JPH03182755A - Liquid photosensitive resin composition - Google Patents

Abstract

PURPOSE:To provide a high sensitivity to exposing with UV rays and to improve the developability by an aq. alkaline soln. by incorporating a novolak type epoxy compd., a photopolymerizable compd. obtd. from a polybasic acid anhydride, etc., and a photopolymn. initiator into the above compsn. CONSTITUTION:The novolak type epoxy compds., the photopolymerizable compd. which is obtd. by successively bringing the (meth)acrylate half esterified matter having the hydroxyl group of the dibasic acid in the form of the acid anhydride or forming a 4-membered ring or 6- to 15-membered ring in the case of assumption of acid anhydride skeleton and if necessary, (meth)acrylic acid and the polybasic acid anhydride into reaction and the photopolymn. initiator are incorporated into the liquid photosensitive resin compsn. Thus, the high sensitivity to the exposing with the UV rays and the excellent developability by the aq. alkaline soln. are obtd. and the change in the developability with the lapse of time is lessened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a liquid photosensitive resin composition. More specifically, it can be used to form permanent protective masks such as solder resists for manufacturing printed wiring boards, is highly sensitive to ultraviolet exposure, has excellent developability with alkaline aqueous solutions, and has little change in developability over time. Furthermore, the present invention aims to create a liquid photosensitive resin composition that has excellent electrical properties, mechanical properties, and chemical resistance of the coating film after curing.

(Prior art) Conventionally, in the printed wiring board industry, resin compositions used for permanent protective masks such as solder resists and chemical plating resists are mainly composed of thermosetting resins such as epoxy resins and melamine resins. For pattern formation,
Screen printing methods have been widely used. The main purpose of solder resist is to limit the soldering area, prevent solder bridges, prevent corrosion of conductors, and maintain electrical insulation between conductors over a long period of time. .

In recent years, with the high-density packaging of VLSIs, etc., there has been a demand for smaller conductor spacing, as well as stricter requirements for electrical insulation between conductors, and solder resists with excellent dimensional accuracy are now required. It has become.

However, screen printing methods inherently have low resolution, and phenomena such as smearing, pinholes (for high viscosity inks) or bleeding, smearing, and dripping (for low viscosity inks) occur, and the high density of printed wiring boards It is becoming impossible to respond to

Therefore, the photographic method (forming an image by image exposure followed by development)
Photosensitive resin compositions that can form patterns with high sensitivity, high resolution, and have excellent electrical and mechanical properties of the cured coating are currently attracting attention.

Dry film type or liquid developable photosensitive resin compositions have been developed as permanent protective masks for printed wiring boards whose patterns are formed by photography.

As a dry film type photosensitive resin composition, for example,
Urethane di(meth) in JP-A No. 57-55914 etc.
A photosensitive resin composition comprising an acrylate, a linear polymer compound, and a photosensitizer is also disclosed in JP-A-62-24735.
No. 3 discloses a photosensitive resin composition comprising a (meth)acrylic modified resin of a specific novolac epoxy resin and a photosensitizer.

However, in general, in the case of a dry film type photosensitive resin composition, bubbles are likely to be generated during heat and pressure bonding, and there are concerns about heat resistance and adhesion. In order to solve these problems, a special process such as heat-compression bonding under reduced pressure is required, as disclosed in Japanese Patent Application Laid-Open No. 52-52703, etc., but even if such a process is used, , complete heat resistance and adhesion are not guaranteed.

On the other hand, liquid developable photosensitive resin compositions require fewer steps because they are applied directly to printed wiring boards in liquid form immediately before use, and because they are liquid, they are also suitable for printed wiring boards with severe unevenness. It can form an excellent image and is suitable, for example, as a photosensitive resin composition for permanent protective masks for printed wiring boards with narrow conductor spacing.

However, this liquid photosensitive resin composition also has the disadvantage that, after being applied onto a printed wiring board, if the pattern mask is brought into direct contact with the coating surface and exposed to light, the pattern mask becomes dirty.

As a method for solving this pattern mask stain, as disclosed in Japanese Patent Laid-Open No. 57-164595, etc., the coating surface and the pattern mask are placed with a gap between them, and the uncured liquid is cured by exposure. There are special methods for removing photosensitive resin compositions. However, as a result of increasing the distance between the coating surface and the pattern mask, there are disadvantages such as poor resolution and the need for special equipment, which increases the cost.

In addition, Japanese Patent Application Laid-open Nos. 58-24144, 59-2049, 61-102652, and 62-27736,
A method of manufacturing a solder resist using a transparent flexible support or patterned mask is disclosed. However, these methods also have problems such as requiring specific equipment and being expensive.

Furthermore, in the method described above in which the liquid photosensitive composition is directly exposed to light according to the resist pattern without drying, the liquid photosensitive composition uses a liquid prepolymer containing a large number of reactive monomers, so the liquid photosensitive composition has acid resistance. There is also the problem that properties such as chemical resistance are inferior to conventional methods.

Therefore, a method is usually used in which a liquid photosensitive resin is applied, then heated and dried, exposed to light with a pattern mask in close contact with the resin, and developed to form a solder resist.

An example of this is a liquid resin composition whose main component is a bisphenol type epoxy resin having an unsaturated group and a carboxyl group, as disclosed in JP-A-62-187722.

Furthermore, in recent years, due to problems such as work environment, air and water pollution, photosensitive resin compositions that can be developed with alkaline aqueous solutions or water have been desired. An example of this is the Japanese Unexamined Patent Publication No. 6
Liquid resist ink containing a photopolymerizable compound obtained by reacting a novolac type epoxy compound, an unsaturated monocarboxylic acid, and a polybasic acid anhydride, as disclosed in Publications No. 1-243869 and No. 63-258975, etc. There is a composition.

