adduct (B2) are also collectively referred to as quinonediazide adduct (B). Similarly, in this disclosure, the first phenolic compound and the second phenolic compound are collectively referred to as phenolic compounds. The quinonediazide adduct (B) is, for example, a quinonediazide adduct (B) having a skeleton of a trivalent phenol compound represented by formula (8),

It means the following compounds in which at least one of the three phenolic hydroxyl groups of the phenol compound is substituted with a group having a quinonediazide structure, for example, a naphthoquinonediazide sulfonate group shown below. Substitution with a naphthoquinonediazide sulfonate group can be carried out by esterifying (sulfonating) the phenolic hydroxyl group of the phenol compound with a quinonediazide sulfonic acid halide.

In the above structural formula, each R is independently a hydrogen atom,

or

represents

When the quinonediazide adduct (B) is irradiated with ultraviolet light or the like, it undergoes the reaction shown in Reaction Formula 2 below to generate a carboxy group. The formation of carboxyl groups makes the exposed portion (coating) soluble in an alkaline aqueous solution, resulting in alkaline developability in that portion.

The present inventors used a first quinonediazide adduct (B1), which is a quinonediazide adduct to a first phenol compound, and a second quinonediazide adduct (B2), which is a quinonediazide adduct to a second phenol compound, as radiation-sensitive compounds. , The difference in molecular weight between the first phenolic compound and the second phenolic compound is 40 to 500, preferably 42 to 400, more preferably 45 to 350, so that the photosensitive resin composition can be produced while maintaining pattern formability. It was found that the sensitivity can be enhanced. Here, the molecular weight of the first phenol compound constituting the first quinonediazide adduct (B1) is smaller than the molecular weight of the second phenol compound constituting the second quinonediazide adduct (B2). Without being bound by any theory, it is believed that a quinonediazide adduct to a lower molecular weight first phenolic compound (first quinonediazide adduct (B1)) is a quinonediazide adduct to a higher molecular weight second phenolic compound ( The solubility of the exposed area is improved as compared with the second quinonediazide adduct (B2)). The second quinonediazide adduct (B2) suppresses excessive dissolution of the unexposed areas during development, while producing and dissolving a carboxylic acid compound in the exposed areas in the same manner as the first quinonediazide adduct (B1). Therefore, by using the first quinonediazide adduct (B1) and the second quinonediazide adduct (B2) together, the sensitivity of the photosensitive resin composition can be increased while maintaining the pattern formability. In the present invention, as means for adjusting the sensitivity of the photosensitive resin composition, not only the type and composition of the binder resin and additives such as dissolution accelerators, but also the quinonediazide adduct (B), which is a radiation-sensitive compound, can be used. In terms of presenting, it has a technical significance of increasing the degree of freedom in designing the photosensitive resin composition.

Examples of phenolic compounds include Bis-Z, BisP-EZ, TekP-4HBPA, TrisP-HAP, TrisP-PA, TrisP-SA, TrisOCR-PA, BisOCHP-Z, BisP-MZ, BisP-PZ, and BisP-IPZ. , BisOCP-IPZ, BisP-CP, BisRS-2P, BisRS-3P, BisP-OCHP, methylene tris-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-MTrisPC, TriML-P, TriML-35XL, TML-BP, TML- HQ, TML-pp-BPF, TML-BPA, TMOM-BP, HML-TPPHBA, HML-TPHAP (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, methylene bisphenol, and BisP-AP (trade name, manufactured by Honshu Chemical Industry Co., Ltd.), but are not limited thereto. The first phenolic compound and the second phenolic compound can be selected in combination so as to have a predetermined molecular weight difference.

The first phenol compound and the second phenol compound each preferably have three or more phenolic hydroxyl groups. The first quinonediazide adduct (B1) and the second quinonediazide adduct (B2) obtained from a phenol compound having three or more phenolic hydroxyl groups have a high level of balance between photosensitivity and solubility. The sensitivity of the photosensitive resin composition can be improved.

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, still more preferably 230 or more and 260 or less. When the molecular weight of the first phenol compound is 230 or more, excessive dissolution of the unexposed area can be suppressed, and a difference in solubility can be made between the unexposed area and the exposed area. When the molecular weight of the first phenol compound is less than 300, the solubility of the exposed area can be maximized.

The molecular weight of the second phenol compound is preferably 300 or more and 600 or less, more preferably 300 or more and 590 or less, and still more preferably 300 or more and 580 or less. When the molecular weight of the second phenol compound is 300 or more, excessive dissolution of the unexposed area can be suppressed, and a difference in solubility can be made between the unexposed area and the exposed area. When the molecular weight of the second phenol compound is 600 or less, it is possible to suppress residue in the exposed area and obtain good pattern formability.

Suitable phenolic compounds include, for example, those having the following structural formulas.

