JPH04204452A - Production of photosensitive resin - Google Patents

Abstract

PURPOSE:To produce a photosensitive resin having high sensitivity, satisfactory shelf stability and slight unevenness by dissolving or suspending a specified alcohol compd. and carbodiimides in a solvent, dropping polyamic acid having specified repeating constituent units or adding the acid little by little and bringing them into a reaction. CONSTITUTION:An alcohol compd. having an acryl or methacryl group represented by formula I and carbodiimides are dissolved or suspended in an aprotic polar solvent at <=70 deg.C, polyamic acid having repeating constituent units represented by formula II is dropped or added little by little and they are brought into a reaction. In formula I, R1 is an org. group, R2 is H or CH3 and p is an integer of 1-5. In formula II, each of R3 and R4 is an org. group and n is 1 or 2. A photosensitive resin having high sensitivity, satisfactory shelf stability and no unevenness can easily be produced at a high rate of ester substitution.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a photosensitive resin that has extremely high sensitivity, good storage stability, and little variation.

[Conventional technology] Conventionally, surface protection films and interlayer insulating films of semiconductor elements, etc.
Polyimide is used because it has excellent heat resistance, as well as excellent electrical insulation and mechanical strength, but recently technology has been developed to impart photosensitivity to polyimide itself in order to simplify the complicated process of creating polyimide patterns. It is attracting attention.

For example, a polyimide precursor composition to which a photosensitive group is added with an ester group having a structure as shown in the following formula (for example, Japanese Patent Publication No. 55-414
22 Publication), etc. are known.

All of these are dissolved in a suitable organic solvent, applied as a varnish, dried, exposed to ultraviolet light through a photomask, developed and rinsed to obtain the desired pattern, and then heat-treated to form a polyimide. It is a coating.

Using photosensitive polyimide not only simplifies the pattern creation process, but also eliminates the need to use highly toxic etching solutions, making it safer and less polluting. It is expected that this technology will become even more important in the future.

However, the method for introducing an ester group is to first react an acid dianhydride with an alcohol-containing photosensitive group, and then copolymerize it with a diamine using a chlorine-containing compound such as acid chloride as a condensing agent (Japanese Patent Publication No. 55-41422 Publication No.),
In addition, as a method that does not use chlorine-containing compounds, a method that uses carbodiimides as a condensing agent instead (Japanese Patent Application Laid-open No. 60-2
28537), etc. are known. However, in both methods, carboxylic acids and diamines must be polycondensed under mild conditions such that carbon-carbon double bonds do not react, making it difficult to obtain high-molecular-weight products, and furthermore, the molecular weight and photosensitivity vary between synthesis lots. There was a large variation in the group substitution introduction rate. For this reason, photosensitive resin compositions obtained from this resin have low sensitivity and cured films with low mechanical properties. Furthermore, as a method to solve these problems, a method of first synthesizing a high molecular weight polyamic acid and introducing an ester bond via isoimide (Japanese Patent Application Laid-open No. 61-2
54547) is also known. However, with this technology, isoimide is an unstable compound, and imidization progresses depending on the conditions, resulting in a decrease in the substitution rate of esters containing photosensitive groups and gelation of the resin, resulting in only resins with extremely large manufacturing variations. I couldn't get it.

As described above, a technique of introducing a photosensitive group into the carboxyl group of polyamic acid in the form of an ester has been known, but such a technique produces a resin with a high ester substitution rate, a low imidization rate, and a large molecular weight. That was difficult. For this reason, photosensitive resin compositions obtained from these resins have drawbacks such as low sensitivity or poor storage stability.

[Problems to be Solved by the Invention] The purpose of the present invention is to use a polyamic acid ester type photosensitive resin in which an acrylic (methacrylic) group is introduced into the carboxyl group in a polyamic acid at a high molecular weight, and imidization progresses. The object of the present invention is to provide a method for easily eliminating variations in the ester substitution rate at a high ester substitution rate.

[Means for Solving the Problems] The present invention provides an alcohol compound having an acrylic or methacrylic group represented by the following formula CI) and (wherein R: organic group, R2: H or CH3, p: 1- 5 (an integer of
:organic group, n:l or 2) is added dropwise or little by little to react.

