JP7368162B2 - Polymerizable unsaturated group-containing alkali-soluble resin, method for producing the same, photosensitive resin composition, and cured film thereof. - Google Patents

Description

The present invention relates to a method for producing an alkali-soluble resin containing a polymerizable unsaturated group, an alkali-soluble resin containing a polymerizable unsaturated group, a photosensitive resin composition containing the same as an essential component, and a cured film obtained by curing the same. The photosensitive resin composition containing the specific polymerizable unsaturated group-containing alkali-soluble resin of the present invention and its cured product can be used for resist layers such as solder resist layers, plating resist layers, etching resist layers, and interlayers such as multilayer printed wiring boards. It can be applied as an insulating layer, gas barrier film, encapsulant for lenses and semiconductor light emitting devices such as light emitting diodes (LEDs), top coat for paints and inks, hard coat for plastics, anti-corrosion film for metals, etc. be.

2. Description of the Related Art As electronic devices, display members, etc. have become more sophisticated and sophisticated in recent years, the electronic components used therein are required to be smaller and more dense. Further, in terms of the workability of the insulating materials used in these materials, there is a growing demand for miniaturization and optimization of the cross-sectional shape of the processed patterns. A method of patterning by exposure and development is known as an effective means for microfabrication of insulating materials, and photosensitive resin compositions have been used for this, but improvements in sensitivity, adhesion to substrates, reliability, Many properties such as heat resistance and chemical resistance are now required. In addition, various studies have been conducted on the use of organic insulating materials in the gate insulating film for organic TFTs, but there is a need to reduce the operating voltage of organic TFTs by making the gate insulating film thinner, and the dielectric breakdown voltage is generally low. For organic insulating materials, which have a voltage of about 1 MV/cm, the voltage is about 0.
Application of a thin film of about 2 μm is being considered.

Conventional insulating materials made of photosensitive resin compositions utilize a photocuring reaction resulting from the reaction between a photoreactive alkali-soluble resin and a photopolymerization initiator, and mercury lamps are mainly used as the exposure wavelength for photocuring. The i-line (365 nm), which is one of the line spectra, is used. However, this i-line is absorbed by the photosensitive resin itself and the colorant, resulting in a decrease in the degree of photocuring. Moreover, if the film is thick, the amount of absorption increases. Therefore, a difference in crosslink density in the film thickness direction occurs in the exposed area, and even if the surface of the coating film is sufficiently photocured, it is difficult to photocure at the bottom of the coating film, resulting in a difference in crosslink density between the exposed area and the unexposed area. It became extremely difficult to attach a photosensitive insulating material that could be developed with high resolution, and the pattern dimensional stability, development margin, pattern adhesion, edge shape and cross-sectional shape of the pattern deteriorated, and it was difficult to obtain a photosensitive insulating material that could be developed with high resolution.

Generally, photosensitive resin compositions used in such applications contain polyfunctional photocurable monomers with polymerizable unsaturated bonds, alkali-soluble binder resins, photopolymerization initiators, etc. , photosensitive resin compositions that have been technically disclosed for application as materials for color filters can be applied. For example, Patent Document 1 and Patent Document 2 disclose copolymers of (meth)acrylic acid or (meth)acrylic acid ester having a carboxyl group as a binder resin, maleic anhydride, and other polymerizable monomers. has been done. Further, Patent Document 3 discloses that an alkali-soluble unsaturated compound having a polymerizable unsaturated double bond and a carboxyl group in one molecule is effective for forming negative patterns such as color filters. .

On the other hand, Patent Document 4, Patent Document 5, Patent Document 6, and Patent Document 7 disclose liquid resins using a reaction product of an epoxy (meth)acrylate having a bisphenol fluorene structure and an acid anhydride.

Japanese Patent Application Publication No. 61-213213 Japanese Patent Application Publication No. 1-152449 Japanese Patent Application Publication No. 4-340965 Japanese Patent Application Publication No. 4-345673 Japanese Patent Application Publication No. 4-345608 Japanese Patent Application Publication No. 4-355450 Japanese Patent Application Publication No. 4-363311

However, since the copolymers disclosed in Patent Document 1 and Patent Document 2 are random copolymers, a distribution of alkali dissolution rates occurs in the light-irradiated area and the non-light-irradiated area, and the development process The time margin is narrow, making it difficult to obtain sharp pattern shapes or fine patterns. In particular, when a high concentration of pigment is included, the exposure sensitivity is significantly reduced, making it impossible to obtain a fine negative pattern.

Furthermore, since the alkali-soluble unsaturated compound described in Patent Document 3 becomes insolubilized by light irradiation, it is predicted that the sensitivity will be higher than that of the combination of the binder resin and the polyfunctional polymerizable monomer described above. However, the compound exemplified here is one in which acrylic acid and acid anhydride, which are polymerizable unsaturated groups, are optionally added to the hydroxyl group of a phenol oligomer, and even in the case of such a proposal, each molecule is Since there is a wide distribution in the molecular weight and the amount of carboxyl groups, the alkali dissolution rate of the alkali-soluble resin has a wide distribution, making it difficult to form a fine negative pattern.

Furthermore, the resins exemplified in Patent Documents 4, 5, 6, and 7 have small molecular weights because they are reaction products of epoxy (meth)acrylate and acid anhydride. Therefore, it is difficult to increase the difference in alkali solubility between the exposed area and the unexposed area, making it impossible to form a fine pattern.

In this way, photolithography methods using various photosensitive resin compositions are used as a microfabrication method for insulating materials, but once the pattern has been made finer and the shape has been optimized, it is possible to However, various properties such as adhesion to substrates, reliability, heat resistance, and chemical resistance are now required. For example, when used in flexible displays and touch panels, there may be cases where resistance to folding is required, and we also need to provide materials with excellent chemical resistance, which is required in electrode processing processes after insulating film formation. has become necessary.

An object of the present invention is to provide a photosensitive resin composition that can be patterned with excellent resolution by alkaline development, and that can be applied to insulating films, etc., which also has excellent reliability such as resistance to folding. be. Other objects are a method for producing an alkali-soluble resin containing a polymerizable unsaturated group to be used in this photosensitive resin composition, an alkali-soluble resin containing a polymerizable unsaturated group produced by this production method, and a photosensitive resin. An object of the present invention is to provide a cured film obtained by curing a composition.

