Polymerizable unsaturated group-containing alkali-soluble resin and method for producing the same, as well as photosensitive resin composition and cured product thereof.

Abstract

Provided are: a photosensitive resin composition capable of patterning at exceptional resolution by alkaline development, the photosensitive resin composition yielding a cured product that can be applied to an insulating film, etc., having exceptional chemical resistance and also exceptional reliability such as seam folding resistance; a polymerizable-unsaturated-group-containing alkali-soluble resin used in said photosensitive resin composition; and a method for producing said resin.　A method for producing a polymerizable-unsaturated-group-containing alkali-soluble resin, the method being characterized in that an epoxy (meth)acrylate resin represented by general formula (1) is reacted with a dicarboxylic acid, tricarboxylic acid, or acid anhydride thereof and a tetracarboxylic acid or an acid dianhydride thereof.　Herein, R1 represents a C1-8 alkyl group, a phenyl group, or an allyl group, R2 represents a hydrogen atom or a dicyclopentenyl group, and R3 represents a hydrogen atom or a methyl group.

Description

[Technical Field]

[0001] The present invention relates to a method for producing an alkali-soluble resin containing polymerizable unsaturated groups, an alkali-soluble resin containing polymerizable unsaturated groups, a photosensitive resin composition comprising the same as an essential component, and a cured film obtained by curing the composition. The photosensitive resin composition and its cured product, which contain a specific alkali-soluble resin containing polymerizable unsaturated groups according to the present invention, can be applied as resist layers such as solder resist layers, plating resist layers, and etching resist layers, interlayer insulating layers such as multilayer printed circuit boards, gas barrier films, encapsulants for semiconductor light-emitting elements such as lenses and light-emitting diodes (LEDs), topcoats for paints and inks, hardcoats for plastics, and rust-preventive films for metals. [Background technology]

[0002] In recent years, with the increasing performance and resolution of electronic devices and display components, there has been a demand for miniaturization and higher density in the electronic components used therein. Furthermore, the processability of the insulating materials used in these devices is also being challenged, with demands for miniaturization and optimization of the cross-sectional shape of the processed patterns. Patterning by exposure and development is a known effective method for microfabrication of insulating materials, and photosensitive resin compositions have been used in this process. However, there is a growing demand for many other properties, such as high sensitivity, adhesion to the substrate, reliability, heat resistance, and chemical resistance. In addition, various studies have been conducted on using organic insulating materials in gate insulating films for organic TFTs. However, there is a need to reduce the operating voltage of the organic TFT by thinning the gate insulating film, and for organic insulating materials with a dielectric breakdown voltage of generally around 1 MV / cm, the application of thin films of about 0.2 μm is being considered.

[0003] Conventional insulating materials made from photosensitive resin compositions utilize a photocuring reaction between a photoreactive alkali-soluble resin and a photopolymerization initiator. The i-line (365 nm), one of the line spectra of mercury lamps, is mainly used as the exposure wavelength for photocuring. However, this i-line is absorbed by the photosensitive resin itself and the colorant, resulting in a decrease in the degree of photocuring. Moreover, this absorption increases with thicker films. As a result, a difference in crosslinking density occurs in the film thickness direction in the exposed areas. Even if sufficient photocuring occurs on the surface of the coating, photocuring is difficult at the bottom of the coating, making it extremely difficult to create a difference in crosslinking density between the exposed and unexposed areas. This deteriorates pattern dimensional stability, development margin, pattern adhesion, pattern edge shape, and cross-sectional shape, making it difficult to obtain a photosensitive insulating material that can be developed at high resolution.

[0004] Generally, photosensitive resin compositions used in such applications contain polyfunctional photocurable monomers having polymerizable unsaturated bonds, alkali-soluble binder resins, photopolymerization initiators, etc., and photosensitive resin compositions disclosed in technical documents for use as color filter materials can be applied. For example, Patent Documents 1 and 2 disclose copolymers in which a predetermined unsaturated organic acid ester and an unsaturated organic acid are constituent components as binder resins. Furthermore, Patent Document 3 discloses that alkali-soluble unsaturated compounds having polymerizable unsaturated double bonds and carboxyl groups in one molecule are effective for forming negative patterns in color filters and the like.

[0005] On the other hand, Patent Documents 4, 5, 6, and 7 disclose liquid resins using reaction products of epoxy (meth)acrylate having a bisphenol fluorene structure and acid anhydride. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 61-213213 [Patent Document 2] Japanese Patent Application Publication No. 1-152449 [Patent Document 3] Japanese Patent Application Publication No. 4-340965 [Patent Document 4] Japanese Patent Application Publication No. 4-345673 [Patent Document 5] Japanese Patent Application Publication No. 4-345608 [Patent Document 6] Japanese Patent Application Publication No. 4-355450 [Patent Document 7] Japanese Patent Application Publication No. 4-363311

[0007] However, the copolymers disclosed in Patent Documents 1 and 2 are random copolymers, which results in a distribution of alkali dissolution rates within the light-irradiated and un-irradiated areas. This narrows the margin during development, making it difficult to obtain sharp-angled pattern shapes or fine patterns. In particular, when high concentrations of pigment are included, the exposure sensitivity decreases significantly, making it impossible to obtain fine negative-type patterns.

[0008] Furthermore, the alkali-soluble unsaturated compound described in Patent Document 3 is expected to be more sensitive than the aforementioned combination of binder resin and polyfunctional polymerizable monomer because it becomes insoluble upon light irradiation. However, the compound exemplified here is obtained by arbitrarily adding polymerizable unsaturated groups such as acrylic acid and acid anhydride to the hydroxyl group of a phenol oligomer. In such a case, a wide distribution can be created in the molecular weight and amount of carboxyl groups of each molecule, resulting in a wide distribution of the alkali dissolution rate of the alkali-soluble resin, making it difficult to form a fine negative pattern.

[0009] Furthermore, the resins exemplified in Patent Documents 4, 5, 6, and 7 are reaction products of epoxy (meth)acrylate and acid anhydride, and therefore have small molecular weights. As a result, it is difficult to increase the difference in alkali solubility between the exposed and unexposed areas, and it is not possible to form fine patterns.

[0010] Thus, photolithography using various photosensitive resin compositions has been used as a method for microfabricating insulating materials. However, after achieving pattern miniaturization and shape optimization, the formed insulating film is required to have many characteristics such as adhesion to the substrate, reliability, heat resistance, chemical resistance, etc. For example, haze folding resistance may be required as in the case of using flexible displays and touch panels, and it has become necessary to provide a material with excellent chemical resistance required in electrode processing processes after forming the insulating film.

