KR20230160163A - Negative-type photosensitive resin composition - Google Patents

Abstract

A curable composition is provided that has alkali solubility, can suppress the occurrence of film forming defects, enables low-temperature curing, and produces a cured film with excellent chemical resistance.
A negative photosensitive resin composition containing the following components (A) to (D). (A) Molar ratio of the structural unit derived from m-cresol (a1), the structural unit derived from benzaldehyde (a2), and the structural unit derived from salicylaldehyde (a3) [(a1):(a2):(a3) )] A, 1.0:0.4~0.8:0.3~0.6 novolac type phenolic resin/(B) polyimide containing ethylenically unsaturated group, polyimide precursor containing ethylenically unsaturated group, polybenzoxazole containing ethylenically unsaturated group, and At least one resin selected from ethylenically unsaturated group-containing polybenzoxazole precursors/(C) photosensitizer/(D) solvent

Description

Negative photosensitive resin composition {NEGATIVE-TYPE PHOTOSENSITIVE RESIN COMPOSITION}

The present invention relates to a negative photosensitive resin composition, a cured film, and a resist film.

As a next-generation flat panel display, organic EL displays are attracting attention. An organic EL display is a self-luminous display device that uses electroluminescence from organic compounds, and is capable of displaying images with a high angle view and high-speed response. Additionally, it is possible to reduce thickness and weight. In recent years, as organic EL displays have become more precise, further miniaturization of light-emitting elements has been required.

In an organic EL display, an element emits light using energy from the recombination of electrons injected from the cathode and holes injected from the anode. Therefore, if a substance that forms an energy level that inhibits the recombination of electrons and holes exists, the luminous efficiency of the light-emitting element decreases, and the lifespan of the organic EL display decreases. On the other hand, in order to generally divide the pixels of a light emitting device, an insulating layer called a pixel dividing layer is formed between the transparent electrode on the light extraction side and the metal electrode on the opposite side. Since this pixel split layer is formed at a position adjacent to the light emitting element, outgassing or outflow of ion components from the pixel split layer may be a factor in reducing the lifespan of the organic EL display. For this reason, heat resistance and durability are required for the pixel dividing layer.

From the viewpoint of high heat resistance, a positive photosensitive resin composition using polyimide or polybenzoxazole is used as the material of the pixel division layer (for example, patent document 1). However, since the pixel split layer using the positive photosensitive resin composition contains a naphthoquinonediazide compound as a photosensitive agent, degassing occurs from the pixel split layer, which is a factor that reduces the lifespan of the organic EL display. do.

Therefore, a method of forming a pixel division layer using a negative photosensitive resin composition that does not use naphthoquinonediazide is being studied (for example, patent document 2). However, with the negative resist described in Patent Document 2, sufficient alkali developability and low-temperature curing properties cannot be obtained, and there are problems such as generation of residue (scum) after development, sagging of the divided layer after heat treatment, and low solvent resistance. .

As described above, as organic EL displays become more refined, there is a demand for photosensitive resin compositions that can draw finer pixel division layers without generating residues and also have low-temperature curability and chemical resistance.

US Patent Application Publication No. 2002/162998 Specification International Publication No. 2017/159876

The purpose of the present invention is to provide a curable composition that has alkali solubility, can suppress the occurrence of film forming defects, is capable of curing at low temperatures, and yields a cured film with excellent chemical resistance.

As a result of intensive studies to solve the above problems, the present inventors have found that a novolak-type phenol resin composition having a specific structural unit, and at least one of an ethylenically unsaturated group-containing polyimide and an ethylenically unsaturated group-containing polybenzoxazole are available. It was discovered that a negative photosensitive resin composition used in combination has high alkali solubility in unexposed areas, can suppress the occurrence of film forming defects, allows low-temperature curing after development, and produces a cured film with excellent chemical resistance. The invention was completed.

That is, the present invention relates to a negative photosensitive resin composition containing the following components (A) to (D).

(A) Molar ratio of the structural unit derived from m-cresol (a1), the structural unit derived from benzaldehyde (a2), and the structural unit derived from salicylaldehyde (a3) [(a1):(a2):(a3) )], 1.0:0.4~0.8:0.3~0.6 novolac type phenol resin

(B) one or more resins selected from polyimide containing an ethylenically unsaturated group, polyimide precursor containing an ethylenically unsaturated group, polybenzoxazole containing an ethylenically unsaturated group, and polybenzoxazole precursor containing an ethylenically unsaturated group

(C) Photosensitizer

(D) Solvent

The present invention also relates to a cured film obtained from the negative photosensitive resin composition.

The present invention also relates to a resist film obtained from the negative photosensitive resin composition.

According to the present invention, it is possible to provide a curable composition that has alkali solubility, can suppress the occurrence of film forming defects, enables low-temperature curing, and produces a cured film with excellent chemical resistance.

Figure 1 is a GPC chart of the novolak-type phenol resin obtained in Synthesis Example 1.
Figure 2 is a GPC chart of the novolak-type phenolic resin obtained in Synthesis Example 2.
Figure 3 is a GPC chart of the novolak-type phenolic resin obtained in Synthesis Example 3.
Figure 4 is a GPC chart of the novolak-type phenolic resin obtained in Synthesis Example 4.
Figure 5 is a GPC chart of the novolak-type phenol resin obtained in Preparation Example 1.

The modes for carrying out the invention will be described below.

In addition, in this specification, “x~y” shall indicate the numerical range of “x or more and y or less.” The upper and lower limits described with respect to the numerical range can be arbitrarily combined.

In addition, a form in which two or more individual forms of the present invention described below are combined is also a form of the present invention.

[Negative photosensitive resin composition]

The negative photosensitive resin composition according to one embodiment of the present invention contains the following components (A) to (D).

(A) Molar ratio of the structural unit derived from m-cresol (a1), the structural unit derived from benzaldehyde (a2), and the structural unit derived from salicylaldehyde (a3) [(a1):(a2):(a3) )], 1.0:0.4~0.8:0.3~0.6 novolac type phenol resin

(B) one or more resins selected from polyimide containing an ethylenically unsaturated group, polyimide precursor containing an ethylenically unsaturated group, polybenzoxazole containing an ethylenically unsaturated group, and polybenzoxazole precursor containing an ethylenically unsaturated group

(C) Photosensitizer

(D) Solvent

In this embodiment, by using the novolak-type phenol resin (A) and the resin (B) in combination, the compatibility of both resins is improved. For this reason, the occurrence of film forming defects can be suppressed. In addition, the resin composition has high alkali solubility in the unexposed area, enables low-temperature curing after development, and produces a cured film with excellent chemical resistance.

Hereinafter, the components of the negative photosensitive resin composition will be described.

· Ingredient (A)

The novolak-type phenolic resin as component (A) has a molar ratio [( a1):(a2):(a3)] is 1.0:0.4~0.8:0.3~0.6.

The molar ratio of the structural unit (a1) derived from m-cresol, the structural unit (a2) derived from benzaldehyde, and the structural unit (a3) derived from salicylaldehyde of component (A) [(a1):(a2) :(a3)] is preferably 1.0:0.5 to 0.7:0.3 to 0.5, more preferably 1.0:0.55 to 0.65:0.35 to 0.45, from the viewpoint of obtaining a cured film that has chemical resistance at low temperature curing in addition to high sensitivity. am.

Component (A) may contain structural units other than the structural unit (a1) derived from m-cresol, the structural unit (a2) derived from benzaldehyde, and the structural unit (a3) derived from salicylaldehyde. Structural units other than (a1) to (a3) include structural units derived from phenols and aldehydes other than m-cresol, benzaldehyde, and salicylaldehyde.

