TWI534539B - Negative type photosensitive resin composition - Google Patents

Description

Negative photosensitive resin composition

The present invention relates to a negative photosensitive resin composition and a cured film obtained therefrom. More specifically, the present invention relates to a photosensitive resin composition suitable for use in a display material, a cured film thereof, and various materials using the cured film.

It is known that an epoxy cationic polymerization-based UV curable resin containing an epoxy compound and a photoacid generator has high transparency and can increase the film thickness (for example, Patent Document 1). However, the coating film may be stuck before exposure after coating, and thus the handleability is poor. Further, since development cannot be carried out with an aqueous alkali solution, it is necessary to perform development by an organic solvent. Alkali development is considered to be carried out by introducing a carboxyl group into a polymer, and in the copolymerization of a monomer having an epoxy group and a monomer having a carboxyl group, an epoxy group easily reacts with a carboxyl group during polymerization. It is difficult to control the synthesis of the polymer. Further, even if the reaction can be controlled to synthesize a polymer, the storage stability is low.

As a substance capable of performing alkali development, a radical polymerization-based negative material containing a polymer having an acrylonitrile group, a polyfunctional acrylic monomer, and a photoradical initiator is known (for example, Patent Literature) 2). In the present invention, alkali imaging can be carried out by introducing a carboxyl group into a polymer. However, in order to increase the film thickness, it is necessary to increase the viscosity, and thus the handleability is poor. Since it is a radical type, there is a problem that it is easily blocked by oxygen on the surface during photohardening, and the film loss on the surface becomes large.

On the other hand, the positive type material has a high resolution, but it is difficult to increase the film thickness and the transparency is also low (for example, Patent Document 3).

From these points, it is desirable to have a material which has high transparency and can perform alkali development, even when the film thickness is increased, and the workability is high.

Further, it is also known to use maleic imine as an alkali-soluble resin (for example, Patent Document 4). In the present invention, it is proposed to use maleimide as the alkali-soluble group, however it is positive and cannot be used as a permanent film.

On the other hand, a certain negative photosensitive resin composition is known, which uses maleimide as an alkali-soluble resin (for example, Patent Document 5).

[Previous Technical Literature] [Patent Document]

Patent Document 1: International Patent Application Publication WO2008/007764

Patent Document 2: Japanese Laid-Open Patent Publication No. 2004-302389

Patent Document 3: Japanese Patent Laid-Open No. Hei 8-339082

Patent Document 4: Japanese Laid-Open Patent Publication No. 60-115932

Patent Document 5: Japanese Patent Laid-Open Publication No. 2010-15156

The present invention has been made in view of the above circumstances, and provides a negative photosensitive resin composition which can increase the film thickness even in a low-viscosity solution, and does not cause sticking before exposure, and can exhibit high resolution by alkali development. Forming the pattern, the finished film has high transparency and shrinkage after post-baking.

The inventors of the present invention have completed the present invention in order to solve the above problems and have conducted intensive studies.

In other words, the first aspect of the invention relates to a photosensitive resin composition comprising the following components (A), (B), (C), and (D): (A): at least An acrylic copolymer obtained by copolymerizing (i) a mixture of maleimide and (ii) a monomer having an epoxy group, (B) component: photoacid generator, and (C) component: 2 The above epoxy group compound and (D) component: solvent.

In the photosensitive resin composition of the first aspect, the sensitizer as the component (E) is further contained in an amount of 0.1 to 10 parts by mass based on 100 parts by mass of the photosensitive resin composition.

The photosensitive resin composition according to the first aspect or the second aspect, further comprising an amine compound as the component (F), which is 1% by mass or less based on the total mass of the photosensitive resin composition.

The fourth aspect is a cured film obtained by using the photosensitive resin composition as described in any one of the first aspect to the third aspect.

The fifth aspect is an interlayer insulating film for a liquid crystal display, which is composed of the cured film described in the fourth aspect.

The sixth viewpoint is an optical filter, which is recorded by the fourth viewpoint It consists of a cured film.

The photosensitive resin composition of the present invention can form a coating film pattern, and does not stick before exposure. Even if the film thickness is increased, the transparency and the resolution are still high, and the film shrinkage after post-baking is small, so it is most suitable. A structure as an optical member is formed.

The photosensitive resin composition of the present invention contains the photosensitive resin composition of the following (A) component, (B) component, (C) component, and (D) component.

(A) component: a monomer comprising at least (i) maleimide and (ii) an epoxy group-containing monomer, preferably a monomer mixture of an unsaturated double bond and a monomer having an epoxy group. Acrylic copolymer, component (B): photoacid generator, component (C): compound having two or more epoxy groups, and component (D): solvent

The details of each component are explained below.

<(A) component>

The component (A) is an acrylic copolymer obtained by copolymerizing at least a monomer mixture of (i) maleimine and (ii) a monomer having an epoxy group.