The quinonediazide adduct (B) can be obtained, for example, by subjecting a phenolic hydroxyl group of a phenol compound to an esterification reaction with a compound represented by formula (9) or (10).

In formulas (9) and (10), R ^a to R ^d each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and X is a halogen atom. or OH.

R ^a to R ^d are each independently preferably 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 more preferably a hydrogen atom. X is preferably a chlorine atom. Examples of the compounds represented by formulas (9) and (10) include 1,2-naphthoquinonediazide-4-sulfonyl chloride and 1,2-naphthoquinonediazide-5-sulfonyl chloride. , 2-naphthoquinonediazide-5-sulfonic acid chloride is preferred.

In one embodiment, in the quinonediazide adduct (B), the phenolic hydroxyl group of the phenol compound is substituted with a group having a quinonediazide structure represented by formula (11) or formula (12).

In formulas (11) and (12), R ^a to R ^d each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and * is a phenol compound. shows the bond with the oxygen atom of the phenolic hydroxyl group. R ^a to R ^d are each independently preferably 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 more preferably a hydrogen atom.

The first quinonediazide adduct (B1) and the second quinonediazide adduct (B2) are each independently a 1,2-naphthoquinonediazide-4-sulfonic acid ester or 1,2-naphthoquinonediazide-5-sulfonic acid of a phenol compound. It preferably contains an ester, more preferably 1,2-naphthoquinonediazide-4-sulfonate or 1,2-naphthoquinonediazide-5-sulfonate of a phenol compound. The first quinonediazide adduct (B1) and the second quinonediazide adduct (B2) each independently contain a 1,2-naphthoquinonediazide-4-sulfonate ester bond and a 1,2-naphthoquinonediazide-5- It may have both sulfonate ester bonds. In one embodiment, the quinonediazide adduct (B) is 1,2-naphthoquinonediazide-4-sulfonate. In another embodiment, the quinonediazide adduct (B) is 1,2-naphthoquinonediazide-5-sulfonate.

The degree of substitution in the quinonediazide adduct (B) (percentage of the phenolic hydroxyl group of the phenolic compound substituted with a group having a quinonediazide structure based on all molecules of the quinonediazide adduct (B)) is preferably 20 mol% or more. , more preferably 30 mol % or more, still more preferably 40 mol % or more. By setting the degree of substitution to 20 mol % or more, the difference in solubility between the unexposed area and the exposed area can be increased. The degree of substitution may be 100 mol % or less, 95 mol % or less, or 93 mol % or less.

The degree of substitution in the first quinonediazide adduct (B1) (percentage of the phenolic hydroxyl group of the first phenol compound substituted with a group having a quinonediazide structure based on all molecules of the quinonediazide adduct (B1)) is preferably It is 20 mol % or more, more preferably 30 mol % or more, still more preferably 40 mol % or more. By setting the degree of substitution to 20 mol % or more, the difference in solubility between the unexposed area and the exposed area can be increased. The degree of substitution may be 100 mol % or less, 95 mol % or less, or 93 mol % or less.

The degree of substitution in the second quinonediazide adduct (B2) (percentage of the phenolic hydroxyl group of the second phenol compound substituted with a group having a quinonediazide structure based on all molecules of the quinonediazide adduct (B2)) is preferably It is 20 mol % or more, more preferably 30 mol % or more, still more preferably 40 mol % or more. By setting the degree of substitution to 20 mol % or more, the difference in solubility between the unexposed area and the exposed area can be increased. The degree of substitution may be 100 mol % or less, 95 mol % or less, or 93 mol % or less.

The degree of substitution in the first quinonediazide adduct (B1) is preferably greater than or equal to the degree of substitution in the second quinonediazide adduct (B2).

The phenolic hydroxyl equivalent of the first quinonediazide adduct (B1) is preferably 100-1500, more preferably 130-1400, still more preferably 140-1300. By setting the phenolic hydroxyl equivalent of the first quinonediazide adduct (B1) to 100 or more, dissolution of unexposed areas can be suppressed. By setting the phenolic hydroxyl group equivalent of the first quinonediazide adduct (B1) to 1500 or less, sufficient solubility can be imparted to the exposed areas after exposure.

The phenolic hydroxyl group equivalent of the second quinonediazide adduct (B2) is preferably 180-800, more preferably 180-700, still more preferably 180-600. By setting the phenolic hydroxyl group equivalent of the second quinonediazide 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 quinonediazide adduct (B2) to 800 or less, sufficient solubility can be imparted to the exposed areas after exposure.

The average number of phenolic hydroxyl groups in the first quinonediazide adduct (B1) is preferably 0.1 to 3.0, more preferably 0.2 to 2.5, still more preferably 0.2 to 2.5 per molecule. is 0. By setting the average number of phenolic hydroxyl groups in the first quinonediazide adduct (B1) to 0.1 or more, sufficient solubility can be imparted to the exposed areas after exposure. By setting the average number of phenolic hydroxyl groups in the first quinonediazide adduct (B1) to 3.0 or less, dissolution of unexposed areas can be suppressed.