In order to solve the above problems, the present inventors discovered that it is effective to use a photosensitive resin composition using an alkali-soluble resin containing a polymerizable unsaturated group having a specific alicyclic structure, and the present invention Completed the invention.

The present invention provides an epoxy (meth)acrylate resin represented by the following general formula (1) with (a) a dicarboxylic acid, a tricarboxylic acid, or an acid anhydride thereof, and (b) a tetracarboxylic acid or its acid dicarboxylic acid. The present invention relates to a method for producing an alkali-soluble resin containing a polymerizable unsaturated group, which is characterized by reacting an anhydride.

式中、Ｒ^１は炭素数１～８のアルキル基、フェニル基又はアリル基を示し、Ｒ^２は水素原子又はメチル基を示す。

In the formula, R ¹ represents an alkyl group having 1 to 8 carbon atoms, a phenyl group or an allyl group, and R ² represents a hydrogen atom or a methyl group.

Further, another embodiment of the present invention is an alkali-soluble resin containing a polymerizable unsaturated group obtained by the above production method, the alkali-soluble resin containing a polymerizable unsaturated group having a structure represented by general formula (2). Regarding resin.

式中、Ｒ^２は水素原子又はメチル基を示し、Ｘは４価のカルボン酸残基を示し、Ｙは上記式（３）で表される置換基又は水素原子を示し、Ｚは上記式（２ａ）で表される構造を示し、ｍは平均値が１～２０の数である。
式（２ａ）中、Ｒ^１は炭素数１～８のアルキル基、フェニル基又はアリル基を示す。
式（３）中、Ｍはｐ＋１価のカルボン酸残基を示し、ｐは１又は２である。

In the formula, R ² represents a hydrogen atom or a methyl group, X represents a tetravalent carboxylic acid residue, Y represents a substituent represented by the above formula (3) or a hydrogen atom, and Z represents the above formula ( 2a), where m is a number with an average value of 1 to 20.
In formula (2a), R ¹ represents an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group.
In formula (3), M represents a p+1-valent carboxylic acid residue, and p is 1 or 2.

Further, other embodiments of the present invention include:
(A) the above polymerizable unsaturated group-containing alkali-soluble resin;
(B) a photopolymerizable monomer having at least two polymerizable unsaturated groups;
The present invention relates to a photosensitive resin composition containing (C) a photopolymerization initiator and (D) a solvent as essential components.

Further, another embodiment of the present invention relates to a cured product obtained by curing the photosensitive resin composition.

The photosensitive resin composition of the present invention using the polymerizable unsaturated group-containing alkali-soluble resin having a specific alicyclic structure can be patterned by alkaline development, and the cured product has a low elastic modulus and excellent folding properties. It can be used as an insulating film for flexible displays and touch panels. Moreover, when it is necessary to undergo a processing process such as electrode formation after forming an insulating film in a touch panel manufacturing process or the like, a cured product pattern having excellent chemical resistance can be obtained.

The present invention will be explained in detail below.
One embodiment of the present invention provides an epoxy (meth)acrylate resin represented by general formula (1) with (a) dicarboxylic acid, tricarboxylic acid, or an acid anhydride thereof, and (b) tetracarboxylic acid or The present invention relates to a method for producing an alkali-soluble resin containing a polymerizable unsaturated group by reacting the acid dianhydride, and an alkali-soluble resin containing a polymerizable unsaturated group produced by the method.

The raw material for the epoxy (meth)acrylate resin is obtained by a reaction between a dicyclopentadiene type epoxy resin and (meth)acrylic acid (acrylic acid, methacrylic acid, or both). This epoxy resin can be obtained by reacting a diphenol compound represented by the following general formula (4) with an epihalohydrin such as epichlorohydrin to epoxidize it. This diphenol compound can be obtained by reacting a 2,6-disubstituted phenol compound and dicyclopentadiene in the presence of a catalyst such as a boron trifluoride/ether complex.

式中、Ｒ^１は一般式（１）のＲ^１と同義である。

In the formula, R ¹ has the same meaning as R ¹ in general formula (1).

The above diphenol compound is prepared by adding preferably 0.1 to 0.2 mol, more preferably 0.1 to 0.15 mol of dicyclopentadiene to 1 mol of the 2,6-disubstituted phenol compound, and adding dicyclopentadiene to 1 mol of the 2,6-disubstituted phenol compound. It can be obtained by reacting in the presence of

Examples of the 2,6-disubstituted phenol compounds include 2,6-dimethylphenol, 2,6-diethylphenol, 2,6-dipropylphenol, 2,6-diisopropylphenol, 2,6-di(n-butylphenol), and 2,6-di(n-butylphenol). ) Phenol, 2,6-di(t-butyl)phenol, 2,6-dihexylphenol, 2,6-dicyclohexylphenol, 2,6-diphenylphenol, etc., but they are easy to obtain and cured. From the viewpoint of reactivity, 2,6-dimethylphenol is preferred.

The acid catalyst used when reacting phenols with dicyclopentadiene is a Lewis acid, and specifically, trifluoride such as boron trifluoride, boron trifluoride/phenol complex, boron trifluoride/ether complex, etc. These include boron fluoride compounds, metal chlorides such as aluminum chloride, tin chloride, zinc chloride, titanium tetrachloride, and iron chloride, and organic sulfonic acids such as methanesulfonic acid, ethanesulfonic acid, and propanesulfonic acid. Boron trifluoride/ether complex is preferred from the viewpoint of ease of handling. The amount of the acid catalyst used is 0.001 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of dicyclopentadiene in the case of the boron trifluoride/ether complex.

A preferred reaction method is to charge 2,6-disubstituted phenol and a catalyst into a reactor, and drop dicyclopentadiene over 1 to 10 hours.
The reaction temperature is 50 to 200°C, and the reaction time is 1 to 10 hours.

After the reaction is completed, an alkali such as sodium hydroxide or potassium hydroxide is added to deactivate the catalyst, and unreacted 2,6-disubstituted phenol is recovered under reduced pressure.

After that, in order to separate and purify the reaction product, a solvent such as toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, etc. is added and dissolved, and after washing with water, the solvent and unreacted raw materials are recovered under reduced pressure. A diphenol compound can be obtained.