In the present invention, the copolymer refers to a polymer obtained by copolymerization using a monomer having an unsaturated double bond such as acrylate, methacrylate or styrene.

The copolymer of the component (A) is not particularly limited as long as it has a copolymer having such a structure, and the type of the polymer main chain skeleton and the side chain constituting the copolymer.

However, when the number average molecular weight of the acrylic copolymer of the component (A) exceeds 100,000 and is too large, the developability of the unexposed portion is lowered, and if the number average molecular weight is less than 2,000, the value is too small. Since the hardening of the exposed portion is insufficient, the component may be eluted at the time of development. Therefore, the number average molecular weight is in the range of 2,000 to 100,000.

(i) Maleic imine:

The maleidide used in the component (A) is limited to the structure represented by the formula (1).

(ii) a monomer having an epoxy group:

The monomer may be any monomer having an epoxy group, and is preferably an unsaturated double bond and a monomer having an epoxy group.

Examples of the unsaturated double bond and the monomer having an epoxy group include glycidyl methacrylate, glycidyl acrylate, 3,4-epoxycyclohexylmethyl methacrylate, and 3,4-epoxy acrylate. Hexylmethyl ester, allyl glycidyl ether, 3-vinyl-7-oxabicyclo[4.1.0]heptane, 1,2-epoxy-5-hexene, 1,7-octadiene monocyclic Oxide, etc.

Further, in the present invention, in the case of obtaining an acrylic copolymer having a specific functional group (epoxy group), a monomer which can be copolymerized with a monomer having a specific functional group and has a non-reactive functional group can be used in combination.

Specific examples of the monomer having a non-reactive functional group include an acrylate compound, a methacrylate compound, an N-substituted maleimide compound, acrylonitrile, maleic anhydride, a styrene compound, and a vinyl compound.

Specific examples of the above monomers are listed below, but are not limited thereto.

The acrylate compound may, for example, be methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, decyl acrylate, decyl methacrylate, phenyl acrylate, acrylic acid 2, 2, 2-three. Fluoroethyl ester, tributyl acrylate, cyclohexyl acrylate, isodecyl acrylate, 2-methoxyethyl acrylate, methoxy triethylene glycol acrylate, 2-ethoxyethyl acrylate, methyl Tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2,3-dihydroxypropyl acrylate, diethylene glycol monoacrylate, caprolactone 2-(acryloxy) Ethyl ester, poly(ethylene glycol) diethyl ether acrylate, 5-propenyloxy-6-hydroxynordecene- 2-carboxylic acid-6-lactone, acryloylethyl isocyanate, and 8-ethyl-8-tricyclodecyl acrylate.

Examples of the methacrylate compound include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, decyl methacrylate, and methacrylic acid. Mercaptomethyl ester, phenyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, isodecyl methacrylate, methacrylic acid 2-methoxyethyl ester, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofuran methyl methacrylate, 3-methoxybutyl methacrylate, A 2-methyl-2-adamantyl acrylate, γ-butyrolactone methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecylmethyl Acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2,3-dihydroxypropyl methacrylate, diethylene glycol monomethacrylate Ester, caprolactone 2-(methacryloxy)ethyl ester, poly(ethylene glycol) ethyl ether methacrylate, 5-methylpropenyloxy-6-hydroxynordecene- 2-carboxylic acid-6-lactone, methacryloylethyl isocyanate, and 8-ethyl-8-tricyclodecyl methacrylate.

Examples of the vinyl compound include methyl vinyl ether, benzyl vinyl ether, vinyl naphthalene, vinyl anthracene, vinyl biphenyl, vinyl carbazole, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, and C. Vinyl ether and the like.

Examples of the styrene compound include styrene, methyl styrene, chlorostyrene, and bromostyrene.

The aforementioned N-substituted maleimide compound may, for example, be an N-methyl horse. Indole, N-phenylmaleimide, and N-cyclohexylmaleimide.

The method for obtaining the acrylic copolymer having a specific functional group used in the present invention is not particularly limited, and may be, for example, a monomer having a specific functional group, and a non-reactive functional group having a copolymerizable non-reactive functional group. The polymer is obtained by carrying out a polymerization reaction at a temperature of 50 to 110 ° C in a solvent in which a polymerization initiator or the like is desired to coexist. In this case, the solvent to be used is not particularly limited as long as it is a monomer constituting an acrylic copolymer having a specific functional group and can dissolve an acrylic copolymer having a specific functional group. Specific examples thereof include the solvents described in the solvent (D) described later.

The acrylic copolymer having a specific functional group obtained in this manner is usually in a solution state dissolved in a solvent.

