JPH02158736A - Photosensitive resin composition - Google Patents

Abstract

PURPOSE:To obtain a photosensitive resin compsn. being developable with a safe and inexpensive aq. alkali, and to obtain a solder mask having improved revolving power and heat resistance in humid state by constituting the compsn. of a specified photosensitive resin compsn. CONSTITUTION:An oligomer having carboxyl groups and photoreactive unsatd. groups in side chains and being soluble in an aq. soln. of alkali, triglycidyl isocyanurate, amino resin, a sensitizer and/or a mixture thereof which generates free radicals by the irradiation with active rays, and a heterocyclic compd. having one thiol group, are contained in the photosensitive resin compsn. Thus, the compsn. becomes developable with an aq. soln. of alkali having high safety and low price, and provides a solder mask having high reliability having high preservation stability, high resolving power, and high resistance to soldering.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a photosensitive resin composition, and more specifically, a photosensitive resin composition for forming a protective film that can be used in printed wiring board manufacturing, metal precision processing, etc. Regarding.

(Conventional technology) Traditionally, solder masks are used in printed wiring board manufacturing.

Photosensitive resin compositions having excellent properties that can be used as resists for chemical plating and the like are known. The main purpose of a solder mask is to limit the soldering area during soldering and prevent solder bridging.

The purpose is to prevent corrosion of bare copper conductors and maintain electrical insulation between conductors over a long period of time.

Usually, as a solder mask, a printed mask whose main component is a thermosetting resin such as epoxy resin or aminoblast resin is used.

However, in recent years, the wiring density of printed wiring boards has increased.

In addition, the requirements for electrical insulation between conductors have become stricter, and the solder masks used therein are also required to be thick and have excellent dimensional accuracy, which can no longer be met by screen printing methods.

Therefore, a thick film (normally 25 μm on the conductor is desired) is applied using the Atsushi method (a method of forming an image by image-wise exposure followed by development).
There is a desire for a photosensitive resin composition that can form a highly reliable solder mask with excellent dimensional accuracy.

Conventionally, as a photosensitive resin composition for forming a solder mask,
Photosensitive resin composition containing an acrylic polymer and a photopolymerizable monomer as main components <*Kokai 53-56018,
JP-A-54-1018, etc.) are known.

However, since these photosensitive resin compositions use a large amount of acrylic polymer to impart film properties, they have the disadvantage that the cured film does not have sufficient heat resistance.

On the other hand, as a heat-resistant photosensitive resin composition, a composition containing a photosensitive epoxy resin having a chalcone group in the main chain and an epoxy resin curing agent as the main components (Japanese Patent Laid-Open No. 54-82073
JP-A No. 58-62636, etc.) have been proposed. but.

Since these photodimerizable photosensitive resin compositions have low sensitivity, it is difficult to form a thick resist film.

Rounding requires the use of a flammable organic solvent such as cyclohexanone as a developer, which is dangerous from a safety standpoint.

As a photosensitive resin composition for forming a thick-film cured and re-extended solder mask, a composition (%
Publication No. 61-272, etc.) have been proposed. Although these compositions have excellent heat resistance and are useful, they require the use of a 1.1.1-trichloroethane/lower alcohol mixture as a developer, which poses a problem in developer management.

Also.

1.1.1- The use of IJ chloroethane is undesirable from the standpoint of environmental conservation as there is a risk of groundwater contamination.

A photosensitive resin composition for forming a solder mask that can be developed with an alkaline aqueous solution and has excellent safety and economical efficiency includes a composition whose main components are a carboxyl group-containing polymer, a monomer, a photopolymerization initiator, and a thermosetting resin ( %Kaisei 48-73148
Publication No. 178237/1983, Japanese Patent Application Laid-open No. 178237/1983
-42040, 9%, 1983-151152, etc.) are known. In these compositions, epoxy resins, melamine resins, urea resins, etc. are used as thermosetting resins, and examples have also been disclosed in which epoxy resins insoluble in organic solvents, such as triglycidyl isocyanurate, are used in a dispersed manner. However, these compositions cannot necessarily be said to have sufficient properties such as foldability, solvent resistance, and resistance to soldering heat when absorbing moisture.