The average number of phenolic hydroxyl groups in the second quinonediazide adduct (B2) is preferably 0.5 to 5.0, more preferably 1.0 to 4.5, still more preferably 1.0 to 4.5 per molecule. is 0. By setting the average number of phenolic hydroxyl groups in the second quinonediazide adduct (B2) to 0.5 or more, sufficient solubility can be imparted to the exposed areas after exposure. By setting the average number of phenolic hydroxyl groups in the second quinonediazide adduct (B2) to 5.0 or less, dissolution of unexposed areas can be suppressed.

The photosensitive resin composition preferably contains 5 parts by mass to 70 parts by mass, more preferably 8 parts by mass to 60 parts by mass of the first quinonediazide adduct (B1) based on 100 parts by mass of the binder resin (A). It preferably contains 10 parts by mass to 50 parts by mass. When the content of the first quinonediazide adduct (B1) is 5 parts by mass or more based on 100 parts by mass of the binder resin (A), high sensitivity can be achieved. When the content of the first quinonediazide adduct (B1) is 70 parts by mass or less based on 100 parts by mass of the binder resin (A), the alkali developability is good.

The photosensitive resin composition preferably contains 5 parts by mass to 70 parts by mass, more preferably 8 parts by mass to 60 parts by mass of the second quinonediazide adduct (B2) based on 100 parts by mass of the binder resin (A). It preferably contains 10 parts by mass to 50 parts by mass. If the content of the second quinonediazide adduct (B2) is 5 parts by mass or more based on 100 parts by mass of the binder resin (A), high sensitivity can be achieved. If the content of the second quinonediazide adduct (B2) is 70 parts by mass or less based on 100 parts by mass of the binder resin (A), the alkali developability is good.

The mass ratio of the first quinonediazide adduct (B1) to the second quinonediazide adduct (B2) (mass of the first quinonediazide adduct:mass of the second quinonediazide adduct) is preferably 1:13 to 13:1, More preferably 1:10 to 10:1, still more preferably 1:8 to 8:1. By setting the mass ratio to 1:13 to 13:1, the sensitivity of the photosensitive resin composition can be improved.

Without being bound by any theory, in embodiments in which the binder resin (A) comprises the protective resin (a2), the carboxylic acid compound produced from the quinonediazide adduct is the acid decomposable group of the protective resin (a2). It promotes decomposition to regenerate alkali-soluble functional groups such as phenolic hydroxyl groups, thereby increasing the alkali solubility of the protective resin (a2). The quinonediazide adduct interacts with the alkali-soluble functional group of the binder resin (for example, forms a hydrogen bond) before exposure to make the binder resin insoluble in an alkaline aqueous solution. On the other hand, the presence of the alkali-soluble carboxylic acid compound in the irradiated portion makes it easier for the resin in that portion to dissolve in the alkaline aqueous solution together with the carboxylic acid compound. Furthermore, the carboxylic acid compound has a relatively larger molecular structure than acids generated from photoacid generators commonly used in chemically amplified resists, such as p-toluenesulfonic acid and 1-propanesulfonic acid, and diffuses in the film. hard to do. As a result of the synergistic action of these factors, the difference in alkali solubility between the unexposed area and the exposed area can be increased, so that it is possible to form a high-sensitivity and high-resolution pattern even with a low exposure dose.

In embodiments in which the binder resin (A) contains the protective resin (a2), high-resolution patterns can be formed without the post-exposure heat treatment (PEB) required for typical chemically amplified resists. . A quinonediazide adduct has a relatively high quantum yield, and a carboxylic acid compound is efficiently produced in an exposed area. When an acid-decomposable group that can be decomposed by a carboxylic acid compound is present in the surroundings, the generated carboxylic acid compound causes decomposition of the acid-decomposable group even at room temperature to regenerate an alkali-soluble functional group, such as a phenolic hydroxyl group, as a result. , the difference in alkali solubility between the unexposed area and the exposed area can be increased. By omitting PEB, it is possible to suppress deterioration in pattern formability due to excessive diffusion of acid generated from the photo-acid generator into unexposed areas in a high-temperature environment during PEB. Further, when the binder resin (A) contains a resin (a3) having an epoxy group and a phenolic hydroxyl group, if PEB is omitted, ring-opening polymerization of the epoxy group of the resin (a3) having an epoxy group and a phenolic hydroxyl group proceeds. Therefore, the alkali solubility of the resin (a3) having an epoxy group and a phenolic hydroxyl group can be maintained during development.