Further, the solution of the acrylic copolymer obtained as described above is poured into diethyl ether or water under stirring to reprecipitate, and the resulting precipitate is filtered and washed, and then subjected to normal temperature or reduced pressure at normal temperature. Or drying by heating, whereby a powder of an acrylic copolymer can be obtained. By this operation, the polymerization initiator or the unreacted monomer which coexists with the acrylic copolymer can be removed, and as a result, a powder of the purified acrylic copolymer can be obtained. In the case where the purification cannot be sufficiently performed in one operation, the obtained powder may be redissolved in a solvent and the above operation may be repeated.

In the present invention, the polymerization solution of the above acrylic copolymer may be used as it is, or the powder may be redissolved in a solvent such as (D) described later, and used as a solution.

Further, in the present invention, the acrylic copolymer of the component (A) may also be used. It is a mixture of a variety of specific copolymers.

The copolymerization ratio of the monomers is preferably maleic imine/epoxy/other; 10 to 60/10 to 40/0 to 80 parts by weight. In the case where the amount of the maleimide is too small, the unexposed portion is not dissolved in the developing solution, and it is likely to cause a residual film or residue. In the case of too many cases, the hardenability of the exposed portion is insufficient, and the pattern may not be formed. When the monomer having an epoxy group is too small, the photocurability is insufficient, and the exposed portion may be dissolved when it is developed. In an excessive case, the solubility of the unexposed portion is insufficient, which may cause a residual film or residue.

<(B) component>

The component (B) is a photoacid generator. The type of the acid used in the thermosetting resin composition of the present invention is not particularly limited. Specific examples of such a photoacid generator include:

The compound represented, diphenyl iodonium chloride, diphenyl iodonium trifluoromethane sulfonate, diphenyl iodonium methanesulfonate, diphenyl iodonium tosylate, diphenyl iodonium bromide, two Benziodonium tetrafluoroborate, diphenyliodonium hexafluoroantimonate, diphenyliodonium hexafluoroarsenate, bis(p-butylphenyl)iodonium hexafluorophosphate, double (pair Tributylphenyl)iodonium mesylate, bis(p-butylphenyl)iodonium tosylate, bis(p-butylphenyl)iodonium trifluoromethanesulfonate, double (p-tert-butylphenyl) iodonium tetrafluoroborate, bis(p-butylphenyl) iodonium chloride, bis(p-chlorophenyl) iodonium chloride, bis(p-chlorophenyl) Iodine tetrafluoroborate, triphenylsulfonium chloride, triphenylsulfonium bromide, triphenylsulfonium trifluoromethanesulfonate, tris(p-methoxyphenyl)phosphonium tetrafluoroborate, tris(p-methoxyl) Phenyl)phosphonium hexafluorophosphonate, tris(p-ethoxyphenyl)phosphonium tetrafluoroborate, triphenylsulfonium chloride, triphenylsulfonium bromide, tris(p-methoxyphenyl)phosphonium tetrafluoroborate Salt, tris(p-methoxyphenyl)phosphonium hexafluorophosphonate, tris(p-ethoxyphenyl)phosphonium tetrafluoroborate, and the like.

In the negative photosensitive resin composition of the present invention, the content of the component (B) is preferably 0.5 to 20 parts by mass, preferably 1 to 15 parts by mass, more preferably 100 parts by mass of the component (A). It is 2 to 10 parts by mass. When it is less than 0.5 part by mass, the photoreactivity may be lowered and the sensitivity may be lowered. In addition, when it exceeds 20 parts by mass, the formed coating film may have a decrease in transmittance and a decrease in storage stability of the solution.

<(C) component>

The epoxy compound having two or more epoxy groups as the component (C) of the present invention may, for example, be stilbene (2,3-epoxypropyl)isocyanurate or 1,4-butanediol diglycidyl. Ether, 1,2-epoxy-4-(epoxyethyl)cyclohexane, glycerol triglycidyl ether, diethylene glycol diglycidyl ether, 2,6-diglycidylphenyl glycidyl ether 1,1,3-glycol[p-(2,3-epoxypropoxy)phenyl]propane, 1,2-cyclohexanedicarboxylic acid diglycidyl ester, 4,4'-methylene Bis(N,N-diglycidylaniline), 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, trimethylolethane triglycidyl ether and bisphenol -A-diglycidyl ether, pentaerythritol polyglycidyl ether, and the like.

