JPH0562732B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a photosensitive resin composition. More specifically, the present invention relates to a photosensitive resin composition for forming a protective film that has excellent properties that can be used in printed wiring board production, metal precision processing, and the like.

(Prior Art) It is well known that a photosensitive resin composition is used to form a resist for plating or etching in the precision processing industry, for example, in the production of printed wiring boards. Recently, photosensitive resin compositions have also been used in the field of permanent masks such as electroless plating masks and solder masks.

Permanent masks are heat resistant, solvent resistant, chemical resistant,
Since excellent properties such as electrical properties and mechanical properties are required, there are a limited number of photosensitive resins that can be used. JP-A-52-117985, JP-A-54-1018, JP-A-53-56018 and the like disclose photosensitive resin compositions that can be used as permanent masks. However, these photosensitive resin compositions mainly contain a polymeric binder and a monomer and are not suitable for forming a thick protective film. In other words, since these photosensitive resin compositions use a polymeric binder with a high glass transition temperature, when forming a photosensitive layer, the photosensitive resin composition is first mixed with toluene, methyl ethyl ketone, or methylene chloride. The photosensitive layer must be formed by uniformly dissolving or dispersing it in an organic solvent such as, etc., followed by coating and drying.
Therefore, when the film becomes thick, air bubbles are likely to occur during drying and the resin tends to flow, making it difficult to form a uniform protective film.

Solvent-free photosensitive resin compositions that can be used as permanent masks have been proposed in Japanese Patent Publications No. 55-127097 and Japanese Patent Application Laid-Open No. 49-107048. but,
These liquid compositions are unsuitable for forming thick films and high-resolution protective films. In other words, these liquid compositions use epoxy acrylate, which has poor solubility, and therefore have poor developability. etc)
It is difficult to form thick films and high-resolution images with flame-retardant developers such as 1,1,1-trichloroethane, which are used in 1,1,1-trichloroethane, and the sensitivity is not necessarily sufficient.

(Problems to be Solved by the Invention) An object of the present invention is to eliminate the drawbacks of the prior art and form thick film, high resolution images using a flame retardant developer such as 1,1,1-trichloroethane. It is an object of the present invention to provide a photosensitive resin composition that can form a highly reliable solder mask with excellent heat resistance.

(Means for Solving the Problems) The present invention provides (a) an addition reaction between a compound having at least one epoxy group and an unsaturated carboxylic acid at an acid equivalent/epoxy equivalent ratio in the range of 0.1 to 0.98; To the unsaturated compound obtained by
A photopolymerizable prepolymer obtained by reacting in the range of ~1.2 (b) a photopolymerizable monomer and (c) a sensitizer and/or a sensitizer system that generates free radicals by actinic light. The present invention relates to a photosensitive resin composition.

The photosensitive resin composition of the present invention comprises, as an essential component (a), an addition reaction between a compound having at least one epoxy group and an unsaturated carboxylic acid at an acid equivalent/epoxy equivalent ratio of 0.1 to 0.98. In the unsaturated compound obtained, for the hydroxyl group of the unsaturated compound,
It contains a photopolymerizable prepolymer obtained by reacting isocyanate ethyl methacrylate at an isocyanate equivalent/hydroxyl group equivalent ratio of 0.1 to 1.2.

A compound having at least one epoxy group can have, in addition to the epoxy group, a functional group other than the epoxy group in the molecule, such as a hydroxyl group, an acrylic group, a methacryl group, an acrylic group, and the like.