JP-A No. 61-243869 discloses an oligomer obtained by reacting a reaction product of a novolac type epoxy resin with acrylic acid (acid equivalent/epoxy equivalent ratio 0.95 to 1.05) and an acid anhydride. A liquid resist ink composition for forming a solder mask containing a polymerization initiator, an epoxy resin such as triglycidyl isocyanurate, and a diluent has been proposed.

This composition is developable with an alkaline aqueous solution.

Although it has excellent properties as a solder mask and is useful, it cannot be developed within one day at 40° C. after adding the epoxy resin, and the problem of storage stability remains.

(Problem to be solved by the invention) The object of the present invention is to eliminate the drawbacks of the prior art.

Provided is a photosensitive resin composition that can be used to form a highly safe and economical alkaline aqueous solution, and is also excellent in storage stability, resolution, and soldering heat resistance during moisture absorption, and is capable of forming a highly reliable solder mask. Then there is K.

(Means of rounding to solve problems) The present invention is.

(a) An oligomer having a carboxyl group and a photoreactive unsaturated group in its side chain and being soluble in an alkaline aqueous solution (b) Triglycidyl isocyanurate.

(C1 amino resin.

[dl] A sensitizer and/or sensitizer system that generates free radicals upon irradiation with actinic rays, and (e) a photosensitive resin composition containing a peterocyclic compound having one thiol group.

The photosensitive resin composition of the present invention has a carboxyl group and a photoreactive unsaturated group in the side chain as an essential component (al),
Contains oligomers that are soluble in aqueous alkaline solutions.

Such oligomers are already known, for example, in Japanese Patent Publication No. 51-28677.

Japanese Patent Publication No. 59-19130, Japanese Patent Publication No. 61-2438
It is described in Publication No. 69, etc.

Preferred oligomers include at least one novolak epoxy resin selected from the group consisting of orthocresol novolac epoxy resins, phenol novolak epoxy resins, and halogenated phenol novolak epoxy resins, and an unsaturated carboxylic acid. t
/Additional reaction ♂ with an epoxy equivalent ratio in the range of 0.5 to 1.05
Examples include oligomers obtained by reacting the secondary hydroxyl groups and residual epoxy groups of the resulting unsaturated compound with a saturated or unsaturated polybasic rR anhydride.

The novolac type epoxy resin used in the present invention is obtained by reacting, for example, orthocresol, phenol, halogenated phenol, etc. with an aldehyde in the presence of an acid catalyst. It is obtained by reacting epichlorohydrin and is commercially available.

As an orthocresol novolac type epoxy resin, 1
For example, manufactured by Ciba Geigy, Araldai) ECN129
9 (softening point 99°C, epoxy equivalent 230), ECN12
80 (softening point 80°C, epoxy equivalent 230), ECN
1273 (softening point 73°C, epoxy f#230),
Made by Nippon Kayaku ■, EOCN104 (softening point 90-1
00℃, Epoxy Naoki 225-245), ECN123
(Softening point 80-90℃, epoxy equivalent 215-235
L ECN~235), EoCNtol (softening point 6
5 to 69°C, 1L of epoxy 205 to 225), and the like.

As a phenol novolac type epoxy resin.

Example: Epicoat 152 (epoxy fi
i175), Epicor) 154 (epoxy equivalent weight 176
~181), manufactured by Dow Chemical Company, DEN431 (epoxy equivalent: 172-179), DEN438 (epoxy equivalent: 175-182), manufactured by Toto Kasei ■, YDPN-63
8 (epoxy equivalent 170-190), YDPN-601
(Epoxy equivalent: 180-220), YDPN-602 (
Epoxy equivalent: 180 to 220).