Summary of the Invention

Problems to be Solved by the Invention

[0011] The present invention provides a photosensitive resin composition that enables patterning with excellent resolution by alkali development, and also has excellent chemical resistance when it is necessary to undergo a processing process such as electrode formation after forming an insulating film in a touch panel manufacturing process, etc. Moreover, it is an object of the present invention to provide a photosensitive resin composition that can be applied to an insulating film with excellent reliability such as haze folding resistance. Another object is to provide a method for producing a polymerizable unsaturated group-containing alkali-soluble resin used in this photosensitive resin composition, the polymerizable unsaturated group-containing alkali-soluble resin produced by this production method, and a cured film obtained by curing this photosensitive resin composition.

Means for Solving the Problems

[0012] The inventors of the present invention have found that it is effective to use a photosensitive resin composition containing a polymerizable unsaturated group-containing alkali-soluble resin having a specific alicyclic structure to solve the above problems, and have completed the present invention.

[0013] The present invention relates to a method for producing a polymerizable unsaturated group-containing alkali-soluble resin, which comprises reacting an epoxy (meth) acrylate resin represented by the following general formula (1) with (a) a dicarboxylic acid, a tricarboxylic acid or their acid anhydrides, and (b) a tetracarboxylic acid or its acid dianhydride.

[0014] [ka] Here, R 1 These independently represent an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group. R 2 Each of these independently represents a hydrogen atom or a dicyclopentenyl group, and one or more of them are dicyclopentenyl groups. R 3 represents a hydrogen atom or a methyl group.

[0015] Another embodiment of the present invention relates to a polymerizable unsaturated group-containing alkali-soluble resin obtained by the above manufacturing method, the polymerizable unsaturated group-containing alkali-soluble resin having a structure represented by general formula (2).

[0016] [ka] Here, X represents a tetravalent carboxylic acid residue, Y represents a carboxyl group-containing group or hydrogen atom represented by the above formula (3), Z represents the structure shown in equation (2a) above, m is a number whose average value is between 1 and 20. R 1 This represents an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group. R 2 Each of these independently represents a hydrogen atom or a dicyclopentenyl group, and one or more of them are dicyclopentenyl groups. R 3 represents a hydrogen atom or a methyl group. M represents a p+1 valent carboxylic acid residue, where p is 1 or 2.

[0017] Furthermore, other embodiments of the present invention are: (A) The above polymerizable unsaturated group-containing alkali-soluble resin, (B) A photopolymerizable monomer having at least two polymerizable unsaturated groups, (C) Photopolymerization initiator, and (D) Solvent The present invention relates to a photosensitive resin composition characterized by containing as an essential component.

[0018] Another embodiment of the present invention relates to a cured product obtained by curing the above-mentioned photosensitive resin composition. [Effects of the Invention]

[0019] The photosensitive resin composition of the present invention, which uses an alkali-soluble resin containing polymerizable unsaturated groups having a specific alicyclic structure, can be patterned by alkali development, and the cured product has a low modulus of elasticity and excellent seam folding properties, making it suitable for use as an insulating film for flexible displays and touch panels. Furthermore, it can provide a cured product pattern with excellent chemical resistance when processing steps such as electrode formation are required after forming an insulating film in touch panel manufacturing processes, etc. [Modes for carrying out the invention]

[0020] The present invention will be described in detail below. One embodiment of the present invention relates to a method for producing a polymerizable unsaturated group-containing alkali-soluble resin by reacting an epoxy (meth)acrylate resin represented by general formula (1) with (a) a dicarboxylic acid, a tricarboxylic acid or an acid anhydride thereof, and (b) a tetracarboxylic acid or an acid dianhydride thereof, and to the polymerizable unsaturated group-containing alkali-soluble resin produced by this method.

[0021] In general formula (1), R 1 The substituents independently represent an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group. The alkyl group having 1 to 8 carbon atoms may be linear, branched, or cyclic, and examples include, but are not limited to, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, a hexyl group, a cyclohexyl group, and a methylcyclohexyl group. Among these substituents, a phenyl group and a methyl group are preferred from the viewpoint of availability and reactivity when cured, and a methyl group is particularly preferred.

[0022] R 2independently represents a hydrogen atom or a dicyclopentenyl group, and one or more of them are dicyclopentenyl groups. The dicyclopentenyl group is a group derived from dicyclopentadiene and is represented by the following formula (1а) or formula (1b).

Chemical formula

[0023] The raw material of the above epoxy (meth) acrylate resin is obtained by reacting a dicyclopentadiene-type epoxy resin with (meth) acrylic acid (which refers to 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 carry out epoxidation. This diphenol compound can be obtained by reacting a 2,6-disubstituted phenol compound with dicyclopentadiene in the presence of a catalyst such as boron trifluoride-ether complex.

Chemical formula

[0024] The above diphenol compound can be obtained by adding preferably 0.28 to 2.0 moles, more preferably 0.28 to 1.0 moles, and still more preferably 0.3 to 0.5 moles of dicyclopentadiene to 1 mole of the 2,6-disubstituted phenol compound and reacting in the presence of a catalyst.

[0025] Examples of the above 2,6-disubstituted phenol compounds include 2,6-dimethylphenol, 2,6-diethylphenol, 2,6-dipropylphenol, 2,6-diisopropylphenol, 2,6-di(n-butyl)phenol, 2,6-di(t-butyl)phenol, 2,6-dihexylphenol, 2,6-dicyclohexylphenol, and 2,6-diphenylphenol. However, 2,6-dimethylphenol is preferred from the viewpoint of ease of acquisition and reactivity when cured.

[0026] The acid catalyst used when reacting a 2,6-disubstituted phenol compound with dicyclopentadiene is a Lewis acid, specifically a boron trifluoride compound such as boron trifluoride, boron trifluoride-phenol complex, or boron trifluoride-ether complex; metal chlorides such as aluminum chloride, tin chloride, zinc chloride, titanium tetrachloride, and iron chloride; or organic sulfonic acids such as methanesulfonic acid, ethanesulfonic acid, and propanesulfonic acid. Among these, boron trifluoride-ether complex is preferred due to its ease of handling. The amount of acid catalyst used is 0.001 to 20 parts by mass, preferably 0.5 to 10 parts by mass, per 100 parts by mass of dicyclopentadiene in the case of boron trifluoride-ether complex.

[0027] A suitable reaction method involves charging a 2,6-disubstituted phenol compound and a catalyst into a reactor and gradually adding dicyclopentadiene dropwise over 1 to 10 hours. The reaction temperature is preferably 50 to 200°C, more preferably 100 to 180°C, and even more preferably 120 to 160°C. The reaction time is preferably 1 to 10 hours, more preferably 3 to 10 hours, and even more preferably 4 to 8 hours.

[0028] After the reaction is complete, alkalis such as sodium hydroxide and potassium hydroxide are added to deactivate the catalyst, and then the unreacted 2,6-disubstituted phenol compound is recovered under reduced pressure.

[0029] Subsequently, to separate and purify the reaction product, solvents such as toluene, xylene, methyl ethyl ketone, and methyl isobutyl ketone are added to dissolve the product, and after washing with water, the solvent and unreacted raw materials are recovered under reduced pressure to obtain the desired diphenol compound.