However, in these liquid photosensitive resin compositions, the photopolymerizable compound obtained by reacting the epoxy resin, which is the main component, has low sensitivity compared to ordinary photopolymerizable monomers.
Exposure time takes longer and workability decreases. Alternatively, there are problems such as damage to the photomask due to temperature rise during exposure.

Therefore, in order to solve these problems, we
No. 253729 discloses a liquid photosensitive resin composition using a photopolymerizable compound obtained by sequentially reacting a novolac type epoxy compound, a (meth)acrylate half-ester having a hydroxyl group of a dibasic acid, and a polybasic acid anhydride. is proposed. However, the molecular weight of these photopolymerizable compounds may progress during synthesis or over time, and therefore liquid photosensitive resin compositions using these photopolymerizable compounds may have poor developability. . Further, similar descriptions of photopolymerizable compounds can be found in JP-A-1-141904, but there is no particular mention of the effects of using these photopolymerizable compounds. Further, in all cases, only examples are shown in which the dibasic acid of the (meth)acrylate half-esterified product having a hydroxy group of the dibasic acid forms a five-membered ring in the form of an acid anhydride.

(Problems to be Solved by the Invention) The purpose of the present invention is to solve the above-mentioned conventional technical problems and to provide a solution to ultraviolet light exposure using a photopolymerizable compound that can suppress polymerization during synthesis and/or over time. Liquid photosensitivity with high sensitivity when engraving, excellent developability with alkaline aqueous solutions, little change in developability over time, and excellent electrical properties, mechanical properties, and chemical resistance of the coating film after curing. An object of the present invention is to provide a resin composition.

(Means for Solving the Problems) The present inventors have discovered that the above problems can be solved by using the following liquid photosensitive resin composition, and have arrived at the present invention.

That is, the object of the present invention is to at least form a 4-membered ring or a 6- to 15-membered ring when (1) (1) a novolak-type epoxy compound and (2) assume the form of an acid anhydride or an acid anhydride skeleton. A photopolymerizable compound obtained by sequentially reacting a (meth)acrylate half-esterified product having a hydroxyl group of a dibasic acid, optionally (meth)acrylic acid, and (3) a polybasic acid anhydride; This was achieved by a liquid photosensitive resin composition characterized by containing a polymerization initiator.

The photopolymerizable compound used in the composition of the present invention is 1) a novolac-type epoxy compound and 2) forms an acid anhydride, or forms a 4-membered ring or a 6- to 15-membered ring when an acid anhydride skeleton is assumed. It is obtained by sequentially reacting a (meth)acrylate half-ester having a hydroxyl group of a dibasic acid, optionally (meth)acrylic acid, and 3) a polybasic acid anhydride.

Typical novolak-type epoxy compounds include:
There are phenol novolac type epoxy resins, cresol novolac type epoxy resins, and halogenated phenol novolac type epoxy resins. These are obtained by reacting epichlorohydrin in the presence of an alkali with the phenolic hydroxyl group of a novolac type resin obtained by reacting phenol, cresol, halogenated phenol, etc. with an aldehyde in the presence of an acid catalyst.

4 when assuming the form of acid anhydride or acid anhydride skeleton
A semi-esterified product of acrylate (meth) having a hydroxy group of a dibasic acid forming a membered ring or a 6- to 15-membered ring is, for example, a dibasic acid or its anhydride and a hydroxy group (
Obtained as an equimolar reaction product of meth)acrylate. This dibasic acid or its anhydride needs to form a 4-membered ring or a 6- to 15-membered ring when an acid anhydride form or an acid anhydride skeleton is assumed. Specific examples of such include malonic acid, glutaric acid, adipic acid, pimelic acid, superric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, l.
, 11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, methylmalonic acid, ethylmalonic acid, 2-
Methylglutaric acid, 3-methylglutaric acid, 3.3-tetramethyleneglutaric acid, 1. Examples include 1-cyclobutanedicarboxylic acid, glutaconic acid, diglycolic acid, thiodiglycolic acid, glutaric anhydride, 3,3-tetramethyleneglutaric anhydride, diglycolic anhydride, thiodiglycolic anhydride, and the like. Among these, particularly preferred specific examples include glutaric anhydride, 3,3-tetramethyleneglutaric anhydride, diglycolic anhydride, and the like.

If a dibasic acid or its anhydride that forms a 5-membered ring in the form of an acid anhydride, such as succinic acid, maleic acid, or phthalic acid, is used, the molecular weight increases during synthesis or over time as described above. This progresses and causes a decline in developability.

The reason for this is unknown, but the present inventors found that the hydroxyl group of the dibasic acid forms a 5-membered ring in the form of an acid anhydride (
In the case of meth)acrylate half-esterified products, the production of acid anhydrides in the equilibrium reaction progresses rapidly, and the produced acid anhydrides act as a crosslinking agent, resulting in polymerization during the synthesis of photopolymerizable compounds or over time. It is assumed that this is progressing.

On the other hand, (meth)acrylates having a hydroxy group include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meta)
Acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxy-3-chloropropyl (meth)acrylate, diethylene glycol mono(meth)acrylate, 2-methacryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenyl Oxypropyl (meth)acrylate, glycerinone di(meth)acrylate, trimethylolbroban di(meth)acrylate, pentaerythritol tri(meth)
Examples include acrylate. Among these, particularly preferred specific examples include 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate.

An equimolar reaction product of a dibasic acid forming a 4-membered ring or a 6-15-membered ring and a (meth)acrylate having a hydroxyl group in the form of an acid anhydride as described above, or assuming an acid anhydride skeleton. Particularly preferred specific examples of the products include equimolar reaction products of glutaric anhydride and 2-hydroxyethyl (meth)acrylate, and equimolar reaction products of glutaric anhydride and 2-hydroxypropyl (meth)acrylate. .