Examples of halogenated phenol novolak type epoxy resins include 9, manufactured by Nippon Kayaku ■, and BREN (epoxy equivalent: 27
0-300. Bromine content 35-37%, softening point 80-9
Examples include brominated phenol novolac type epoxy resins such as 0°C).

Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, β-furylacrylic acid, β-styrylacrylic acid, α
-Cyanocinnamic acid, cinnamic acid, acrylic acid oligomer represented by general formula (1) CH,=CHC00 (CH鵞C
H*C00) nH (" is an integer from 1 to 6) General formula (Ill
A reaction product of acrylic acid and caprolactone shown by C
Hs = CHCOO(Cm Hto COO)nH(
n is an integer of 1 to 3) (■) etc. are used. Compounds represented by formula (11) and formula (II) are publicly known and commercially available, such as Aronix M5600 (formula (
Compound represented by 11, where n is 1.2 to 1.4 on average
), Aronix M5300 (a compound represented by the formula (Ill, where n is 2 on average), etc. are used.

These unsaturated carboxylic acids can be used alone or in combination.

In the present invention, the addition reaction between these novolak-type epoxy resins and unsaturated carboxylic acids is carried out by a conventional method, but the acid equivalent/epoxy weight ratio is adjusted to 0.5 to 1.05.
! It is preferable that the When the acid pain Jft/epoxy equivalent ratio is less than 0.5, the photocured film tends to swell during the development process after image exposure.

When the acid equivalent/epoxy equivalent ratio exceeds 1.05,
Because the amount of free unsaturated carboxylic acid increases.

It tends to cause unfavorable safety issues such as skin irritation.

The addition reaction product of a novolac type epoxy resin and an unsaturated carboxylic acid can be prepared by dissolving the above novolac type epoxy resin in an inert organic solvent such as methyl ethyl ketone, methyl cellosolve acetate, ethyl cellosolve acetate, or cyclohexanone, and adding triethylamine or Trilo as a catalyst. Tertiary amines such as butylamine and diethylcyclohexylamine, quaternary ammonium salts such as benzyltrimethylammonium chloride and benzyltriethylammonium chloride, and polymerization inhibitors such as hydroquinone, p
-Methoxyphenol or the like is stirred and reacted with the unsaturated carboxylic acid at 70 to 110°C in the equivalent ratio range described above.

Examples of the saturated or unsaturated polybasic acid anhydrides used in the present invention include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methyl disubstituted butenyl tetrahydrophthalic anhydride. , itaconic anhydride, succinic anhydride, citraconic anhydride.

Alkenylic anhydride, dodecenylsuccinic anhydride, tricarballylic anhydride, maleic anhydride, lyluic acid adduct of maleic anhydride, a-rendic anhydride, maleic anhydride adduct of methylcyclopentadiene, alkylated endoalkylene tetrahydrophthalic anhydride Examples include acids.

In the present invention, the addition reaction between these polybasic acid anhydrides and the unsaturated compound is carried out at an acid equivalent/hydroxyl group equivalent ratio of 0.6 to 2. It is preferable to carry out using a conventional method as a range of 0. Since the unsaturated compound has an epoxy group, an addition reaction between the carboxyl group generated by the addition reaction of the polybasic acid anhydride to the secondary hydroxyl group and the epoxy group occurs, and the carboxyl group concentration of the resulting oligomer increases. descend. For this reason, determine the amount of polybasic acid anhydride used in advance.

It is desirable to increase the amount to compensate for the decrease.

Particularly preferred oligomers include phenol novolac type epoxy resin/acrylic acid/tetrahydrophthalic anhydride (acid equivalent/epoxy group equivalent ratio=0.5 to 1.05.
Acid equivalent/hydroxyl group equivalent ratio = 0.6 to 2) system oligomer, cresol novolac type epoxy resin/acrylic acid/tetrahydrophthalic anhydride (acid equivalent/epoxy group equivalent ratio = 0
．． 5-1.05° acid equivalent/hydroxyl group equivalent ratio = 0.6-2)
Examples include oligomers.