[0030] Furthermore, during the reaction, solvents such as benzene, toluene, xylene, chlorobenzene, dichlorobenzene, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether may be used as needed for viscosity adjustment and other purposes.

[0031] To confirm that the dicyclopentenyl group has been introduced into the above-mentioned diphenol compound, mass spectrometry and FT-IR measurement can be used.

[0032] When using mass spectrometry, electrospray mass spectrometry (ESI-MS) or field desorption (FD-MS) can be employed. By subjecting a sample, in which components with different numbers of nuclei have been separated by GPC or similar methods, to mass spectrometry, it is possible to confirm the introduction of dicyclopentenyl groups.

[0033] When using the FT-IR measurement method, a sample dissolved in an organic solvent such as tetrahydrofuran is coated onto a KRS-5 cell, and the sample thin film attached to the cell, obtained by drying the organic solvent, is measured by FT-IR. A peak originating from CO stretching vibrations in the phenol nucleus is observed at 1210 cm⁻¹. -1 A peak appears in the vicinity, and only when a dicyclopentenyl group is introduced, originating from the CH stretching vibration of the olefin moiety of the dicyclopentadiene skeleton, at 30-40 cm⁻¹. -1 It appears in the vicinity. Using a straight line connecting the beginning and end of the target peak as the baseline, and the distance from the peak's summit to the baseline as the peak height, the result is 3040 cm. -1 Nearby peak (A 3040 ) and 1210cm -1 Nearby peak (A 1210 ) ratio (A 3040 / A 1210The amount of dicyclopentenyl group introduced can be quantified by ). It has been confirmed that the higher the ratio, the better the physical properties, and a preferred ratio (A) is obtained to satisfy the desired physical properties. 3040 / A 1210 ) is 0.05 or greater, and more preferably 0.1 or greater.

[0034] By reacting the diphenol compound obtained by the above method with an epihalohydrin, a dicyclopentadiene-type epoxy resin can be obtained. This reaction is carried out according to a conventionally known method.

[0035] For example, it can be obtained by adding an alkali metal hydroxide such as sodium hydroxide in solid form or as a concentrated aqueous solution to a mixture of a diphenol compound and an excess molar amount of epihalohydrin relative to the hydroxyl groups of the diphenol compound, and reacting at a reaction temperature of 30 to 120°C for 0.5 to 10 hours, or by adding a quaternary ammonium salt such as tetraethylammonium chloride as a catalyst to a polyhalohydrin ether obtained by reacting a diphenol compound and an excess molar amount of epihalohydrin at a temperature of 50 to 150°C for 1 to 5 hours, and then adding an alkali metal hydroxide such as sodium hydroxide in solid form or as a concentrated aqueous solution, and reacting at a temperature of 30 to 120°C for 1 to 10 hours.

[0036] In the above reaction, the amount of epihalohydrin used is 1 to 10 times the molar amount relative to the hydroxyl groups of the diphenol compound, preferably in the range of 2 to 5 times the molar amount, and the amount of alkali metal hydroxide used is in the range of 0.85 to 1.1 times the molar amount relative to the hydroxyl groups of the diphenol compound.

[0037] The epoxy resin obtained from these reactions contains unreacted epihalohydrins and alkali metal halides. Therefore, the unreacted epihalohydrins are removed from the reaction mixture by evaporation, and the alkali metal halides are further removed by methods such as extraction with water or filtration to obtain the desired epoxy resin. The epoxy resin obtained in this way is a dicyclopentadiene type epoxy resin and is represented by the following general formula (5).

[0038] [ka] Here, R 1 and R 2 These are equivalent to the definitions in the general formula (1) above, n is the number of repetitions, representing a number between 0 and 5 on average.

[0039] The epoxy equivalent (g / eq.) of the above epoxy resin is preferably 244 to 3700, more preferably 260 to 2000, and even more preferably greater than 270 and less than 700.

[0040] The molecular weight distribution of the resulting epoxy resin can be altered by changing the ratio of diphenol compound to epihalohydrin used in the epoxidation reaction. The closer the amount of epihalohydrin used is to equimolar relative to the hydroxyl groups of the diphenol compound, the higher the molecular weight distribution becomes, while the closer it is to 20 times the molar ratio, the lower the molecular weight distribution becomes. Furthermore, it is possible to increase the molecular weight of the resulting epoxy resin by reacting it again with the diphenol compound. However, in order to appropriately control the molecular weight of the polymerizable unsaturated group-containing alkali-soluble resin of the present invention, it is preferable that the content of the n=0 compound in general formula (5) be 50% or more, more preferably 70% or more, even more preferably 85% or more, and particularly preferably 95% or more. Furthermore, the average value of n is within the range of 0 to 5, preferably within the range of 0 to 2, more preferably within the range of 0 to 1, and particularly preferably within the range of 0 to 0.5. Within this range, it is easier to suppress the excessive increase in molecular weight due to the addition of acid dianhydrides.

[0041] The above epoxy resin is reacted with (meth)acrylic acid to produce an epoxy (meth)acrylate resin having polymerizable unsaturated groups. Epoxy resin and (meth)acrylic acid can be reacted by known methods. For example, equimolar (meth)acrylic acid is used for 1 mole of epoxy groups of the epoxy resin, but to react all epoxy groups with (meth)acrylic acid, a slightly excess amount of (meth)acrylic acid may be used compared to the equimolar ratio of epoxy groups to calcium groups. This reaction yields an epoxy (meth)acrylate resin in which the glycidyl group in general formula (5) is replaced with a group represented by the following formula (6).

[0042] [ka] Here, R 3 This is equivalent to the definition in the general formula (1) above.

[0043] The solvent, catalyst, and other reaction conditions used in this reaction are not particularly limited. For example, it is preferable to use a solvent that does not contain hydroxyl groups 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, and ketone solvents such as cyclohexanone and diisobutyl ketone. Examples of the catalysts mentioned above include ammonium salts such as tetraethylammonium bromide and triethylbenzylammonium chloride, as well as known catalysts such as phosphines like triphenylphosphine and tris(2,6-dimethoxyphenyl)phosphine.

[0044] This reaction yields an epoxy (meth)acrylate resin represented by general formula (1). This epoxy (meth)acrylate resin contains by-products derived from side reactions and by-products contained in the synthesis of the raw materials. These may be purified and removed before use, or some by-products may remain as long as they do not impair the quality or use of the product.

[0045] By reacting the above epoxy (meth)acrylate resin with carboxylic acids, a polymerizable unsaturated group-containing alkali-soluble resin can be obtained. As carboxylic acids, (a) dicarboxylic acids or tricarboxylic acids and (b) tetracarboxylic acids are used. Dicarboxylic acids or tricarboxylic acids may be dicarboxylic acids or tricarboxylic acids, or their acid anhydrides, but acid anhydrides are suitable in terms of reactivity. Similarly, as tetracarboxylic acids, tetracarboxylic acids may be tetracarboxylic acids or their acid dianhydrides, but acid dianhydrides are suitable in terms of reactivity.