The alcohol compound having an acrylic or methacrylic group represented by the formula [I] used in the present invention reacts with the carboxyl group of the polyamic acid with the alcohol group, grafts it to the polyamic acid side chain with an ester bond, and further When the methacrylic group undergoes a photocrosslinking reaction, it becomes a raw material for negative photosensitive resin. In the alcohol compound having an acrylic or methacrylic group, the number of acrylic or methacrylic groups (p in formula [I]) is 1 to 5.
is preferred. 0 is not preferable because it does not contain acrylic or methacrylic and the photocrosslinking reaction does not proceed. or,
If it is 6 or more, it is not only difficult to produce it industrially, but also the molecular weight becomes large and the compatibility with polyamic acid decreases, which is not preferable. Examples of alcohol compounds having an acrylic or methacrylic group include pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol acrylate dimethacrylate, pentaerythritol diacrylate methacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, and glycerol diacrylate. , glycerol dimethacrylate, glycerol acrylate methacrylate,
Trimethylolpropane diacrylate, 1,3-diacryloylethyl-5-hydroxyethyl isocyanurate, 1,3-dimethacrylate-5-hydroxyethyl isocyanurate, ethylene glycol-modified pentaerythritol triacrylate, propylene glycol-modified pentaerythritol triacrylate , trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, glycidyl methacrylate, glycidyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, polyethylene glycol modified methacrylate, polyethylene glycol modified Examples include, but are not limited to, acrylate, polypropylene glycol-modified acrylate, and polypropylene glycol-modified methacrylate. When using these, one type or a mixture of two or more types may be used.

In the present invention, carbodiimides are used as a dehydrating agent during the esterification reaction between the carboxyl group of polyamic acid and the alcohol group of an alcohol compound having an acrylic or methacrylic group. As methods for accelerating the esterification reaction, there are known methods such as via acid chloride, using acid or alkali as a catalyst, and using trifluoroacetic anhydride as a dehydrating agent. The method described above is also undesirable because it cannot avoid a large amount of ionic impurities being mixed into the reaction system.

Examples of carbodiimides include N,N-dicyclohexylcarbodiimide, N,N-diisopropylcarbodiimide, and the like, but are not particularly limited.

In the present invention, the aprotic polar solvent is used to dissolve or suspend an alcohol compound having an acrylic or methacrylic group, carbodiimides, and further polyamic acid. Examples of the aprotic polar solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N,
N-diethylacetamide, N,N-dimethylmethoxyacetamide, dimethylsulfoxide, hexamethylphosphamide, N-methyl-2-pyrrolidone, pyridine, dimethylsulfone, tetramethylenesulfone, dimethyltetramethylenesulfone, methylformamide, N-
Acetyl-2-pyrrolidone, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether are used alone or in combination. In addition, non-solvents such as benzene, benzonitrile, dioxane, butyrolactone, xylene, toluene, and cyclohexane can also be used in combination as solvents.

The polyamic acid having a repeating structural unit represented by the formula [I] used in the present invention is a compound that forms a rimide ring by heat treatment and a highly heat-resistant film can be obtained. This polyamic acid is usually obtained by reacting a diamine and an acid anhydride in an aprotic polar solvent.