Examples of the compound having at least one epoxy group include bisphenol A obtained by reacting bisphenol A and epichlorohydrin.
Type epoxy resin (e.g. Ciel Chemical Epicoat)
812, Epikote 828, Epicoat 1001, etc.) Brominated bisphenol A type epoxy resin (e.g. Epitote YDB-340, YDB-400, manufactured by Toto Kasei Co., Ltd.),
Bisphenol F type epoxy resin (e.g. Epotote YDF-170, YDF-190, manufactured by Toto Kasei Co., Ltd.),
Epoxy compounds obtained by adding alkylene oxide to bisphenol A and reacting with epichlorohydrin (for example, Epolite 3002 manufactured by Kyoeisha Yushi Co., Ltd.), hydrogenated bisphenol A type epoxy resin (for example, Santo ST manufactured by Toto Kasei Co., Ltd.) −1000,
ST-3000, etc.), glyoxal type epoxy resin (e.g. Epotote YDG-414 manufactured by Toto Kasei Co., Ltd.),
Glycidylamine type epoxy resin (e.g., Epotote YDM-120, YH-434, manufactured by Toto Kasei Co., Ltd.), orthocresol novolak type epoxy resin (e.g., EOCN102, manufactured by Nippon Kayaku Co., Ltd.), phenol novolak type epoxy resin (For example, manufactured by Toto Kasei Co., Ltd.
YDPN-638, etc.), brominated phenol novolak type epoxy resin (e.g. BREN manufactured by Nippon Kayaku Co., Ltd.)
etc.), alicyclic epoxy compounds (e.g. Chitsonox 221, Chitsonox 201, etc. manufactured by Chitso Corporation), glycidyl ether type epoxy resins obtained by the reaction of dicarboxylic acids such as phthalic acid with epichlorohydrin (e.g. manufactured by Showa Denko Corporation) Syodyne 508,
Syodyne 540, Syodyne 550, etc.), polybutadiene epoxides, glycidylamine type epoxy resins (Epicote 604, manufactured by Ciel Chemical Co., Ltd.),
Examples include trimethylolpropane polyglycidyl ether, glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, and the like.

As the unsaturated carboxylic acid, acrylic acid, methacrylic acid, β-furylacrylic acid, β-styrylacrylic acid, α-cyanocinnamic acid, cinnamic acid, etc. are used.

In the present invention, the addition reaction between a compound having at least one epoxy group and an unsaturated carboxylic acid is as shown in formula (), and the acid equivalent/
This is carried out by a conventional method at an epoxy equivalent ratio of 0.1 to 0.98. If the acid equivalent/epoxy equivalent ratio is less than 0.1, the photocured film is likely to swell during development treatment after image exposure. Acid equivalent/epoxy equivalent ratio is 0.98
If it exceeds this, adhesiveness, heat resistance, etc. will decrease.

The unsaturated compound of the present invention can be prepared using, for example, a tertiary amine such as triethylamine, tri-n-butylamine, or diethylcyclohexylamine as a catalyst, or a quaternary ammonium salt such as benzyltrimethylammonium chloride or benzyltriethylammonium chloride, or as a polymerization inhibitor. Hydroquinone, p-
It is obtained by stirring and reacting the unsaturated carboxylic acid and the compound having an epoxy group at 70 to 110°C using methoxyphenol or the like. In this reaction, methyl ethyl ketone, methyl cellosolve acetate, 1,1,1
- Organic solvents such as trichloroethane and photopolymerizable monomers such as polypropylene glycol diacrylate and ethyl carbitol acrylate can be used.

The reaction of isocyanate ethyl methacrylate to the unsaturated compound obtained by the addition reaction of a compound having an epoxy group and an unsaturated carboxylic acid as described above is as shown in the formula (), and the isocyanato ethyl methacrylate is The reaction of ethyl methacrylate is carried out in a conventional manner at an isocyanate equivalent/hydroxyl equivalent ratio of 0.1 to 1.2. Isocyanate equivalent/hydroxyl group equivalent ratio is 0.1
When the amount is less than 1, it becomes difficult to develop with a flame-retardant organic solvent such as 1,1,1-trichloroethane, and the photocurability also decreases. When the isocyanate equivalent/hydroxyl group equivalent ratio exceeds 1.2, gelation is likely to occur during the reaction, and properties such as heat resistance are also reduced. After the reaction, it is desirable to urethane and deactivate the remaining isocyanatoethyl methacrylate using an alcohol such as methanol, ethanol, 2-hydroxyethyl acrylate, etc. from the viewpoint of safety and improving storage stability.

As the isocyanate ethyl methacrylate, for example, one manufactured by Dow Chemical Company is used.

For example, the above-mentioned compound having at least one epoxy group is subjected to an addition reaction with an unsaturated carboxylic acid, and then a urethanization catalyst such as dibutyltin dilaurate or dibutyltin di-2-ethylhexoate is added to the product, and the above-mentioned compound is added with an unsaturated carboxylic acid. isocyanate ethyl methacrylate in the equivalent ratio range of 50~
A photopolymerizable prepolymer is obtained by stirring and reacting at 110°C. Under such reaction conditions, side reactions such as the reaction between urethane bonds and epoxy groups and thermal polymerization of unsaturated bonds can be prevented, and as a result, photopolymerizable prepolymers can be produced without forming gel-like substances. Obtainable.