In addition, during the reaction, a solvent such as benzene, toluene, xylene, chlorobenzene, dichlorobenzene, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc. may be used as necessary for viscosity adjustment and the like.

A dicyclopentadiene type epoxy resin is obtained by reacting the diphenol compound obtained by the above method with epihalohydrin. This reaction is carried out according to conventionally known methods.

For example, an alkali metal hydroxide such as sodium hydroxide is added as a solid or concentrated aqueous solution to a mixture of a diphenol compound and epihalohydrin in an excess molar amount relative to the hydroxyl group of the diphenol compound, and the reaction temperature is 30 to 120°C. It can be obtained by reacting for 0.5 to 10 hours, or by adding a quaternary ammonium salt such as tetraethylammonium chloride to a diphenol compound and an excess molar amount of epihalohydrin as a catalyst, and reacting at a temperature of 50 to 150°C for 1 to 5 hours. It can be obtained by adding an alkali metal hydroxide such as sodium hydroxide to polyhalohydrin ether as a solid or concentrated aqueous solution and reacting at a temperature of 30 to 120°C for 1 to 10 hours.

In the above reaction, the amount of epihalohydrin used is 1 to 10 times the mole of the hydroxyl group of the diphenol compound, preferably 2 to 5 times the mole, and the amount of alkali metal hydroxide used is the amount of the hydroxyl group of the diphenol compound. The amount is in the range of 0.85 to 1.1 moles relative to the hydroxyl group.

Since the epoxy resin obtained by these reactions contains unreacted epihalohydrin and alkali metal halide, the unreacted epihalohydrin is removed by evaporation from the reaction mixture, and the alkali metal halide is further extracted with water. The desired epoxy resin can be obtained by removing the resin by a method such as filtration or separation. The epoxy resin thus obtained is a dicyclopentadiene type epoxy resin and is represented by the following general formula (5).

式中、Ｒ^１は一般式（１）のＲ^１と同義であり、ｎは平均値で０～５の数を示す。

In the formula, R ¹ has the same meaning as R ¹ in general formula (1), and n represents a number from 0 to 5 as an average value.

The epoxy equivalent (g/eq.) of the epoxy resin is preferably from 244 to 3,700, more preferably from 260 to 2,000, and even more preferably from more than 270 to less than 700.

The molecular weight distribution of the obtained epoxy resin can be changed by changing the charging ratio of the diphenol compound and epihalohydrin during the epoxidation reaction, and the amount of epihalohydrin used can be made close to equimolar to the hydroxyl group of the diphenol compound. The closer the molecular weight is to 20 times the molar ratio, the lower the molecular weight distribution becomes. Furthermore, it is also possible to increase the molecular weight of the obtained epoxy resin by allowing the diphenol compound to act on it again.
However, in order to appropriately control the molecular weight of the polymerizable unsaturated group-containing alkali-soluble resin of the present invention, in general formula (5), the content of n = 0 is preferably 50% or more, and 70 % or more, more preferably 85% or more, and particularly preferably 95% or more. Further, n is within the range of 0 to 5 on average, preferably within the range of 0 to 2, more preferably within the range of 0 to 1, and within the range of 0 to 0.5. It is particularly preferable that there be. Within this range, excessive molecular weight increase due to addition of acid dianhydride can be easily suppressed.

The above epoxy resin is reacted with (meth)acrylic acid to form an epoxy (meth)acrylate resin having a polymerizable unsaturated group.
The epoxy resin and (meth)acrylic acid can be reacted by a known method. For example, an equimolar amount of (meth)acrylic acid is used per mole of epoxy groups in the above epoxy resin, but in order to react with (meth)acrylic acid to all the epoxy groups, the epoxy group and carxyl group are equivalent in mole. (Meth)acrylic acid may also be used in slight excess. This reaction yields an epoxy (meth)acrylate resin in which the glycidyl group in general formula (5) is substituted with a group represented by formula (6) below.

式中、Ｒ^２は一般式（１）のＲ^２と同義である。

In the formula, R ² has the same meaning as R ² in general formula (1).

The solvent and catalyst used in this reaction and other reaction conditions are not particularly limited. For example, as the solvent, it is preferable to use a solvent that does not have a hydroxyl group and has a boiling point higher than the reaction temperature. Examples of such solvents include cellosolve solvents such as ethyl cellosolve acetate and butyl cellosolve acetate, high boiling point ether or ester solvents such as diglyme, ethyl carbitol acetate, butyl carbitol acetate, and propylene glycol monomethyl ether acetate. Furthermore, there are ketone solvents such as cyclohexanone and diisobutyl ketone.
Examples of the above-mentioned catalysts include known catalysts such as ammonium salts including tetraethylammonium bromide and triethylbenzylammonium chloride, and phosphines such as triphenylphosphine and tris(2,6-dimethoxyphenyl)phosphine.

Through this reaction, an epoxy (meth)acrylate resin represented by general formula (1) is obtained. This epoxy (meth)acrylate resin contains by-products derived from side reactions and by-products derived from by-products included during the synthesis of raw materials, but these may be purified and removed before use. As long as it does not affect the quality or use of the product, it may be used with some of the by-products remaining.

An alkali-soluble resin containing a polymerizable unsaturated group can be obtained by reacting the epoxy (meth)acrylate resin with carboxylic acids.
As the carboxylic acids, (a) dicarboxylic acids or tricarboxylic acids and (b) tetracarboxylic acids are used. The dicarboxylic acids or tricarboxylic acids may be dicarboxylic acids or tricarboxylic acids, or acid anhydrides thereof, but acid anhydrides are suitable in terms of reactivity. Similarly, the tetracarboxylic acids may be tetracarboxylic acids or acid dianhydrides thereof, but acid dianhydrides are suitable in terms of reactivity.

Examples of (a) dicarboxylic acids, tricarboxylic acids, or their acid anhydrides include saturated chain hydrocarbon dicarboxylic acids, tricarboxylic acids, or their acid anhydrides, saturated cyclic hydrocarbon dicarboxylic acids, tricarboxylic acids, or their acid anhydrides. Included are acid anhydrides, unsaturated hydrocarbon dicarboxylic acids, tricarboxylic acids, or their acid anhydrides, aromatic hydrocarbon dicarboxylic acids, tricarboxylic acids, and their acid anhydrides. In addition, each hydrocarbon residue (structure excluding a carboxyl group) of these dicarboxylic acids, tricarboxylic acids, or these acid anhydrides is further substituted with a substituent such as an alkyl group, a cycloalkyl group, or an aromatic group. It's okay.