In formula (II), R3 is a divalent organic group, and aromatic diamine and/' or a derivative thereof is usually used for introduction thereof. For example, l-phenylene-diamine, 1-itubrobyl-2,4-phenylene-diamine, ρ-phenylene-cyamine, 4,4'-diamino-diphenylpropane, 3,3"-diamino-diphenylpropane, 4゜4
'-Diamino-diphenylethane, 3,3'-diamino-diphenylethane, 4,4'-diamino-diphenylmethane, 3,3'-diamino-diphenylmethane, 4.
4'-diamino-diphenyl sulfide, 3,3'-diamino-diphenyl sulfide, 4,4'-diamino-
diphenyl sulfone, 3,3'-diamino-diphenyl sulfone, 4,4'-diamino-diphenyl ether,
3,3'-diamino-diphenyl ether, benzidine, 3,3'-diamino-biphenyl, 3,3'-dimethyl-4,4'-diamino-biphenyl, 3,3'-dimethoxy-benzidine, 4°4''- Diamino-p-terphenyl, 3.3”-diamino-p-terphenyl, bis(p-amino-cyclohexyl)methane, bis(p-β
-amino-t-butylphenyl)ether, bis(p-
β-methyl-δ-aminopentyl)benzene, p-bis(2-methyl-4-amino-pentyl)benzene, p-
Bis(1,1-dimethyl-5-amino-pentyl)benzene, 1,5-diamino-naphthalene, 2,6-dichloronaphthalene, 2,4-bis(β-amino-1-butyl)toluene, 2,4 -diamino-1-luene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylene-diamine, p-xylylene-diamine, 2,6-cyamitubiridine, 2,5 -diaminobinodine, 2,5-diamino-1,3,4-oxadiazole, 1,4-diamino-cyclohexane, piperazine, methylene-diamine, ethylene-diamine,
Propylene-diamine, 2,2-dimethyl-propylene-diamine, tetramethylene-diamine, pentamethylene-diamine, hexamethylene-diamine, 2,5-dimethyl-hexamethylene-diamine, 3-methoxy-hexamethylene-diamine, hepta methylene-diamine,
2,5-dimethyl-hebutamethylene-diamine, 3-methyl-hebutamethylene-diamine, 4,4-dimethyl-
Hebutamethylene-diamine, octamethylene-diamine, nonamethylene-diamine, 5-methyl-nonamethylene-diamine, 2,5-dimethyl-nonamethylene-diamine, decamethylene-diamine, 1,10-diamino-1
, 10-dimethyl-decane, 2,11-diamino-dodecane, 1,12-diamino-octadecane, 2,12-
Diamino-octadecane, 2,17-diaminosiloxane, diaminosiloxane, 2,6-diamino-4-carboxylic benzene, 3,3'-diamino-4,4'
- Examples include dicarboxylic benzidine,
It is not limited to these. In addition, in use, it may be of any type or a mixture of two or more types.

In the formula [: II), R4 is introduced from a compound having a trivalent or tetravalent organic group, and usually aromatic tetracarboxylic acids or derivatives thereof and aromatic tricarboxylic acids or derivatives thereof are mainly used. For example, trimellitic anhydride, pyromellitic dianhydride, benzene-1,2,3
, 4-tetracarboxylic dianhydride, 3°3', 4.4'
-benzophenonetetracarboxylic dianhydride, 2.2'
, 3.3'-benzophenonetetracarboxylic dianhydride, 2,3.3',4'-hensiphenonetetracarboxylic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride , naphthalene-1,2,5,6-tetracarboxylic dianhydride, naphthalene-1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8
-Tetracarboxylic dianhydride, naphthalene-1,2,6
,7-tetracarboxylic dianhydride, 4,8-di,methyl-1,2,3゜5.6.7-hexahydronaphthalene-
1,2,5,6-tetracarboxylic dianhydride, 4.8-
dimethyl-1,2,3,5,6,7-hexahydronaphthalene-2.3,6.7-tetracarboxylic dianhydride,
2.6-cyclonaphthalene-1.4,5,8-tetracarboxylic dianhydride, 2.7-cyclonaphthalene-1
．． 4,5.8-tetracarboxylic dianhydride, 2,3.
6゜7-te1~lachloronaphthalene-1,4,5.8-
Tetracarboxylic dianhydride, 1,4,5.8-tetrachloronaphthalene-2,3,6,7-tetracarboxylic dianhydride, 3.3',4゜4'-diphenyltetracarboxylic dianhydride Thing, 2.2'.