In the present invention, particularly preferred photopolymerizable prepolymers include orthocresol novolac type epoxy resin/ocrylic acid/isocyanatoethyl methacrylate (acid equivalent/epoxy equivalent ratio 0.1 to
0.98, isocyanate equivalent/hydroxyl group equivalent ratio 0.1~
1.2) System reactant, orthocresol novolac type epoxy resin/methacrylic acid/isocyanatoethyl methacrylate (acid equivalent/epoxy equivalent ratio
0.1-0.98, isocyanate equivalent/hydroxyl equivalent ratio
0.1-1.2) system reactant, bisphenol A type epoxy resin/acrylic acid/isocyanatoethyl methacrylate (acid equivalent/epoxy equivalent ratio 0.1-0.98,
Isocyanate equivalent/hydroxyl group equivalent ratio 0.1-1.2) system reactant, bisphenol A type epoxy resin/methacrylic acid/isocyanate ethyl methacrylate (acid equivalent/epoxy equivalent ratio 0.1-0.98, isocyanate equivalent/hydroxyl group equivalent ratio 0.1-1.2 ) system reactants, etc.

The photosensitive resin composition of the present invention contains a photopolymerizable monomer as an essential component (b). As this photopolymerizable monomer, known ones are used.

Preferred photopolymerizable monomers include butoxyethyl acrylate, ethyl carbitol acrylate, methyl triglycol acrylate, tetrahydrofurfuryl methacrylate, 2-hydroxy-3-phenoxypropyl acrylate, lauryl acrylate, 2-hydroxyethyl acrylate, Monofunctional monomers such as 2-hydroxyethyl methacrylate, phenoxyethyl methacrylate, cyclohexyl acrylate, trimethylolpropane, trimethylolethane, pentaerythritol, dipentaerythritol,
1,3-butylene glycol, 1,4-butylene glycol, 1,5-pentadiol, polycaprolactone diol, polypropylene glycol, decamethylene glycol, glycerin, neopentyl glycol, 2,2-bis[4,4'(2
-Hydroxyethyl)phenyl]propane, ester of polyhydric alcohol such as tris(2-hydroxyethyl)isocyanuric acid and acrylic acid or methacrylic acid, phthalic anhydride-diethylene glycol-acrylic acid (1/2/2 molar ratio) ) condensate,
Examples include low-molecular polyester resins having an acryloyloxy group and/or methacryloyloxy group at the terminal, such as a trimethylolpropane-tetrahydrophthalic anhydride-acrylic acid (2/1/4 molar ratio) condensate. A reaction product of diol monoacrylate or diol monomethacrylate and diisocyanate, a reaction product of isocyanatoethyl methacrylate/water (2/1 molar ratio), etc., as described in Japanese Patent Publication No. 52-43092, etc., can also be used.

The photosensitive resin composition of the present invention contains as an essential component (c) a sensitizer and/or a sensitizer system that generates free radicals by actinic light.

As a sensitizer, substituted or unsubstituted polynuclear quinones, such as 2-ethylanthraquinone, 2-
t-butylanthraquinone, octamethylanthraquinone, 1,2-penzanthraquinone, 2,
3-diphenylanthraquinone, etc., ketoaldonyl compounds such as diacetylbenzyl, benzoyl,
α-ketaldonyl alcohols and ethers such as pivalone, α-hydrocarbon substituted aromatic acyloins such as α-phenyl-benzoin, α,α
- Aromatic ketones such as diethoxyacetophenone, benzophenone, 4,4'-bisdialkylaminobenzophenone, 2-methylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, 2 - Thioxanthone such as ethylthioxanthone is used, and these may be used alone or in combination.

As the sensitizer system, for example, a combination of 2,4,5-triallylimidazole dimer and 2-mercaptobenzoquinazole, leuco crystal violet, tris(4-diethylamino-2-methylphenyl)methane, etc. is used. It will be done. Also, additives which do not have photoinitiating properties by themselves but which, when used in combination with the above-mentioned substances, result in a sensitizer system with better photoinitiating performance as a whole, such as tertiary amines such as triethanolamine for benzophenone, etc. Isoamyl dimethylaminobenzoate, N-methyldietalamine, bisethylaminobenzophenone, etc. for amines and thioxanthones can also be used.

The photosensitive resin composition of the present invention comprises (a) 100 parts by weight of the above photopolymerizable prepolymer, (b) 1 to 400 parts by weight of the above photopolymerizable monomer, and (c) the above increaser. It is preferable to use the sensitizer and/or sensitizer system in a range of 0.1 to 30 parts by weight in order to form a solder mask with excellent resolution and soldering heat resistance.