Examples of the phenols include phenol, o-cresol, p-cresol, 2,3-xylenol, 2,5-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3, 5-trimethylphenol, 3,4,5-trimethylphenol, etc. are mentioned.

Examples of the aldehydes include formalin, paraformaldehyde, acetaldehyde, chloroacetaldehyde, 4-hydroxybenzaldehyde, and 3-hydroxybenzaldehyde.

The total content of the structural units (a1), (a2), and (a3) in component (A) is preferably 30% by mass from the viewpoint of obtaining a cured film that has high sensitivity and chemical resistance by low-temperature curing. or more, more preferably 50 mass% or more, and even more preferably 90 mass% or more.

The total content of the structural units (a1), (a2), and (a3) may be substantially 100% by mass. In addition, substantially 100% by mass means the case where structural units other than the above structural units (a1), (a2), and (a3) are inevitably included.

The weight average molecular weight of the novolak-type phenol resin as component (A) is preferably 1,000 or more, more preferably 1,500 or more. Additionally, it is preferably 7,000 or less, more preferably 6,000 or less, and even more preferably 5,000 or less. A weight average molecular weight of 1,000 or more is preferable because it has high heat resistance. On the other hand, a weight average molecular weight of 7,000 or less is preferable because of high sensitivity. In addition, in this specification, the weight average molecular weight is measured according to the conditions described in the examples.

The novolak-type phenol resin as component (A) preferably has a molecular weight of less than 500 in an area ratio of less than 3.0% by mass as measured by gel permeation chromatography. By reducing the low molecular weight components of the novolak-type phenol resin with a molecular weight of less than 500, alkali solubility can be further improved.

The lower limit of the component having a molecular weight of less than 500 of the novolak-type phenol resin is not particularly limited, but is, for example, 0.0% by mass or more, 0.1% by mass or more, or 0.3% by mass or more.

That the proportion of components with a molecular weight of less than 500 in the novolak-type phenol resin is less than 3.0 mass% is confirmed by gel permeation chromatography (GPC) measurement described in the Examples.

It is possible to reduce the component with a molecular weight of less than 500 to less than 3.0% by mass of the novolak-type phenol resin, for example, by further reprecipitating the novolak-type phenol resin obtained by the production method described later. Specifically, the novolak-type phenol resin is dissolved in a good solvent (e.g., methyl isobutyl ketone), and then a poor solvent (e.g., heptane) is added to produce novolak-type phenol. The resin is reprecipitated. By performing this operation multiple times, the component with a molecular weight of less than 500 can be reduced to less than 3.0 mass%.

Component (A) is an acid catalyst containing m-cresol, benzaldehyde, and salicylaldehyde in an organic solvent at a molar ratio (m-cresol:benzaldehyde:salicylicaldehyde) of 1.0:0.4 to 0.8:0.3 to 0.6. It is obtained by polycondensation using

The molar ratio of m-cresol, benzaldehyde, and salicylaldehyde (m-cresol:benzaldehyde:salicylaldehyde) in the organic solvent is preferably 1.0 from the viewpoint of obtaining a cured film with high sensitivity and chemical resistance through low-temperature curing: It is in the range of 0.5 to 0.7:0.3 to 0.5, more preferably 1.0:0.55 to 0.65:0.35 to 0.45.

It is preferable that the molar ratio of benzaldehyde is smaller than the molar ratio of salicylaldehyde. In other words, it is preferable if benzaldehyde < salicylaldehyde (molar ratio) is satisfied.

When m-cresol, benzaldehyde, and salicylaldehyde are polycondensed in an organic solvent to obtain the novolak-type phenolic resin as component (A), as described above, phenols other than m-cresol, benzaldehyde, and salicylaldehyde are added. and aldehydes may be contained in the organic solvent.

In addition to high sensitivity, the ratio of the total mass of m-cresol, benzaldehyde, and salicylaldehyde to the total mass of all starting materials that can become structural units of component (A) in the organic solvent is From the viewpoint of obtaining a cured film with chemical properties, it is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably substantially 100% by mass.

Organic solvents used in the production of component (A) include, for example, methanol, ethanol, 1-propanol, 2-propanol, butanol, hexanol, ethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, Examples include methyl ethyl ketone, methyl isobutyl ketone, and toluene. Among these, at least one selected from ethanol, 1-propanol, and 2-propanol is preferable, and ethanol is more preferable.

The amount of the organic solvent used is preferably 20 parts by mass or more, more preferably 50 parts by mass or more, with respect to 100 parts by mass of the raw material for deriving the structural unit constituting the component (A), from the viewpoint of uniformity of reaction. am. Moreover, it is preferably 500 parts by mass or less, more preferably 300 parts by mass or less.

Examples of the acid catalyst used in producing component (A) include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and boric acid; Examples include organic acids such as oxalic acid, acetic acid, and p-toluenesulfonic acid. Among these, in order to further promote the reaction, inorganic acids and p-toluenesulfonic acid are preferable, and p-toluenesulfonic acid is more preferable.

The amount of the acid catalyst added is not particularly limited, but is preferably 5 parts by mass or more, more preferably 20 parts by mass or more, with respect to 100 parts by mass of the raw material for deriving the structural unit constituting component (A). Moreover, it is preferably 150 parts by mass or less, and more preferably 100 parts by mass or less.

The reaction temperature when polycondensing the raw material of component (A) is preferably 30°C or higher, more preferably 40°C or higher, because it promotes the reaction and can efficiently increase the molecular weight. Additionally, it is preferably 100°C or lower, and more preferably 80°C or lower.

The reaction time is preferably 4 hours or more, more preferably 12 hours or more. Moreover, it is preferably 32 hours or less, more preferably 24 hours or less.

· Ingredient (B)

Component (B) is one or more resins selected from ethylenically unsaturated group-containing polyimide, ethylenically unsaturated group-containing polyimide precursor, ethylenically unsaturated group-containing polybenzoxazole, and ethylenically unsaturated group-containing polybenzoxazole precursor. am. Component (B) is a polyimide, a polyimide precursor, polybenzoxazole, or a polybenzoxazole precursor in which an ethylenically unsaturated group is introduced. Component (B) can be one that has been conventionally used in photosensitive resin compositions.

<Polyimide and polyimide precursor>

Examples of polyimide precursors include those obtained by reacting tetracarboxylic acid, the corresponding tetracarboxylic acid dianhydride, or tetracarboxylic acid diester dichloride, with diamine, the corresponding diisocyanate compound, or trimethylsilylated diamine, and tetracarboxylic acid. and/or its derivative residues, and diamine and/or its derivative residues. Examples of polyimide precursors include polyamic acid, polyamic acid ester, polyamic acid amide, or polyisoimide.

Examples of polyimides include those obtained by dehydrating and ring-closing the above-mentioned polyamic acid, polyamic acid ester, polyamic acid amide, or polyisoimide by heating or reaction using an acid or base, etc. It has a residue of tetracarboxylic acid and/or its derivative, and a residue of diamine and/or its derivative.

The tetracarboxylic dianhydride used in the synthesis of polyimide is preferably pyromellitic anhydride from the viewpoint of heat resistance. The diamine used in the synthesis of polyimide is preferably 4,4-diaminodiphenyl ether from the viewpoint of heat resistance.

The unsaturated group-containing polyimide and the unsaturated group-containing polyimide precursor used in the present invention have the above-mentioned polyimide or polyimide precursor and an ethylenically unsaturated group as a radical polymerizable group. By having an ethylenically unsaturated group, sensitivity during exposure can be improved. As the unsaturated group-containing polyimide and the unsaturated group-containing polyimide precursor, those obtained by reacting the phenolic hydroxyl group and/or carboxyl group of the polyimide and a part of the polyimide precursor with a compound having an ethylenically unsaturated group described later are preferable. Through the above reaction, it becomes possible to introduce an ethylenically unsaturated group into the resin.