Examples of saturated chain hydrocarbon dicarboxylic or tricarboxylic acids include succinic acid, acetylsuccinic acid, adipic acid, azelaic acid, citramalic acid, malonic acid, glutaric acid, citric acid, tartaric acid, oxoglutaric acid, pimelic acid, sebacic acid. , suberic acid, and diglycolic acid. Examples of saturated cyclic hydrocarbon dicarboxylic or tricarboxylic acids include hexahydrophthalic acid, cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, norbornanedicarboxylic acid, hexahydrotrimellitic acid, and the like. Examples of unsaturated dicarboxylic or tricarboxylic acids include maleic acid, itaconic acid, tetrahydrophthalic acid, methylendomethylenetetrahydrophthalic acid, chlorendic acid, and the like. Examples of aromatic hydrocarbon dicarboxylic acids or tricarboxylic acids include phthalic acid, trimellitic acid, and the like. Acid anhydrides of these dicarboxylic or tricarboxylic acid compounds can also be used. Among these, succinic acid, itaconic acid, tetrahydrophthalic acid, hexahydrotrimellitic acid, phthalic acid, trimellitic acid, or anhydrides thereof are preferred, and succinic acid, itaconic acid, tetrahydrophthalic acid, or anhydrides thereof is more preferable.

Examples of the above (b) tetracarboxylic acid or its acid dianhydride include chain hydrocarbon tetracarboxylic acid or its acid dianhydride, alicyclic tetracarboxylic acid or its acid dianhydride, and aromatic polyvalent Includes carboxylic acid or its acid dianhydride. Furthermore, each hydrocarbon residue (structure excluding a carboxyl group) of these tetracarboxylic acids or their acid dianhydrides may be further substituted with a substituent such as an alkyl group, a cycloalkyl group, or an aromatic group. good.

As specific tetracarboxylic acids, examples of chain hydrocarbon tetracarboxylic acids include butanetetracarboxylic acid, pentanetetracarboxylic acid, hexanetetracarboxylic acid, and the like. Examples of alicyclic tetracarboxylic acids include cyclobutanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, cycloheptanetetracarboxylic acid, norbornanetetracarboxylic acid, and the like. Examples of aromatic polycarboxylic acids include pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, biphenyl ethertetracarboxylic acid, and the like. Acid dianhydrides of these tetracarboxylic acid compounds can also be used.

The molar ratio (a)/(b) of (a) dicarboxylic acid, tricarboxylic acid, or their acid anhydride and (b) tetracarboxylic acid or its acid dianhydride used in the above reaction is 0.01. ~0.5 is preferred, 0.02 ~ 0.3 is more preferred, and 0.03 or more but less than 0.1 is even more preferred. When the molar ratio (a)/(b) is within the above range, it becomes easier to obtain the optimum molecular weight for producing a photosensitive resin composition having good photopatterning properties. Note that the smaller the molar ratio (a)/(b), the higher the alkali solubility and the higher the molecular weight.

Preferably, the ratio at which the epoxy (meth)acrylate resin (c) containing the polymerizable unsaturated group and the carboxylic acid components (a) and (b) are reacted is such that the terminal of the compound becomes a carboxyl group. , each component (c):(a):(b)=1:0.2~1.0:0.01~1.0, preferably 1:0.2~0.4:0.4~ It is desirable to react quantitatively so that the ratio becomes 0.8. In this case, it is possible to react quantitatively so that the molar ratio (c)/[(a)/2+(b)] of the total amount of acid components to the epoxy (meth)acrylate resin is 0.5 to 1.0. desirable. If this molar ratio is less than 0.5, the terminal of the alkali-soluble resin becomes an acid anhydride, and there is a concern that the content of unreacted acid dianhydride increases and the stability of the alkali-soluble resin composition deteriorates over time. be done. On the other hand, if the molar ratio exceeds 1.0, the content of the hydroxyl group-containing compound containing an unreacted polymerizable unsaturated group increases, and there is a concern that the stability of the alkali-soluble resin composition over time may deteriorate. The molar ratio of each component (a), (b), and (c) can be arbitrarily changed within the above-mentioned range for the purpose of adjusting the acid value and molecular weight of the alkali-soluble resin.
In addition, a preferred embodiment from another point of view is that the carboxyl group (acid anhydride group is 2 moles of acid anhydride group) of the carboxylic acid component [(a) + (b)] per 1 mole of hydroxyl group of the epoxy (meth)acrylate resin (c). The reaction is carried out quantitatively so that the total amount of carboxyl groups (calculated as carboxyl groups) is 0.1 to 1.0 mol, preferably 0.5 to 1.0 mol.

The reaction with (a) dicarboxylic acid, tricarboxylic acid, or their acid anhydride, and (b) tetracarboxylic acid or its acid dianhydride can be carried out using a catalyst such as triethylamine, tetraethylammonium bromide, and triphenylphosphine. The reaction can be carried out by heating at 90 to 130° C. and stirring in the presence of the compound.

The polymerizable unsaturated group-containing alkali-soluble resin produced by the above production method preferably has an acid value of 30 to 200 mgKOH/g, more preferably 50 to 150 mgKOH/g. If the oxidation is less than 30 mgKOH/g, residues tend to remain during alkaline development, and if it exceeds 200 mgKOH/g, the alkaline developer penetrates too quickly and peeling development may occur.

In the above-mentioned production method, from the viewpoint of lowering the viscosity of the alkali-soluble resin containing a polymerizable unsaturated group to be produced, it is preferable that the content of n = 0 in general formula (5) is 50% or more. , more preferably 70% or more, even more preferably 85% or more, particularly preferably 95% or more. Further, n is within the range of 0 to 5 on average, preferably within the range of 0 to 2, more preferably within the range of 0 to 1, and within the range of 0 to 0.5. It is particularly preferable that there be.