Furthermore, the photosensitive resin composition of the present invention may contain other subsidiary components. As a secondary ingredient,
Examples include thermal polymerization inhibitors, dyes, pigments, polymer binders, fillers, coatability improvers, antifoaming agents, flame retardants, flame retardant aids, adhesion improvers, latent hardeners for epoxy resins, etc. .

The photosensitive resin composition of the present invention can be prepared by roll coating,
A photosensitive layer having a thickness of 10 to 200 μm can be easily formed on a substrate to be processed and protected by a conventional method such as a screen printing method or a flow coating method.

In addition, the formation of the photosensitive layer is described in Japanese Patent Publication No. 48-23284,
This can be carried out using a conventional coating device for liquid type photosensitive resins, as shown in Japanese Patent Application Laid-open Nos. 49-43701 and 46-39404.

Exposure and development of the photosensitive layer thus formed are carried out by conventional methods. That is, an ultra-high-pressure mercury lamp, a high-pressure mercury lamp, or the like is used as a light source, and imagewise exposure is performed through a negative mask. In order to prevent resin from adhering to the negative mask, it is also possible to interpose a transparent cover film such as polyethylene terephthalate film, polypropylene film, cellulose acetate film, or polycarbonate film between the negative mask and the photosensitive resin layer. As the cover film becomes thicker, the resolution tends to decrease, so it is desirable that the thickness be 25 μm or less.

It is also possible to expose the negative mask with a distance of about 0.3 mm from the photosensitive layer. After exposure, if a cover film remains, peel it off and then develop.

The type of developer used in the development process is not particularly limited as long as it does not damage the exposed areas and selectively elutes the unexposed areas. As the developer, for example, a halogenated hydrocarbon such as 1,1,1-trichloroethane is used. In addition, cleaning agents containing 1,1,1-trichloroethane as a main component, such as Three-One EX (manufactured by Toagosei Kagaku Co., Ltd.)
You can also use

The image-like protective film obtained by the above method has characteristics as a corrosion-resistant film for ordinary etching, plating, etc., but after development, it is exposed to active light and heat-treated at 80 to 200°C. By doing
Furthermore, the properties can be improved, and a permanent protective film satisfying the properties as a solder mask can be obtained. The order of exposure to active light and heat treatment may be in any order.

(Effects of the Invention) The protective coating obtained using the photosensitive resin composition of the present invention has sufficient resistance to organic solvents such as tricrene, methyl ethyl ketone, isopropyl alcohol, and toluene, and also to acidic or alkaline aqueous solutions. Furthermore, since it has excellent heat resistance and mechanical properties, it can be used as a corrosion-resistant film for etching, plating, etc., and as a permanent protective film for solder masks and the like. Furthermore, the film formed using the photosensitive resin composition of the present invention has excellent chemical and physical properties, and therefore can be used as an interlayer insulating layer of a multilayer printed wiring board,
It can also be used in photosensitive adhesives, paints, plastic reliefs, printing plate materials, metal precision processing materials, etc.

Further, by using the photosensitive resin composition of the present invention, it is possible to develop with a flame retardant developer such as 1,1,1-trichloroethane, and a solder mask with excellent resolution and heat resistance can be formed. Furthermore, it is possible to form a thick film solder mask using a photographic method.

(Example) Parts in the examples mean parts by weight.

Example 1 (a) Synthesis of photopolymerizable prepolymer A Bisphenol A type epoxy resin, Epicoat 828 (epoxy equivalent: 190) 380 parts Tripropylene glycol diacrylate
140 parts B Acrylic acid 93.6 parts Benzyltrimethylammonium chloride 0.4 parts p-methoxyphenol 0.6 parts C Isocyanatoethyl methacrylate 214 parts Dibutyltin dilaurate 0.1 parts D Methanol 5 parts Heated with thermometer, stirrer, cooling tube and dropper and one coolable reactor.
was added, and the temperature was raised to 100°C while stirring to uniformly dissolve. B was added dropwise to this over about 30 minutes while maintaining the reaction temperature at 100°C. After dropping B, 100
Stirring was continued at ℃ for about 20 hours to bring the acid value of the reaction system to 1 or less.

Then reduce the temperature to 60℃ and reduce the reaction temperature to 60℃
C was uniformly added dropwise over a period of about 3 hours while maintaining the temperature. After dropping C, gradually lower the reaction temperature over about 5 hours.
After raising the temperature to 80℃, lower the temperature to 60℃, and
was added, and stirring was continued for about 1 hour. In this way, a mixture () containing 82% by weight of a photopolymerizable prepolymer based on bisphenol A type epoxy resin/acrylic acid/isocyanate ethyl methacrylate (acid equivalent/epoxy equivalent ratio = 0.65, isocyanate equivalent/hydroxyl group equivalent ratio = 1.06) was prepared. Obtained.