<Polybenzoxazole and polybenzoxazole precursor>

Examples of the polybenzoxazole precursor include those obtained by reacting a dicarboxylic acid, the corresponding dicarboxylic acid dichloride or dicarboxylic acid activated diester, and a bisaminophenol compound as a diamine, and the dicarboxylic acid and/or its It has a derivative residue and a bisaminophenol compound and/or its derivative residue. Examples of polybenzoxazole precursors include polyhydroxyamide.

Polybenzoxazole is, for example, obtained by dehydrating and ring-closing a dicarboxylic acid and a bisaminophenol compound as a diamine through a reaction using polyphosphoric acid, or the polyhydroxyamide described above is heated or dissolved in phosphoric acid anhydride or a base. Alternatively, it may be obtained by dehydration and ring closure through a reaction using a carboxyimide compound or the like, and has a dicarboxylic acid and/or its derivative residue and a bisaminophenol compound and/or its derivative residue.

The bisaminophenol used in the synthesis of polybenzoxazole is preferably 3,3-hydroxybenzidine from the viewpoint of heat resistance. The dicarboxylic acid used in the synthesis of polybenzoxazole is preferably 4,4-biphenyldicarboxylic acid from the viewpoint of heat resistance.

The ethylenically unsaturated group-containing polybenzoxazole and the ethylenically unsaturated group-containing polybenzoxazole precursor used in the present invention have an ethylenically unsaturated group as a radical polymerizable group. By having an ethylenically unsaturated group, sensitivity during exposure can be improved. As polybenzoxazole containing an ethylenically unsaturated group and a polybenzoxazole precursor containing an ethylenically unsaturated group, polybenzoxazole and a part of the polybenzoxazole precursor have a phenolic hydroxyl group and/or a carboxyl group having an ethylenically unsaturated group described later. It is preferable to obtain it by reacting with a compound. Through the above reaction, it becomes possible to introduce an ethylenically unsaturated group into the resin.

<Compounds having an ethylenically unsaturated group>

Examples of compounds having an ethylenically unsaturated group include isocyanate compounds, isothiocyanate compounds, epoxy compounds, aldehyde compounds, thioaldehyde compounds, ketone compounds, thioketone compounds, acetate compounds, carboxylic acid chlorides, carboxylic acid anhydrides, and carboxylic acid active esters. compounds, carboxylic acid compounds, alkyl halide compounds, alkyl azide compounds, triflate alkyl compounds, mesylate alkyl compounds, tosylate alkyl compounds, or alkyl cyanide compounds.

<Method for synthesizing polyimide, polybenzoxazole, polyimide precursor or polybenzoxazole precursor>

Polyimide, polyimide precursor, polybenzoxazole, or polybenzoxazole precursor can be synthesized by a known method. As a specific method, for example, diamines or bisaminophenol compounds are first dissolved in a reaction solvent, and a substantially equimolar amount of carboxylic acid anhydride is gradually added to this solution. Using a mechanical stirrer, the mixed solution is stirred at a temperature of preferably 0 to 200°C, more preferably 40 to 150°C, preferably for 0.5 to 50 hours, and more preferably for 2 to 24 hours. When using an end capping agent, after adding carboxylic acid anhydride and stirring at a predetermined temperature for a predetermined time, the end capping agent is gradually added and stirred.

The reaction solvent used in the polymerization reaction should be capable of dissolving the raw material diamines or bisaminophenol compounds and carboxylic acid anhydride, and is preferably a polar solvent. As a reaction solvent, for example, amides such as N,N-dimethylformamide, N,N-dimethylacetamide or N-methyl-2-pyrrolidone, γ-butyrolactone, γ-valerolactone, Cyclic esters such as δ-valerolactone, γ-caprolactone, ε-caprolactone or α-methyl-γ-butyrolactone, carbonates such as ethylene carbonate or propylene carbonate, triethylene glycol, etc. Examples include glycols, phenols such as m-cresol or p-cresol, or other solvents such as acetophenone, 1,3-dimethyl-2-imidazolidinone, sulfolane, and dimethyl sulfoxide. The amount of reaction solvent is preferably 100 to 1900 parts by mass, more preferably 150 to 950 parts by mass, when the total of diamines or bisaminophenol compounds and carboxylic acid anhydride is 100 parts by mass.

At least one type selected from polyimide, polybenzoxazole, polyimide precursor, and polybenzoxazole precursor is dissolved in methanol, water, etc. after the polymerization reaction is completed. It is preferable that it is obtained by precipitating one or more types selected from sol precursors in a poor solvent, followed by washing and drying. Since low molecular weight components, etc. can be removed by performing reprecipitation treatment, the mechanical properties of the cured film are significantly improved.

<Method for synthesizing polyimide containing ethylenically unsaturated group, polyimide precursor containing ethylenically unsaturated group, polybenzoxazole containing ethylenically unsaturated group, or polybenzoxazole precursor containing ethylenically unsaturated group>

The polyimide containing an ethylenically unsaturated group, the polyimide precursor containing an ethylenically unsaturated group, the polybenzoxazole containing an ethylenically unsaturated group, or the polybenzoxazole precursor containing an ethylenically unsaturated group can be synthesized by a known method.

Conditions for the reaction for introducing ethylenically unsaturated groups into polyimide, polybenzoxazole, polyimide precursor, or polybenzoxazole precursor include, for example, the inside of the reaction vessel under air or by bubbling or degassing under reduced pressure. After sufficient nitrogen substitution, polyimide, polyimide precursor, polybenzoxazole or polybenzoxazole precursor, and a compound having an ethylenically unsaturated group are added to the reaction solvent, and reacted at 20 to 110°C for 30 to 500 minutes. It is desirable. Additionally, if necessary, a polymerization inhibitor such as a phenol compound, an acid catalyst, or a base catalyst may be used.

In component (B), polyimide, polyimide precursor, polybenzoxazole, polybenzoxazole precursor, polyimide containing ethylenically unsaturated group, polyimide precursor containing ethylenically unsaturated group, polybenzoxa containing ethylenically unsaturated group. For specific description of the sol and polybenzoxazole precursor containing an ethylenically unsaturated group, the contents of [0074] to [0210] of International Publication No. 2017/159876 may be referred to.

The weight average molecular weight of component (B) is preferably 5,000 or more, more preferably 10,000 or more. Additionally, it is preferably 50,000 or less, and more preferably 40,000 or less. A weight average molecular weight of 5,000 or more is preferable because of high heat resistance. On the other hand, a weight average molecular weight of 50,000 or less is preferable from the viewpoint of solvent solubility.

The compounding amount of component (B) is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, with respect to 100 parts by mass of component (A), because good sensitivity is obtained and the desired pattern is obtained. Moreover, it is preferably 2,000 parts by mass or less, and more preferably 1,000 parts by mass or less.

· Ingredient (C)

Component (C) is a photosensitizer. The negative photosensitive resin composition of the present invention preferably contains as a photosensitive agent at least one selected from a photoacid generator, a photopolymerization initiator, and a radical polymerizable compound.

[Mine generator]

A photoacid generator refers to a compound that generates acid by causing bond cleavage upon exposure. By containing a photoacid generator, hardening of the exposed area is promoted and sensitivity can be improved. In addition, the photoacid generator that can improve the crosslinking density after thermal curing of the negative photosensitive resin composition and improve the chemical resistance of the cured film is not particularly limited, and known photoacid generators can be used. Examples include organic halogen compounds, sulfonic acid esters, onium salts, diazonium salts, and disulfone compounds.

Specific examples of photoacid generators include the following.