3.3'-diphenyltetracarboxylic dianhydride, 2,
3゜3', 4'-diphenyltetracarboxylic dianhydride, 3゜3", 4.4"-p-terphenyltetracarboxylic dianhydride, 2.2", 3.3"-p-ter Phenyltetracarboxylic dianhydride, 2,3.3″, 4″
-p-terphenyltetracarboxylic dianhydride, 2,2
-bis(2,3-dicarboxyphenyl)-propanihydride, 2,2-bis(3,4-dicarboxyphenyl)-propanianhydride, bis(2,3-dicarboxyphenyl)ether dianhydride, bis (3,4-dicarboxyphenyl)ether dianhydride, bis(2,3-dicarboxyphenyl)methanidianhydride, bis(3,4-dicarboxyphenyl)methanidianhydride, bis(2,3-dicarboxyphenyl) ) sulfonic anhydride, bis(3,4
-dicarboxyphenyl)sulfone dianhydride, 1,1-
Bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, perylene-2,3,8°9-tetracarboxylic dianhydride, perylene -3,4,9,10-tetracarboxylic dianhydride, perylene-4,5,10゜11-tetracarboxylic dianhydride, perylene-5,6,11゜1
2-tetracarboxylic dianhydride, phenanthrene-1,
2,7,8-tetracarboxylic dianhydride, phenanthrene-1,2,6,7-tetracarboxylic dianhydride, phenanthrene-1,2,9,10-tetracarboxylic dianhydride, cyclopentane- 1,2,3,4-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, thiophene Examples include, but are not limited to, -2,3,4,5-tetracarboxylic dianhydride. In addition, when using
It may be of any type or a mixture of two or more types.

The degree of polymerization of the polyamic acid in the present invention is not particularly limited, but those having a degree of polymerization of 5 to 10,000 are usually used, more preferably about 20 to 1,000.

If the degree of polymerization is 5 or less, the heat resistance, mechanical strength, elongation rate, etc. when converted into polyimide after curing are undesirable. If it is more than 10,000, the viscosity not only increases and becomes difficult to handle, but also requires lowering the resin concentration of the solution in order to maintain a constant viscosity, which lowers the solution concentration during pattern formation, resulting in a flat surface. This is not preferable because the coverage is significantly reduced, and in the case of a stepped substrate such as a semiconductor, the thickness at a portion of the stepped corner becomes thinner, and the coating film is more likely to crack at the stepped portion.

The terminal of the polyamic acid in the present invention is not particularly limited, but it may be an acid anhydride-terminated type, use of a terminal terminator such as phthalic anhydride, or a structure in which an acid anhydride is terminated with an alcohol compound having an acrylic or methacrylic group. Preferably. The presence of an amino group at the terminal is not preferred because this amine group reacts with the carboxyl group of the polyamic acid activated with carbodiimides and tends to gel. More preferred is a polyamic acid having a structure in which the terminal acid anhydride is terminated with an alcohol compound having an acrylic or methacrylic group, that is, a polyamic acid represented by the following formula (III) having an actinic radiation-sensitive group P' at the terminal.

(In the formula, R3, R4 = organic group, R1: organic group, R2: H or CH3, p: an integer of 1 to 5, m: 5 to 10000) An example of the method for synthesizing the polyamic acid used in the present invention is shown below. When we want to synthesize a polyamic acid with a degree of polymerization m of about 1000, we need 1001 mol of an acid anhydride and a compound 2 having an actinic radiation-reactive group P''.
moles can be obtained by first reacting in an inert aprotic polar solvent and then reacting a further 1000 moles of the diamine.

In the method for producing a photosensitive resin in the present invention, an alcohol compound having an acrylic or methacrylic group and a carbodiimide are dissolved or suspended in an aprotic polar solvent at 70°C or less, and the polyamic acid is added thereto. It is necessary to carry out the reaction by dropping or adding in small quantities. On the other hand, in the method of first adding a hecarbodiimide in polyamic acid to form isoimide (for example, JP-A-61-254547, JP-A-278531), isoimide is unstable and is easily imidized. This is not preferable because it not only reduces the production rate of ester substituted products but also reduces storage stability.

In the method of the present invention, polyamic acid is directly esterified without going through isoimide, so the production rate of ester substituted products is improved, and as a result, higher sensitivity and improved storage stability can be achieved. Ta.

Moreover, this ester reaction is preferably carried out at 70°C or lower, more preferably in the range of 0 to 50°C. If the temperature is 70°C or higher, the acrylic or methacrylic compound tends to undergo thermal polymerization, and the storage stability of the resulting ester-substituted polyamic acid decreases, which is not preferable.