(b) Preparation of photosensitive resin composition 120 parts of the photopolymerizable prepolymer-containing mixture () obtained in (a) (99.6 parts of photopolymerizable prepolymer, photopolymerizable monomer, 20.1 parts of tripropylene glycol diacrylate, Other 0.3 parts) A photosensitive resin composition of the present invention was prepared by mixing 4 parts of 2,4-diethylthioxanthone, 5 parts of isobutyl dimethylaminobenzoate, and 0.01 part of Victoria Pure Blue.

(c) Formation of a cured film The photosensitive resin composition obtained in (b) was applied onto a copper-clad laminate to form a photosensitive layer with a thickness of 80 μm.
The film was then exposed to light at 500 mJ/cm ² through a negative mask using a Phoenix 3000 exposure machine manufactured by Oak Seisakusho Co., Ltd. In addition, the negative mask is placed 0.1 mm away from the photosensitive layer.
Exposure was carried out under atmospheric conditions. After exposure, the film was heated at 80°C for 5 minutes, left at room temperature for 30 minutes, and then developed by spraying with 1,1,1-trichloroethane at 20°C for 90 seconds. Next, using a Toshiba ultraviolet irradiation device manufactured by Toshiba Denzai Co., Ltd. (rated voltage 200V, rated power consumption 7.2KW, compatible lamp H5600L/2, number of lamps 1),
After irradiation at 1 J/cm ² , heat treatment was performed at 150° C. for 30 minutes to obtain a solder mask with excellent dimensional accuracy comparable to a negative mask. This solder mask has excellent cold and thermal shock resistance and uses rosin flux A-226 (Tamura Kaken Co., Ltd.).
MIL-STD-202E 107D Condition B (-65
No cracks or peeling of the coating were observed in 50 cycles of thermal shock tests (at room temperature for 30 minutes, at room temperature for 5 minutes, at 125°C for 30 minutes), indicating that the product has excellent long-term reliability.

Example 2 122 parts of the photopolymerizable prepolymer-containing mixture () obtained in Example 1(a) (100 parts of photopolymerizable prepolymer,
22 parts of tripropylene glycol diacrylate),
30 parts of phthalic anhydride/diethylene glycol/acrylic acid (1/2/2 molar ratio) condensate, 30 parts of ultrafine talc (manufactured by Simgon Nippon Talc Co., Ltd.), 1-(o-
EXAMPLE 1 A photosensitive resin composition of the present invention was prepared by kneading 4 parts of (tolyl) biguanide and 0.1 part of phthalocyanine green using three rolls.

Thereafter, a cured film with excellent heat resistance was obtained in the same manner as in Example 1(c).

Example 3 (a) Synthesis of photopolymerizable prepolymer A Orthocresol novolak type epoxy resin, ECN1235 (manufactured by Ciba Geigy, epoxy equivalent: 230) 460 parts Ethyl carbitol acrylate 460 parts B Acrylic acid 140 parts Benzyltriethylammonium chloride 0.1 part p-Methoxyphenol 0.6 part C Isocyanate ethyl methacrylate 77.5 parts Dibutyl tin dilaurate 0.1 part D Methanol 5 parts Orthocresol novolac type epoxy resin/acrylic acid was prepared in the same manner as in Example 1(a) using A to D. A mixture () containing 80% by weight of a photopolymerizable prepolymer based on /isocyanate ethyl methacrylate (acid equivalent/epoxy equivalent ratio = 0.25, isocyanate equivalent/hydroxyl group equivalent ratio = 1) was obtained.

(b) Preparation of photosensitive resin composition 125 parts of the photopolymerizable prepolymer/photopolymerizable monomer mixture () obtained in (a) (100 parts of photopolymerizable prepolymer)
parts, 25 parts of ethyl carbitol acrylate), trimethylhexamethylene diisocyanate/2-
Hydroxyethyl acrylate (1/2 molar ratio)
100 parts of reactants, 6 parts of antimony trioxide, 2,4-
4 parts of diethylthioxanthone, 4 parts of ethyl dimethylaminobenzoate, Phosma M (phosphate ester manufactured by Yushi Products Co., Ltd.) equimolar salt with benzotriazole
0.1 part and 3 parts Victoria Pure Blue 0.02 part
The photosensitive resin composition of the present invention was prepared by kneading using this roll.