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

In one embodiment, the black colorant (C) contains a black dye. As a black dye, a dye specified by a color index (C.I.) of Solvent Black 27 to 47 can be used. The black dye is preferably Solvent Black 27, 29 or 34 C.I. I. It is defined by Solvent Black 27-47 C.I. I. When at least one of the dyes defined in (1) is used as the black dye, the light-shielding property of the cured photosensitive resin composition film can be maintained. A photosensitive resin composition containing a black dye has less residue of the black coloring agent (C) during development than a photosensitive resin composition containing a black pigment, and can form a high-definition pattern on a film. .

A black pigment may be used as the black colorant (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 black pigments may also be used. Examples of commercially available perylene-based pigments include K0084, K0086, Pigment Black 21, 30, 31, 32, 33, and 34 from BASF. Examples of commercially available lactam pigments include Irgaphor (registered trademark) black S0100CF manufactured by BASF. The black pigment is preferably at least one selected from the group consisting of carbon black, titanium black, perylene-based pigments, and lactam-based pigments because of its high light-shielding properties.

In one embodiment, the photosensitive resin composition contains 10 parts by mass to 150 parts by mass, preferably 30 parts by mass to 100 parts by mass, more preferably 40 parts by mass of the black colorant (C) based on 100 parts by mass of the binder resin. Contains parts by mass to 70 parts by mass. When the content of the black colorant (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. When the content of the black colorant (C) is 150 parts by mass or less based on the above total of 100 parts by mass, the coating can be colored without impairing the alkali developability.

<Solubilizer (D)>
The photosensitive resin composition may further contain a dissolution accelerator (D) for improving the solubility of the alkali-soluble portion in the developer during development. Examples of the 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. The dissolution accelerator (D) can be used alone or in combination of two or more.

In the present disclosure, "low-molecular-weight compounds" refer to compounds with a molecular weight of 1000 or less. The organic low-molecular compound has a carboxyl group and/or a phenolic hydroxyl group and is alkali-soluble. The organic low-molecular-weight compound may have only a carboxy group, may have only a phenolic hydroxyl group, or may have both a carboxy group and a phenolic hydroxyl group. The total number of carboxy groups and phenolic hydroxyl groups contained in one molecule of the organic low-molecular-weight compound is preferably 2 or more.

Examples of such organic low-molecular-weight 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; acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, brassylic acid, methylmalonic acid, ethylmalonic acid, dimethylmalonic acid, methylsuccinic acid, tetramethylsuccinic acid, citraconic acid, etc. Aliphatic dicarboxylic acids; aliphatic tricarboxylic acids such as tricarballylic acid, aconitic acid and camphoronic acid; aromatic monocarboxylic acids such as benzoic acid, toluic acid, cumic acid, hemimelitic acid and mesitylene acid; phthalic acid, isophthalic acid, Aromatic polycarboxylic acids such as terephthalic acid, trimellitic acid, trimesic acid, merophanic acid and pyromellitic acid; aromatic hydroxycarboxylic acids such as dihydroxybenzoic acid, trihydroxybenzoic acid and gallic acid; phenylacetic acid, hydroatropic acid, hydrosilicic acid Other carboxylic acids such as mic acid, mandelic acid, phenylsuccinic acid, atropic acid, cinnamic acid, methyl cinnamate, benzyl cinnamate, cinnamylideneacetic acid, coumaric acid, umberic acid; catechol, resorcinol, hydroquinone, 1, Aromatic polyols such as 2,4-benzenetriol, pyrogallol, phloroglucinol, bisphenol and the like are included.

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 part by mass to 35 parts by mass, based on 100 parts by mass of the binder resin. parts, more preferably 2 parts by mass to 20 parts by mass. If the content of the dissolution accelerator (D) is 0.1 parts by mass or more based on the above total of 100 parts by mass, the dissolution of the resin component can be effectively promoted, and if it is 50 parts by mass or less Excessive dissolution of the resin component can be suppressed, and the pattern formability, surface quality, etc. of the film can be improved.

<Optional component (E)>
The photosensitive resin composition can contain a thermosetting agent, a surfactant, a coloring agent other than the black coloring agent (C), and the like as an optional component (E). For purposes of this disclosure, optional component (E) is defined as none of (A)-(D).

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

The content of the heat curing agent is preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and still more preferably 3 parts by mass or less, based on the total 100 parts by mass of solid content excluding the heat curing agent. .

The photosensitive resin composition can contain a surfactant, for example, to improve coatability, to improve the smoothness of the coating, or to improve the developability of the coating. Examples of surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether and polyoxyethylene oleyl ether; Ethylene aryl ether; Nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; Megafac (registered trademark) F-251, F-281, F-430, F- 444, R-40, F-553, F-554, F-555, F-556, F-557, F-558, F-559 (trade names, manufactured by DIC Corporation), Surflon (registered trademark) Fluorinated surfactants such as S-242, S-243, S-386, S-420, S-611 (trade names, manufactured by AGC Seimi Chemical Co., Ltd.); and organosiloxane polymers KP323, KP326, and KP341 (these are trade names, manufactured by Shin-Etsu Chemical Co., Ltd.). These surfactants can be used alone or in combination of two or more.