The photosensitive resin obtained by the present invention is usually added dropwise to a poor solvent such as water, methanol or ethyl alcohol for the purpose of purifying the product, precipitating the product, filtering it out, and drying it again using an aprotic polar solvent. Use by dissolving it in etc. As the solvent used for dissolution, in addition to aprotic polar solvents, amide compounds containing carbon-carbon double bonds, etc. can also be used. Examples of the amide compound containing this carbon-carbon double bond include N-methylacrylamide, N-ethylacrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N,N-dimethylacrylamide,
N, N-diethylacrylamide, N-acryloylpiperidine, N-acryloylmorpholine, N.

Examples include, but are not limited to, N-dimethylmethacrylamide, N,N-diethylmethacrylamide, N,N-dimethylaminoethylmethacrylamide, and the like.

Further, when the photosensitive resin obtained according to the present invention is used, it is desirable to add a photosensitizer for the purpose of improving the sensitivity. The sensitizer used in the present invention is particularly 330 to 500n
A compound having an absorption maximum wavelength (λmax) at m is preferred. If λlaX is 330 nm or less, light is absorbed by the polyamic acid itself and no photoreaction is possible, which is not preferable. Moreover, if it is 5000 m or more, it is not preferable because it will undergo a photoreaction with visible light, making it necessary to set up a work place in a shielded room, and the ease of handling will deteriorate.

Examples of the sensitizer of the present invention include, but are not limited to, "Cl0-Cl0-".Furthermore, in use, one type or a mixture of two or more types may be used.

An adhesion aid, a leveling agent, and various other fillers may be added to the photosensitive resin composition of the present invention.

The method of using the photosensitive resin composition according to the present invention is to first apply the composition to a suitable support such as a silicon wafer, ceramic, or aluminum substrate. Application methods include rotational coating using a spinner, spray coating using a spray coater, dipping, printing, and roll coating. Next, after drying the coating film by prebaking at a low temperature of 60 to 80°C, the desired pattern shape is irradiated with actinic radiation. As the actinic radiation, X-rays, electron beams, ultraviolet rays, visible light, etc. can be used, but those having a wavelength of 200 to 500 nII are preferable.

Next, a relief pattern is obtained by dissolving and removing the unirradiated areas with a developer. As a developer, N-methyl-2
-pyrrolidone, N,N-dimethylacetamide, N,N
- Dimethylformamide, methanol, isopropyl alcohol, water, etc. are used alone or in combination. As the developing method, methods such as spray, paddle, immersion, and ultrasonic waves can be used.

Next, the relief pattern formed by development is rinsed. As the rinsing liquid, methanol, ethanol, isopropyl alcohol, butyl acetate, etc. are used. Next, heat treatment is performed to form imide rings and obtain a final pattern with high heat resistance.

The photosensitive resin composition according to the present invention is useful not only for semiconductor applications but also as an interlayer insulating film for multilayer circuits, a cover coat for flexible copper clad boards, a solder resist film, a liquid crystal alignment film, and the like.

The present invention will be specifically explained below using Examples.

(Example 1) 322 g (1, Omol) of 3.3',4.4'-benzophenonetetracarboxylic dianhydride and 11.4 g of glycerol dimethacrylate (0,050101
) was added to 2890 g of N-methyl-2-pyrrolidone and reacted at 50°C for 16 hours. Then 4,4'
-diaminodiphenyl ether 200g (1, Omo
1) was added and reacted at 20°C for 6 hours.

612 g of the obtained polyamic acid solution (solid content: 10
0g) was transferred to the dropping funnel. 370 g (0,18a+ol) of dicyclohexycarbodiimide and 220 g (1,0 mol) of glycerol dimethacrylate were dissolved in N-methyl-2-pyrrolidone. The polyamic acid solution was added dropwise to the flask at 30° C. over 2 hours with stirring. After the completion of dripping, another 50
The reaction was carried out at °C for 5 hours to obtain a slurry-like reaction product.

After separating dicyclohexyurea by filtration, it was reprecipitated in ethanol,
The solids were filtered and dried under reduced pressure.

The obtained polymer has an ester substitution rate (the higher the better)
11 (-As a result of measuring the NMR spectrum, 9
It was high at 7%, and the imidization rate (the lower the better) was low at below the measurement detection limit. Further, the molecular weight was measured by GPC method and was as high as M = 25,000.