The photosensitive resin composition of the present invention contains triglycidyl isocyanurate as an essential component (b). Triglycidyl isocyanurate is a known compound,
Commercially available products such as TEP I C-8 and TEPIC-G manufactured and sold by Nichikagaku Kogyo ■,
TEPIC-P etc. can be used.

The photosensitive resin composition of the present invention contains an amine resin as an essential component (
Contained as C). In the present invention, the amine resin is
Initial condensate obtained by reacting an aldehyde with an amino group-containing compound such as melamine, urea, benzoguanamine, etc.2 For example, trimethylolmelamine, lamin, tetramethylolmelamine, hexamethylolmelamine, hexamethoxymethylmelamine, hexabutoxymethylmelamine , N
, N'-dimethylol urea, melamine resin manufactured by Mitsui Toatsu Cymel Co., Ltd. (Cynol 300, Cymel 3o1, Cymel 303, ? Cymel 325, Cymel 350, etc.).

Melamine resin manufactured by Hitachi Chemical ■ (Melan 523° Furan 623, Melan 2000, etc.) 9 Hitachi Chemical ■ Fissure urea resin (Melan 18???), Hitachi Chemical ■ Envy penzoguan e resin (Melan 362, etc.) etc. Can be mentioned. Particularly preferred amine resins include hexamethoxymethyl melamine and amine resins.

The photosensitive resin composition of the present invention contains as an essential component d) a sensitizer and/or a sensitizer system that generates υ free radicals upon irradiation with actinic rays.

Examples of the sensitizer include substituted or unsubstituted polynuclear quinones 2, such as 2-ethylanthraquinone, 2-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, λ3-diphenylanthraquinone, diacetyl pencil, etc. Ketoaldonyl compounds, benzoin, α-ketaldonyl alcohols and ethers such as biparone, α-hydrohydrocarbon-substituted aromatic acyloins such as α-phenyl-benzoin, α, α-jethoxyacetophenone, etc., benzophenone, 4.4 Aromatic ketones such as '-bisdialkylaminobenzophenone, 2
-Methylthioxanthone, 2+4-diethylthioxanthone, 2-chlorothioxanthone.

Thioxanthone such as 2-isopropylthioxanthone and 2-ethylthioxanthone, 2-methyl-1-(4-
(Methylthio)phenyl-2-morpholino-propane-1 is used, and these may be used alone or in combination.

As a sensitizer system, 0 e.g. 2.4.5- ) IJ allylimidazole dimer and 2-mercaptobenzoxane +
A/, o Ico Crystal Violet, Tris (4
A combination with -shi:r-f-ruamino-2-methylphenyl)methane or the like is used. In addition, additives such as triethanolamine for benzophenone, etc., which are dangerous in their photoinitiation properties by themselves, but can be used in combination with the above substances to create a sensitizer system with better photoinitiation performance as a whole. Tertiary amines, isoamyl dimethylaminobenzoate for thioxanthone, N-methyldietalamine, bisethylaminobenzophenone, etc. can also be used.

The photosensitive resin composition of the present invention contains a heterocyclic compound having one thiol group as an essential component (e). Such heterocyclic compounds are well known, such as 2-mercapto-
1-methyl-imidazole, 5-amino-1,3,4-
Thiazole-2-thiol, 2-mercapto-benzimidazole, 2-mercapto-benzothiazole, IH
-1,2,4-triazole-3-thiol and the like are used.