[0046] The above (a) examples of dicarboxylic acids, tricarboxylic acids, or acid anhydrides include saturated chain hydrocarbon dicarboxylic acids or tricarboxylic acids or acid anhydrides thereof, saturated cyclic hydrocarbon dicarboxylic acids or tricarboxylic acids or acid anhydrides thereof, unsaturated hydrocarbon dicarboxylic acids or tricarboxylic acids or acid anhydrides thereof, aromatic hydrocarbon dicarboxylic acids or tricarboxylic acids or acid anhydrides thereof, etc. Each hydrocarbon residue (structure excluding the carboxyl group) of these dicarboxylic acids or tricarboxylic acids or acid anhydrides may be further substituted with substituents such as alkyl groups, cycloalkyl groups, or aromatic groups.

[0047] Examples of saturated-chain hydrocarbon dicarboxylic acids 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 acids or tricarboxylic acids include hexahydrophthalic acid, cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, norbornanedicarboxylic acid, and hexahydrotrimellitic acid. Examples of unsaturated hydrocarbon dicarboxylic acids or tricarboxylic acids include maleic acid, itaconic acid, tetrahydrophthalic acid, methylendomethylenetetrahydrophthalic acid, and chloridenic acid. Examples of aromatic hydrocarbon dicarboxylic acids or tricarboxylic acids include phthalic acid and trimellitic acid. Acid anhydrides of these dicarboxylic acids or tricarboxylic acids can also be used. Of these, succinic acid, itaconic acid, tetrahydrophthalic acid, hexahydrotrimellitic acid, phthalic acid, and trimellitic acid or their anhydrides are preferred, and succinic acid, itaconic acid, and tetrahydrophthalic acid or their acid anhydrides are more preferred.

[0048] Examples of (b) tetracarboxylic acids or their dianhydrides mentioned above include chain-type hydrocarbon tetracarboxylic acids or their dianhydrides, alicyclic tetracarboxylic acids or their dianhydrides, and aromatic polycarboxylic acids or their dianhydrides. Each hydrocarbon residue (the structure excluding the carboxyl group) of these tetracarboxylic acids or their dianhydrides may be further substituted with substituents such as alkyl groups, cycloalkyl groups, or aromatic groups.

[0049] Specific examples of tetracarboxylic acids include, among others, chain-type hydrocarbon tetracarboxylic acids, butanetetracarboxylic acid, pentanetetracarboxylic acid, and hexanetetracarboxylic acid. Examples of alicyclic tetracarboxylic acids include cyclobutanetetracarboxylic acid, cyclopentanetetracarboxylic acid, cyclohexanetetracarboxylic acid, cycloheptanetetracarboxylic acid, and norbornanetetracarboxylic acid. Examples of aromatic polycarboxylic acids include pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, and biphenyl ethertetracarboxylic acid. Acidic dianhydrides of these tetracarboxylic acid compounds can also be used.

[0050] The molar ratio (a) / (b) of (a) carboxyl groups of dicarboxylic acid, tricarboxylic acid, or their acid anhydrides (calculated as 2 moles of carboxyl groups per acid anhydride) used in the above reaction, and (b) carboxyl groups of tetracarboxylic acid or its dianhydride (calculated as 2 moles of carboxyl groups per acid anhydride), is preferably 0.01 to 0.5, more preferably 0.02 to 0.3, and even more preferably 0.03 or more and less than 0.1. If the molar ratio (a) / (b) is within the above range, it becomes easier to obtain the optimal molecular weight for a photosensitive resin composition with good photopatternability. Note that the smaller the molar ratio (a) / (b), the greater the alkali solubility and the greater the molecular weight tends to be.

[0051] Regarding the reaction ratio between the epoxy (meth)acrylate resin (c) containing the polymerizable unsaturated group described above and the carboxylic acid components (a) and (b), it is preferable to quantitatively react the components (c):(a):(b) so that the terminal end of the compound becomes a carboxyl group, with each component (c):(a):(b) = 1:0.2~1.0:0.01~1.0, preferably 1:0.2~0.4:0.4~0.8. In this case, it is preferable to quantitatively react the components so that the molar ratio of the total amount of acid components to the epoxy (meth)acrylate resin is (c) / [(a) / 2+(b)] = 0.5~1.0. If this molar ratio is less than 0.5, the terminal end of the alkali-soluble resin becomes an acid anhydride, and the content of unreacted acid dianhydrides increases, raising concerns about a decrease in the long-term stability of the alkali-soluble resin composition. On the other hand, if the molar ratio exceeds 1.0, the content of hydroxyl group-containing compounds containing unreacted polymerizable unsaturated groups increases, raising concerns about a decrease in the long-term stability of the alkali-soluble resin composition. The molar ratios of components (a), (b), and (c) can be arbitrarily changed within the above range for the purpose of adjusting the acid value and molecular weight of the alkali-soluble resin. Another preferred embodiment from a different perspective is to quantitatively react the epoxy (meth)acrylate resin (c) with the hydroxyl group such that the total amount of carboxyl groups of the carboxylic acid component [(a) + (b)] (calculated as 2 moles of carboxyl groups for the acid anhydride group) is 0.1 to 1.0 moles, preferably 0.5 to 1.0 moles.

[0052] The above reactions with (a) dicarboxylic acids, tricarboxylic acids or their acid anhydrides, and (b) tetracarboxylic acids or their acid dianhydrides can be carried out by heating and stirring at 90-130°C in the presence of a catalyst such as triethylamine, tetraethylammonium bromide, and triphenylphosphine.

[0053] The alkali-soluble resin containing polymerizable unsaturated groups produced by the manufacturing method described above preferably has an acid value of 30 to 200 mgKOH / g, and more preferably 50 to 150 mgKOH / g. If the oxidation is less than 30 mgKOH / g, residue tends to remain during alkaline development, and if it exceeds 200 mgKOH / g, the penetration of the alkaline developer becomes too fast, which may cause peeling during development.

[0054] In the manufacturing method described above, from the viewpoint of lowering the viscosity of the polymerizable unsaturated group-containing alkali-soluble resin produced, it is preferable that the content of n=0 in general formula (5) be 50% or more, more preferably 70% or more, even more preferably 85% or more, and particularly preferably 95% or more. Furthermore, the average value of n is within the range of 0 to 5, preferably within the range of 0 to 2, more preferably within the range of 0 to 1, and particularly preferably within the range of 0 to 0.5.

[0055] Furthermore, the alkali-soluble resin containing polymerizable unsaturated groups produced by the manufacturing method described above preferably has a hydrolyzable halogen content of 0.2% by mass or less. When the hydrolyzable halogen content is 0.2% by mass or less, inhibition of the curing reaction by hydrolyzable halogens is less likely to occur, and the physical properties of the cured product, especially the insulation reliability, are less likely to deteriorate, making it preferable for use in the electrical and electronic fields. The hydrolyzable halogen content is preferably 0.1% by mass or less, and more preferably 0.05% by mass or less.