In addition, as polybasic acid anhydrides, succinic anhydride, methylsuccinic anhydride, 2,3-dimethylsuccinic anhydride, 2-dimethylsuccinic anhydride,
, 2-dimethylsuccinic acid, ethylsuccinic anhydride, dodecenylsuccinic anhydride, nonenylsuccinic anhydride, maleic anhydride, methylmaleic anhydride, 2,3-dimethylmaleic anhydride, 2-chloromaleic anhydride, 2,3-dichloroanhydride Maleic acid, bromomaleic anhydride, itaconic anhydride, citraconic anhydride, cis-acottic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride , methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, chlorendic anhydride, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1, 2-dicarboxylic acid anhydrides and dibasic acid anhydrides such as glutaric anhydride, trimellitic anhydride, 3.
3', 4. Polybasic acid anhydrides such as 4'-benzophenonetetracarboxylic acid can be used. Among these, preferred are the dibasic acid anhydrides listed above, with succinic anhydride and tetrahydrophthalic anhydride being particularly preferred.

Each is reacted sequentially to obtain a photopolymerizable compound,
The ratio in which they are reacted is 1) 1 equivalent of the epoxy group of the novolac type epoxy compound to 2> acid anhydride form, or a 4-membered ring or a 6- to 6-membered ring when assuming an acid anhydride skeleton.
It has a dibasic acid hydroxyl group forming a 15-membered ring (
meth)acrylate half ester and optionally (
The total amount of meth)acrylic acid is 0. 5 to 1.2 equivalents, preferably 0.8 to 1.1 equivalents, and 3) polybasic acid anhydride 0.1 to 1.1 equivalents, preferably 0.1 to 1.1 equivalents. 3-1.
It is 0 equivalent. A (meth)acrylate half-esterified product having a hydroxy group of a dibasic acid that forms an acid anhydride or a 4-membered ring or a 6- to 15-membered ring assuming an acid anhydride skeleton, and optionally (meth) ) If the total amount of acrylic acid is less than 0.5 equivalent, a decrease in sensitivity and gelation of the resin will occur.1. If more than 2 equivalents are used, tack problems will occur.

Moreover, polybasic acid anhydride is 0. If the amount is less than 1 equivalent, the developability will deteriorate, and if it exceeds 1.1 equivalents, problems such as tackiness and precipitation of crystals will occur. In addition, a (meth)acrylate half-esterified product having a hydroxy group of a dibasic acid that forms a 4-membered ring or a 6- to 15-membered ring when an acid anhydride form or an acid anhydride skeleton is assumed, and if necessary used (
The molar ratio of meth)acrylic acid is 100:0-10:9
0, preferably 100:0 to 25:75.
When the molar ratio of (meth)acrylic acid is 90 or more, sensitivity decreases.

These photopolymerizable compounds may be used alone or in combination of two or more.

Examples of photopolymerization initiators include α-diketones such as benzyl and diacetyl, acyloins such as benzoin, acyloin ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, thioxanthone, and 2,4-diethylthioxanthone. , thioxanthone-1-sulfonic acid, thioxanthone-
Thioxanthone such as 4-sulfonic acid, benzophenone, 4,4'-bis(dimethylamino)benzophenone,
Benzophenones such as 4,4"-bis(diethylamino)benzophenone, acetophenone, p-dimethylaminoacetophenone, α,α' dimethoxyacetoxyacetophenone, 2,2'-dimethoxy-2-phenylacetophenone, p-methoxyacetophenone, 2- Acetophenones such as methyl-[4-(methylthio)phenyl-2-morpholino-1-propanone, anthraquinone, quinones such as 1,4-naphthoquinone, phenacyl chloride, tribromomethylphenylsulfone, tris(trichloromethyl)- Examples include halogen compounds such as S-triazine, and peroxides such as di-t-butyl peroxide.

These photopolymerization initiators may be used alone or in a mixture of two or more, and the amount of these photopolymerization initiators is 0.08 to 30% relative to the photopolymerizable compound.
It is preferable to use 0.15 to 15 parts by weight. If it is less than 0.08 parts by weight, the sensitivity will decrease, and if it exceeds 30 parts by weight, precipitation of crystals, insufficient hardening of the lower part, etc. will occur.

The liquid photosensitive resin composition of the present invention contains, in addition to the above-mentioned photopolymerizable compound and photopolymerization initiator, a polymerizable compound having at least one ethylenically unsaturated double bond and at least one epoxy group. It is preferable to add a thermosetting catalyst, an organic solvent, a thermal polymerization inhibitor, etc., which causes the epoxy group to undergo a thermal reaction.

Examples of the polymerizable compound having at least one ethylenically unsaturated double bond include esters of acrylic acid or methacrylic acid of monohydric or polyhydric alcohols.

Monohydric or polyhydric alcohols such as esters of acrylic acid or methacrylic acid include methanol, ethanol, propatool, isopropyl alcohol, n-butanol, isobutanol, t-butanol, cyclohexyl alcohol, benzyl, etc. Alcohol, octyl alcohol, 2-ethylhexanol, lauryl alcohol, n-decanol, undecanol, cetyl alcohol, stearyl alcohol, methoxyethyl alcohol, ethoxyethyl alcohol/butoxyethyl alcohol, polyethylene glycol monomethyl ether, polyethylene glycol monoethyl ether,
2-hydroxy-3-chloropropane, dimethylaminoethyl alcohol, diethylaminoethyl alcohol,
Glycidol, 2-trimethoxysilylethanol, ethylene chlorohydrin, ethylene bromohydrin, 2,
Examples include 3-dibromopropanol, allyl alcohol, oleyl alcohol, epoxystearyl alcohol, phenol, naphthol, and the like. Examples of polyhydric alcohols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, and l.

