JP2706858B2 - Photopolymerizable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkali-developable photopolymerizable composition which contains a novel binder and which is particularly excellent in that a peeled piece is fragmented. The photopolymerizable composition of the present invention is suitable for uses such as a dry film photoresist or photomask for producing a printed circuit board, a lithographic printing plate, and a resin relief printing plate.

[0002]

2. Description of the Related Art Conventionally, there are two methods for producing a printed circuit board, a tenting method and a plating method. In either method, unnecessary resist is removed in a circuit forming step. At this time, if the release piece is large, the release piece is entangled with the roll of the peeling machine, not only remarkably lowering the workability, but also the release piece may be reattached to a clean substrate, so the release piece is fine. Is preferred. Here, the size of the strip is greatly affected by the binder of the resist.

[0003] In recent years, dry film resists have been widely used in the field of making printed circuit boards. From the viewpoints of safety, impact on the environment, etc., dry film resists are preferably those which can be treated with an aqueous alkaline solution. It is widely known that a compound having a carboxyl group is used as a binder for a dry film resist.

As binders satisfying such requirements, Japanese Patent Application Laid-Open Nos. 64-55550 and 64-55551 are disclosed.
Methacrylic acid / methacrylic acid ester copolymers disclosed in the specification of JP-A No. 221960, a method using a mixture of methacrylic acid / styrene copolymers, and a method using a monofunctional monomer described in JP-A-2-221960. ing.

Although the use of these methods is effective in reducing the size of the peeled piece, the photosensitive layer is not removed from the edge of the film when the dry film is stored for a long time in a rolled state. This is not yet sufficient in that the exudation and fusion of adjacent films are likely to occur, that is, so-called edge fusion is likely to occur.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photopolymerizable composition which has a fine strip and is hard to cause edge fusion and which can be treated with an aqueous alkali solution.

[0007]

As a result of various studies, the present inventors have found a photopolymerizable composition which can achieve the above object. That is, an object of the present invention is to provide (1) a carboxyl group-containing binder, (2) a photopolymerizable monomer,
And (3) a photopolymerizable composition containing a photopolymerization initiator and developable with an alkaline aqueous solution, wherein
Of a monomer having the following general formula (b) and a monomer having the following general formula (c) having a weight-average molecular weight of 5,000 to 200,000 by 5% of the carboxyl group-containing binder. This has been achieved by a photopolymerizable composition characterized by including the above.

[0008]

Embedded image

(R1, R2, R3, and R5 are each a hydrogen atom or a methyl group; R4 is an alkyl group having 1 to 5 carbon atoms;
R6 represents a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a chlorine atom or a bromine atom;
An integer of 10 and a composition ratio of (a) 10 to 35% by weight;
(B) 1 to 30% by weight, (c) 35 to 85% by weight) Hereinafter, the present invention will be described in detail.

The monomer containing the general formula (a) which is a component of the copolymer according to the present invention is acrylic acid or methacrylic acid, and the monomer containing the general formula (b) is
Ethylene glycol monomethyl ether (meth) acrylate, diethylene glycol monomethyl ether (meth) acrylate, triethylene glycol monomethyl ether (meth) acrylate, tetraethylene glycol monomethyl ether (meth) acrylate, ethylene glycol monoethyl ether (Meth) acrylic
G, diethylene glycol monoethyl ether (meta)
Examples of monomers containing the general formula (c) such as acrylate, triethylene glycol monoethyl ether (meth) acrylate, and tetraethylene glycol monoethyl ether (meth) acrylate include styrenes. The molecular weight of the copolymer is 5,000-20.
000 is preferred.

Further, in the photopolymerizable composition of the present invention, in addition to the above-mentioned copolymer, a compound selected from the following wide variety of polymer substances may be used in combination as a binder. it can. Compounds that can be combined have good compatibility with photopolymerizable monomers and photopolymerization initiators, and manufacturing processes from preparation of coating solutions to coating and drying,
Do not cause demixing during storage of the obtained mixture and properties according to the use of the present invention, for example, when used for a photoresist for tenting, the molecular weight of the compound, intermolecular force, hardness, Considering the softening temperature, crystallinity, elongation at break, and the like, the strength, stretchability, abrasion resistance, chemical resistance, and the like of the binder can be appropriately selected from appropriate ones.

Specific examples of compounds that can be used as a binder include (meth) acrylic acid and alkyl (meth) acrylate (where the alkyl group is a methyl group,
Ethyl group, butyl group, etc.), poly (meth)
Copolymers of acrylic acid, styrene and unsaturated dibasic acid anhydrides such as maleic anhydride, reaction products of the polymers with alcohols, and reaction products of cellulose with polybasic acid anhydride, and the like.