[0056] In the manufacturing method described above, for example, when n=0 in general formula (5), an epoxy (meth)acrylate resin represented by general formula (1) is obtained, and furthermore, a polymerizable unsaturated group-containing alkali-available resin having the structure represented by general formula (2) is produced. The polymerizable unsaturated group-containing alkali-available resin of the present invention may not only be a resin with the structure represented by general formula (2), but may also be a resin containing resins with different degrees of polymerization produced at each stage of the above manufacturing method, or resins derived therefrom. In general formula (2), m is a number from 1 to 20, but the average value is preferably in the range of 1.5 to 10, and more preferably in the range of 2 to 5.

[0057] Incidentally, the epoxy resin obtained by the above manufacturing method may also contain components with 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 may become difficult to control the increase in molecular weight through reaction with anhydrides, especially with (b) tetracarboxylic acid or its dianhydride. 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 of various molecular weights, and L in the following formula (7a) 3 L of other molecules 1 or L 2 Because they bond as one of the above general formulas (2), polymerization proceeds in a structure other than that of the above general formula (2). However, as long as the content of the n=0 form of the epoxy resin is within the range described above, the presence of these components does not affect the effects of the present invention.

[0058] [ka] Here, R 3 This is equivalent to the definition in the general formula (1) above, X and Z are equivalent to the definitions in the general formula (2) above, n is equivalent to the definition in the general formula (5) above, L 1 and L 2 Each of these is independently a hydrogen atom, one of the elements in formula (7a) above, or one of the elements in formula (3), but not all of them are hydrogen atoms. Formula (3) is the same as the one in formula (2) above. L 3 L of other molecules 1 or L 2 They are joined together as follows.

[0059] [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) Photopolymerization initiator, and (D) Solvent

[0060] (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, 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, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, glycerol This includes (meth)acrylic acid esters such as methyl(meth)acrylate, sorbitol penta(meth)acrylate, dipentaerythritol penta(meth)acrylate, or dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, alkylene oxide-modified hexa(meth)acrylate of phosphazene, and caprolactone-modified dipentaerythritol hexa(meth)acrylate, polyhydric alcohols such as pentaerythritol and dipentaerythritol, vinyl benzyl ether compounds of polyhydric phenols such as phenol novolac, and addition polymers of divinyl compounds such as divinylbenzene. When it is necessary to form crosslinked structures between molecules of alkali-soluble resins containing polymerizable unsaturated groups, it is more preferable to use photopolymerizable monomers having three or more polymerizable unsaturated groups. These photopolymerizable monomers may be used alone or in combination of two or more. Furthermore, (B) photopolymerizable monomers having at least two polymerizable unsaturated groups do not have free carboxyl groups.

[0061] The mixing ratio of component (B) is preferably 5 to 400 parts by mass, and more preferably 10 to 150 parts by mass, per 100 parts by mass of component (A). If the mixing ratio of component (B) is greater than 400 parts by mass per 100 parts by mass of component (A), the cured product after photocuring becomes brittle, and the acid value of the coating film in the unexposed areas is low, resulting in reduced solubility in the alkaline developer and problems such as jagged and unsharp pattern edges. On the other hand, if the mixing 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 is low, resulting in insufficient formation of a cross-linked structure. Furthermore, the acid value of the resin component is high, resulting in high solubility in the alkaline developer in the exposed areas, which may cause problems such as the formed pattern becoming thinner than the target line width or the pattern being prone to gaps.

[0062] (C) Examples of photopolymerization initiators include acetophenones such as acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, and pt-butylacetophenone; benzophenones such as benzophenone, 2-chlorobenzophenone, and p,p'-bisdimethylaminobenzophenone; and benzoin such as benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether. Ethers, biimidazole compounds including 2-(o-chlorophenyl)-4,5-phenylbiimidazole, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)biimidazole, 2-(o-fluorophenyl)-4,5-diphenylbiimidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, and 2,4,5-triarylbiimidazole, 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, and 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazo Halomethyldiazole compounds including 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4-oxadiazole, 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl)-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 Halomethyl-s-triazine compounds including 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-trimethoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 1,2-octanedione, 1-[4-(phenylthio)phenyl]-,2-(O-benzoyl oxime), 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-carbazole-3 -yl]-,1-(0-acetyloxime),methanone,(9-ethyl-6-nitro-9H-carbazole-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-9 This includes O-acyloxime compounds such as H-fluoren-2-yl]-,1-(O-acetyloxime) and ethanone, 1-(-9,9-dibutyl-7-nitro-9H-fluoren-2-yl)-,1-O-acetyloxime; sulfur compounds such as benzyldimethylketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, and 2-isopropylthioxanthone; anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, and 2,3-diphenylanthraquinone; organic peroxides such as azobisisobutylnitrile, benzoyl peroxide, and cumene peroxide; and thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, and 2-mercaptobenzothiazole. These photopolymerization initiators may be used individually or in combination of two or more. In this invention, the term "photopolymerization initiator" includes sensitizers.

[0063] Furthermore, (C) as a photopolymerization initiator, compounds that do not act as photopolymerization initiators or sensitizers on their own, but can increase the ability of photopolymerization initiators or sensitizers 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.

[0064] The proportion of component (C) is preferably 0.1 to 30 parts by mass, and more preferably 1 to 25 parts by mass, based on a total of 100 parts by mass of components (A) and (B). If the proportion of component (C) is less than 0.1 parts by mass, the photopolymerization rate will be slow and the sensitivity will decrease. On the other hand, if it exceeds 30 parts by mass, the sensitivity will be too strong, causing the pattern line width to become thicker than that of the pattern mask, making it impossible to reproduce the line width faithful to the mask, or causing the pattern edges to be jagged and not sharp.

[0065] (D) Examples of solvents include alcohols such as 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 such as α- or β-terpineol; ketones such as acetone, methyl ethyl ketone, cyclohexanone, and N-methyl-2-pyrrolidone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, ethyl cellosolve, carbitol monoethyl ether, and dipropylene glycoside. This includes glycol ethers such as ethyl acetate monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether, as well as esters such as 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, and propylene glycol monoethyl ether acetate. These solvents may be used individually or in combination of two or more to satisfy properties such as applicability.