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

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

Examples of dyes include azo dyes, benzoquinone dyes, naphthoquinone dyes, anthraquinone dyes, cyanine dyes, squarylium dyes, croconium dyes, merocyanine dyes, stilbene dyes, diphenylmethane dyes, and triphenylmethane dyes. 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 (registered trademark) RED 3312 (a red dye specified by C.I. of Solvent Red 122, manufactured by Orient Chemical Industry Co., Ltd.), and VALIFAST (registered trademark) RED 3311 (of Solvent Red 8). red dyes defined by C.I., manufactured by Orient Chemical Industry Co., Ltd.).

As pigments, for example, C.I. I. Pigment Yellow 20, 24, 86, 93, 109, 110, 117, 125, 137, 138, 147, 148, 153, 154, 166, C.I. I. Pigment Orange 36, 43, 51, 55, 59, 61, C.I. I. Pigment Red 9, 97, 122, 123, 149, 168, 177, 180, 192, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, C.I. I. pigment violet 19, 23, 29, 30, 37, 40, 50, C.I. I. Pigment Blue 15, 15:1, 15:4, 22, 60, 64, C.I. I. Pigment Green 7, and C.I. I. Pigment Brown 23, 25, 26 can be mentioned.

[Coating composition]
<Solvent (F)>
The photosensitive resin composition can be dissolved in the solvent (F) and used as a coating composition in a solution state (when a black pigment is contained, the pigment is in a dispersed state). For example, a first quinonediazide adduct (B1), a second quinonediazide adduct (B2), a black colorant (C), and a necessary A coating composition containing a photosensitive resin composition can be prepared by mixing an optional component (E) such as a dissolution accelerator (D), a heat curing agent, and a surfactant in a predetermined ratio according to the . The coating composition can be adjusted to a viscosity suitable for the coating method used by varying the amount of solvent (F).

Examples of the solvent (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. Diethylene glycol compounds such as monomethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether; Propylene glycol monoalkyl ether acetate compounds such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate; 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; ethyl 2-hydroxypropionate, 2-hydroxy-2-methylpropion methyl acid, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-2-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionate Esters such as methyl acid, ethyl 3-ethoxypropionate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone; and N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethyl Amide compounds such as acetamide are included. These solvents can be used alone or in combination of two or more.

The solid content concentration of the coating composition can be appropriately determined depending on the purpose of use. For example, the coating composition may have a solids concentration of 1 to 60% by weight, 3 to 50% by weight, or 5 to 40% by weight.

A well-known method can be used for the method of dispersing and mixing when using a pigment. For example, ball mills, sand mills, bead mills, paint shakers and rocking mills; blade types such as kneaders, paddle mixers, planetary mixers and Henschel mixers; roll types such as three-roll mixers; An ultrasonic wave, a homogenizer, a rotation/revolution mixer, etc. may be used. It is preferable to use a bead mill from the viewpoint of dispersion efficiency and fine dispersion.

The prepared coating composition is usually filtered before use. Filtration means include, for example, a Millipore filter with a pore size of 0.05 to 1.0 μm.

The coating composition prepared in this way also has excellent long-term storage stability.

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

After applying the coating composition to the substrate surface, the solvent is usually removed by heating to form a film (pre-bake). The heating conditions vary depending on the type and blending ratio of each component, but usually at 70 to 130° C., for example, 30 seconds to 20 minutes on a hot plate and 1 to 60 minutes in an oven to obtain a coating. can be done.

Next, the pre-baked film is irradiated with radiation (for example, visible light, ultraviolet light, deep 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 250-450 nm. In one embodiment, the radiation is i-line. In another embodiment, the radiation is ghi rays.

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

After the exposure process or the PEB process, the coating is developed by contacting it with a developer, and unnecessary portions are removed to form a pattern on the coating (development process). Examples of the developer include inorganic alkali compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as n-propylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; quaternary amines such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and choline. ammonium salts; pyrrole, piperidine, 1,8-diazabicyclo[5.4.0]-7-undecene, cyclic amines such as 1,5-diazabicyclo[4.3.0]-5-nonane, etc. Aqueous solutions can be used. An aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant, or the like to an alkaline aqueous solution can also be used as a developer. Development time is usually 30 to 180 seconds. The developing method may be any one of a liquid swell method, a shower method, a dipping method, and the like. After development, the coating can be patterned by washing with running water for 30 to 90 seconds, removing unnecessary portions, and air-drying with compressed air or compressed nitrogen.

Thereafter, the film having the pattern formed thereon is subjected to heat treatment at 100 to 350° C. for 20 to 200 minutes using a heating device such as a hot plate or oven to obtain a cured film (post-baking, heat treatment process). In the heat treatment, the temperature may be maintained constant, may be increased continuously, or may be increased stepwise. Heat treatment is preferably performed in a nitrogen atmosphere.