5-bentanediol, hexanediol, heptanediol, octanediol, nonanediol, dodecanediol, neopentyl glycol, 1.10-decanediol, 2-butene-1,4-diol, 2-n-butyl-2-ethyl Propanediol, cyclohebutanediol, 1. 4-cyclohexane dimetatool, 3-
Cyclohexene-1,1-jetanol, polyethylene glycol (diethylene glycol, triethylene glycol, etc.), polypropylene glycol (dipropylene glycol, tripropylene glycol, etc.), polystyrene oxide glycol, polytetrahydrofuran glycol, xylylene diol, bis(β-hydroxyethoxy ) Benzene, 3-chloro-1,2-propanediol, 2,2-dimethyl-1,3-propanediol,
2,2-diethyl-1,3-propanediol, 2,2
-diphenyl-1,3-propanediol, decalindiol, 1,5-dihydroxy-1,2,3゜4-tetrahydronaphthalene, 2,5-dimethyl-2,6-hexanediol, 2-ethyl-1゜3 -hexanediol, 2-ethyl-2-(hydroxymethyl)-1,3-propanediol, 2-ethyl-2-methyl-1,3-propanediol, 3-hexene-2,5-diol, hydroxybenzyl alcohol , 2-methyl-1,4-butanediol, 2-methyl-2,4-bentanediol, 1-phenyl-1,2-ethanediol, 2, 2.
4. 4-tetramethyl-1,3-cyclobutanediol, 2. 3. 5. 6-tetramethyl-p-xylene-α,α′-diol, 1°4.4-tetraphenyl-2-butyne-1,4-diol, 1,1′-bi-2-naphthol, dihydroxynaphthalene, 1. P-
Methylene-di-2-naphthol, biphenol, 2.2
-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(
hydroxyphenyl)methane, catechol, resorcinol, 2-methylresorcinol, 4-chlororesorcinol, pyrogallol, α-(1-aminoethyl)-p
-Hydroxybenzyl alcohol, 2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl-1°3-propanediol, 3-amino-1,2
-Propanediol, N-(3-aminopropyl)-diethanolamine, N, N-bis(2-hydroxyethyl)piperazine, 1,3-bis(hydroxymethyl)urea, 1,2-bis(4-pyridyl)- 1,2-ethanediol, N-n-butylgetanolamine, jetanolamine, N-ethylgetanolamine, 3
-Mercap)-1゜2-propanediol, 3-piperidine-1,2-propanediol, 2-(2-pyridyl)-1゜3-propanediol, α-(l-aminoethyl)-p-hydroxybenzyl Alcohol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, sorbitol, glucose, α-
Mannitol, butanetriol, 1. 2. 6-)
Lihydroxyhexane, 1, 2. Examples include 4-benzenetriol, triethanolamine, 2,2-bis(hydroxymethyl)-2,2',2''-nitrilotriethanol, etc.Acrylic acid or methacrylic acid esters of these monohydric or polyhydric alcohols Among them, ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, Dipentaerythritol hexamethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, glycerin triacrylate, glycerin trimethacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, trimethylolethane triacrylate, trimethylolethane trimethacrylate , neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, sorbitol hexaacrylate, sorbitol hexamethacrylate, sorbitol pentaacrylate, sorbitol pentamethacrylate and the like are preferred.

It is also possible to use mono- or polyamine acrylamide or methacrylamide. Examples of monoamines include monoalkylamines such as ethylamine, butylamine, amylamine, hexylamine, octylamine, cyclohexylamine, and 9-aminodecalin; monoalkenylamines such as allylamine, metaallylamine, and benzylamine; and aniline, toluidine, Aromatic amines such as p-7 minostyrene are mentioned. Examples of polyamines include ethylene diamine, trimethylene diamine, tetramethylene diamine, hexamethylene diamine, octamethylene diamine, hexamethylene bis(2-aminopropyl) amine, diethylene triamine, triethylene tetraamine, polyethylene polyamine, tris(2-amino ethyl)amine, 4,4'-methylenebis(cyclohexylamine), N,N'-bis(2-aminoethyl)-
1,3-propanediamine, N,N'bis(3-aminopropyl)-1,4-butanediamine, N,N'-bis(3-aminopropyl)ethylenediamine, N,N'-
Bis(3-aminopropyl)-1,3-propanediamine, 1,3-cyclohexanebis(methylamine), phenylenediamine, xylylenediamine, β-(4-aminophenyl)ethylamine, diaminotoluene, diaminoanthracene, diamino Examples include naphthalene, diaminostyrene, methylene dianiline, 2,4-bis(4-aminobenzyl)aniline, and aminophenyl ether.

Furthermore, allyl compounds such as formic acid, acetic acid, propionic acid, butyric acid, lauric acid, benzoic acid, chlorobenzoic acid, malonic acid, oxalic acid, glutaric acid, adipic acid, sebacic acid, phthalic acid, terephthalic acid, hexahydrophthalic acid ,
Mono- or polyallyl esters of mono- or polycarboxylic acids such as chlorendic acid and trimellitic acid, mono- or polyallyl esters of mono- or polysulfonic acids such as benzenedisulfonic acid, naphthalenedisulfonic acid, diallylamine, N,N'-diallyl Oxalic acid diamide, 1
, 3-diallylurea, diallyl ether, triallyl isocyanurate, etc. can also be used.