Tris(trichloromethyl)-s-triazine, tris(tribromomethyl)-s-triazine, tris(dibromomethyl)-s-triazine, 2,4-bis(tribromomethyl)- 6-p-methoxyphenyl-s-triazine, (2-[2-(5-methylfuran-2-yl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine), etc. haloalkyl group-containing s-triazine derivatives;

Halogen-substituted paraffinic hydrocarbon compounds such as 1,2,3,4-tetrabromobutane, 1,1,2,2-tetrabromoethane, carbon tetrabromide, and iodoform; Halogen-substituted cycloparaffinic hydrocarbon compounds such as hexabromocyclohexane, hexachlorocyclohexane, and hexabromocyclododecane;

benzene derivatives containing a haloalkyl group such as bis(trichloromethyl)benzene and bis(tribromomethyl)benzene; Sulfone compounds containing haloalkyl groups such as tribromomethylphenylsulfone and trichloromethylphenylsulfone; Halogen-containing sulfolane compounds such as 2,3-dibromosulfolane; isocyanurate compounds containing a haloalkyl group such as tris(2,3-dibromopropyl)isocyanurate;

Triphenylsulfonium chloride, diphenyl-4-methylphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium methanesulfonate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate, Sulfonium salts such as triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluoroarsenate, and triphenylsulfonium hexafluorophosphonate;

Diphenyliodonium trifluoromethanesulfonate, diphenyliodonium p-toluenesulfonate, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluoroarsenate, diphenyliodonium Iodonium salts such as hexafluorophosphonate;

Methyl p-toluenesulfonate, ethyl p-toluenesulfonate, butyl p-toluenesulfonate, phenyl p-toluenesulfonate, 1,2,3-tris(p-toluenesulfonyloxy)benzene, p-toluenesulfonate Benzoin ester, methyl methanesulfonate, ethyl methanesulfonate, butyl methanesulfonate, 1,2,3-tris(methanesulfonyloxy)benzene, phenyl methanesulfonate, benzoin methanesulfonate ester, trifluoromethane Methyl sulfonate, ethyl trifluoromethanesulfonate, butyl trifluoromethanesulfonate, 1,2,3-tris(trifluoromethanesulfonyloxy)benzene, phenyl trifluoromethanesulfonate, trifluoromethane Sulfonic acid ester compounds such as sulfonic acid benzoin ester; Disulfone compounds such as diphenyldisulfone;

Bis(phenylsulfonyl)diazomethane, bis(2,4-dimethylphenylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, cyclohexylsulfonyl-(2-methoxyphenylsulfonyl) Diazomethane, cyclohexylsulfonyl-(3-methoxyphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(4-methoxyphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(2-methoxy Phenylsulfonyl)diazomethane, cyclopentylsulfonyl-(3-methoxyphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(4-methoxyphenylsulfonyl)diazomethane, cyclohexylsulfonyl-( 2-Fluorophenylsulfonyl)diazomethane, cyclohexylsulfonyl-(3-fluorophenylsulfonyl)diazomethane, cyclohexylsulfonyl-(4-fluorophenylsulfonyl)diazomethane, cyclophene Tylsulfonyl-(2-fluorophenylsulfonyl)diazomethane, cyclopentylsulfonyl-(3-fluorophenylsulfonyl)diazomethane, cyclopentylsulfonyl-(4-fluorophenylsulfonyl)diazo Methane, cyclohexylsulfonyl-(2-chlorophenylsulfonyl)diazomethane, cyclohexylsulfonyl-(3-chlorophenylsulfonyl)diazomethane, cyclohexylsulfonyl-(4-chlorophenylsulfonyl)diazomethane Zomethane, cyclopentylsulfonyl-(2-chlorophenylsulfonyl)diazomethane, cyclopentylsulfonyl-(3-chlorophenylsulfonyl)diazomethane, cyclopentylsulfonyl-(4-chlorophenylsulfonyl) Diazomethane, cyclohexylsulfonyl-(2-trifluoromethylphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(3-trifluoromethylphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(4- Trifluoromethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(2-trifluoromethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(3-trifluoromethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(3-trifluoromethylphenylsulfonyl)diazomethane Pentylsulfonyl-(4-trifluoromethylphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(2-trifluoromethoxyphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(3-trifluoromethoxy) Phenylsulfonyl)diazomethane, cyclohexylsulfonyl-(4-trifluoromethoxyphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(2-trifluoromethoxyphenylsulfonyl)diazomethane, cyclophene Tylsulfonyl-(3-trifluoromethoxyphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(4-trifluoromethoxyphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(2,4,6- Trimethylphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(2,3,4-trimethylphenylsulfonyl)diazomethane, cyclohexylsulfonyl-(2,4,6-triethylphenylsulfonyl)diazo Methane, cyclohexylsulfonyl-(2,3,4-triethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(2,4,6-trimethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl- (2,3,4-trimethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(2,4,6-triethylphenylsulfonyl)diazomethane, cyclopentylsulfonyl-(2,3,4- Triethylphenylsulfonyl)diazomethane, phenylsulfonyl-(2-methoxyphenylsulfonyl)diazomethane, phenylsulfonyl-(3-methoxyphenylsulfonyl)diazomethane, phenylsulfonyl-(4 -Methoxyphenylsulfonyl)diazomethane, bis(2-methoxyphenylsulfonyl)diazomethane, bis(3-methoxyphenylsulfonyl)diazomethane, bis(4-methoxyphenylsulfonyl)diazomethane Zomethane, phenylsulfonyl-(2,4,6-trimethylphenylsulfonyl)diazomethane, phenylsulfonyl-(2,3,4-trimethylphenylsulfonyl)diazomethane, phenylsulfonyl-(2, 4,6-triethylphenylsulfonyl) diazomethane, phenylsulfonyl-(2,3,4-triethylphenylsulfonyl) diazomethane, 2,4-dimethylphenylsulfonyl-(2,4,6 -trimethylphenylsulfonyl)diazomethane, 2,4-dimethylphenylsulfonyl-(2,3,4-trimethylphenylsulfonyl)diazomethane, phenylsulfonyl-(2-fluorophenylsulfonyl)diazo Sulfone diazide compounds such as methane, phenylsulfonyl-(3-fluorophenylsulfonyl)diazomethane, and phenylsulfonyl-(4-fluorophenylsulfonyl)diazomethane;

o-nitrobenzyl ester compounds such as o-nitrobenzyl-p-toluenesulfonate;

Sulfone hydrazide compounds such as N,N'-di(phenylsulfonyl)hydrazide;

Sulfonium salts, which are salts of sulfonium cations such as triaryl sulfonium and trialalkyl sulfonium, and sulfonates such as fluoroalkane sulfonate, arenesulfonate, and alkanesulfonate;

iodonium salts that are salts of iodonium cations such as diaryliodonium and sulfonates such as fluoroalkane sulfonate, arenesulfonate, and alkanesulfonate;

Bis(alkylsulfonyl)diazomethane, bis(cycloalkylsulfonyl)diazomethane, bis(perfluoroalkylsulfonyl)diazomethane, bis(arylsulfonyl)diazomethane, bis(aralkylsulfonyl) Bissulfonyldiazomethane compounds such as diazomethane;

N-sulfonyloxyimide compounds consisting of a combination of dicarboxylic imide compounds and sulfonates such as fluoroalkane sulfonate, arenesulfonate, and alkane sulfonate;

Benzoin sulfonate compounds such as benzoin tosylate, benzoin mesylate, and benzoin butane sulfonate;

Polyhydroxyarene sulfonate compounds in which all of the hydroxy groups of the polyhydroxyarene compound are replaced with sulfonates such as fluoroalkane sulfonate, arenesulfonate, and alkane sulfonate;