The optical density (OD value) of the cured film of the photosensitive resin composition is preferably 0.5 or more, more preferably 0.7 or more, and preferably 1.0 or more per 1 μm of film thickness. More preferred. If the cured film has an OD value of 0.5 or more per 1 μm of film thickness, sufficient light shielding properties can be obtained.

A method for producing an organic EL element partition wall or an organic EL element insulating film of one embodiment includes dissolving or dispersing a photosensitive resin composition in a solvent to prepare a coating composition, applying the coating composition to a substrate, Forming a coating, removing the solvent contained in the coating and drying the coating, irradiating the dried coating with radiation through a photomask to expose the coating, and contacting the exposed coating with a developer forming a pattern on the coating by developing with a liquid, and heat-treating the coating with the pattern formed at a temperature of 100° C. to 350° C. to form an organic EL element partition wall or an insulating film. The above PEB can also be performed after exposure and before development.

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

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

One embodiment is an organic EL device containing a cured product of a photosensitive resin composition.

The present invention will be specifically described below based on examples and comparative examples, but the present invention is not limited to these examples.

(1) Raw Materials Raw materials used in Examples and Comparative Examples were manufactured or obtained as follows.

The weight-average molecular weight and number-average molecular weight of each resin contained in the binder resin (A) were calculated using a calibration curve prepared using a polystyrene standard substance under the following measurement conditions.
Apparatus name: Shodex (registered trademark) GPC-101
Column: Shodex® LF-804
Mobile phase: Tetrahydrofuran Flow rate: 1.0 mL/min Detector: Shodex (registered trademark) RI-71
Temperature: 40°C

[Production Example 1] Production of copolymer (a1) (PCX-02e) of polymerizable monomer having phenolic hydroxyl group and other polymerizable monomer 4-hydroxyphenyl methacrylate ("PQMA" manufactured by Showa Denko K.K. ”) 29.0 g and N-cyclohexylmaleimide (manufactured by Nippon Shokubai Co., Ltd.) 5.12 g, 1-methoxy-2-propyl acetate (manufactured by Daicel Co., Ltd.) 96.5 g as a solvent, V as a polymerization initiator 3.41 g of -601 (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was completely dissolved in 13.7 g of 1-methoxy-2-propyl acetate (manufactured by Daicel Corporation). The resulting two solutions were simultaneously added to 40.0 g of 1-methoxy-2-propyl acetate (manufactured by Daicel Co., Ltd.) heated to 85° C. in a 300 mL three-necked flask under a nitrogen gas atmosphere for 2 hours. It was added dropwise and then reacted at 85° C. for 3 hours. The reaction solution cooled to room temperature was dropped into 815 g of toluene to precipitate a copolymer. The precipitated copolymer was collected by filtration and vacuum-dried at 90° C. for 4 hours to collect 32.4 g of white powder. The obtained PCX-02e had a number average molecular weight of 3,100 and a weight average molecular weight of 6,600.

[Production Example 2] Production of protective resin (a2) (PCX-02e-THF55) in which a phenolic hydroxyl group is protected with a 2-tetrahydrofuranyl group In a 100 mL three-necked flask, a polymerizable unit having a phenolic hydroxyl group was 10.0 g of a copolymer (a1) (PCX-02e) of a monomer and other polymerizable monomers, and 0.60 g of a pyridinium salt of p-toluenesulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) as an acid catalyst. , and 50.0 g of tetrahydrofuran (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.). After cooling with ice in a nitrogen gas atmosphere, 6.69 g of 2,3-dihydrofuran (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 1 hour. After that, the mixture was stirred at room temperature for 16 hours. After neutralizing the acid catalyst with saturated sodium bicarbonate aqueous solution, the water layer was removed. Furthermore, the organic layer was washed twice with water. The tetrahydrofuran was then distilled off. The resulting 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 recovered by filtration and vacuum dried at 80° C. for 4 hours to recover 11.0 g of white powder. The resulting powder was dissolved in propylene glycol monomethyl ether acetate to obtain a 20 mass% solids solution of the protective resin (a2) (PCX-02e-THF55) in which the phenolic hydroxyl group was protected with a 2-tetrahydrofuranyl group. . The resulting 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 with acid-decomposable groups of 55 mol%, and at least one phenolic hydroxyl group being acid-decomposable. The number of structural units represented by formula (4) protected by groups was 55% of the total number of structural units of PCX-02e-THF55. The proportion of phenolic hydroxyl groups protected with acid-decomposable groups was determined using a thermogravimetric differential thermal analyzer (TG/DTA6200, manufactured by Hitachi High-Tech Science Co., Ltd.) in a nitrogen gas stream at a temperature elevation rate of 10°C/min. The weight loss rate of PCX-02e-THF55 at 260 ° C. when the temperature is raised from room temperature to 250 ° C. under the conditions, held for 10 minutes, and further heated to 400 ° C. at a temperature increase rate of 10 ° C./min ( %).