Among the above-mentioned polymers, those particularly preferably used as the binder of the present invention are styrene / maleic anhydride copolymer, methyl methacrylate / methacrylic acid / methacrylic acid described in JP-A-60-258439. 2-ethylhexyl acid / benzyl methacrylate quaternary copolymer, styrene / maleic acid mono-n-butyl ester copolymer described in JP-B-55-38961, and styrene / copolymer described in JP-B-54-25957. Methyl methacrylate / ethyl acrylate / methacrylic acid quaternary copolymer, benzyl methacrylate / methacrylic acid copolymer described in JP-A-52-99810, JP-B-58
Tertiary copolymer of acrylonitrile / 2-ethylhexyl methacrylate / methacrylic acid described in JP-A-12577, and terpolymer of methyl methacrylate / ethyl acrylate / acrylic acid described in JP-B-55-6210 And styrene / maleic anhydride copolymer partially esterified with isopropanol.

These polymers may be used alone as a binder, but have good compatibility and do not cause demixing during the production process from preparation of the coating solution to coating and drying, and storage of the resulting mixture. Two or more polymers may be mixed in an appropriate ratio and used as a binder.

The molecular weight of the polymer used as the binder can vary widely depending on the kind of the polymer, but is 5,000 to 2,000,000, preferably 1 to 2,000,000.
000 to 200,000, more preferably 40,
Those having a range of 000 to 85,000 are suitably used in the present invention. When the molecular weight is less than 5,000, the mechanical strength of the photopolymerized resist becomes insufficient, and
If it exceeds 000, the developability deteriorates and is not suitable for the purpose of the present invention.

The total amount of the binder containing the copolymer of the present invention is preferably 4 to the solid content of the photopolymerizable composition.
It is 0 to 90% by weight, more preferably 50 to 70% by weight. If the content is less than 40% by weight, the flowability of the photopolymerizable composition is too high, so that edge fusion is likely to occur.
If the content is more than 10% by weight, the difference in solubility between the exposed portion and the unexposed portion becomes too small to obtain good image quality, and neither is suitable for the purpose of the present invention.

The photopolymerizable monomer that can be used in the present invention includes, for example, JP-A-60-25853.
No. 9, (Japanese Patent Application No. 1-91247), and (meth) acrylic acid esters. Specifically, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, nonaethylene glycol di (meth) acrylate, tetradecaethylene glycol di (meth) acrylate, nona Propylene glycol di (meth) acrylate, dodecapropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide adduct tri (meth) acrylate, pentaerythritol di (meth) acrylate, penta Erythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerol Di (meth) acrylate, (meth) acrylic acid esters of 1,3-propanediol di (meth) polyols such acrylate.

Examples of (meth) acrylamides include methylenebis (meth) acrylamide, ethylenediamine, diaminopropane, diaminobutane, pentamethylenediamine, bis (2-aminopropyl) amine, diethylenetriaminediamine, phenylenediamine, diaminobenzoic acid and the like. There are poly (meth) acrylamides derived from

Examples of the allyl compound include diallyl esters such as phthalic acid and malonic acid, and diallyl esters such as benzenedisulfonic acid and 2,5-dihydroxydisulfonic acid.

As the vinyl ether compound, for example,
Examples include ethylene glycol divinyl ether and 1,3,5-tri-β-vinyloxyethoxybenzene.

Examples of vinyl esters include divinyl succinate and divinyl adipate.

Examples of the styrene compound include divinylbenzene and p-allylstyrene.

Further, a reaction product obtained by reacting a polyol compound having at least two hydroxyl groups with a slightly excess polyisocyanate compound having at least two isocyanate groups has at least one hydroxyl group and at least one ethylene compound. A polyfunctional urethane compound having at least two ethylenically unsaturated groups, which is obtained by reacting with a compound having an ethylenically unsaturated group, can also be suitably used in the present invention.

The amount of the photopolymerizable monomer is in the range of 10 to 60% by weight, preferably 25 to 50% by weight of the solid content of the photopolymerizable composition. If the amount is less than 10% by weight, the difference in solubility between the exposed and unexposed parts is too small, so that good image quality cannot be obtained. If the amount exceeds 60% by weight, the flowability of the photopolymerizable composition is too high. It is not suitable for the purpose of the present invention because it tends to cause edge fusion.

Suitable photopolymerization initiators that can be used in the present invention include about 300-800 nm, more preferably 330 nm.
It preferably contains at least one component having a molecular extinction coefficient of at least about 50 in the range of -500 nm. Examples thereof include aromatic ketones, lophine dimers, benzoin and benzoin ethers, polyhalogens, and photopolymerization initiator systems combining two or more of these. The following compounds can be given as specific examples of these.