Further, a commercially available compound can also be used from the viewpoint of easy availability. The specific examples (trade names) are listed below, but they are not limited by these: YH-434, YH434L (made by Tohto Kasei Co., Ltd.), etc. Epoxy resin having an amine group: EPOLEAD GT-401 and the same series of GT-403, GT-301, GT-302, Celloxide 2021, Celloxide 3000 (manufactured by DAICEL Chemical Industry Co., Ltd.), etc. Epoxy resin: Epikote 1001 and the same series of 1002, 1003, 1004, 1007, 1009, 1010, 828 (above the oily shell Epoxy Co., Ltd. (now made by Japan Epoxy Resins Co., Ltd.)) Type epoxy resin; bisphenol F type epoxy resin such as Epikote 807 (oiled shell Epoxy Co., Ltd. (now made by Japan Epoxy Resins Co., Ltd.); Epikote 152 and the same series of 154 (above oily shell Epoxy) Phenol novolac type epoxy resin such as EOCN-102, EOCN-103S, EOCN, etc., EPPN201 and the same series of 202 (manufactured by Nippon Kayaku Co., Ltd.) -104S, EOCN-1020, EOCN-1025, EOCN-1027 (above is made by Nippon Kayaku Co., Ltd.), Epikote 180S75 (oiled shell Epoxy Co., Ltd. (now made by Japan Epoxy Resins Co., Ltd.)) Phenolic novolac type epoxy resin; De Nacol EX-252 (made by Nagasechemtex Co., Ltd.), CY175, CY177, CY179, ARALDITE CY-182 and the same series of CY-192, CY-184 (above, CLBA-GELGYA.G), Epiclon 200 and the same series 400 (above is made by Dainippon Ink Chemical Industry Co., Ltd.), Epikote 871 and the same series of 872 (above is Oiled Shell Epoxy Co., Ltd. (now made by Japan Epoxy Resins Co., Ltd.)), ED-5661, ED- 5662 (The above is a limited share of Celanese coating Epoxy resin such as company); Denacol EX-611 and the same series of EX-612, EX-614, EX-622, EX-411, EX-512, EX-522, EX-421, EX- 313, an aliphatic polyglycidyl ether such as EX-314 or EX-321 (manufactured by Nagasechemtex Co., Ltd.).

Further, a compound having at least two epoxy groups may also be a polymer having an epoxy group. Such a polymer can be used without particular limitation as long as it has an epoxy group and the N-unsubstituted maleimide is not contained in the repeating unit.

The polymer having the above epoxy group can be produced by addition polymerization using, for example, an addition polymerizable monomer having an epoxy group. Examples thereof include polyglycidyl acrylate, a copolymer of glycidyl methacrylate and ethyl methacrylate; glycidyl methacrylate, a copolymer of styrene and 2-hydroxyethyl methacrylate; Addition polymerized polymer; or polycondensed polymer such as epoxy phenolic.

Alternatively, the epoxy group-containing polymer may be produced by reacting a polymer compound having a hydroxyl group with an epoxy group-containing compound such as epichlorohydrin or glycidyl toluenesulfonate.

The weight average molecular weight of such a polymer is, for example, from 300 to 20,000.

These epoxy compounds having two or more epoxy groups may be used singly or in combination of two or more.

In the negative photosensitive resin composition of the present invention, the content of the epoxy compound having two or more epoxy groups in the component (C) is from 5 to 100% based on 100 parts by mass of the acrylic polymer of the component (A). It is preferably a component, preferably 10 to 80 parts by mass. In the case where the ratio is too small, there will be a negative type When the photocurability of the photosensitive resin composition is lowered, on the other hand, when the photoreceptor is too large, the developability of the unexposed portion may be lowered to cause a residual film or residue.

<(D) Solvent>

When the component (A) to the component (C) used in the present invention are dissolved, and the component (E) or the component (F) to be added which is added as desired may be dissolved, and the solvent having such a dissolving ability is used, The type and structure thereof are not particularly limited.

Examples of such a solvent (D) include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, and diethylene glycol. Alcohol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-butanone, 3 -methyl-2-pentanone, 2-pentanone, 2-heptanone, γ-butyrolactone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethoxyacetic acid Ethyl ester, hydroxyethyl acetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate , 3-ethoxypropionate methyl ester, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, and the like.

These solvents may be used alone or in combination of two or more.

Among these (D) solvents, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, and propylene glycol are preferred from the viewpoints of good coating film forming property and high safety. Methyl ether acetate, ethyl lactate, butyl lactate and the like are preferred. These solvents are generally used as a solvent for a photoresist material.

<(E) component>

The component (E) is a sensitizer. The coating film composed of the negative photosensitive resin composition of the present invention is exposed, and when the photoacid generator of the component (B) has a low reaction rate with respect to the wavelength to be exposed, the sensitizer can be added to enhance Reaction rate. Specific examples of such a sensitizer include 9,10-dibutoxy fluorene, 9-hydroxymethyl hydrazine, thioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, and 2 - chlorothioxanthone, 2,4-diethylthioxanthone, anthracene, 1,2-dihydroxyindole, 2-ethylanthracene, 1,4-diethoxynaphthalene, and the like.

The component (E) may be one or a combination of two or more of the above sensitizers.

The amount of the sensitizer added is usually 10 parts by mass or less, preferably 8 parts by mass or less, based on 100 parts by mass of the component (A). When 8 parts by mass or more is used, the transparency of the coating film may be lowered.