[Production Example 3] Production of resin (a3) (N695OH70) having an epoxy group and a phenolic hydroxyl group 75.2 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) as a solvent in a 300 mL three-necked flask, per molecule As a compound having at least two epoxy groups, 42.8 g of EPICLON (registered trademark) N-695 (a cresol novolac type epoxy resin manufactured by DIC Corporation, epoxy equivalent of 214) was charged and dissolved at 60°C in 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 equivalent of epoxy), and triphenylphosphine (Tokyo Chemical Industry Co., Ltd.) as a reaction catalyst. Kogyo Co., Ltd.) was added (0.166 g (0.633 mmol)) and reacted at 110° C. for 21 hours. The reaction solution was returned to room temperature, diluted with γ-butyrolactone to a solid content of 20% by mass, and filtered to obtain 304.2 g of a solution of resin (a3) (N695OH70) having epoxy groups and phenolic hydroxyl groups. The obtained reactant had a number average molecular weight of 3,000, a weight average molecular weight of 7,500, and an epoxy equivalent of 2,200.

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

<Quinone diazide adduct (B)>
A compound shown in Table 1 was used as the quinonediazide adduct (B).

Table 2 shows the structural formula of the quinonediazide adduct (B). In the structural formula, R is a hydrogen atom or

represents

<Black colorant (C)>
As the black colorant (C), a black dye, VALIFAST (registered trademark) BLACK 3820 (black dye defined by C.I. of Solvent Black 27, manufactured by Orient Chemical Industry Co., Ltd.) was used.

<Solubilizer (D)>
Phloroglucinol was used as a dissolution enhancer (D).

<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 the solvent (F).

(2) Evaluation methods Evaluation methods used in Examples and Comparative Examples are as follows.

[sensitivity]
A photosensitive resin composition was bar-coated on a glass substrate (size 100 mm×100 mm×1 mm) to a dry film thickness of 1.5 μm, and prebaked by heating on a hot plate at 100° C. for 1 minute. The film was exposed through a quartz photomask (having an opening pattern of φ10 μm) with an exposure apparatus (trade name: Multilight ML-251A/B, manufactured by Ushio Inc.) incorporating an ultra-high pressure mercury lamp. The amount of exposure was measured using an ultraviolet integrating photometer (trade name: UIT-150 light receiving unit UVD-S365, manufactured by Ushio Inc.). After the exposure, alkaline development was carried out for 60 seconds with a 2.38% by mass tetramethylammonium hydroxide aqueous solution using a spin developing device (AD-1200, manufactured by Takizawa Sangyo Co., Ltd.). The above procedure was repeated while changing the exposure dose, and the minimum irradiation dose (mJ/cm ² ) at which a pattern with a hole diameter of 10 μm could be formed after development was defined as the sensitivity.

[OD value of cured film]
The photosensitive resin composition was spin-coated on a glass substrate (size 100 mm×100 mm×1 mm) to a dry film thickness of about 1.5 μm, and heated on a hot plate at 120° C. for 80 seconds to dry the solvent. After that, the coating was obtained by curing at 250° C. for 60 minutes in a nitrogen gas atmosphere. The OD value of the cured film was measured with a transmission densitometer (BMT-1, manufactured by Sakata Inx Engineering Co., Ltd.), corrected with the OD value of the glass alone, and converted to an OD value per 1 μm of film thickness. The thickness of the coating was measured using an optical film thickness measuring device (F20-NIR, manufactured by Filmetrics Co., Ltd.).

(3) Preparation and evaluation of photosensitive resin composition [Examples 1 to 12 and Comparative Examples 1 to 3]
The binder resin (A) with the composition shown in Table 3 was mixed and dissolved, and the quinonediazide adduct (B) shown in Table 3, the black colorant (C), and the dissolution accelerator (D) were added to the resulting solution. , and GBL/PGMEA mixed solvent (F) were added and further mixed. After visually confirming that the components were dissolved, the solution was filtered through a Millipore filter having a pore size of 0.22 μm to prepare a photosensitive resin composition having a solid concentration of 12% by mass. The mass parts of the compositions in Table 3 are solid content conversion values. Table 3 shows the evaluation results of the photosensitive resin compositions of Examples 1 to 12 and Comparative Examples 1 to 3.

When comparing Examples 1 to 11 in which the binder resin (A) contains PCX-02e-THF55, which is the protective resin (a2), and Comparative Examples 1 and 3, Examples 1 to 11 have higher sensitivity (the amount of exposure is less )Met. Further, when comparing Example 12 in which the binder resin (A) does not contain PCX-02e-THF55, which is the protective resin (a2), and Comparative Example 2, Example 12 has higher sensitivity (less exposure). Met.