Also, for example, divinylbenzene, p-allylstyrene,
Polyvinyl compounds such as p-isopropenyl styrene, divinyl sulfone, ethylene glycol divinyl ether, glycerol trivinyl ether, divinyl phthalate, divinyl phthalate, divinyl terephthalate, etc., 2
Acrylic acid or methacrylic acid ester compounds having an ionic group such as -hydroxy-3-methacryloyloxypropyltrimethylammonium chloride and methacryloyloxyphenyltrimethylammonium chloride can also be used.

Furthermore, commercially available polymerizable monomers or oligomers such as Aronix M5700 and M6 manufactured by Toagosei Chemical Industry Co., Ltd.
100, M8O30, M152, M2O3, M215,
Acrylate monomers such as M315 and M325 NK ester ABPE-4 and U-4H manufactured by Shin-Nakamura Chemical Industry Co., Ltd.
A, CB-1, CBX-1, KAYARA manufactured by Nippon Kayaku Co., Ltd.
D ReO4, DPCA-30, DPCA-60, K
Acrylate or methacrylate monomers such as AYAMAR PM-1, PM-2, and Photomer 4061.5007 manufactured by San Nobuco Co., Ltd. Lipoxy VR6 manufactured by Showa Kobunshi Co., Ltd.
Epoxy acrylates such as 0, VR90, and 5P1509, and spirane resins having a spiroacetal structure and an acrylic or methacrylic group such as Subirac E-4000X and U3000 manufactured by the same company, etc., can also be used.

These compounds may be used alone or in combination of two or more.

As a compound having at least one epoxy group,
For example, glycidyl ethers of alcohols having 2 to 20 carbon atoms such as butyl glycidyl ether, octyl glycidyl ether, decyl glycidyl ether, aryl glycidyl ether, phenyl glycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, ethylene glycol diglycidyl Ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanesiol diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, diglycerol tetraglycidyl ether , polyglycidyl ethers of polyols such as polyglycerol polyglycidyl ether, 2,6-sibricidylphenylglycidyl ether, 2. 6. 2', 6'-tetramethyl-4,4'-biphenyl diglycidyl ether, bisphenol A epoxy resin, hydrogenated bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol F epoxy resin, bisphenol Glycidyl ether type epoxy compounds such as S type epoxy resin, hydrogenated bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, halogenated phenol novolac type epoxy resin and brominated epoxy resin, alicyclic gel Cycloaliphatic epoxy compounds such as poxyacetal, alicyclic jepoxy adipate and vinylcyclohexene dioxide, glycidyl acrylate, glycidyl methacrylate, tetrahydroxyphthalic acid diglycidyl ester, sorbic acid glycidyl ester, oleic acid glycidyl ester and lyluic acid glycidyl ester unsaturated acid glycidyl esters such as butyl glycidyl ester, octyl glycidyl ester, alkyl carboxylic acid glycidyl esters such as hexahydrophthalic acid diglycidyl ester and dimer acid glycidyl ester, benzoic acid glycidyl ester, O-phthalic acid diglycidyl ester and glycidyl ester-type epoxy compounds such as aromatic carboxylic acid glycidyl esters such as diglycidyl p-oxybenzoic acid, tetraglycidyldiaminodiphenylmethane, triglycidyl-p-aminophenol, triglycidyl-m-aminophenol, diglycidylaniline, Glycidyltoluidine, tetraglycidyl-m-
Glycidylamine-type epoxy compounds such as xylylene diamine, diglycidyltribromoaniline and tetraglycidylbisaminomethylcyclohexane, heterocyclic epoxy compounds such as diglycidylhydantoin, glycidylglycidoxyalkylhydantoin and triglycidyl isocyanurate, etc. It will be done. Among these, 2,6.2'6-tetramethyl-4,4'-biphenyl diglycidyl ether, novolak type epoxy resin,
Heterocyclic epoxy compounds are preferred.

These epoxy compounds may be used alone or in combination of two or more.

Thermosetting catalysts for thermally reacting epoxy groups include diethylenetriamine, triethylenetetramine, tetraethylenehentamine, iminobisbutylamine (dipropyltriamine), bis(hexamethylene)triamine, 1. 3. 6-) Polyamines such as risaminomethylhexane, polymethylene diamines such as trimethylhexamethylene diamine, polyether diamine, diethylaminoprobylamine, menthene diamine, isophorone diamine, bis(4-amino-3-methyl aliphatic primary amines such as alicyclic polyamines such as cyclohexyl)methane and N-aminoethylpiperazine; aromatic primary amines such as metaphenylenediamine, diaminophenylmethane, diaminophenyl sulfone and aromatic diamine eutectic mixtures; , polyamine epoxy resin adduct,
Polyamine-ethylene oxide duct, polyamine-
Modified amines such as propylene oxide adducts, cyanoethylated polyamines, ketoimines, tertiary amines such as piperidine, piperazine, morpholine, and tetramethylguanidine, triethanolamine, benzyldimethylamine, 2. 4. amine compounds such as tertiary amines such as 6-tris(dimethylaminomethyl)phenol;
Phthalic anhydride, trimellitic anhydride, ethylene glycol bis(anhydrotrimellitate), glycerin tris(anhydrotrimellitate), pyromellitic anhydride, 3. 3', 4. Aromatic acid anhydrides such as 4'-benzophenonetetracarboxylic anhydride, maleic anhydride, succinic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride , cyclic aliphatic acid anhydrides such as alkenylsuccinic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylcyclohexenetetracarboxylic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic anhydride, etc. aliphatic acid anhydrides, and acid anhydrides such as chlorendic anhydride, halogenated acid anhydrides such as tetrabromophthalic anhydride, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-
Undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, ]-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl- 2-undecylimidazole, l-cyanoethyl-2-undecylimidazolium trimellitate, l-cyanoethyl-2-phenylimidazolium trimellitate, 2-methylimidazolium isocyanurate, 2-phenylimidazolium isocyanurate, 2,4-diamino-6-[
2-Methylimidazolyl-(1)]-]ethyl-8-triazine2,4-diamino-6-[2-ethyl-4-methylimidazolyl-(1)]-]ethyl-5-riazine, 2,4-diamino- 6-[2-undecylimidazolyl-(1)]-]ethyl-8-triazine 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2
-Phenyl-4,5-dihydroxymethylimidazole, 1-cyanoethyl-2-phenyl-4,5-di(cyanoethoxymethyl)imidazole, 1-dodecyl-2-
Imidazole compounds such as methyl-3-benzylimidazolium chloride and 1,3-dibenzyl-2-methylimidazolium chloride, phenols such as novolak-type phenolic resin, cresol-type phenolic resin, resorcinol-type phenolic resin, and polyvinylphenol. , Lewis acid-amine complexes such as boron trifluoride-amine complex, boron pentafluoride-amine complex and arsenic pentafluoride-amine complex, dicyandiamide, 0-tolylbiguanide, phenylbiguanide and α-2,5
- dicyandiamide derivatives such as dimethyl biguanide, organic acid hydrazides such as succinic acid hydrazide, adipic acid hydrazide, isophthalic acid hydrazide and p-oxybenzoic acid hydrazide, diaminomaleonitrile derivatives such as diaminomaleonitrile and benzyldiaminomaleonitrile, melamine and Known epoxy curing accelerators such as melamine derivatives such as N,N-diallylmelamine, amine imide derivatives, and polymercaptans can be used.