In addition, the amount of the sensitizer added is preferably 0.1 to 10 parts by mass based on 100 parts by mass of the photosensitive resin composition.

<(F) component>

The component (F) is an amine compound. In the negative photosensitive resin composition of the present invention, an amine compound can be added for the purpose of suppressing the diffusion of the acid generated by the component (B) to control the shape of the pattern.

The amine compound of the component (F) is not particularly limited, and a tertiary amine such as triethanolamine, triethylamine, tributylamine, triphenylamine, benzyldimethylamine or N-n-butyldiethanolamine is preferred.

The amine compound of the component (F) may be used alone or in combination of two or more.

In the case of using the amine compound, the content thereof is usually 1.0% by mass or less, preferably 0.5% by mass or less, based on 100% by mass of the negative photosensitive resin composition. When the amount of the amine compound used in the component (F) is more than 1.0% by mass, the sensitivity of the negative photosensitive resin composition may be greatly lowered.

<Other additives>

The negative photosensitive resin composition of the present invention may contain a surfactant, a rheology modifier, a pigment, a dye, a preservation stabilizer, an antifoaming agent, or a multivalent content as necessary even without impairing the effects of the present invention. A dissolution promoter such as a phenol or a polyvalent carboxylic acid.

<negative photosensitive resin composition>

The negative photosensitive resin composition of the present invention, wherein the acrylic polymer of the component (A), the photoacid generator of the component (B), and the compound having two or more epoxy groups of the component (C) are soluble ( D) A substance of a solvent, and one or more of the sensitizer of the component (E), the amine compound of the component (F), and other additives may be further contained as desired.

Among them, a suitable example of the negative photosensitive resin composition of the present invention is as follows As described below.

[1] A negative photosensitive resin composition containing (B) component and 5 to 100 parts by mass of (C) component based on 100 parts by mass of the component (A), and the component (C). The ingredients are dissolved in (D) solvent.

[2] A negative photosensitive resin composition further comprising the component (E) in the composition of the above [1], and 0.1 to 10 parts by mass based on 100 parts by mass of the component (A).

[3] A negative photosensitive resin composition further comprising the component (F) in the composition of the above [1] or [2], and 1 part by mass based on 100 parts by mass of the component (A). the following.

In the negative photosensitive resin composition of the present invention, the ratio of the solid component is not particularly limited as long as each component can be uniformly dissolved in the solvent, and is, for example, 1 to 80% by mass, and for example, 5 Up to 60% by mass, or 10 to 50% by mass. Here, the solid content refers to an object obtained by removing (D) a solvent from all components of the negative photosensitive resin composition.

The preparation method of the negative photosensitive resin composition of the present invention is not particularly limited, and the preparation method may be, for example, dissolving the component (A) (acrylic acid copolymer) in a solvent (D), and the solution is prepared in a predetermined ratio. a method in which a component (B) (photoacid generator) and a component (C) (a compound having two or more epoxy groups) are mixed to form a homogeneous solution, or may be further added as necessary in an appropriate stage of the preparation method. A method of mixing (E) a component (sensitizer), (F) component (amine compound), and other additives.

In the preparation of the negative photosensitive resin composition of the present invention, a solution of a specific copolymer obtained by a polymerization reaction in a solvent (D) may be used as it is, in which case, in the solution of the component (A) When a component (B) or a component (C) is added in the same manner as described above to form a homogeneous solution, the solvent (D) may be further added for the purpose of adjusting the concentration. At this time, the (D) solvent used in the formation of the specific copolymer may be the same as or different from the solvent (D) used for adjusting the concentration when the negative photosensitive resin composition is prepared.

Then, it is preferred that the solution of the negative photosensitive resin composition prepared is filtered through a filter having a pore diameter of about 0.2 μm or the like.

<Coating film and hardened film>

The negative photosensitive resin composition of the present invention is applied onto a semiconductor substrate by spin coating, flow coating, roll coating, slit coating, spin coating, spin coating, inkjet coating, or the like ( For example, a ruthenium/cerium oxide-coated substrate, a tantalum nitride substrate, a substrate coated with a metal such as aluminum, molybdenum or chromium, a glass substrate, a quartz substrate, an ITO substrate, or the like, and then pre-dried in a hot plate or an oven. Thereby, a coating film can be formed. Then, by performing heat treatment on the coating film, a negative photosensitive resin film can be formed.

For the heat treatment, for example, a heating temperature and a heating time which are appropriately selected from the range of a temperature of 70 ° C to 160 ° C and a time of 0.3 to 60 minutes can be employed. The heating temperature and heating time are preferably from 80 ° C to 140 ° C for 0.5 to 10 minutes.

In addition, negative photosensitiveness formed by a negative photosensitive resin composition The film thickness of the resin film is, for example, 0.1 to 30 μm, or for example, 0.5 to 20 μm, or even, for example, 1 to 15 μm.