Furthermore, 100 g of this obtained polymer was added to N-methyl-
Dissolved in 200 g of 2-pyrrolidone, and further added 1 g of methyl ether hydroquinone as an inhibitor and 5 g of Michler's ketone (λmaχ365 nm) as a photosensitizer.
was added and dissolved at room temperature. The resulting composition was applied onto a silicon wafer using a spinner and dried for 50 minutes in a dryer.
The film was dried at C for 1 hour to obtain a film with an approximately LOA of 1 m.

This film is coated with a Kodak Photographic Step Tablet No. 2.21 Step (in this gray scale, as the number of steps increases, the amount of transmitted light increases by 17 steps from the previous step).
(The larger the remaining stage after development, the better the sensitivity), and then irradiated with ultraviolet rays of 10100 O/c+n2, and then using a developer consisting of 60 g of N-methyl-2-pyrrolidone and 40 g of xylene. After development and rinsing with isopropyl alcohol, the pattern remained up to 16 steps, indicating high sensitivity.

Furthermore, the obtained resin composition showed no change in viscosity and no decrease in sensitivity even after being left at room temperature for one month, indicating that it had excellent storage stability.

(Comparative Example 1) 322 g (1.0 mol) of 3.3',4.4'-benzophenonetetracarboxylic dianhydride and 231 g (231 g) of 2-hydroxy-1,3-dimethacryloxypropane (
After esterifying a part of the carboxyl group with 1,05 fflol), 4,4'-diaminodiphenyl ether 1
A polyamic acid ester copolymer was obtained by using 70.2 g (0.85 mol) of dicyclohexylcarbodiimide as a condensing agent. After removing dicyclohexyurea by filtration, it was reprecipitated in ethanol, and the solid matter was filtered and dried under reduced pressure.

The obtained polymer had an ester substitution rate of % and an imidization rate of 8%. However, the molecular weight was as low as Higashi=5000. Therefore, the reaction was carried out again in the same manner, but the ester substitution rate was 85%, the imidization rate was 16%, and M = 8000. Not only was a high molecular weight product not obtained, but the variation was large.

Next, according to Example 1, photosensitive resin compositions were obtained and similarly evaluated, and the step tablets had low sensitivity of 9 steps and 8 steps.

(Comparative Example 2) 612 g of polyamic acid obtained in Example 1 (to
og) in a flask, and 37 g (0.18 mol) of dicyclohexycarbodiimide was added dropwise thereto at 20°C.
The mixture was reacted for 2 hours to produce BoI/isoimide.

In addition, 220g of glycerol dimethacrylate
was added and reacted at 50°C for 5 hours. The obtained slurry-like reaction product was treated in the same manner as in Example 1 to obtain a polymer.

The ester substitution rate of the obtained polymer was as low as 65%, and the imidization rate was as high as 32%. Also, the molecular weight is Mn=21
It was 000.

Furthermore, when a resin composition was obtained in the same manner as in Example 1 and evaluated in the same manner, the number of step tablets was as low as 10, and in the storage test, it gelled on the third day, making it less practical. It turned out that.

[Effects of the Invention] According to the present invention, a high molecular weight polyamic acid is first synthesized, and this is mixed with a carbodiimide having an acrylic or methacrylic group in an aprotic polar solvent such as N-methyl-2-pyrrolidone. The photosensitive resin obtained by the method of directly synthesizing ester-substituted polyamic acid by dropping or adding it little by little into a solution in which an alcohol compound is dissolved or suspended at 70 ° C or less has a high ester substitution rate, It was found that a product with a low imidization rate and a large molecular weight could be easily obtained with good reproducibility.

Furthermore, the photosensitive resin composition obtained from this photosensitive resin had high sensitivity and excellent storage stability. In the present invention, there was no problem even if additives other than the essential components were added to impart various properties.

Claims (1)

[Claims] (1) An alcohol compound having an acrylic or methacrylic group represented by the following formula [I], and ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [I] (In the formula, R_1: organic group, R_2: H or CH_3, p
: An integer from 1 to 5) Carbodiimides are dissolved or suspended in an aprotic polar solvent at 70°C or below to produce polyamic acid having a repeating structural unit represented by the following formula [II] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼... [II] (In the formula, R_3, R_4: organic group, n: 1 or 2) A method for producing a photosensitive resin, which is characterized by dropping or adding and reacting little by little.