Moreover, it is preferable that the polymerizable unsaturated group-containing alkali-soluble resin produced by the above-mentioned production method has a hydrolyzable halogen content of 0.2% by mass or less. When the hydrolyzable halogen content is 0.2% by mass or less, the curing reaction is less likely to be inhibited by the hydrolyzable halogen, and the physical properties of the cured product, especially the insulation reliability, are less likely to deteriorate. Preferred for use. The hydrolyzable halogen content is preferably 0.1% by mass or less, more preferably 0.05% by mass or less.

In the above-mentioned manufacturing method, for example, in general formula (5), when n=0, an epoxy (meth)acrylate resin represented by the above general formula (1) is obtained; A polymerizable unsaturated group-containing alkali-available resin having a structure is produced.
The polymerizable unsaturated group-containing alkali-available resin of the present invention includes not only a resin having the structure represented by general formula (2), but also a resin having a different degree of polymerization produced at each stage of the above manufacturing method, or a resin derived therefrom. It can be a resin contained.

However, the epoxy resin obtained by the above manufacturing method may also contain a component where n=1 or more in general formula (5). Since the epoxy (meth)acrylate resin obtained from these epoxy resins with n=1 or more contains three or more hydroxyl groups, it is difficult to react with anhydrides, especially with (b) tetracarboxylic acid or its acid dianhydride. This may make it difficult to control the increase in molecular weight. Note that this polymerizable unsaturated group-containing alkali-available resin is represented by the following formula (7). This polymerizable unsaturated group-containing alkali-available resin is a mixture of oligomers with various molecular weights, and since L ³ in the following formula (7a) is bonded as either L ¹ or L ² of another molecule, the general formula ( Polymerization progresses in structures other than 2). However, as long as the content of n=0 epoxy resin is within the range described above, even if these components are contained, the effects of the present invention will not be affected.

式中、Ｒ^２は一般式（１）のＲ^２と同義であり、Ｘ及びＺは一般式（２）のＸ及びＺと同義であり、ｎは一般式（５）のｎと同義であり、Ｌ¹及びＬ^２は水素原子、上記式（７ａ）又は上記式（３）のいずれかであるが、全てが水素原子ではない。Ｌ^３は他分子のＬ¹又はＬ^２として結合する。

In the formula, R ² has the same meaning as R ² in general formula (1), X and Z have the same meanings as X and Z in general formula (2), and n has the same meaning as n in general formula (5). , L ¹ and L ² are hydrogen atoms, either of the above formula (7a) or the above formula (3), but not all of them are hydrogen atoms. L ³ binds to other molecules as L ¹ or L ² .

[Photosensitive resin composition]
The photosensitive resin composition of the present invention contains the following components (A) to (D).
(A) a polymerizable unsaturated group-containing alkali-soluble resin having a structure represented by general formula (2);
(B) a photopolymerizable monomer having at least two polymerizable unsaturated groups;
(C) Photoinitiator, and (D) Solvent

(B) Examples of photopolymerizable monomers having at least two polymerizable unsaturated groups include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol Di(meth)acrylate, Tetramethylene glycol di(meth)acrylate, Trimethylolpropane tri(meth)acrylate, Trimethylolethane tri(meth)acrylate, Pentaerythritol di(meth)acrylate, Pentaerythritol tri(meth)acrylate, Penta Erythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, glycerol(meth)acrylate, sorbitol penta(meth)acrylate, dipentaerythritol penta(meth)acrylate, or dipentaerythritol hexa(meth)acrylate, sorbitol hexa (Meth)acrylic acid esters including (meth)acrylate, alkylene oxide-modified hexa(meth)acrylate of phosphazene, and caprolactone-modified dipentaerythritol hexa(meth)acrylate, polyhydric alcohols including pentaerythritol, dipentaerythritol, etc. , vinylbenzyl ether compounds of polyhydric phenols such as phenol novolak, and addition polymers of divinyl compounds such as divinylbenzene. When it is necessary to form a crosslinked structure between molecules of the alkali-soluble resin containing polymerizable unsaturated groups, it is more preferable to use a photopolymerizable monomer having three or more polymerizable unsaturated groups. These photopolymerizable monomers may be used alone or in combination of two or more. Note that (B) the photopolymerizable monomer having at least two polymerizable unsaturated groups does not have a free carboxyl group.

The blending ratio of component (B) is preferably 5 to 400 parts by weight, preferably 10 to 150 parts by weight, per 100 parts by weight of component (A). If the blending ratio of component (B) is more than 400 parts by mass per 100 parts by mass of component (A), the cured product after photocuring will become brittle, and the acid value of the coating film will be low in the unexposed areas. The solubility in an alkaline developer decreases, causing problems such as pattern edges becoming jagged and not sharp. On the other hand, if the blending ratio of component (B) is less than 5 parts by mass per 100 parts by mass of component (A), the proportion of photoreactive functional groups in the resin will be small and the formation of a crosslinked structure will not be sufficient, and Due to the high acid value of the resin component, the solubility in the alkaline developer in the exposed area increases, resulting in the formed pattern being thinner than the target line width or more likely to be missing. Problems may occur.

(C) Examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, and pt-butylacetophenone. acetophenones, including benzophenone, 2-chlorobenzophenone, and p,p'-bisdimethylaminobenzophenone; benzoin ethers, including benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; 2-(o-chlorophenyl)-4,5-phenylbiimidazole, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)biimidazole, 2-(o-fluorophenyl)-4,5 - Biimidazole compounds including diphenylbiimidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, and 2,4,5-triarylbiimidazole, 2-trichloromethyl-5-styryl -1,3,4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazole, and 2-trichloromethyl-5-(p-methoxystyryl)- Halomethyldiazole compounds including 1,3,4-oxadiazole, 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl) methyl)-1,3,5-triazine, 2-phenyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-chlorophenyl)-4,6-bis(trichloromethyl) -1,3,5-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-bis (trichloromethyl)-1,3,5-triazine, 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4,5-triazine) methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, etc. Halomethyl-s-triazine compounds including 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(O-benzoyloxime), 1-(4-phenylsulfanylphenyl)butane- 1,2-dione-2-oxime-O-benzoate, 1-(4-methylsulfanylphenyl)butane-1,2-dione-2-oxime-O-acetate, 1-(4-methylsulfanylphenyl)butane -1-one oxime-O-acetate, ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(0-acetyloxime), methanone, (9 -ethyl-6-nitro-9H-carbazol-3-yl)[4-(2-methoxy-1-methylethoxy)-2-methylphenyl]-, O-acetyloxime, methanone, (2-methylphenyl)( 7-nitro-9,9-dipropyl-9H-fluoren-2-yl)-, acetyloxime, ethanone, 1-[7-(2-methylbenzoyl)-9,9-dipropyl-9H-fluoren-2-yl ]-, 1-(O-acetyloxime), and O- including ethanone, 1-(-9,9-dibutyl-7-nitro-9H-fluoren-2-yl)-, 1-O-acetyloxime, etc. Acyloxime compounds, benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, sulfur compounds including 2-isopropylthioxanthone, etc., 2-ethyl Anthraquinones such as anthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, and 2,3-diphenylanthraquinone, organic peroxides including azobisisobutylnitrile, benzoyl peroxide, and cumene peroxide, 2-mercaptobenzimidazole , 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, and the like. These photoinitiators may be used alone or in combination of two or more. Note that the photopolymerization initiator as used in the present invention is used to include a sensitizer.