Thereafter, a cured film with excellent heat resistance was obtained in the same manner as in Example 1(c).

Further, the photosensitive resin composition was coated with a thickness of 0.8 mm.
When applied to both sides of a UL94V-0 glass epoxy flame retardant base material (MCL-E-67 manufactured by Hitachi Chemical Co., Ltd.) to form a cured film with a thickness of 75 μm,
It was found that it maintains flame retardancy of UL94V-1.

Example 4 (a) Photopolymerizable prepolymer synthesis A Bisphenol A type epoxy resin, Epicote 828 (epoxy equivalent: 190) 380 parts B Methacrylic acid 86 parts Benzyltrimethylammonium chloride 0.3 parts p-methoxyphenol 0.6 parts C Isocyanate ethyl methacrylate 31 parts Dibutyltin dilaurate 0.1 part D Methanol 5 parts Bisphenol A type epoxy resin/methacrylic acid/
Isocyanate ethyl methacrylate (acid equivalent/
A mixture (2) containing a photopolymerizable prepolymer (epoxy equivalent ratio = 0.5, isocyanate equivalent/hydroxyl group equivalent ratio = 0.2) was obtained.

(b) Preparation of photosensitive resin composition Mixture containing the photopolymerizable prepolymer obtained in (a)
100 parts, trimethylhexamethylene diisocyanate/2-hydroxyethyl acrylate (1/
2 molar ratio) 200 parts of reactant, 15 parts of 2-hydroxyethyl methacrylate, 60 parts of Simgon (ultrafine talc manufactured by Nippon Talc Co., Ltd.), 4 parts of 2,4-diethylthioxanthone, 5 parts of isobutyl dimethylaminobenzoate, and Kyurazol. A photosensitive resin composition of the present invention was prepared by blending twice the amount of 2E4MZ-A (imidazole curing agent manufactured by Shikoku Fine Chemicals Co., Ltd.) and mixing with three rolls.

Thereafter, a cured film with excellent heat resistance was obtained in the same manner as in Example 1(c).

Example 5 (a) Synthesis of photopolymerizable prepolymer A Bisphenol A type epoxy resin, Epicoat 1001 (epoxy equivalent: 470, hydroxyl equivalent: 350)
235 parts tripropylene glycol diacrylate
150 parts B Acrylic acid 30 parts Benzyltrimethylammonium chloride 0.6 parts p-methoxyphenol 0.8 parts C Isocyanate ethyl methacrylate 168 parts Dibutyltin dilaurate 0.1 parts D Methanol 5 parts Using A to D, otherwise the same as Example 1(a) A mixture containing 73% of bisphenol A type epoxy resin/acrylic acid/isocyanatoethyl methacrylate (acid equivalent/epoxy equivalent ratio = 0.62, isocyanate equivalent/hydroxyl group equivalent ratio = 1) based photopolymerizable prepolymer () I got it.

(b) Preparation of photosensitive resin composition 137 parts of the photopolymerizable prepolymer/photopolymerizable monomer mixture () obtained in (a) (100 parts of photopolymerizable prepolymer)
37 parts ethyl carbitol acrylate), trimethylhexamethylene diisocyanate/2-
Hydroxyethyl acrylate (1/2 molar ratio)
100 parts of reactants, 60 parts of simgon, 4 parts of 2,4-diethylthioxanthone, 5 parts of isobutyl dimethylaminobenzoate, and Cyuazol C ₁₁ Z-AZINE
(manufactured by Shikoku Fine Chemicals Co., Ltd., imidazole-based curing agent) was kneaded using 3 rolls to prepare a photosensitive resin composition of the present invention.

Thereafter, a cured film with excellent heat resistance was obtained in the same manner as in Example 1(c).

Claims (1)

[Claims] 1 (a) An unsaturated compound obtained by addition-reacting a compound having at least one epoxy group and an unsaturated carboxylic acid at an acid equivalent/epoxy equivalent ratio in the range of 0.1 to 0.98. , isocyanate ethyl methacrylate is added to the hydroxyl group of the unsaturated compound, and the isocyanate equivalent/hydroxyl group equivalent ratio is
A photopolymerizable prepolymer obtained by reacting in the range of 0.1 to 1.2, containing (b) a photopolymerizable monomer and (c) a sensitizer and/or a sensitizer system that generates free radicals by actinic light. A photosensitive resin composition.