The photosensitive resin composition of the present invention comprises the above oligomer (a)
For 11 parts of 100 i, triglycidyl isocyanurate (b) is added to O85 to 10 parts by weight, and amine resin tc+ is added to 1 part by weight.
~30 parts by weight, sensitizer and/or sensitizer system (dl from 1 to
30ii! It is preferable to use the heterocyclic compound Eel having one part ' and one thiol group in a range of 0.05 to 7 parts by weight in order to form a solder mask with excellent resolution, soldering heat resistance, and boiling resistance.

The photosensitive resin composition of the present invention may contain a photopolymerizable unsaturated compound having at least two terminal ethylene groups as a secondary component.

Examples of this unsaturated compound include trimethylolpropane, trimethylolethane, pentaerythritol, dipentaerythritol, 1,3-butylene glycol, 1
．． 4-butylene glycol, 1°5-bentanediol, polycaprolactone diol, polypropylene glycol, decamethylene glycol, glycerin, neopentyl glycol, 2,2-bis[:4,4'-(2-hydroxyethoxy)phenyl]furopane , Tris(2-
Esters of polyhydric alcohols such as hydroxyethyl isocyanuric acid and acrylic acid or methacrylic acid, phthalic anhydride-diethylene glycol-acrylic acid (1/2/2
(mole ratio) condensate, trimethylolpropane-tetrahydrophthalic anhydride-acrylic acid (2/1/4 molar ratio) condensate, etc. Low molecular weight polyester having 7 acryloyloxy groups and/or methacryloyloxy groups at the terminals Examples include resin. Reaction products of diol monoacrylates or diol monomethacrylates and diisocyanates described in Japanese Patent Publication No. 52-43092, etc., diol monoacrylates/dihydric alcohols/diol monoacrylates/dihydric alcohols described in JP-A-57-55914, etc. Trimethylhexamethylene bisocyanate reactant, incyanatoethyl methacrylate/water (2/1 molar ratio) reactant, 1.
A 6-hexanediol diacrylate/monoethanolamine (3/2 molar ratio) reaction product or the like may also be used.

Furthermore, the photosensitive resin composition of the invention may contain a particulate filler.

Examples of fine particulate fillers include talc and silica.

Titanium oxide, clay, calcium carbonate, hydrated silicic acid.

Aluminum hydroxide, alumina, barium sulfate.

Antimony trioxide, magnesium carbonate, mica powder.

Aluminum silicate, magnesium silicate, etc. are used.

The particle size of the particulate filler is preferably 0.01 to 10 μm, more preferably 0.01 to 1.5 μm, from the viewpoint of preventing deterioration of resolution, adhesion of the cured film, and the like. It is preferable that the particulate filler is uniformly dispersed in the photosensitive resin composition. In order to increase the adhesive force between the filler and the photopolymerizable unsaturated compound, the surface of the filler is treated with a silane coupling agent having a functional group such as a hydroxyl group, an amine group, an epoxy group, or a vinyl group. You can also do that. Examples of the silane coupling agent include γ-aminopropyltriethoxysilane, β-aminoethyl-r-aminopropyltrimethoxysilane, r-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, etc. Can be mentioned.

Furthermore, the photosensitive resin composition of the present invention may contain other subsidiary components. Secondary components include thermal polymerization inhibitors such as p-methoxyphenol, benzotriazole, 5-amino-1,3,4-thiadiazole-2-thiol, and 5-mercapto-IH-1,2,4-triazole. adhesion improvers such as

Examples include pigments such as phthalocyanine green, flame retardants such as antimony trioxide, and latent curing agents for epoxy resins.

The photosensitive resin composition of the present invention is prepared using a dip coating method.

A photosensitive layer having a thickness of 10 to 150 μm can be easily formed by directly coating the substrate to be processed and protected by a conventional method such as a roll coating method, a flow coating method, or a screen printing method. When coating, if necessary, the composition can be dissolved in a solvent.

Examples of solvents include methyl ethyl ketone, methyl cellosolve acetate, ethyl cellosolve acetate, cyclohexanone, and methyl cellosolve.

propylene glycol monomethyl ether acetate,
Examples include methylene chloride and propylene glycol monomethyl ether.