(C) As a photopolymerization initiator, a compound that does not act as a photopolymerization initiator or sensitizer by itself, but can increase the ability of the photopolymerization initiator or sensitizer when used in combination. can also be added. Examples of such compounds include tertiary amines such as triethanolamine and triethylamine, which are effective when used in combination with benzophenone.

The blending ratio of component (C) is preferably 0.1 to 30 parts by mass, preferably 1 to 25 parts by mass, based on the total of 100 parts by mass of components (A) and (B). good. If the blending ratio of component (C) is less than 0.1 part by mass, the speed of photopolymerization will be slow and the sensitivity will decrease, while if it exceeds 30 parts by mass, the sensitivity will be too strong. The pattern line width becomes thicker than the pattern mask, which may cause problems such as the line width not being able to be reproduced faithfully to the mask, or the pattern edges being jagged and not being sharp.

(D) Examples of solvents include methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol, 3-methoxy-1-butanol, ethylene glycol monobutyl ether, 3-hydroxy-2-butanone, and diacetone alcohol. terpenes, etc., including α- or β-terpineol, ketones, including acetone, methyl ethyl ketone, cyclohexanone, and N-methyl-2-pyrrolidone, toluene, xylene, and tetramethylbenzene, etc. Aromatic hydrocarbons, glycols including cellosolve, methyl cellosolve, ethyl cellosolve, carbitol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, etc. Ethers, ethyl acetate, butyl acetate, ethyl lactate, 3-methoxybutyl acetate, 3-methoxy-3-butyl acetate, cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, ethyl carbitol acetate, butyl carbitol acetate , propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and the like. These solvents may be used alone or in combination of two or more in order to satisfy properties such as coatability.

In addition, the photosensitive resin composition may contain curing accelerators, thermal polymerization inhibitors, antioxidants, plasticizers, fillers, leveling agents, antifoaming agents, coupling agents, surfactants, etc. as necessary. Additives can be added. As the curing accelerator, for example, known compounds known as curing accelerators, curing catalysts, latent curing agents, etc. that are commonly applied to epoxy resins can be used, and examples include tertiary amines, quaternary ammonium salts, tertiary phosphines, quaternary phosphines, etc. These include class phosphonium salts, boric acid esters, Lewis acids, organometallic compounds, imidazoles, diazabicyclo compounds, and the like. Examples of thermal polymerization inhibitors and antioxidants include hydroquinone, hydroquinone monomethyl ether, pyrogallol, t-butylcatechol, phenothiazine, hindered phenol compounds, phosphorus thermal stabilizers, and the like. Examples of plasticizers include dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, and the like. Examples of fillers include glass fiber, silica, mica, alumina, and the like. Examples of leveling agents and antifoaming agents include silicone-based, fluorine-based, and acrylic-based compounds. Examples of coupling agents include vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-(glycidyloxy)propyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane. , 3-aminopropyltriethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-ureidopropyltriethoxysilane, and other silane coupling agents. Examples of surfactants include fluorosurfactants, silicone surfactants, and the like.

The above photosensitive resin composition can also contain (v) an epoxy resin having two or more epoxy groups or an epoxy resin in addition to (A) to (D). Examples of such epoxy resins or epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, bisphenol fluorene type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin. type epoxy resin, glycidyl ether of polyhydric alcohol, glycidyl ester of polyhydric carboxylic acid, polymer containing glycidyl (meth)acrylate as a unit, 3,4-epoxycyclohexanecarboxylic acid [(3,4-epoxycyclohexyl)methyl ], 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol (e.g. "EHPE3150", Daicel Co., Ltd.) (manufactured by Nippon Soda Co., Ltd.), phenyl glycidyl ether, p-butylphenol glycidyl ether, triglycidyl isocyanurate, diglycidyl isocyanurate, epoxidized polybutadiene (for example, "NISSO-PB JP-100", manufactured by Nippon Soda Co., Ltd.), epoxy having a silicone skeleton Contains resin. These components are preferably compounds having an epoxy equivalent of 100 to 300 g/eq and a number average molecular weight of 100 to 5,000. As component (v), only one type of compound may be used, or two or more types may be used in combination. When it is necessary to increase the crosslinking density of the alkali-soluble resin, a compound having at least two or more epoxy groups is preferred.

When using the epoxy resin (v), the amount added is preferably 10 to 40 parts by weight based on the total of 100 parts by weight of components (A) and (B). Here, one purpose of adding epoxy resin is to reduce the amount of carboxyl groups remaining when forming a cured film after patterning in order to increase the reliability of the cured film. If the amount of epoxy resin added is less than 10 parts by mass, there is a risk that moisture resistance reliability cannot be ensured when used as an insulating film, for example. In addition, if the amount of the epoxy resin is more than 40 parts by mass, the amount of photosensitive groups in the resin component in the photosensitive resin composition may decrease, and there is a risk that sufficient sensitivity for patterning may not be obtained. .

The photosensitive resin composition contains the components (A) to (D) or the components (A) to (v) as main components. It is desirable that the solid content contains components (A) to (C) and (v) in a total of 70% by mass, preferably 80% by mass or more. The amount of the solvent (D) varies depending on the target viscosity, but it is preferably contained in the photosensitive resin composition in the range of 60 to 90% by mass.