[0066] Furthermore, the above photosensitive resin composition may contain additives such as curing accelerators, thermal polymerization inhibitors and antioxidants, plasticizers, fillers, leveling agents, defoamers, coupling agents, surfactants, and colorants, as needed. As curing accelerators, for example, known compounds that are commonly used in epoxy resins as curing accelerators, curing catalysts, and latent curing agents can be used, and include tertiary amines, quaternary ammonium salts, tertiary phosphines, quaternary phosphonium salts, borate esters, Lewis acids, organometallic compounds, imidazoles, and diazabicyclo compounds. Examples of thermal polymerization inhibitors and antioxidants include hydroquinone, hydroquinone monomethyl ether, pyrogallol, t-butylcatechol, phenothiazine, hindered phenol compounds, and phosphorus-based heat stabilizers. Examples of plasticizers include dibutyl phthalate, dioctyl phthalate, and tricresyl phosphate. Examples of fillers include glass fiber, silica, mica, and alumina. Examples of leveling agents and defoaming agents include silicone-based, fluorine-based, and acrylic compounds. Examples of coupling agents include silane coupling agents such as vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-(glycidyloxy)propyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-(phenylamino)propyltrimethoxysilane, and 3-ureidopropyltriethoxysilane. Examples of surfactants include fluorine-based surfactants and silicone-based surfactants. Known pigments and dyes can be used without limitation as colorants.

[0067] The above photosensitive resin composition may also be used in addition to (A) to (D) an epoxy resin having two or more epoxy groups (E). Examples of such epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, biphenyl type epoxy resins, bisphenol fluorene type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, polymers containing polyhydric alcohol glycidyl ethers, polyhydric carboxylic acid glycidyl esters, (meth)acrylate glycidyl as a unit, alicyclic epoxy resins represented by 3,4-epoxycyclohexanecarboxylic acid [(3,4-epoxycyclohexyl)methyl], 1,2-epoxy-4-(2-oxyranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol (e.g., "EHPE3150", manufactured by Daicel Corporation), phenyl glycidyl ethers, p-butylphenol glycidyl ethers, triglycidyl isocyanurates, diglycidyl isocyanurates, epoxidized polybutadiene (e.g., "NISSO-PB·JP-100", manufactured by Nippon Soda Co., Ltd.), and epoxy resins having a silicone backbone. These components are preferably compounds with an epoxy equivalent of 100 to 300 g / eq and a number-average molecular weight of 100 to 5000. Component (E) may be a single compound or two or more compounds may be used in combination. If it is necessary to increase the crosslinking density of the alkali-soluble resin, a compound having at least two epoxy groups is preferred.

[0068] When using epoxy resin (E), the amount added is preferably 10 to 40 parts by mass per 100 parts by mass of the total of components (A) and (B). One purpose of adding epoxy resin is to reduce the amount of carboxyl groups remaining after the cured film is formed following patterning, in order to improve the reliability of the cured film. In this case, if the amount of epoxy resin added is less than 10 parts by mass, it may not be possible to ensure the moisture resistance reliability when used as an insulating film. Also, if the amount of epoxy resin added is more than 40 parts by mass, the amount of photosensitive groups in the resin component of the photosensitive resin composition may decrease, and sufficient sensitivity for patterning may not be obtained.

[0069] The above photosensitive resin composition contains components (A) to (D) or components (A) to (E) as its main components. It is desirable that components (A) to (C) and (E) together constitute 70% by mass, preferably 80% by mass or more, of the solid content. The amount of solvent (D) varies depending on the target viscosity, but it is preferable that it be contained in the photosensitive resin composition in the range of 60 to 90% by mass.

[0070] [Cured product] The above photosensitive resin composition can be cured by, for example, applying it to a substrate, drying it, and irradiating it with light (including ultraviolet light and radiation) to cure it. In this case, by using a photomask or the like to create areas that are exposed to light and areas that are not, only the areas exposed to light can be cured, and the other areas can be dissolved with an alkaline solution to obtain a cured product (coating) with a desired pattern.

[0071] Specifically, when applying the photosensitive resin composition to a substrate, any known method can be used, such as the solution immersion method, the spray method, the use of a roller coater, land coater, slit coater, or spinner.

[0072] By these methods, a photosensitive resin composition is applied to the desired thickness, and then the solvent is removed (pre-baked) to form a film. Pre-baking is performed by heating in an oven or hot plate, vacuum drying, or a combination of these. The heating temperature and time during pre-baking are appropriately selected depending on the solvent used, for example, at a temperature of 80-120°C for 1-10 minutes.

[0073] Examples of radiation used for exposure include visible light, ultraviolet light, far ultraviolet light, electron beams, and X-rays, but radiation with a wavelength in the range of 250 to 450 nm is preferred.

[0074] Alkaline development can be carried out using aqueous solutions of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, and tetramethylammonium hydroxide as the developer. These developers are selected according to the characteristics of the resin layer, but surfactants may be added as needed. Development is preferably carried out at a temperature of 20 to 35°C. Fine images can be precisely formed by using commercially available developing machines or ultrasonic cleaners. After alkaline development, the image is usually washed with water. Examples of development methods include shower development, spray development, dip development, and paddle development.

[0075] After development in this manner, heat treatment (post-bake) is performed at a temperature of 180-250°C for 20-100 minutes. This post-bake is performed to improve the adhesion between the patterned coating and the substrate, among other purposes. Post-bake is carried out by heating using an oven or hot plate, similar to pre-bake.

[0076] Subsequently, polymerization or curing (sometimes referred to collectively 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.

[0077] The above-mentioned cured product can be used in resist layers such as solder resist layers, plating resist layers, and etching resist layers; interlayer insulating layers for multilayer printed circuit boards; films for gas barriers; encapsulants for semiconductor light-emitting elements such as lenses and light-emitting diodes (LEDs); topcoats for paints and inks; hardcoats for plastics; and anti-corrosion films for metals. [Examples]

[0078] The embodiments of the present invention will be specifically described below based on examples and comparative examples, but the present invention is not limited to these. In the examples, unless otherwise specified, "parts" refers to parts by mass, and "%" refers to mass percent. Furthermore, unless otherwise specified, the evaluation of the resin in the synthesis examples was carried out as follows.

[0079] [Solid content concentration] One g of the resin solution, photosensitive resin composition, etc. obtained in the synthesis example (and comparative synthesis example) was impregnated into a glass filter [mass: W0 (g)] and weighed [W1 (g)]. After heating at 160°C for 2 hours, the mass [W2 (g)] was obtained and the following formula was used to determine the mass. Solid content concentration (mass%) = 100 × (W2-W0) / (W1-W0)

[0080] [Acid value] The resin solution was dissolved in dioxane and titrated with a 0.1N KOH aqueous solution using a potentiometric titrator (COM-1600, manufactured by Hiranuma Sangyo Co., Ltd.). The amount of KOH required per gram of solid content was defined as the acid value.

[0081] [Molecular weight] The weight-average molecular weight (Mw) was calculated by gel permulation chromatography (GPC) (HLC-8220GPC manufactured by Tosoh Corporation, solvent: tetrahydrofuran, columns: TSKgelSuperH-2000 (2) + TSKgelSuperH-3000 (1) + TSKgelSuperH-4000 (1) + TSKgelSuper-H5000 (1) (manufactured by Tosoh Corporation), temperature: 40°C, rate: 0.6 mL / min), and the value was determined as a standard polystyrene (PS-oligomeric kit manufactured by Tosoh Corporation).