Nitrobenzylsulfonate compounds such as (poly)nitrobenzyl fluoroalkanesulfonic acid, (poly)nitrobenzyl arenesulfonic acid, and (poly)nitrobenzyl alkanesulfonic acid;

Fluoroalkanebenzylsulfonate compounds such as (poly)fluoroalkanebenzyl fluoroalkanesulfonic acid, (poly)fluoroalkanebenzyl arenesulfonic acid, and (poly)fluoroalkanebenzyl alkanesulfonic acid;

Bis(arylsulfonyl)alkane compounds;

Bis-O-(arylsulfonyl)-α-dialkylglyoxime, bis-O-(arylsulfonyl)-α-dicycloalkylglyoxime, bis-O-(arylsulfonyl)-α-diarylgly Oxime, bis-O-(alkylsulfonyl)-α-dialkylglyoxime, bis-O-(alkylsulfonyl)-α-dicycloalkylglyoxime, bis-O-(alkylsulfonyl)-α-dia Lilglyoxime, bis-O-(fluoroalkylsulfonyl)-α-dialkylglyoxime, bis-O-(fluoroalkylsulfonyl)-α-dicycloalkylglyoxime, bis-O-(fluoro Alkylsulfonyl)-α-diarylglyoxime, bis-O-(arylsulfonyl)-α-dialkylnioxime, bis-O-(arylsulfonyl)-α-dicycloalkylnioxime, bis-O -(arylsulfonyl)-α-diarylnioxime, bis-O-(alkylsulfonyl)-α-dialkylnioxime, bis-O-(alkylsulfonyl)-α-dicycloalkylnioxime, bis- O-(alkylsulfonyl)-α-diarylnioxime, bis-O-(fluoroalkylsulfonyl)-α-dialkylnioxime, bis-O-(fluoroalkylsulfonyl)-α-dicycloalkyl oxime compounds such as nioxime and bis-O-(fluoroalkylsulfonyl)-α-diarylnioxime;

Arylsulfonyloxyiminoarylacetonitrile, Alkylsulfonyloxyiminoarylacetonitrile, Fluoroalkylsulfonyloxyiminoarylacetonitrile, ((arylsulfonyl)oxyimino-thiophene-ylidene)arylacetonitrile , ((alkylsulfonyl)oxyimino-thiophene-ylidene)arylacetonitrile, ((fluoroalkylsulfonyl)oxyimino-thiophene-ylidene)arylacetonitrile, bis(arylsulfonyloxyimino)aryl Lendiacetonitrile, bis(alkylsulfonyloxyimino)arylenediacetonitrile, bis(fluoroalkylsulfonyloxyimino)arylenediacetonitrile, arylfluoroalkanone-O-(alkylsulfonyl)oxime, Modified oxime compounds such as arylfluoroalkanone-O-(arylsulfonyl)oxime and arylfluoroalkanone-O-(fluoroalkylsulfonyl)oxime.

Photo acid generators may be used individually, or two or more types may be used in combination.

The compounding amount of the photoacid generator is preferably 0.1 parts by mass or more, more preferably 5 parts by mass or more, with respect to 100 parts by mass of component (A), because good sensitivity is obtained and the desired pattern is obtained. Moreover, it is preferably 20 parts by mass or less, and more preferably 15 parts by mass or less.

[Photopolymerization initiator]

A photopolymerization initiator refers to a compound that generates radicals by bond cleavage and/or reaction with exposure to light. By containing a photopolymerization initiator, the exposed portion of the film of the negative photosensitive resin composition becomes insoluble in the alkaline developer solution, making it possible to form a negative pattern. Additionally, hardening of the exposed area is promoted, and sensitivity can be improved.

The photopolymerization initiator is not particularly limited, and known photopolymerization initiators can be used. As a photopolymerization initiator, for example, a benzyl ketal-based photopolymerization initiator, an α-hydroxyketone-based photopolymerization initiator, an α-aminoketone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, an oxime ester-based photopolymerization initiator, and an acridine-based photopolymerization initiator. , a titanocene-based photopolymerization initiator, a benzophenone-based photopolymerization initiator, an acetophenone-based photopolymerization initiator, an aromatic keto ester-based photopolymerization initiator, or a benzoic acid ester-based photopolymerization initiator.

Photopolymerization initiators may be used individually by one type, or may be used in combination of two or more types.

The amount of the photopolymerization initiator mixed is preferably 0.1 parts by mass or more, more preferably 5 parts by mass or more, with respect to 100 parts by mass of component (A), because good sensitivity is obtained and the desired pattern is obtained. Moreover, it is preferably 20 parts by mass or less, and more preferably 15 parts by mass or less.

[Radical polymerizable compound]

A radically polymerizable compound refers to a compound having a plurality of ethylenically unsaturated groups in the molecule. By containing a radically polymerizable compound, hardening of the exposed area is promoted and sensitivity during exposure can be improved. Additionally, the crosslinking density after heat curing is improved, and the hardness of the cured film can be improved.

The radically polymerizable compound is not particularly limited, and known radically polymerizable compounds can be used, but a compound having a (meth)acrylic group in which radical polymerization easily progresses is preferable.

From the viewpoint of improving sensitivity during exposure and improving the hardness of the cured film, compounds having two or more (meth)acrylic groups in the molecule are more preferable.

As radically polymerizable compounds, for example, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethyl All-propane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane di(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tri(meth)acrylate ) Acrylate, ditrimethylolpropane tetra(meth)acrylate, 1,3-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1 ,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, dimethylol-tricyclodecane di(meth)acrylate , Ethoxylated glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ethoxylated pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tetra( Meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, tetra Pentaerythritol nona(meth)acrylate, tetrapentaerythritol deca(meth)acrylate, pentapentaerythritol undeca(meth)acrylate, pentapentaerythritol deca(meth)acrylate, ethoxylated bisphenol Adi. (meth)acrylate, 2,2-bis[4-(3-(meth)acryloxy-2-hydroxypropoxy)phenyl]propane, 1,3,5-tris((meth)acryloxyethyl)iso Cyanuric acid, 1,3-bis((meth)acryloxyethyl)isocyanuric acid, 9,9-bis[4-(2-(meth)acryloxyethoxy)phenyl]fluorene, 9,9- Bis[4-(3-(meth)acryloxypropoxy)phenyl]fluorene or 9,9-bis(4-(meth)acryloxyphenyl)fluorene or their acid modified products, ethylene oxide modified products or propylene oxide. Modified forms may be mentioned.

The amount of the radically polymerizable compound to be added is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, more preferably 1 part by mass or more, and especially 5 parts by mass or more, with respect to 100 parts by mass of component (A). desirable. If the content is within the above range, sensitivity during exposure can be improved. On the other hand, the content of the radically polymerizable compound is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and especially preferably 20 parts by mass or less.

The photosensitizer that is component (C) may be used individually, or may be used in combination of two or more types. For example, a photopolymerization initiator and a radically polymerizable compound may be blended simultaneously.

· Ingredient (D)

Solvents that are component (D) include polar aprotic solvents such as N-methyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide. Solvents, tetrahydrofuran, dioxane, ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, ethyl acetate, butyl acetate, isobutyl acetate, acetic acid. Ester such as propyl, propylene glycol monomethyl ether acetate, 3-methyl-3-methoxybutyl acetate, alcohol such as ethyl lactate, methyl lactate, diacetone alcohol, 3-methyl-3-methoxybutanol, toluene, Aromatic hydrocarbons, such as xylene, can be mentioned. These solvents may be used individually, or two or more types may be used in combination.

The compounding amount of component (D) in the negative photosensitive resin composition of the present embodiment is preferably such that the solid content concentration in the composition is such that a uniform coating film is obtained by applying a coating method such as spin coating to improve the fluidity of the composition. The amount is more than 5% by mass. Moreover, the amount is preferably 65% by mass or less.