[Cured product]
The above-mentioned photosensitive resin composition is, for example, applied to a substrate etc., dried, irradiated with light (including ultraviolet rays, radiation, etc.) (exposure), and cured to form a cured product (coating film). be able to. At this time, if you use a photomask etc. to set up areas that are exposed to light and areas that are not, and cure only the areas that are exposed to light and dissolve the other areas with an alkaline solution, you can create a cured product with the desired pattern. (Coating film) is obtained.

Specifically, when applying the photosensitive resin composition to the substrate, any method such as a known solution dipping method, spray method, method using a roller coater machine, land coater machine, slit coater machine, or spinner machine can be used. can also be adopted.

By these methods, a film is formed by applying a photosensitive resin composition to a desired thickness and then removing the solvent (prebaking). Prebaking is performed by heating using an oven, hot plate, etc., vacuum drying, or a combination thereof. The heating temperature and heating time in prebaking are appropriately selected depending on the solvent used, and is carried out, for example, at a temperature of 80 to 120° C. for 1 to 10 minutes.

Examples of radiation used for exposure include visible light, ultraviolet rays, far ultraviolet rays, electron beams, and X-rays, but radiation with a wavelength in the range of 250 to 450 nm is preferred.

Alkaline development can be carried out using, for example, an aqueous solution of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, tetramethylammonium hydroxide, or the like as a developer. These developing solutions are selected depending on the characteristics of the resin layer, and a surfactant may be added if necessary. The development is preferably carried out at a temperature of 20 to 35°C. By using a commercially available developing machine, ultrasonic cleaning machine, etc., fine images can be precisely formed. Note that after alkaline development, the film is usually washed with water. Examples of development processing methods include shower development, spray development, dip development, paddle development, and the like.

After developing in this manner, heat treatment (post-bake) is performed at a temperature of 180 to 250° C. for 20 to 100 minutes. This post-baking is performed for the purpose of increasing the adhesion between the patterned coating film and the substrate. Post-baking, like pre-baking, is performed by heating with an oven, hot plate, or the like.

Thereafter, polymerization or curing (both may be collectively referred to as curing) is completed by heat to obtain a cured film such as an insulating film. The curing temperature at this time is preferably in the range of 160 to 250°C.

The above-mentioned cured product can be used for resist layers such as solder resist layers, plating resist layers, and etching resist layers, interlayer insulation layers such as multilayer printed wiring boards, gas barrier films, lenses, and semiconductor light emitting devices such as light emitting diodes (LEDs). It can also be used as a sealant, a top coat for paints and inks, a hard coat for plastics, a rust preventive film for metals, etc.

Hereinafter, embodiments of the present invention will be specifically described based on Examples and Comparative Examples, but the present invention is not limited thereto. In the examples, unless otherwise specified, "parts" represent parts by mass, and "%" represent mass %. In addition, evaluation of the resins in the synthesis examples was performed as follows unless otherwise specified.

[Solid content concentration]
A glass filter [mass: W0 (g)] was impregnated with 1 g of the resin solution, photosensitive resin composition, etc. obtained in the synthesis example (and comparative synthesis example) and weighed [W1 (g)], and the mixture was heated to 160°C. It was calculated from the mass [W2 (g)] after heating for 2 hours using the following formula.
Solid content concentration (mass%) = 100 x (W2-W0)/(W1-W0)

[Acid value]
The resin solution was dissolved in dioxane and titrated with a 0.1N KOH aqueous solution using a potentiometric titration device (COM-1600 manufactured by Hiranuma Sangyo Co., Ltd.) to determine the amount of KOH required per 1 g of solid content. It was taken as acid value.

[Molecular weight]
Gel permeation chromatography (GPC) (HLC-8220GPC manufactured by Tosoh Corporation, solvent: tetrahydrofuran, column: TSKgelSuperH-2000 (2 pieces) + TSKgelSuperH-3000 (1 piece) + TSKgelSuperH-4000 (1 piece) + TSKgelSuper-H5 000( 1 bottle) (manufactured by Tosoh Corporation), temperature: 40°C, speed: 0.6 mL/min), and the weight average molecular weight (Mw ) is the value obtained.

Further, the abbreviations used in the synthesis examples and comparative synthesis examples are as follows.
DPXLEA: A reaction product of epoxy resin (epoxy equivalent: 271, having a skeleton of general formula (1)) obtained by reacting epichlorohydrin with a diphenol compound obtained by crosslinking 2,6-xylenol with dicyclopentadiene and acrylic acid ( Equivalent reaction product of epoxy group and carboxyl group)
BPAEA: Reaction product of bisphenol A type epoxy resin (epoxy equivalent: 182) and acrylic acid (equal equivalent reaction product of epoxy group and carboxyl group)
BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride THPA: 1,2,3,6-tetrahydrophthalic anhydride TEAB: Tetraethylammonium bromide PGMEA: Propylene glycol monomethyl ether acetate

Example 1
In a reaction vessel equipped with a stirrer, a temperature control device, a reflux condenser, and an air introduction device, add 450 parts of a 50% PGMEA solution of DPXLEA, 49 parts of BPDA, 25 parts of THPA, 0.69 parts of TEAB, and PGMEA. 20 parts of were charged and stirred for 6 hours while heating at 120 to 125°C to obtain an alkali-soluble resin (A1). The resulting resin had a solid content concentration of 55%, an acid value (solid content equivalent) of 92 mgKOH/g, and a molecular weight (Mw) of 3500.

Comparative example 1
Into the same apparatus as in Example 1, 291 parts of a 50% PGMEA solution of BPAEA, 4 parts of dimethylolpropionic acid, 11.8 parts of 1,6-hexanediol, and 84 parts of PGMEA were charged, and the temperature was raised to 45°C. It was warm. Next, 61.8 parts of isophorone diisocyanate was added dropwise while paying attention to the temperature inside the flask. After the dropwise addition was completed, the mixture was stirred for 6 hours under heating at 75 to 80°C. Furthermore, 21 parts of THPA was charged and stirred for 6 hours under heating at 90 to 95°C to obtain an alkali-soluble resin solution (HA1). The resulting resin had a solid content concentration of 66.5%, an acid value (solid content equivalent) of 38.4 mgKOH/g, and a molecular weight (Mw) of 12,220.