These thermosetting catalysts may be used alone or in combination of two or more.

Examples of organic solvents include ketones such as methyl ethyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene and xylene, cellosolves such as cellosolve and butyl cellosolve, calpitols such as calpitol and butylcavitol, ethyl acetate, butyl acetate, and cellosolve acetate. ,
Examples include acetic acid esters such as butyl cellosolve acetate, carpitol acetate, and butyl carpitol acetate.

These organic solvents may be used alone or in combination of two or more.

Examples of thermal polymerization inhibitors include hydroquinone, p-
Methoxyphenol, pt-butylcatechol, 2,
Aromatic hydroxy compounds such as 6-di-t-butyl-p-cresol, β-naphthol and pyrogallol, quinones such as benzoquinone and p-)ruquinone, naphthylamine,
Examples include amines such as pyridine, p-toluidine, and phenothiazine, aluminum salts or ammonium salts of N-nitrosophenylhydroxylamine, floranil, and nitrobenzene.

Furthermore, the liquid photosensitive resin composition of the present invention includes a tackifier, an adhesion promoter, a dispersant, a plasticizer, an anti-sagging agent, a leveling agent, an antifoaming agent, a flame retardant, a brightening agent, a coloring agent, etc. Supplementary additives may be added as necessary.

Examples of tackifiers or adhesion promoters include alkylphenol/formaldehyde novolac resins, polyvinylethyl ether, polyvinyl isobutyl ether,
Polyvinyl butyral, polyisobutylene, styrene
Butadiene copolymer rubber, butyl rubber, vinyl chloride-vinyl acetate copolymer, chloride rubber, acrylic resin adhesive,
Examples include aromatic, aliphatic or alicyclic petroleum resins.

The addition of a tackifier or adhesion promoter increases the adhesion of the photosensitive resin to the substrate after photocuring, and this effect is particularly significant when used for silk printed wiring boards and solder printed wiring boards. .

A dispersant is used to improve the dispersibility, storage stability, etc. of a liquid photosensitive composition. The necessity of blending plasticizers, anti-sagging agents, leveling agents, and antifoaming agents depends on the method of using the liquid photosensitive resin composition, that is, the method of creating a coating film of the liquid photosensitive resin composition, and depends on the type used. and the amount is selected accordingly.

A single compound of these auxiliary additives may not only exhibit one type of property (dispersibility, plasticity, anti-sagging, leveling or antifoaming properties), but may also exhibit multiple additive effects. For example, dispersants may also act as plasticizers, leveling agents, and antifoaming agents in liquid photopolymer compositions, and dispersants, anti-sag agents, leveling agents, and antifoaming agents may also act as plasticizers, leveling agents, and antifoaming agents for photosensitive resin compositions after photocuring. It also has an effect on the glossiness of color resin compositions, and may act as a brightening agent.

As the dispersant, for example, a fluorine-containing polymer compound, a surfactant, a modified lecithin, a non-silicon long chain carboxylic acid amine salt, an organic montmorillite, etc. are used.

Examples of plasticizers include glycol esters such as ethylene glycol siphthalate, diethylene glycol siphthalate, ethylene glycol capriate, and diethylene glycol dicabrate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, diaryl phthalate, and butyl benzyl. Phthalic acid esters such as phthalate, phosphoric acid esters such as triphenyl phosphate and tricresyl phosphate, diethyl maleate, dibutyl adipate, triethyl citrate, and ethyl laurate are used.

As the anti-sag agent, inorganic fine powder such as talc, mica, silicon dioxide, titanium dioxide, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, magnesium sulfate, barium sulfate, etc. is used.

Examples of coloring agents include inorganic pigments such as titanium oxide, carbon black, and iron oxide, methylene blue, crystal violet, rhodamine B, tsuksin, auramine,
Organic dyes such as azo dyes and anthraquinone dyes, and phthalocyanine or azo organic pigments such as phthalocyanine blue and phthalocyanine green are used.