· etc

In one embodiment, in addition to the above-mentioned components (A) to (D), various additives may be added to the negative photosensitive resin composition within a range that does not impair the effect of the present invention. Examples of additives include fillers, pigments, surfactants such as leveling agents, adhesion improvers, and dissolution accelerators.

In one embodiment, an organic base compound for neutralizing the acid generated from the photoacid generator (component (C)) during exposure may be included. When the negative photosensitive resin composition contains an organic base compound, the effect of preventing dimensional changes in the resist pattern due to movement of acid generated from the photoacid generator is obtained.

Specific examples of organic base compounds include pyrimidine, (poly)aminopyrimidine, (poly)hydroxypyrimidine, (poly)amino(poly)hydroxypyrimidine, (poly)amino(poly)alkylpyrimidine, (poly)aminopyrimidine, (poly)aminopyrimidine, and (poly)aminopyrimidine. ) Pyrimidine compounds such as amino (poly) alkoxypyrimidine, (poly) hydroxy (poly) alkyl pyrimidine, and (poly) hydroxy (poly) alkoxy pyrimidine; Pyridine compounds such as pyridine, (poly)alkylpyridine, and dialkylaminopyridine; amine compounds containing hydroxyalkyl groups such as polyalkanolamine, tri(hydroxyalkyl)aminoalkane, and bis(hydroxyalkyl)iminotris(hydroxyalkyl)alkane; Aminoaryl compounds such as aminophenol, etc. can be mentioned.

Organic base compounds may be used individually or in combination of two or more types.

The content of the organic base compound in the negative photosensitive resin composition is preferably 0.1 mol% or more, and more preferably 1 mol% or more, based on 1 mol of the photoacid generator. Additionally, it is preferably 100 mol% or less, and more preferably 50 mol% or less.

The negative photosensitive resin composition of this embodiment can be prepared by stirring and mixing the above-mentioned components (A) to (D) and various additives as needed by a usual method to obtain a uniform liquid.

When mixing solid substances such as fillers and pigments into the composition, it is preferable to disperse and mix them using a dispersing device such as a dissolver, homogenizer, or three roll mill. Additionally, the composition may be filtered using a mesh filter, membrane filter, etc. to remove particles or impurities.

[cured film/resist film]

The cured film according to one embodiment of the present invention is obtained by curing the negative photosensitive resin composition of the present invention described above.

Specifically, a film (photosensitive film) of the photosensitive resin composition from which the solvent has been removed is obtained by applying the negative photosensitive resin composition of the present invention onto an object to be photolithographed and prebaking it.

Application methods include spin coating, roll coating, flow coating, dip coating, spray coating, and doctor blade coating. Prebaking may be performed by heating, for example, at a temperature of 60°C or higher and 150°C or lower for a period of 30 seconds or more and 600 seconds or less.

By exposing the photosensitive film, the solubility of the exposed area in an alkaline developer is significantly reduced. Examples of light sources used for exposure include infrared light, visible light, ultraviolet light, far ultraviolet light, X-rays, and electron beams. Among these light sources, ultraviolet light is preferable, and the g-ray (wavelength 436 nm) and i-ray (wavelength 365 nm) of a high-pressure mercury lamp are suitable.

After exposure, heat treatment is performed at around 100°C to promote crosslinking reaction with component (A), component (B), and component (C) by catalytic reaction of acid generated by exposure.

Since the photosensitive film obtained from the negative photosensitive resin composition of the present invention has high alkali solubility, the difference in alkali solubility from the exposed portion is large, making high-resolution patterning possible. Therefore, it can be suitably used as a resist film.

Examples of the alkaline developer used for development after exposure include inorganic alkaline substances such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; Primary amines such as ethylamine and n-propylamine; Secondary amines such as diethylamine and di-n-butylamine; Tertiary amines such as triethylamine and methyldiethylamine; Alcohol amines such as dimethylethanolamine and triethanolamine; Quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide; and alkaline aqueous solutions of cyclic amines such as pyrrole and piperidine.

If necessary, alcohol, surfactant, etc. may be added to the alkaline developer. The alkali concentration of the alkaline developer is usually preferably in the range of 2 to 5% by mass, and a 2.38% by mass aqueous solution of tetramethylammonium hydroxide is generally used.

After development with an alkaline developer, a cured film in which the exposed portion is crosslinked is obtained by heating at a low temperature such as 150°C or higher and 200°C or lower, for example. The cured film of this embodiment is excellent in chemical resistance.

The cured film of this embodiment can be used, for example, for a pixel division layer in display devices such as an organic EL display.

[Example]

Hereinafter, the present invention will be described in more detail using specific examples. In addition, the weight average molecular weight (Mw) of the synthesized resin was measured under the following GPC measurement conditions.

[GPC measurement conditions]

Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation.

Column: Showa Denko Co., Ltd. “Shodex KF802”: 8.0mmΦ×300mm

+ Showa Denko Co., Ltd. “Shodex KF802”: 8.0mmΦ×300mm

+ Showa Denko Co., Ltd. “Shodex KF803”: 8.0mmΦ×300mm

+ Showa Denko Co., Ltd. “Shodex KF804”: 8.0mmΦ×300mm

Column temperature: 40℃

Detector: RI (differential refractometer)

Data processing: “GPC-8020 Model II version 4.30” manufactured by Tosoh Corporation.

Development solvent: tetrahydrofuran

Flow rate: 1.0mL/min

Sample: 0.5 mass% tetrahydrofuran solution in terms of resin solid content filtered through a microfilter.

Injection volume: 0.1mL

Standard sample: monodisperse polystyrene below

(Standard sample: monodisperse polystyrene)

“A-500” made by Tosoh Corporation

“A-2500” made by Tosoh Corporation

“A-5000” made by Tosoh Corporation

“F-1” made by Tosoh Corporation

“F-2” made by Tosoh Corporation

“F-4” made by Tosoh Corporation

“F-10” made by Tosoh Corporation

“F-20” made by Tosoh Kabushiki Kaisha.

[Ingredient (A)]

Synthesis Example 1 (Synthesis of novolak-type phenolic resin (A-1))

Into a four-necked flask with a capacity of 2000 mL equipped with a cooling tube, 164 g (1.52 mol) of m-cresol, 103 g (0.97 mol) of benzaldehyde, 74 g (0.61 mol) of salicylaldehyde, and 8 g of p-toluenesulfonic acid were added to the reaction solvent. It was dissolved in 300 g of ethanol. Afterwards, it was heated to 80°C with a mantle heater and stirred under reflux for 16 hours to cause reaction. After the reaction, ethyl acetate and water were added and the liquid was separated and washed five times. The solvent was distilled off under reduced pressure from the remaining resin solution, and then dried under vacuum to obtain 281 g of light red powder of novolak-type phenolic resin (A1).

The Mw of the novolak-type phenolic resin (A-1) was 3100. The GPC chart of novolak-type phenolic resin (A-1) is shown in Figure 1.

Synthesis Example 2 (Synthesis of novolak-type phenolic resin (A-2))

A novolak-type phenolic resin (A-2) was prepared in the same manner as in Synthesis Example 1, except that the starting raw materials were added to 164 g (1.52 mol) of m-cresol, 80 g (0.75 mol) of benzaldehyde, and 92 g (0.75 mol) of salicylaldehyde. ) 280g of powder was obtained. The Mw of the novolak-type phenolic resin (A-2) was 2370.

The GPC chart of novolak-type phenol resin (A-2) is shown in FIG. 2.