Exposure and development of the photosensitive layer thus formed.

It is done in the usual way. That is, using an ultra-high-pressure mercury lamp, high-pressure mercury lamp, or the like as a light source, the layer of the photosensitive resin composition is imagewise exposed directly or through a negative mask through a transparent film such as a polyethylene terephthalate film. If a transparent film remains after exposure, it is peeled off and then developed.

The developer used in the development process is an alkaline aqueous solution, and examples of the base include alkali metal phosphates such as sodium phosphate and potassium phosphate, and alkali metal carbonates such as sodium carbonate. Carbonated)
An aqueous solution of IJum is preferred.

The image-like protective film obtained by the above method has properties as a corrosion-resistant film for ordinary etching, plating, etc., but it can be heated at 80 to 200°C after development to improve adhesion. It can improve properties such as hardness, heat resistance, and solvent resistance.
A permanent protective film that satisfies the properties of a solder mask is obtained.

(Example) Next, the present invention will be explained in detail based on examples.

The present invention is not limited to this. Table o.

In the example, “division” is 4! means "parts by weight" unless otherwise specified.

Example 1 (Synthesis of al oligomer (1) Epicor) 152 (manufactured by Shell, 175 parts phenol novolak type epoxy resin, epoxy equivalent: 175) Propylene glycol monomethyl 40 parts Ether acetate B, acrylic acid 54 parts p-quinone 0.1 0.3 parts Penzyl triethyl ammonium chloride 116 parts Rum C0 Tetrahydrophthalic anhydride 170 parts Propylene glycol monomethyl , add the above person, 1
1 while keeping the reaction temperature at 110°C.
B was evenly added dropwise over time. After dropping B, 110℃
After stirring was continued for about 10 hours to reduce the acid value of the reaction system 9 to 1 or less, the mixture was cooled to 60° C. and C was added. After dropping C, about 2
The temperature was raised to 110°C over a period of time, and stirring was continued at 110°C for about 10 hours to bring the acid value of the 9 reaction system to 61, yielding an oligomer solution (1) with a nonvolatile content of 69% by weight.

(bl) Preparation of photosensitive resin composition (a) + 11,109 parts of the oligomer solution obtained in (a) (75 parts of non-volatile content), Cymel 300 (trade name of melamine resin manufactured by Mitsui Toatsu Cymel Co., Ltd.), 10 parts, 2-metal f roux 1-
C4-C methylthio)phenyl]-2-morpholino-propane-1,7 parts, 2-isopropylthioxanthone 1
0.2 parts of 5-amino-1,3°4-thiadiazole-2-thiol and 10 parts of propylene glycol monomethyl ether were blended and uniformly dissolved, and TEPI
A solution of the photosensitive resin composition of the present invention was prepared by uniformly dispersing 2 parts of C-8 (trade name of triglycidyl isocyanurate manufactured by Nichichi Kagaku Kogyo ■).

(Formation of C1 cured film (bl) The solution of the photosensitive resin composition obtained in BL was applied to a steel-clad laminate, and dried at room temperature for 20 minutes and at 80°C for 20 minutes to form a photosensitive layer with a thickness of 40 μm. did.

Next, the film was exposed to light at 400 mJ/C- through a negative mask using a Phoenix 3000 type exposure machine manufactured by Oak Manufacturing Co., Ltd. After exposure, heat at 80°C for 5 minutes.

After being left at room temperature for 30 minutes, it was spray developed using a 1% aqueous sodium carbonate solution at 30°C for 60 seconds.