[0082] [IR] A Fourier transform infrared spectrophotometer (Perkin Elmer Precisely, Spectrum One FT-IR Spectrometer 1760X) was used, with a KRS-5 cell. The sample, dissolved in THF, was coated onto the cell, dried, and then measured at wavenumbers of 650-4000 cm⁻¹. -1 The absorbance was measured.

[0083] [ESI-MS] Mass spectrometry was performed using a mass spectrometer (Shimadzu Corporation, LCMS-2020) with acetonitrile and water as the mobile phases, by measuring the sample dissolved in acetonitrile.

[0084] Synthesis Example 1 In a reaction apparatus consisting of a glass separable flask equipped with a stirrer, thermometer, nitrogen blowing tube, dropping funnel, and condenser, 970 parts of 2,6-xylenol and 14.5 parts of 47% BF3 ether complex were charged and heated to 70°C with stirring. While maintaining the same temperature, 300 parts of dicyclopentadiene (0.29 molars relative to 2,6-xylenol) were added dropwise over 2 hours. The reaction was further carried out at a temperature of 125-135°C for 6 hours, and 2.3 parts of calcium hydroxide were added. Then, 4.6 parts of 10% oxalic acid aqueous solution were added. After that, the mixture was heated to 160°C to dehydrate it, and then heated to 200°C under reduced pressure of 5 mmHg to evaporate and remove unreacted starting materials. 1000 parts of MIBK were added to dissolve the product, and 400 parts of 80°C warm water were added for washing, and the lower layer of water was separated and removed. Subsequently, MIBK was evaporated and removed by heating to 160°C under reduced pressure of 5 mmHg, yielding 540 parts of a reddish-brown phenolic resin according to general formula (4). The hydroxyl group equivalent was 213, the softening point was 71°C, and the absorption ratio (A) was determined by FT-IR measurement. 3040 / A 1210 The ratio was 0.11. Mass spectra measured by ESI-MS (negative) confirmed M-=253, 375, 507, and 629. Based on these FT-IR absorption ratios and ESI-MS measurements, at least the R ratio of general formula (4) was confirmed. 2 The introduction of a dicyclopentenyl group can be confirmed.

[0085] In a reaction apparatus similar to that used in Synthesis Example 1, 250 parts of the obtained phenolic resin, 544 parts of epichlorohydrin, and 163 parts of diethylene glycol dimethyl ether were added and heated to 65°C. Under reduced pressure of 125 mmHg, 108 parts of 49% sodium hydroxide aqueous solution were added dropwise over 4 hours while maintaining a temperature of 63-67°C. During this time, the epichlorohydrin was azeotropically mixed with water, and the resulting water was sequentially removed from the system. After the reaction was complete, the epichlorohydrin was recovered under conditions of 5 mmHg and 180°C, and the product was dissolved by adding 948 parts of MIBK. Then, 263 parts of water were added to dissolve the by-product sodium chloride, and the mixture was allowed to stand to separate and remove the lower layer of saline solution. After neutralization with phosphoric acid aqueous solution, the resin solution was washed with water until the rinse solution was neutral, and then filtered. Under reduced pressure of 5 mmHg, the mixture was heated to 180°C to remove MIBK by distillation, yielding 298 parts of a reddish-brown transparent 2,6-xylenol-dicyclopentadiene type epoxy resin according to general formula (5). The epoxy equivalent was 282, the total chlorine content was 980 ppm, and the resin was semi-solid at room temperature. The average value of n in general formula (5) was 0.05.

[0086] In a reaction apparatus similar to that used in Synthesis Example 1, 282 parts of the obtained 2,6-xylenol-dicyclopentadiene type epoxy resin were dissolved in 63 parts of PGMEA. Further addition of 72 parts of acrylic acid, 3.5 parts of triphenylphosphine, and 0.1 parts of hydroquinone was added, and the reaction was carried out at 110°C for 8 hours while blowing in air. Then, 293 parts of PGMEA were added to obtain a PGMEA solution of epoxy acrylate resin (DPXLEA). The solid content of the obtained resin solution was 50%. GPC measurement of the obtained DPXLEA using the method described above revealed that the content of n=0 was 95 area%, and the total content of n=1 and n=2 was 5 area%.

[0087] Furthermore, the abbreviations used in the examples and comparative examples are as follows: DPXLEA: Epoxy acrylate resin obtained in the above synthesis example 1. BPAEA: A reaction product of bisphenol A type epoxy resin (epoxy equivalent 182) and acrylic acid (an isostoichiometric reaction product of epoxy groups and carboxyl groups). BPDA: 3,3',4,4'-biphenyltetracarboxylic acid dianhydride THPA:1,2,3,6-tetrahydrophthalic anhydride TEAB: Tetraethylammonium bromide MIBK: Methyl isobutyl ketone PGMEA: Propylene glycol monomethyl ether acetate

[0088] Example 1 In a reaction vessel equipped with a stirrer, temperature control device, reflux condenser, and air introduction device, 450 parts of DPXLEA's 50% PGMEA solution, 49 parts of BPDA, 25 parts of THPA, 0.69 parts of TEAB, and 20 parts of PGMEA were charged and stirred under heating at 120-125°C for 6 hours to obtain an alkali-soluble resin (A1). The obtained resin had a solid content concentration of 55%, an acid value (based on solid content) of 92 mgKOH / g, and a molecular weight (Mw) of 3600.

[0089] Comparative Example 1 In 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. Next, 61.8 parts of isophorone diisocyanate were added dropwise, paying attention to the temperature in the flask. After the addition was complete, the mixture was stirred for 6 hours under heating at 75-80°C. Furthermore, 21 parts of THPA were charged, and the mixture was stirred for 6 hours under heating at 90-95°C to obtain an alkali-soluble resin solution (HA1). The solid content concentration of the obtained resin was 66.5%, the acid value (based on solid content) was 38.4 mgKOH / g, and the molecular weight (Mw) was 12220.

[0090] Next, the present invention will be specifically described based on examples and comparative examples relating to photosensitive resin compositions and cured products, but the present invention is not limited to these. Hereinafter, the raw materials and abbreviations used in the following examples and comparative examples are as follows.

[0091] A1: Alkali-soluble resin obtained in Example 1 above HA1: Alkali-soluble resin obtained in Comparative Example 1 above 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 (BASF) C2: 4,4'-Bis(dimethylamino)benzophenone (Michler's ketone) D: Propylene glycol monomethyl ether acetate E: Cresol novolac type epoxy resin (manufactured by Nippon Steel Chemical & Material Co., Ltd., YDCN-700-3, epoxy equivalent 203 g / eq., softening point 73°C)

[0092] The above-mentioned components were blended in the proportions shown in Table 1 to prepare the photosensitive resin compositions of Example 2 and Comparative Examples 2-3. All values ​​in Table 1 represent parts by mass.