Next, the present invention will be specifically explained based on Examples and Comparative Examples concerning photosensitive resin compositions and cured products, but the present invention is not limited thereto. Here, the raw materials and abbreviations used in the following Examples and Comparative Examples are as follows.

(A1): Alkali-soluble resin obtained in the above Example 1 (HA1): Alkali-soluble resin obtained in the above Comparative Example 1 (HA2): 68.9% PGMEA solution of cresol novolac type acid-modified epoxy acrylate resin ( CCR-1172, manufactured by Nippon Kayaku Co., Ltd.)
(B): Dipentaerythritol hexaacrylate (C1): Irgacure 184 (manufactured by BASF)
(C2): 4,4'-bis(dimethylamino)benzophenone (Michler ketone)
(D): Propylene glycol monomethyl ether acetate (E): Cresol novolac type epoxy resin (manufactured by Nippon Steel Chemical & Materials Co., Ltd., YDCN-700-3, epoxy equivalent: 203 g/eq., softening point: 73°C)

The above ingredients were blended in the proportions shown in Table 1 to prepare photosensitive resin compositions of Example 2 and Comparative Examples 2 and 3. In addition, all the numerical values in Table 1 represent parts by mass.

The photosensitive resin composition shown in Table 1 was coated on a 125 mm x 125 mm glass substrate using a spin coater so that the film thickness after post-baking was 30 μm, and prebaked at 110°C for 5 minutes to coat the coated plate. It was created. Thereafter, ultraviolet rays with a wavelength of 365 nm were irradiated with a 500 W/cm ² high-pressure mercury lamp through a pattern-forming photomask to perform a photocuring reaction on the exposed portions. Next, this exposed coated plate was developed using a 0.8% tetramethylammonium hydroxide (TMAH) aqueous solution in a shower at 23°C for an additional 30 seconds from the time when the pattern began to appear, and was further spray washed with water. The unexposed areas of the coating were removed. Thereafter, heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain cured films according to Example 2 and Comparative Examples 2 and 3.

The cured film obtained under the above conditions was evaluated as follows. In addition, when creating the cured film for the film thickness test, alkali resistance test, and acid resistance test, after the entire surface was exposed without passing through a photomask, development, water washing, and heat curing treatment were performed.

(film thickness)
A part of the coated film was scraped and measured using a stylus type step shape measuring device (manufactured by KLA-Tencor Co., Ltd., trade name P-10).

(Adhesion)
At least 100 crosscuts were made in a checkerboard pattern on the film of the glass substrate with a cured film, and then a peeling test was conducted using cellophane tape, and the condition of the checkerboard was visually evaluated.
◎: No peeling observed at all ○: Slight peeling of the paint film △: Partial peeling of the paint film ×: Most of the film peeling off

(alkali resistance)
A glass substrate with a cured film is immersed in a solution of a mixed solution of 30 parts by mass of 2-aminoethanol and 70 parts by mass of glycol ether kept at 80°C, pulled out after 10 minutes, washed with pure water, dried, and immersed in chemicals. A sample was prepared and the adhesion was evaluated.

(acid resistance)
A glass substrate with a cured film was immersed in a solution of aqua regia (hydrochloric acid: nitric acid = 7:3) maintained at 50°C, and after 10 minutes it was pulled out, washed with pure water, and dried to create a chemical-immersed sample. The adhesion was evaluated.

(bending test)
The photosensitive resin composition shown in Table 1 was coated using a spin coater on a glass substrate with a 125 mm x 125 mm release film attached so that the film thickness after post-baking would be 30 μm, and then heated at 110°C for 5 minutes. A coated plate was prepared by pre-baking. Thereafter, ultraviolet rays with a wavelength of 365 nm were irradiated with a 500 W/cm ² high-pressure mercury lamp through a pattern-forming photomask to perform a photocuring reaction on the exposed portions. Next, this exposed coated plate was developed with a 0.8wt% tetramethylammonium hydroxide (TMAH) aqueous solution at 23°C for an additional 30 seconds from the time when the pattern began to appear, and was further spray washed with water. The unexposed areas of the coating were removed. Thereafter, heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer, and the resulting pattern was peeled off from the release film to obtain films according to Example 2 and Comparative Examples 2 and 3.

The film obtained under the above conditions was folded in half and then spread out with the top of the fold facing upward. This test was repeated and evaluated based on the number of times cracks or breaks were observed.

From the results of Example 2 and Comparative Examples 2 and 3, it is clear that when the polymerizable unsaturated group-containing alkali-soluble resin of the present invention or the alkali-soluble resin containing the same is used, patterning with excellent resolution is possible by alkaline development, and It can be seen that a cured film with excellent reliability such as folding resistance can be produced.

Claims (6)

Polymerization characterized by reacting an epoxy (meth)acrylate resin represented by the following general formula (1) with a dicarboxylic acid, a tricarboxylic acid, or an acid anhydride thereof, and a tetracarboxylic acid or an acid dianhydride thereof. A method for producing an alkali-soluble resin containing an unsaturated group.

(In the formula, R ¹ represents an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group, and R ² represents a hydrogen atom or a methyl group.) A polymerizable unsaturated group-containing alkali-soluble resin obtained by the production method according to claim 1 and having a structure represented by general formula (2).

(In the formula, ^R2 represents a hydrogen atom or a methyl group, X represents a tetravalent carboxylic acid residue, Y represents a carboxyl group-containing group represented by the above formula (3) or a hydrogen atom, and Z represents It shows a structure represented by the above formula (2a), where m is a number with an average value of 1 to 20. R ¹ is an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group. M is a p+1 valent group. represents a carboxylic acid residue, p is 1 or 2.) The alkali-soluble resin containing a polymerizable unsaturated group according to claim 2, characterized in that it contains a photopolymerizable monomer having at least two polymerizable unsaturated groups, a photopolymerization initiator, and a solvent as essential components. Photosensitive resin composition. The photosensitive resin composition according to claim 3, further comprising an epoxy resin having two or more epoxy groups. Claim 3 or 4 containing 0.1 to 30 parts by mass of a photopolymerization initiator and 10 to 40 parts by mass of a solvent based on a total of 100 parts by mass of the alkali-soluble resin containing a polymerizable unsaturated group and the photopolymerizable monomer. The photosensitive resin composition described in . A cured product obtained by curing the photosensitive resin composition according to any one of claims 3 to 5.