Immediately sprayed and washed with water for 60 seconds. Next, heat treatment was performed at 150° C. for 30 minutes to obtain a solder mask with excellent dimensional accuracy corresponding to a negative mask. This solder mask has excellent soldering heat resistance after absorbing moisture, and after being immersed in boiling water for 1 hour, it is soldered using rosin-based Frank A-226 (manufactured by Memura Kaken).
Even after soldering at 0° C. for 60 seconds, no peeling or blistering of the mask was observed. Furthermore, this solder mask had excellent solvent resistance, and no swelling or peeling of the film was observed even when immersed in a mixed solvent of methylene chloride/methanol (3/lli ratio) at 25° C. for 10 minutes. Moreover, this photosensitive resin composition had excellent storage stability and was stable for 3 weeks or more at 40°C.

Example 2 (Synthesis of al oligomer) Epicoat 154 (manufactured by Shell, 178 parts phenol novolak type epoxy resin, epoxy equivalent: 178) Propylene glycol monomethyl 40 parts Ether acetate B, acrylic acid 72 parts p-quinone 0.1 part Penzyl chloride Triether ammonia 0.3 parts Rum C0 Tetrahydrophthalic anhydride 50 parts Propylene glycol monomethyl 170 parts Using ether acetate A-C, otherwise 9 in the same manner as in Example 1(a)
Acid value of reaction system: 38. A solution of the oligomer (Ill) with a non-volatile content of 59% by weight was obtained.

(bl Solution of oligomer obtained in preparation (a) of photosensitive resin composition (I [1127 parts (
Non-volatile content 75 parts), Cymel 325 (trade name of melamine resin manufactured by Mitsui Toatsu Cymel Co., Ltd.), 10 parts, 2-methyl-1
-(4-(methylthio)phenylcou 2-morpholino-
1,7 parts of propanone, 1 part of 4,4'-bisdiethylaminobenzophenone, 0.2 parts of 5-amino-1,3,4-thiadiazole-2-thiol, and 10 parts of propylene glycol monomethyl ether were mixed uniformly. A solution of the photosensitive resin composition of the present invention was prepared by dissolving and uniformly dispersing 85 parts of TEPIC. Thereafter, a cured film with excellent heat resistance was obtained in the same manner as in Example 1(d). Furthermore, this photosensitive resin composition had excellent storage stability as well as in Example 1.

Example 3 [a) Synthesis of oligomer Epicote 152 175 parts Propylene glycol monomethyl 40 parts Ether acetate B, acrylic acid 54 parts p-quinone 0.1 part Benzyltriethylammochloride 0.3 part Niumium CO maleic anhydride 75 parts Propylene Glycol monomethyl 17 (1 Using ether acetate A-C, otherwise 9 in the same manner as in Example 1(a))
Acid value of reaction system: 57. An oligomer solution (■) with a nonvolatile content of 59 tS was obtained.

(b) Preparation of the photosensitive resin composition The solution of the oligomer obtained in (a) (127 parts (non-volatile content 75 parts)), the solution of the epoxy group-containing unsaturated compound obtained in (bl) ([1125 parts ( 10 parts non-volatile).

APG700 (Shin Nakamura Chemical polypropylene glycol diacrylate) 10 parts, 2-methyl-1-II:4-
(Methylthio)phenyl]-2-morpholino-propanone-1,7 parts, 4-diethylthioxanthone 1 part, 5
- 0.1 part of amino-1,3,4-thiadiazole-2-thiol and 10 parts of propylene glycol monomethyl ether were blended and uniformly dissolved, and TEPIC-8
One part was uniformly dispersed to obtain a solution of the 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(d).

Example 4 (Al Synthesis of oligomer (a) A, BREN (Nippon Kayaku ■, halogen 280 parts phenol novolak type epoxy [280]) Propylene glycol monomethyl 6 (1 ether acetate B, acrylic acid 72 parts p-quinone o , Part i Benzyltriethylammochloride 0.3 parts Nium salt C0 Methylhydrophthalic anhydride 166 parts Propylene glycol monomethylene 200 parts Using ether acetate A-C, otherwise 9 in the same manner as in Example 1(a)
Acid value of reaction system: 72. An oligomer solution (IV) with a nonvolatile content of 67% by weight was obtained.

fbl Preparation of photosensitive resin composition (37 parts of oligomer solution (IV) obtained in al (25 parts of non-volatile content), 72 parts of oligomer solution (1) obtained in Example 1(a) (non-volatile content) 50 copies L TEPIC-
81 parts, antimony trioxide 2 parts, Micro Ace P-4 (
A filler dispersion was prepared by blending 10 parts of talc manufactured by Nippon Talc (average particle size: 1.5 μm) and 1 part of phthalocyanine green using a triple roll.