Examples of flame retardants include inorganic flame retardants such as antimony dioxide, zirconium hydroxide, barium metaborate, magnesium hydroxide, and aluminum hydroxide, tetrabromobisphenol A, chlorinated paraffin, and perchloropentacyclodecane. , tetrabromobenzene, halogenated flame retardants such as chlorinated diphenyl, and chlorinated phosphonitrile derivatives, vinyl phosphonate, allyl phosphonate, tris(β-chloroethyl) phosphonate, tricresyl phosphonate, phosphorus Phosphorous flame retardants such as ammonium chloride are used.

When forming an image using the liquid photosensitive resin composition of the present invention obtained in this manner, the liquid photosensitive resin composition is applied to a substrate, heated and cured to make the surface non-adhesive, and then A pattern mask is brought into close contact with the cured coating film, exposed to light, and developed with an alkaline aqueous solution to elute the uncured film to obtain an image.

Examples of methods for applying the liquid photosensitive resin composition of the present invention onto a substrate include a spray method, a dip method, a brush coating method, a roller coating method, a flow coater method, a curtain coating method, and a screen printing method. In particular, for coating printed wiring boards, thin metal films, etc., roller coating methods, curtain coating methods, screen printing methods, etc. are preferred.

In the liquid photosensitive resin composition of the present invention, it is preferable to heat-cure the coating film to eliminate the tackiness on the surface of the coating film before irradiating it with actinic rays.As a result of this heat-curing, it becomes non-tacky. This makes it possible to expose the cured coating film with the pattern mask in close contact with it.

Examples of the exposure light source used for photocuring the liquid photosensitive resin composition of the present invention include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, metal halide lamps, laser beams, etc. ~
It is preferable to use an exposure apparatus using a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, or a metal halide lamp as a light source that emits ultraviolet rays around 40 Onm.

The liquid photosensitive resin composition of the present invention can be developed with an alkaline aqueous solution. Examples of developing solutions include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, lithium carbonate\ammonia, and the like. A 1-10% by weight aqueous solution can be used, but in some cases amines such as primary amines such as butylamine, hexylamine, benzylamine, allylamine, secondary amines such as diethylamine, benzylethylamine, triethylamine, etc. Tertiary amines such as ethanolamine, jetanolamine, triethanolamine, hydroxylamines such as 2-amino-1,3-propanediol, cyclic amines such as morpholine, pyridine, piperazine, piperidine, hydrazine, ethylenediamine, hexamethylenediamine Polyamines such as amines, basic salts such as sulfates, carbonates, bicarbonates, alkali metal phosphates, and birophosphates of the above amines, quaternary ammonium salts such as tetramethylammonium hydroxide, choline, etc. are used. You can also.

Further, the liquid photosensitive resin composition of the present invention can be used after image formation.
Post-curing may be performed by heat treatment if necessary.

For the heat treatment in curing before exposure and post-curing after image formation, a heating device such as a hot air circulation drying oven or a far-infrared drying oven can be used.

Hereinafter, the present invention will be explained in more detail based on Examples, but the present invention is not limited by these Examples. Unless otherwise specified, "1 part" represents "part by weight".

(Synthesis Example-1) 50 parts of a cresol novolac type epoxy resin (Evicron N-673 manufactured by Dainippon Ink Co., Ltd.) with an epoxy equivalent of 210, 57.6 parts of an equimolar reaction product of glutaric anhydride/2-hydroxyethyl acrylate (epoxy group For, 1
．． 05 equivalent), benzyltriethylammonium chloride (0.54 part), and hydroquinone (0.075 part) were dissolved in 61.6 parts of carpitol acetate) and stirred at 80°C for 12 hours. The reaction rate of the epoxy group was determined by zero titration. 7
It was 0%.

To this reaction product, 35.5 parts of tetrahydrophthalic anhydride (0.98 equivalent to the epoxy group) was added, and the solution was further stirred at 80°C for 2.5 hours to form a solution of the photopolymerizable compound 1. Obtained.

The weight average molecular weight of this photopolymerizable compound was 3410 in terms of polystyrene. Furthermore, the M weight average molecular weight after aging at room temperature for 4 weeks was 4680 in terms of polystyrene.

(Synthesis Example-2) 57.5 parts of the glutaric anhydride/2-hydroxyethyl acrylate equimolar reaction product of Synthesis Example-1 was mixed with 54.0 parts of the succinic anhydride/2-hydroxyethyl acrylate equimolar reaction product (epoxy A solution of photopolymerizable compound 2 was obtained in the same manner as in Synthesis Example 1, except that 61.6 parts of carpitol acetate was changed to 60.0 parts based on the weight of 1.05 equivalents) and carpitol acetate).

The reaction rate of the epoxy group before addition of the acid anhydride was determined by titration to be 70%. The weight average molecular weight of this photopolymerizable compound was 10,660 in terms of polystyrene. Furthermore, when it was allowed to stand at room temperature for 4 weeks, it turned into a gel.

(Synthesis Example-3) 57.5 parts of the glutaric anhydride/2-hydroxyethyl acrylate equimolar reaction product of Synthesis Example 1 was placed on a tetrahydro anhydride lid*/67.1 parts of the 2-hydroxyethyl acrylate equimolar reaction product. (1.0 for epoxy groups
5 equivalents), 61.6 parts of carpitol acetate and 65.5 parts of carpitol acetate.
A solution of photopolymerizable compound 3 was obtained in the same manner as in Synthesis Example 1 except that the amount was 7 parts.

The reaction rate of the epoxy group before addition of the acid anhydride was determined by titration to be 71%. The weight average molecular weight of this photopolymerizable compound was 16,530 in terms of polystyrene. Further, the weight average molecular weight after aging at room temperature for 4 weeks was 35,260 in terms of polystyrene.