When a negative photosensitive resin film formed of the negative photosensitive resin composition of the present invention is exposed to light having a predetermined pattern and exposed to light such as ultraviolet rays, ArF, KrF, or F ₂ laser light, The action of the acid generated by the photoacid generator (PAG) of the component (B) contained in the negative photosensitive resin film causes the exposed portion to be insoluble in the alkaline developing solution.

Next, post-exposure heating (PEB) is performed on the negative photosensitive resin film. In this case, the heating conditions may be appropriately selected heating temperatures and heating times from a temperature of 70 ° C to 150 ° C and a time of 0.3 to 60 minutes.

Then, development was performed using an alkaline developing solution. Thereby, a portion of the negative photosensitive resin film which is not exposed can be removed, and a three-dimensional shape can be formed.

Examples of the alkaline developing solution which can be used include an aqueous solution of an alkali metal hydroxide such as potassium hydroxide or sodium hydroxide, a tetrahydric hydroxide such as tetramethylammonium hydroxide, tetraethylammonium hydroxide or choline. An aqueous alkaline solution such as an aqueous ammonium solution, an aqueous amine solution such as ethanolamine, propylamine or ethylenediamine. Even a surfactant or the like can be added to these developing solutions.

In the above, the aqueous solution of tetraethylammonium hydroxide in an amount of 0.1 to 2.38 mass% is generally used as a developing solution for a photoresist, and the alkaline developing solution is also used in the photosensitive resin composition of the present invention, and does not cause A problem such as swelling can be well developed.

In addition, the development method can be carried out by a liquid-filling method, a dipping method, or a shaking impregnation method. Any of the others. The development time at this time is usually 15 to 180 seconds.

After development, the negative photosensitive resin film is washed with running water for, for example, 20 to 90 seconds, and then air-dried by using compressed air or compressed nitrogen or by spin centrifugation to remove moisture on the substrate, and then obtained A film having a pattern is formed.

Next, in order to perform heat hardening, post-baking is performed on the film on which the pattern is formed, and specifically, heating by using a hot plate, an oven, or the like, thereby obtaining excellent heat resistance, transparency, and flatness. A film having a good stereoscopic pattern, such as low water absorption, chemical resistance, and the like.

Regarding the post-baking method Generally, the heating temperature can be selected from a temperature range of 140 ° C to 250 ° C, in the case of a hot plate for 5 to 30 minutes, and in the case of an oven for 30 to 90 minutes.

Thus, by such post-baking, a cured film having a good pattern shape can be obtained.

As described above, the negative photosensitive resin composition of the present invention does not stick before exposure, and even if it is a film thickness of about 10 μm, a sufficiently high sensitivity can be formed, and at the time of development, the exposed portion is formed. A film with a very small film loss and a fine pattern. In addition, the shrinkage caused by post-baking is very small, and the in-plane distribution of the film thickness can be reduced even with a large substrate. Further, the cured film is excellent in transparency, heat resistance and solvent resistance. Therefore, it is suitable for various films used in liquid crystal displays, organic EL displays, touch panel elements, and the like, such as interlayer insulating films, protective films, insulating films, optical films, and the like.

[Examples]

The invention is further illustrated in the following examples, but the invention is not limited by the examples.

[abbreviation used in the embodiment]

The abbreviations used in the following examples are as follows.

MAA: Methacrylic acid

MI: Maleate

MMA: Methyl methacrylate

ECM: 3,4-epoxycyclohexylmethyl methacrylate

GMA: glycidyl methacrylate

ST: Styrene

AIBN: azobisisobutyronitrile

PAG1: GSID-26-1 (made by BASF)

PAG2: CPI-110P (manufactured by San Apro Co., Ltd.)

PAG3: HS-1PG (manufactured by San Apro Co., Ltd.)

PAG4: Irgacure 369 (made by BASF)

CEL: Celloxide P-2021 (product name) manufactured by DAICEL Chemical Co., Ltd. (Compound name: 3,4-epoxycyclohexenylmethyl-3', 4'-epoxycyclohexene carboxylate)

GT: DAICEL Chemical EPOLEAD GT-401 (product name) (Compound name, epoxidized butane tetracarboxylate-(3-cyclohexenylmethyl) modified ε-caprolactone)

ITX: 2-isopropyl thioxanthone

TEA: Triethanolamine

DPHA: dipentaerythritol penta/hexaacrylate

BTEAC: benzyl triethyl ammonium chloride

PGME: propylene glycol monomethyl ether

PGMEA: propylene glycol monomethyl ether acetate

JE: JER157S70 made by Japan Epoxy Resins Co., Ltd.