Synthesis Example 3 (Synthesis of novolak-type phenolic resin (A-3))

A novolak-type phenolic resin (A-3) was prepared in the same manner as in Synthesis Example 1, except that the starting raw materials were added to 164 g (1.52 mol) of m-cresol, 117 g (1.10 mol) of benzaldehyde, and 58 g (0.47 mol) of salicylaldehyde. ) 279g of powder was obtained. The Mw of the novolak-type phenol resin (A-3) was 2700.

The GPC chart of novolak-type phenolic resin (A-3) is shown in FIG. 3.

Synthesis Example 4 (Synthesis of novolak-type phenolic resin (A-4))

282 g of powder of novolak-type phenol resin (A5) was obtained in the same manner as in Synthesis Example 1, except that the reaction solvents were 250 g of ethanol, 30 g of 1-propanol, and 15 g of 2-propanol. The Mw of the novolak-type phenol resin (A-4) was 3200.

The GPC chart of novolak-type phenolic resin (A-4) is shown in Figure 5.

Comparative Synthesis Example 1 (Synthesis of novolak-type phenol resin (A-5))

Under a dry nitrogen stream, 70.29 g (0.65 mol) of m-cresol, 37.85 g (0.35 mol) of anisole as a reaction accelerator, and 0.62 g (0.005 mol) of oxalic acid dihydrate were added to a 2000 mL three-necked flask equipped with a cooling tube. After dissolving in 198.85 g of methyl isobutyl ketone (MIBK), 243.49 g of 37% by mass formaldehyde aqueous solution (3.00 mol of formaldehyde) was added, heated to 95°C with a mantle heater, and refluxed the reaction solution for 5 hours. The reaction was stirred. After that, the temperature was raised to 180°C, and water and MIBK were distilled out of the system. After that, the temperature was further raised to 195°C, and unreacted monomer was distilled off under reduced pressure of 150 torr (2.0 kPa). The obtained resin solid was once again dissolved in MIBK, water was added, and liquid separation and washing were performed 5 times. MIBK was distilled off under reduced pressure at 60°C using an evaporator, and then vacuum dried to obtain 212 g of novolak-type phenol resin (A-5) as a light red powder. The Mw of the novolak-type phenol resin (A-5) was 5500.

Comparative Synthesis Example 2 (Synthesis of novolak-type phenolic resin (A-6))

A novolak-type phenolic resin (A-6) was prepared in the same manner as in Synthesis Example 1, except that the starting raw materials were added to 164 g (1.52 mol) of m-cresol, 39 g (0.38 mol) of benzaldehyde, and 137 g (1.13 mol) of salicylaldehyde. ) 284g of powder was obtained. The Mw of the novolak-type phenolic resin (A-6) was 4700.

[Component (B)]

Synthesis Example 5 (Synthesis of polyimide precursor (B-1) containing ethylenically unsaturated group)

Under dry nitrogen airflow, 125 g (0.023 mol) of pyromellitic anhydride and 115 g (0.023 mol) of 4,4-diaminodiphenyl ether were added to N-methyl-2-pyrrolidone in a 2000 mL four-necked flask equipped with a cooling pipe. It was dissolved in 1602 g and stirred at 100°C for 4 hours to react. After completion of the reaction, the solution was added to 2000 g of water, and the polymer solid precipitate was collected by filtration. The polymer solid was dried in a vacuum dryer at 80°C for 72 hours to obtain polymer solid powder.

32.8 g of the obtained solid powder was dissolved in 76.5 g of 3-methoxy-n-butyl acetate. After cooling this mixed solution to 0°C, a solution of 3.2 g of 2-methacryloxyethyl isocyanate dissolved in 3.2 g of 3-methoxy-n-butylacetate was added dropwise. After completion of the dropwise addition, the mixture was stirred at 80°C for 1 hour to obtain a polymer solution containing an ethylenically unsaturated group. After completion of the reaction, the obtained solution was added to 1000 g of water, and the precipitate of the polymer solid containing an ethylenically unsaturated group was collected by filtration. The precipitate of polymer solid was collected by filtration. The ethylenically unsaturated group-containing polymer solid was dried in a vacuum dryer at 80°C for 72 hours to obtain polymer powder of the ethylenically unsaturated group-containing polyimide precursor (B-1).

[Negative photosensitive resin composition]

Example 1

As component (A), 4.2 g of phenol novolac resin (A-1) powder obtained in Synthesis Example 1, and as component (B), 1.8 g of polymer (B-1) powder of the ethylenically unsaturated group-containing polyimide precursor obtained in Synthesis Example 6. g, and as component (C), 4.0 g of radical polymerizable compound solution (dipentaerythritol hexaacrylate: manufactured by Nippon Kayaku Co., Ltd.) and 0.9 g of photopolymerization initiator solution (NCI-831: manufactured by ADEKA Co., Ltd.) was dissolved in 98 g of γ-butyrolactone, which is component (D), to obtain a negative photosensitive resin composition (F-1).

Examples 2 to 4, Comparative Examples 1 to 3

In Examples 2 to 4 and Comparative Examples 1 and 2, negative results were obtained in the same manner as in Example 1, except that the phenol novolak resin (A-2) to (A-6) powder shown in Table 1 was used as component (A). Photosensitive resin compositions (F-2) to (F-6) were obtained.

For Comparative Example 3, a negative photosensitive resin composition (F-7) was obtained in the same manner as in Example 1, except that the phenol novolac resin shown in Table 1 was not included as component (A).

[evaluation]

Using the negative photosensitive resin composition prepared in Examples and Comparative Examples, alkali solubility before exposure, chemical resistance of the cured film, and hardness of the cured film were evaluated.

(1) Evaluation of film forming properties (resin compatibility)

The negative photosensitive resin composition was applied to a silicon wafer with a diameter of 5 inches using a spin coater to a thickness of about 5 μm, and then prebaked at 120°C for 180 seconds to obtain a wafer with a photosensitive film formed thereon. The photosensitive film formed on the wafer surface was observed using an optical microscope to evaluate spattering and unevenness during film formation.

With respect to the photosensitive film, those without spattering or unevenness were considered to have good compatibility (○), and those with spattering or unevenness were designated as having poor compatibility (×). The evaluation results are shown in Table 1.

(2) Alkali solubility before exposure

The negative photosensitive resin composition was applied to a silicon wafer with a diameter of 5 inches using a spin coater to a thickness of about 5 μm, and then prebaked at 120°C for 180 seconds to obtain a wafer on which a photosensitive film (resist film) was formed. The wafer was immersed in a vat filled with 250 mL of developer (2.38% by weight aqueous solution of tetramethylammonium hydroxide (TMAH)) for 10 seconds. The wafer taken out of the vat was rinsed with pure water for 10 seconds, and the alkali solubility was evaluated by observing the residue of the photosensitive film on the wafer. A case with no residue at all was called extremely good (◎), a case with almost no residue was called good (○), and a case with a residue was called inadequate (×). The evaluation results are shown in Table 1.

(3) Chemical resistance of cured film

The negative photosensitive resin composition was applied to a silicon wafer with a diameter of 5 inches using a spin coater to a thickness of about 10 μm, and then prebaked at 120°C for 180 seconds to obtain a wafer with a photosensitive film formed thereon. Next, 200 mJ of ghi radiation was irradiated onto the photosensitive film using an Ushio multi-light. After irradiation, it was heated on a hot plate at 130°C for 120 seconds and further heated at 200°C for 1 hour in a nitrogen atmosphere to form a cured film.

After completion of heating, the wafer was taken out from a place where the temperature inside the heating device was 50°C or lower, and the film thickness was measured.

Afterwards, the wafer was divided into three parts, and each was immersed in acetone, N-methylpyrrolidone (NMP), and 2.38% by weight TMAH for 15 minutes. The wafer taken out of each solvent was washed with pure water, and then the film thickness was measured again.