The photosensitive resin composition according to the present disclosure can be suitably used for radiation lithography for forming partition walls or insulating films of organic EL elements. An organic EL element provided with a partition wall or an insulating film formed from the photosensitive resin composition according to the present disclosure is suitably used as an electronic component of a display device exhibiting good contrast.

Claims

(A) a binder resin;
(B1) a first quinonediazide adduct that is a quinonediazide adduct to a first phenol compound;
(B2) a second quinonediazide adduct that is a quinonediazide adduct to a second phenol compound;
(C) a photosensitive resin composition containing a black colorant, wherein the difference between the molecular weight of the first phenolic compound and the molecular weight of the second phenolic compound is 40 to 500, and A photosensitive resin composition having a molecular weight smaller than that of the second phenol compound.
The photosensitive resin composition according to claim 1, wherein each of said first phenolic compound and said second phenolic compound has three or more phenolic hydroxyl groups.
3. The photosensitive resin according to claim 1, wherein the first quinonediazide adduct has a phenolic hydroxyl equivalent of 100 to 1500, and the second quinonediazide adduct has a phenolic hydroxyl equivalent of 180 to 800. Composition.
The average number of phenolic hydroxyl groups per molecule of the first quinonediazide adduct is 0.1 to 3.0, and the average number of phenolic hydroxyl groups of the second quinonediazide adduct is 0.5 to 5.0 per molecule. 0, the photosensitive resin composition according to any one of claims 1 to 3.
5. Any one of claims 1 to 4, wherein said first quinonediazide adduct is 1,2-naphthoquinonediazide-4-sulfonate or 1,2-naphthoquinonediazide-5-sulfonate of said first phenol compound. 1. The photosensitive resin composition according to item 1.
6. Any one of claims 1 to 5, wherein said second quinonediazide adduct is 1,2-naphthoquinonediazide-4-sulfonate or 1,2-naphthoquinonediazide-5-sulfonate of said second phenol compound. 1. The photosensitive resin composition according to item 1.
The photosensitive resin composition according to any one of claims 1 to 6, wherein the first phenol compound has a molecular weight of 230 or more and less than 300, and the second phenol compound has a molecular weight of 300 or more and 600 or less.
Any one of claims 1 to 7, comprising 5 to 70 parts by mass of the first quinonediazide adduct and 5 to 70 parts by mass of the second quinonediazide adduct based on 100 parts by mass of the binder resin. 1. The photosensitive resin composition according to item 1.
Claims 1 to 1, wherein the mass ratio of the first quinonediazide adduct to the second quinonediazide adduct (mass of the first quinonediazide adduct:mass of the second quinonediazide adduct) is 1:13 to 13:1. 9. The photosensitive resin composition according to any one of 8.
The binder resin contains a polymerizable monomer having an alkali-soluble functional group and a copolymer of other polymerizable monomers, and the polymerizable monomer having an alkali-soluble functional group and the other polymerizable monomer. A copolymer of the formula (1)

(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.)
Having a structural unit represented by, the photosensitive resin composition according to any one of claims 1 to 9.
The binder resin contains a resin having an epoxy group and a phenolic hydroxyl group, and the resin having an epoxy group and a phenolic hydroxyl group reacts a compound having at least two epoxy groups in one molecule with a hydroxybenzoic acid compound. , and the formula (7)

(In the formula (7), b is an integer of 1 to 5, and * represents the bonding portion of the compound having at least two epoxy groups in one molecule with the residue excluding the epoxy group involved in the reaction. .)
The photosensitive resin composition according to any one of claims 1 to 10, which is a compound having a structure of
The photosensitive resin composition according to claim 11, wherein the compound having at least two epoxy groups in one molecule is a novolak type epoxy resin.
The binder resin has the formula (4)

(In formula (4), R 9 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R 10 is an acid-decomposable group, r is an integer of 0 to 5, s is 0 to 5 is an integer of , where r + s is an integer of 1 to 5.)
The resin according to any one of claims 1 to 12, comprising a resin having at least one structural unit represented by formula (4), wherein s is an integer of 1 or more. A photosensitive resin composition.
The photosensitive resin composition according to any one of claims 1 to 13, wherein the cured film of the photosensitive resin composition has an optical density (OD value) of 0.5 or more per 1 µm of film thickness.
The photosensitive resin composition according to any one of claims 1 to 14, wherein the black colorant is a dye defined by a color index (C.I.) of Solvent Black 27 to 47.
The photosensitive resin composition according to any one of claims 1 to 15, comprising 10 to 150 parts by mass of said black colorant based on 100 parts by mass of said binder resin.
An organic EL element partition comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 16.
An organic EL element insulating film containing a cured product of the photosensitive resin composition according to any one of claims 1 to 16.
An organic EL device comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 16.