Next, 2-methyl-[4-(methylthio)phenyl]-
2-morpholino-propanone-1.7 parts.

1 part 2-isopropylthioxanthone, 5-amino-1
, 0.2 parts of 3,4-thiadiazole-2-thiol and 30 parts of propylene glycol monomethyl ether were stirred and dissolved.Next, 115 parts of the above filler dispersion was blended and stirred and dispersed to obtain the photosensitive resin composition of the present invention. I got something. Thereafter, a cured film with excellent heat resistance was obtained in the same manner as in Example 1(C).

Comparative Examples 1 to 3 Triglycidyl isocyanurate Cynor 300.5-amino-1,
With the exception of 3,4-thiadiazole-2-thiol,
Photosensitive resin compositions of Comparative Examples 1 to 3 were prepared, and Example 1 (
A cured film with a thickness of 40 μm was formed on the copper-clad laminate in the same manner as in C). but.

All of the obtained cured films had poor soldering heat resistance after moisture absorption, and after being immersed in boiling water for 1 hour, rosin-based flux A226
When soldering was carried out at 260° C. for 20 seconds using the same method, blistering occurred.

Comparative Example Comparative Example Comparative Example Oligomer obtained in Example 1(a) 75 parts Same as left
Same as on the left (non-volatile content) Holinopropanone-1 Isopropylthioxanthone 1 part Same as on the left Same as on the left 5-Amino-1,&4-thiasia 0.2 parts -0,2
-2 parts Sol-2-thiol triglycidyl isocyanurate -2 parts Same as left Cymel 300 10 parts 10 parts As is clear from the examples 9, by using the photosensitive resin composition of the present invention, it is possible to form thick film images by photography. It is possible! A highly reliable solder mask with excellent resolution and heat resistance can be formed using an alkaline earth metal.

(Effect of the invention) By using the photosensitive resin composition of the present invention.

It is possible to form a highly reliable solder mask that can be developed with an alkaline aqueous solution that is safe and economical, and has excellent resolution and heat resistance when absorbing moisture.

Claims (1)

[Claims] 1. (a) an oligomer having a carboxyl group and a photoreactive unsaturated group in its side chain and being soluble in an alkaline aqueous solution, (b) triglycidyl isocyanurate, (c) an amino resin, A photosensitive resin composition comprising (d) a sensitizer and/or a sensitizer system that generates free radicals upon irradiation with actinic rays, and (e) a heterocyclic compound having one thiol group. 2. The oligomer having a carboxyl group and a photoreactive unsaturated group in the side chain and being soluble in an alkaline aqueous solution is a group consisting of orthocresol novolac type epoxy resin, phenol novolak type epoxy resin, and halogenated phenol novolac type epoxy resin. A secondary hydroxyl group of an unsaturated compound obtained by addition reacting at least one novolak type epoxy resin selected from the following with an unsaturated carboxylic acid at an acid equivalent/epoxy equivalent ratio in the range of 0.5 to 1.05 The photosensitive resin composition according to claim 1, which is an oligomer obtained by reacting residual epoxy groups with a saturated or unsaturated polybasic acid anhydride. 3. The photosensitive resin composition according to claim 1 or 2, wherein the amino resin is a melamine resin. 4. The photosensitive resin composition according to claim 1 or 2, wherein the amino resin is hexamethoxymethylmelamine.