Chemical resistance was evaluated based on the rate of change in film thickness before and after immersion in the solvent. A change rate of less than 2% was considered good (○), and a change rate of more than 2% was called inadequate (×). The evaluation results are shown in Table 1.

(4) Hardness of cured film

After obtaining the cured film as in (2) above, the wafer was taken out from a place where the temperature of the heating device was 50°C or lower, and the film thickness was measured. Membrane hardness was measured by the nanoindentation method (ENT-2100: manufactured by Erionix Co., Ltd.). Those with an indentation elastic modulus of 8 GPa or more were considered good (○), and those with an indentation elastic modulus of less than 8 GPa were considered inadequate (×). The evaluation results are shown in Table 1.

[Table 1]

In Table 1, the structural unit molar ratio "(a1)/(a2)/(a3)" of component (A) is: a structural unit derived from m-cresol (a1), a structural unit derived from benzaldehyde (a2), and the molar ratio of the structural unit (a3) derived from salicylaldehyde.

From the results in Table 1, it can be confirmed that the negative photosensitive resin composition of the present invention does not cause film forming defects and has excellent compatibility. Additionally, it can be confirmed that the resist film obtained from the negative photosensitive resin composition of the present invention has alkali solubility. In addition, it can be confirmed that the cured film has excellent chemical resistance and high hardness even though it is cured at a low temperature of 200°C.

Preparation Example 1 (Preparation of novolak-type phenolic resin (a-1))

The content of low-molecular-weight components with a weight average molecular weight of less than 500 in the novolak-type phenol resin (A-1) obtained in Synthesis Example 1 was evaluated by GPC, and the result was 3.9% by mass in terms of GPC area ratio.

200 g of this novolak-type phenol resin (A-1) was well dissolved in 300 g of methyl isobutyl ketone in a 2000 ml beaker, and then 300 g of heptane was added to precipitate the resin component. Low-molecular-weight components were removed by removing the supernatant. After repeating this operation three times, the resin component was recovered by dissolving the precipitated resin component in 300 g of methyl isobutyl ketone again, the solvent was distilled off under reduced pressure, and then vacuum dried to remove the low molecular weight component of the light red powder. Phenol 153 g of novolak resin powder (a-1) was obtained.

The weight average molecular weight (Mw) of the phenol novolak resin (a-1) was 2,750, and the content of low molecular weight components with a weight average molecular weight of less than 500 was 0.7% in terms of GPC area ratio. The GPC chart of phenol novolak resin (a-1) is shown in Figure 5.

Preparation Example 2 (Preparation of novolak-type phenolic resin (a-2))

The content of low-molecular-weight components with a weight average molecular weight of less than 500 in the novolak-type phenol resin (A-2) obtained in Synthesis Example 2 was evaluated by GPC, and the result was 3.7% by mass in terms of GPC area ratio.

This novolak-type phenol resin (A-2) was subjected to removal of low-molecular-weight components in the same manner as Preparation Example 1, and 156 g of phenol novolac resin powder (a-2) was obtained.

The weight average molecular weight (Mw) of the phenol novolac resin (a-2) was 2,840, and the content of low molecular weight components with a weight average molecular weight of less than 500 was 0.6% in terms of GPC area ratio.

Preparation Example 3 (Preparation of novolak-type phenolic resin (a-3))

The content of low-molecular-weight components with a weight average molecular weight of less than 500 in the novolak-type phenol resin (A-3) obtained in Synthesis Example 3 was evaluated by GPC, and the result was 3.2% by mass in terms of GPC area ratio.

This novolak-type phenol resin (A-3) was subjected to removal of low-molecular-weight components in the same manner as Preparation Example 1, and 151 g of phenol novolac resin powder (a-3) was obtained.

The weight average molecular weight (Mw) of the phenol novolac resin (a-3) was 3,130, and the content of low molecular weight components with a weight average molecular weight of less than 500 was 0.7% in terms of GPC area ratio.

Preparation Example 4 (Preparation of novolak-type phenolic resin (a-4))

The content of low-molecular-weight components with a weight average molecular weight of less than 500 in the novolak-type phenol resin (A-4) obtained in Synthesis Example 4 was evaluated by GPC, and the GPC area ratio was 4.1% by mass.

This novolak-type phenol resin (A-4) was subjected to removal of low-molecular-weight components in the same manner as Preparation Example 1, and 152 g of phenol novolak resin powder (a-4) was obtained.

The weight average molecular weight (Mw) of the phenol novolak resin (a-4) was 2,780, and the content of low molecular weight components with a weight average molecular weight of less than 500 was 0.8% in terms of GPC area ratio.

[Negative photosensitive resin composition]

Example 5

As component (A), 4.2 g of phenol novolac resin (a-1) powder obtained in Preparation Example 1, and as component (B), 1.8 g of polymer (B-1) powder of the ethylenically unsaturated group-containing polyimide precursor obtained in Synthesis Example 6. g, and as component (C), 4.0 g of radical polymerizable compound solution (dipentaerythritol hexaacrylate: manufactured by Nippon Kayaku Co., Ltd.) and 0.9 g of photopolymerization initiator solution (NCI-831: manufactured by ADEKA Co., Ltd.), By dissolving in 98 g of γ-butyrolactone, which is component (D), a negative photosensitive resin composition (f-1) was obtained.

Examples 6-8, Reference Examples 1-2

In Examples 6 to 8 and Reference Examples 1 and 2, phenol novolac resins (a-2) to (a-4), (A-1) and (A-6) shown in Table 2 were used as component (A). Negative photosensitive resin compositions (f-2) to (f-6) were obtained in the same manner as in Example 1, except that powder was used.

The obtained negative photosensitive resin composition was evaluated similarly to Examples 1 to 4 and Comparative Examples 1 to 3. The results are shown in Table 2.

[Table 2]

Claims (8)

A negative photosensitive resin composition containing the following components (A) to (D).
(A) Molar ratio of the structural unit derived from m-cresol (a1), the structural unit derived from benzaldehyde (a2), and the structural unit derived from salicylaldehyde (a3) [(a1):(a2):(a3) )] is 1.0:0.4~0.8:0.3~0.6 novolac type phenol resin
(B) one or more resins selected from polyimide containing an ethylenically unsaturated group, polyimide precursor containing an ethylenically unsaturated group, polybenzoxazole containing an ethylenically unsaturated group, and polybenzoxazole precursor containing an ethylenically unsaturated group
(C) Photosensitizer
(D) Solvent According to paragraph 1,
The component (A) is an acid catalyst in which m-cresol, benzaldehyde, and salicylaldehyde are mixed in an organic solvent in a molar ratio of m-cresol:benzaldehyde:salicylaldehyde = 1.0:0.4 to 0.8:0.3 to 0.6. A negative photosensitive resin composition, which is a novolak-type phenolic resin obtained by polycondensation. According to claim 1 or 2,
The total content of the structural unit (a1) derived from m-cresol, the structural unit (a2) derived from benzaldehyde, and the structural unit (a3) derived from salicylaldehyde in the component (A) is 30 mass. % or more of a negative photosensitive resin composition. According to any one of claims 1 to 3,
A negative photosensitive resin composition wherein the weight average molecular weight of the component (A) is 1,000 or more and 7,000 or less. According to any one of claims 1 to 4,
A negative photosensitive resin composition in which the component (A) having a molecular weight of less than 500 is less than 3.0% by mass in terms of area ratio as measured by gel permeation chromatography. According to any one of claims 1 to 5,
A negative photosensitive resin composition wherein the component (C) is at least one selected from a photoacid generator, a photopolymerization initiator, and a radically polymerizable compound. A cured film obtained from the negative photosensitive resin composition according to any one of claims 1 to 6. A resist film obtained from the negative photosensitive resin composition according to any one of claims 1 to 6.