[0093] [Table 1]

[0094] The photosensitive resin compositions shown in Table 1 were applied to a 125 mm × 125 mm glass substrate using a spin coater to a post-baking film thickness of 30 μm, and then pre-baked at 110°C for 5 minutes to create a coated plate. Subsequently, a photomask for pattern formation was used to heat the plate at 500 W / cm². 2 The exposed areas were irradiated with ultraviolet light at a wavelength of 365 nm using a high-pressure mercury lamp to perform a photocuring reaction. Next, the exposed coated plate was developed using a 0.8% tetramethylammonium hydroxide (TMAH) aqueous solution with a shower development at 23°C for an additional 30 seconds from the time when the pattern began to appear, and then sprayed with water to remove the unexposed areas of the coating. After that, the plate was heat-cured using a hot air dryer at 230°C for 30 minutes to obtain the cured films according to Example 2 and Comparative Examples 2-3.

[0095] The cured films obtained under the above conditions were evaluated as follows. For the preparation of cured films for the film thickness test, alkali resistance test, and acid resistance test, full-surface exposure without a photomask was followed by development, washing, and heat curing.

[0096] (film thickness) A portion of the coated film was scraped off, and the step shape was measured using a stylus-type step shape measuring device (product name P-10, manufactured by KLA-Tencor Co., Ltd.).

[0097] (Adhesion) At least 100 cross-cuts were made on a glass substrate with a hardened film, creating a grid pattern. Then, a peeling test was performed using cellophane tape, and the grid pattern was visually evaluated. ◎: No peeling observed at all ○: Slight peeling of the paint film is visible. △: Some areas of the paint film show signs of peeling. ×: Products where the film almost completely peels off.

[0098] (Alkali resistance) A glass substrate with a cured film was immersed in a solution of 30 parts by mass of 2-aminoethanol and 70 parts by mass of glycol ether, maintained at 80°C. After 10 minutes, it was removed, washed with pure water, and dried to prepare a chemically immersed sample, and its adhesion was evaluated.

[0099] (Acid resistance) Glass substrates with a hardened film were immersed in a solution of aqua regia (hydrochloric acid:nitric acid = 7:3) maintained at 50°C. After 10 minutes, they were removed, washed with pure water, dried, and chemically immersed samples were prepared for evaluation of adhesion.

[0100] (Bending test) The photosensitive resin compositions shown in Table 1 were applied using a spin coater to a glass substrate with a 125 mm x 125 mm release film attached, so that the post-baking film thickness was 30 μm. A coated plate was then prepared by pre-baking at 110°C for 5 minutes. Subsequently, a photomask for pattern formation was used to heat the plate at 500 W / cm². 2The exposed areas were irradiated with ultraviolet light at a wavelength of 365 nm using a high-pressure mercury lamp to perform a photocuring reaction. Next, the exposed coated plate was developed using a 0.8% tetramethylammonium hydroxide (TMAH) aqueous solution in a shower development at 23°C for an additional 30 seconds from the time when the pattern began to appear, and then sprayed with water to remove the unexposed areas of the coating. After that, the coating was heat-cured using a hot air dryer at 230°C for 30 minutes, and the resulting pattern was peeled off the release film to obtain the films according to Example 2 and Comparative Examples 2-3.

[0101] The film obtained under the above conditions was folded in half, and then spread open with the top of the fold facing upwards. This test was repeated, and the number of times cracks or fractures were observed was used for evaluation.

[0102] [Table 2]

[0103] The results from Example 2 and Comparative Examples 2-3 show that using the photosensitive resin composition containing the polymerizable unsaturated group-containing alkali-soluble resin of the present invention enables patterning with excellent resolution by alkaline development, excellent chemical resistance, and the production of a cured film with excellent reliability, such as resistance to seam folding.

Claims

1. Represented by the general formula (1) below, this represents the 3040 cm² derived from the C-H stretching vibration of the olefin moiety of the dicyclopentadiene skeleton in the dicyclopentenyl group in the FT-IR measurement method. －１ Peak height of nearby peaks (A ３０４０ ) and 1210 cm² originating from C-O stretching vibrations in the phenol nucleus (phenol residues) －１ Peak height of nearby peaks (A １２１０ A is the ratio of ) ３０４０ / A １２１０ A method for producing a polymerizable unsaturated group-containing alkali-soluble resin, characterized by reacting an epoxy (meth)acrylate resin having a ratio of 0.11 or higher with a dicarboxylic acid, a tricarboxylic acid, or an acid anhydride thereof, and a tetracarboxylic acid or its dianhydride. 【Chemistry 1】 Here, R １ These independently represent an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group. R ２ Each element independently represents either a hydrogen atom or a dicyclopentenyl group, and one or more of them are dicyclopentenyl groups. R ３ represents a hydrogen atom or a methyl group.

2. It has a structure represented by general formula (2), and in the FT-IR measurement method, it exhibits a 3040 cm² vibration originating from the C-H stretching vibration of the olefin moiety of the dicyclopentadiene skeleton in the dicyclopentenyl group. －１ Peak height of nearby peaks (A ３０４０ ) and 1210 cm² originating from C-O stretching vibrations in the phenol nucleus (phenol residues) －１ Peak height of nearby peaks (A １２１０ A is the ratio of ) ３０４０ / A １２１０ A polymerizable unsaturated group-containing alkali-soluble resin having a ratio of 0.11 or higher. 【Chemistry 2】 Here, X represents a tetravalent carboxylic acid residue, Y represents a carboxyl group-containing group or hydrogen atom represented by formula (3), and if 1 or more are carboxyl group-containing groups represented by formula (3), Z represents the structure shown in equation (2a), m is a number whose average value is between 1 and 20. R １ This represents an alkyl group having 1 to 8 carbon atoms, a phenyl group, or an allyl group. R ２ Each element independently represents either a hydrogen atom or a dicyclopentenyl group, and one or more of them are dicyclopentenyl groups. R ３ represents a hydrogen atom or a methyl group. M represents a p+1 valent carboxylic acid residue, where p is 1 or 2.

3. A photosensitive resin composition characterized by containing, as essential components, a polymerizable unsaturated group-containing alkali-soluble resin according to claim 2, a photopolymerizable monomer having at least two polymerizable unsaturated groups and being different from the alkali-soluble resin, a photopolymerization initiator, and a solvent.

4. The photosensitive resin composition according to claim 3, further comprising an epoxy resin having two or more epoxy groups.

5. The photosensitive resin composition according to claim 3 or 4, comprising 0.1 to 30 parts by mass of a photopolymerization initiator and 10 to 40 parts by mass of a solvent, per 100 parts by mass of a total of a polymerizable unsaturated group-containing alkali-soluble resin and a photopolymerizable monomer.

6. A cured product obtained by curing the photosensitive resin composition according to any one of claims 3 to 5.

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