CHMI: N-cyclohexylmaleimide

[Determination of number average molecular weight and weight average molecular weight]

According to the following synthesis example, a GPC apparatus (Shodex (registered trademark) column KF803L and KF804L) manufactured by JASCO Corporation was used, and a solution of tetrahydrofuran was passed through a column (column temperature of 40 ° C) at a flow rate of 1 ml/min. The number average molecular weight and the weight average molecular weight of the obtained specific copolymer and the specific crosslinked body were measured under the conditions of elution. Further, the following number average molecular weight (hereinafter referred to as Mn) and weight average molecular weight (hereinafter referred to as Mw) are expressed in terms of polystyrene.

<Synthesis Example 1>

The monomer component constituting the copolymer was MI (28.0 g), ECM (50.0 g), ST (22.0 g), and the radical polymerization initiator was polymerized in AZ (2 g) to polymerize the solvent in PGME (238 g). The reaction was carried out to obtain (P1) a copolymer solution (copolymer concentration = 30% by mass) of Mn of 4,500 and Mw of 10,000. Further, the polymerization temperature was adjusted to 60 ° C to 90 ° C.

<Synthesis Example 2>

The monomer component constituting the copolymer was MI (30.0 g), GMA (50.0 g), ST (20.0 g), and the radical polymerization initiator was polymerized in AZ (2 g) to polymerize the solvent in PGME (238 g). The reaction was carried out to obtain a copolymer solution (copolymer concentration: 30% by mass) (P2) having Mn of 10,000 and Mw of 30,000. Further, the polymerization temperature was adjusted to 60 ° C to 90 ° C.

<Comparative Synthesis Example 1>

The monomer component constituting the copolymer was MAA (50.0 g) and MMA (50.0 g), and the radical polymerization initiator was AIBN (2 g), and the polymerization was carried out in the solvent PGMEA (120 g) to obtain copolymerization. Solution (copolymer concentration: 40% by mass). Further, the polymerization temperature was adjusted to 60 ° C to 90 ° C. GMA (33.0 g), BTEAC (1.1 g), and PGMEA (49.5 g) were added to and reacted with 200 g of the copolymer to obtain (A) component (specific copolymer) having Mn of 8,700 and Mw of 22,000. Solution (specific copolymer concentration: 40.5 mass%) (P3). Further, the reaction temperature was adjusted to 90 to 120 °C.

<Comparative Synthesis Example 2>

The monomer component constituting the copolymer is MAA (30.0 g), GMA (50.0 g), ST (20.0 g), and the radical polymerization initiator is AIBN (2 g), so that the solvent is in the solvent PGME (238 g). Temperature 60 ° C to 90 The polymerization was carried out at °C, however colloidalization occurred in the polymerization reaction and could not be used for subsequent evaluation.

<Comparative Synthesis Example 3>

The monomer components constituting the copolymer were CHMI (28.0 g), ECM (50.0 g), ST (22.0 g), and the radical polymerization initiator was polymerized in AZ (2 g) to polymerize the solvent in PGME (238 g). The reaction was carried out to obtain a copolymer solution (copolymer concentration: 30% by mass) (P4) having a Mn of 4,800 and a Mw of 12,000. Further, the polymerization temperature was adjusted to a temperature of from 60 ° C to 90 ° C.

<Examples 1 to 7 and Comparative Examples 1 to 4>

According to the composition shown in the following Table 1, the components (B), (C), and (D) are mixed in a predetermined ratio in the solution of the component (A), and further, the components (E) and (F) are further contained. The mixture was stirred at room temperature for 3 hours to prepare a homogeneous solution, whereby the negative photosensitive resin compositions of the respective examples and comparative examples were prepared.

The viscosity of each solution, the film thickness after prebaking, the transmittance, the resolution, and the residual film ratio were measured for each of the negative photosensitive resin compositions of Examples 1 to 7 and Comparative Examples 1 to 4.

[Evaluation of viscosity]

The viscosity of the negative photosensitive resin composition was measured using an E-type rotational viscometer (rotor No. 1 (1° 34') at a rotation speed of 10 rpm and a temperature of 25 ° C.

[Evaluation of film thickness after prebaking]

Coating a negative photosensitive resin composition on twin crystal using a spin coater After the circle was placed on a hot plate at a temperature of 100 ° C for 120 seconds, prebaking was carried out to form a coating film. The film thickness of this coating film was measured using F20 manufactured by FILMETRICS.

[Evaluation of Transmission Rate]

The negative photosensitive resin composition was applied onto a quartz substrate using a spin coater, and then placed on a hot plate at a temperature of 100 ° C for 120 seconds to be prebaked to form a coating film. The coating film was irradiated with ultraviolet rays for 36 seconds by a UV irradiation apparatus PLA-600FA manufactured by Canon, and the light intensity of ultraviolet rays at 365 nm was 5.5 mW/cm ² . The film was placed on a hot plate at a temperature of 95 ° C for 120 seconds to perform post-exposure heating, and then placed in an oven at a temperature of 230 ° C for 30 minutes to be post-baked to form a cured film. The transmittance of the wavelength of 400 nm was measured for this cured film using an ultraviolet-visible spectrophotometer (SIMADSU UV-2550 model manufactured by Shimadzu Corporation).