(Synthesis Example-4) 57.5 parts of the glutaric anhydride/2-hydroxyethyl acrylate equimolar reaction product of Synthesis Example-1 was added to 1 part of acrylic acid.
8.0 parts (1.05 equivalents relative to the epoxy group), 44.6 parts of carpitol acetate 61.6 parts, and a reaction time of 12 hours to 8 hours. A solution of polymerizable compound 4 was obtained.

The reaction rate of the epoxy group before addition of the acid anhydride was determined by titration to be 82%. The weight average molecular weight of this photopolymerizable compound was 4990 in terms of polystyrene. Further, the weight average molecular weight after aging at room temperature for 4 weeks was 5580 in terms of polystyrene.

(Examples and Comparative Examples) Example 1, Comparative Examples 1 to 3 Photopolymerizable compounds 1 to 4 shown in the synthesis examples were used to prepare a photosensitive liquid according to the following formulation using the photopolymerizable compounds 1 to 4 at one week and four weeks after synthesis. Ml-M4 and thermosetting liquid N were prepared.

<Photosensitive liquid M> 70% by weight carpitol acetate solution of photopolymerizable compound 350 parts Florene rAC-
300J 15 parts (Kyoeisha Yushi Kagaku Kogyo Co., Ltd.)
antifoaming agent) Phthalocyanine Green 2.5
Part Irgacure 907 27.5 parts (Photopolymerization initiator manufactured by Ciba Geigy) Silica 5 parts Barium sulfate 90 parts 1-benzyl-2-methylimidazole 10 parts + −−−−−+Photosensitive liquid Total 500 parts <Thermosetting liquid N> Triglycidyl 100 parts Isocyanurate dipentaerythritol 36 parts Hexaacrylate talc 14 parts Cellosolve acetate 50 parts + −−−−−−
−−−−−−−−−−−−−−+Thermosetting liquid N Total 200 parts The above photosensitive liquid M and thermosetting liquid N,
Each was kneaded separately using a roll mill to prepare an ink.

Next, the photosensitive liquid M and the thermosetting liquid N were kneaded to obtain a liquid photosensitive resin composition.

Table 1 shows the results of evaluating the performance of these liquid photosensitive resin compositions using the following method. Evaluations other than developability are based on the results when using a photopolymerizable compound one week after synthesis. It is.

l. Formation of coating film The copper-clad laminate was pretreated by polishing, washing, and removing moisture. A liquid photosensitive resin composition adjusted under various conditions was applied over the entire surface of the pretreated copper-clad laminate by screen printing, and dried at 70° C. for 30 minutes in a hot air circulation drying oven to obtain a coating film.

2. Evaluation of developability The coating film was developed under the following conditions, and the time for the coating film to dissolve was measured.

+Developer・・・1% sodium carbonate aqueous solution+Liquid temperature・
...25℃ 10 Spray pressure...1.8Kg/Cm23, evaluation of sensitivity A step wedge with a density step of 0.15 (Δ1 o gE) was brought into close contact with the coating film, and a 5KW ultra-high pressure mercury lamp was used at 10100O.
/cm2 and was developed for twice the time taken to dissolve the coating film to obtain a negative image corresponding to the wedge, and the number of stages (clear stage number) at which the image was completely dissolved was determined.

4. Evaluation of pencil hardness: After solid exposure with an exposure amount that gives a clear number of steps of 12, and after developing in the same manner as in 3, 5.
Post-cure for 0 minutes, JIS K 5400 B-1
Measured according to 4.

5. Evaluation of adhesion In the same way as the evaluation of pencil hardness, perform exposure, development, and post-curing.
A substrate test was conducted according to lrs K 5400 6-15.

6. Evaluation of insulation resistance Except for using a double-sided steel-clad laminate with an IPC-B-25 test pattern formed, exposure, development, and post-curing were performed in the same manner as the pencil hardness evaluation method, and in accordance with JISZ 3197. Using rTR-8601J manufactured by Atopan Test Co., Ltd., DC 500V was applied, and the resistance value was measured after 1 minute.

7. Evaluation of solvent resistance In the same way as the evaluation of insulation resistance, perform exposure, development, and post-curing.
The sample was dissolved in 1.1.1-trichloroethane at 20°C.
After immersion for a period of time, the condition and adhesion of the coating film were comprehensively evaluated.

8. Evaluation of acid resistance In the same way as for solvent resistance, exposure, development, and post-curing were performed, and the sample was immersed in a 10vol 1% sulfuric acid aqueous solution at 20°C for 30 minutes, and then the condition and adhesion of the coating film were evaluated. Judgment was made comprehensively.

(Effects of the Invention) As is clear from the above examples, the liquid photosensitive resin composition of the present invention has high sensitivity to ultraviolet light exposure, excellent developability with an alkaline aqueous solution, and changes in developability over time. It is a liquid photosensitive resin composition useful as a permanent protective mask for printed wiring boards, and has a coating film with excellent electrical properties, mechanical properties, and chemical resistance after curing.

Claims (1)

[Scope of Claims] 1) At least [1] (1) a novolak-type epoxy compound and (2) a dibasic acid hydroxy group forming a 4-membered ring or a 6-15-membered ring in the form of an acid anhydride. A liquid photosensitive resin composition comprising: a photopolymerizable compound obtained by sequentially reacting a (meth)acrylate half-ester and (3) a polybasic acid anhydride; [2] a photopolymerization initiator; thing. 2) At least, [1] (1) a novolac type epoxy compound and (2) a (meth)acrylate half ester having a hydroxy group of a dibasic acid forming a 4-membered ring or a 6- to 15-membered ring in the form of an acid anhydride. A liquid photosensitive resin composition comprising: a photopolymerizable compound obtained by sequentially reacting a compound, (meth)acrylic acid, and (3) a polybasic acid anhydride; [2] a photopolymerization initiator; thing.