[Evaluation of resolution]

The negative photosensitive resin composition was applied onto an alkali-free glass using a spin coater, and then placed on a hot plate at a temperature of 100 ° C for 120 seconds to form a pre-baked coating film. The coating film was irradiated with ultraviolet rays at a line width and pitch of 190 mJ/cm ² by an ultraviolet irradiation apparatus PLA-600FA manufactured by Canon Co., Ltd., and the ultraviolet light had a light intensity of 5.5 mW/cm at a wavelength of 365 nm. ² . It was then placed on a hot plate at a temperature of 95 ° C for 120 seconds to perform post-exposure heating. Then, it was immersed in a 1.0% by mass aqueous solution of tetramethylammonium hydroxide (hereinafter referred to as TMAH) for 60 seconds, and then washed with ultrapure water for 20 seconds to form a pattern. The produced pattern was fired in an oven at 230 ° C for 30 minutes, and the obtained pattern was observed by SEM, and the minimum pattern size in which the pattern line width and the mask line width were matched was defined as the resolution.

[Evaluation of residual film rate]

The negative photosensitive resin composition was applied onto a tantalum wafer using a spin coater, and then placed on a hot plate at a temperature of 100 ° C for 120 seconds to be prebaked to form a coating film. The coating film was irradiated with ultraviolet rays for 36 seconds by a UV irradiation apparatus PLA-600FA manufactured by Canon, and the intensity of ultraviolet light at a wavelength of 365 nm was 5.5 mW/cm ² . The film was placed on a hot plate at a temperature of 95 ° C for 120 seconds to be heated after exposure, and then placed in an oven at a temperature of 230 ° C for 30 minutes to be post-baked to form a cured film. After post-baking, the film thickness was measured using F20 manufactured by FILMETRICS. The residual film ratio was calculated by (film thickness after post-baking/film thickness after prebaking) × 100.

[Results of the assessment]

The above evaluation results are disclosed in Table 2 below.

As is clear from the results shown in Table 2, any of the negative photosensitive resin compositions of Examples 1 to 7 can be coated even in the case of a thick film, although a low viscosity is maintained, and a high transmittance can be maintained even in a thick film. With resolution. Further, any of the residual film rates after post-baking is very high, and is 95% or more, that is, the shrinkage of the film is small.

In Comparative Example 1, even if the viscosity was the same, the film thickness could not be increased, and the residual film ratio after post-baking was as low as 90% or less. Regarding Comparative Example 2, sticking occurred after prebaking, and it was impossible to develop even using an alkali developing solution. Further, the negative photosensitive resin composition of Comparative Example 3 in which maleimide was N-substituted maleimide (cyclohexylmaleimide) was not developed in the alkali developing solution. Further, a photo-acid radical initiator Irgacure 369 was used instead of the photoacid generator of the component (B), and DPHA (dipentaerythritol penta/hexaacrylate) was used instead of the compound having two or more epoxy groups of the component (C). The negative photosensitive resin composition of Example 4 had a very large film loss at the time of development, and a good resolution could not be obtained.

[Industrial Availability]

The negative-type photosensitive resin composition obtained by the present invention is suitable as a protective film, a planarizing film, and an insulating film in various displays for forming a thin film transistor (TFT) liquid crystal display device, an organic EL device, and a touch panel device. The material of the cured film is particularly suitable as an interlayer insulating film for forming a TFT-type liquid crystal element, a protective film for a color filter, an array flattening film, an interlayer green film of a capacitive touch panel, and an organic EL element. A material such as an insulating film or a structural sheet which is an antireflection layer on the display surface.

Claims (6)

A photosensitive resin composition containing the following components (A), (B), (C), and (D): (A) component containing at least (i) formula (1) Acrylic copolymer obtained by copolymerization of maleimide with (ii) monomer mixture of epoxy group-containing monomer, component (B): photoacid generator, component (C): having two or more epoxy Base compound, (D) component: solvent; The photosensitive resin composition of the first aspect of the invention, which further contains the sensitizer as the component (E), and is 0.1 to 10 parts by mass based on 100 parts by mass of the photosensitive resin composition. The photosensitive resin composition of the first aspect of the invention, wherein the amine compound as the component (F) further contains 1% by mass or less based on the total mass of the photosensitive resin composition. A cured film obtained by using the photosensitive resin composition according to any one of claims 1 to 3. An interlayer insulating film for a liquid crystal display, which is composed of a cured film as disclosed in claim 4 of the patent application. An optical filter comprising a cured film as in item 4 of the patent application.