As aromatic ketones, benzophenone, 4,4'-bis (dimethylamino) benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4,4'-dimethoxybenzophenone, 4-dimethylaminobenzophenone, -Dimethylaminoacetophenone, benzyl, anthraquinone, 2-tert-butylanthraquinone, 2-methylanthraquinone, xanthone, thioxanthone, 2-chlorothioxanthone,
Examples include 2,4-diethylthioxanthone, fluorenone, and acridone.

Examples of the preferably used dimers of roffin include the above-mentioned JP-B-45-37377, JP-B-48-38403, JP-A-56-35134 and JP-A-63-200605. And the like. That is, 2- (o-chlorophenyl)
-4,5-diphenylimidazole dimer, 2- (o-
(Chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2-
(O-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5
-Diphenylimidazole dimer and the like.

Examples of benzoin and benzoin ethers include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin phenyl ether.

Examples of the polyhalogen compound include carbon tetrabromide, phenyltribromomethylphenylsulfone, phenyltrichloromethylketone, and JP-A-53-1.
33428, JP-B-57-1819, JP-B-57-
No. 6096 and U.S. Pat. No. 3,615,455. Particularly preferred examples are 4,
4'-bis (dimethylamino) benzophenone, 4,
4'-bis (diethylamino) benzophenone, 2,4
-Diethylthioxanthone, a combination of 4,4'-bis (diethylamino) benzophenone and benzophenone,
A combination of 4,4'-bis (diethylamino) benzophenone and phenyltribromomethylphenylsulfone is exemplified.

The content of the photopolymerization initiator (system) is preferably 0.1 to 20% by weight, more preferably 0.2 to 10% by weight, based on the solid content of the photopolymerizable composition. 0.1
If the amount is less than 20% by weight, the sensitivity is insufficient, and if the amount exceeds 20% by weight, the physical properties of the film of the photopolymerizable composition are adversely affected.

As described above, the photopolymerizable composition of the present invention contains a carboxyl group-containing binder, a photopolymerization initiator (system), and a photopolymerizable monomer as main components. A polymerization inhibitor, a plasticizer, a dye, a color-change agent, an adhesion promoter, and the like may be used in combination, so that a desired photoresist, resin relief plate, planographic printing plate, photomask, and the like can be prepared in a wide range.

The thermal polymerization inhibitor is added to prevent thermal polymerization of the photopolymerizable composition or polymerization with time.
Thereby, the chemical stability at the time of preparation of the photopolymerizable composition or at the time of storage until it is used after being laminated on a metal plate can be enhanced. Examples of the thermal polymerization inhibitor include p-methoxyphenol, hydroquinone, benzoquinone, o-toluquinone, p-toluquinone, t-butylcatechol, pyrogallol, 2-hydroxybenzophenone, and 4-methoxy2.
-Hydroxybenzophenone, cuprous chloride, phenothiazine, floranil, chloranil, naphthylamine, pyridine, p-toluidine, β-naphthol, 2,6-di-
Examples include t-butyl-p-cresol, nitrobenzene, dinitrobenzene, picric acid, aluminum salts or ammonium salts of N-nitrosophenylhydroxylamion, methylene blue organic copper, methyl salicylate, aryl phosphite, and the like. The preferable addition amount of the thermal polymerization inhibitor is 0.1 to the solid content of the photopolymerizable composition.
001 to 10% by weight, more preferably 0.01 to 3% by weight. If it is less than 0.001% by weight, the thermal stability is poor, and if it exceeds 10% by weight, the sensitivity decreases.

The plasticizer is added to adjust the film quality of the photopolymerizable composition before and after photocuring, other physical properties, photosensitivity and the like. Examples of the plasticizer include phthalic esters such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, and diallyl phthalate; glycol esters such as triethylene glycol diacetate and tetraethylene glycol diacetate; and p-toluene sulfone Acid amides such as amide, benzenesulfonamide and Nn-butylbenzenesulfonamide; aliphatic dibasic acid esters such as diisobutyl adipate, dioctyl azelate and dibutyl maleate; tributyl citrate; glycerin triacetate; lauric acid Butyl 4,5-diepoxycyclohexane-1,2-dicarboxylate dioctyl and the like. The preferable addition amount of the plasticizer is 0.001 to 50% by weight, more preferably 0.01 to 20% by weight of the solid content of the photopolymerizable composition. If it exceeds 50% by weight, the developability and the image quality are adversely affected.

Dyes are added for coloring the photopolymerizable composition. Examples of dyes include malachite green, methyl green, brillat green, methyl violet, crystal violet, ethyl violet, Victoria Pure Blue BOH, and oil blue # 603.
(Manufactured by Orient Chemical Co., Ltd.), eosin, erythrosin B, rose bengal, rhodamine B, rhodamine 6G, 2,7-dichlorofluorescein, phenolphthalein, alizarin red S, thymolphthalein,
Quinaldine red, methanil yellow, thymol sulfophthalein, diphenyltriazene, xylenol blue, methyl congo red, diphenylthiocarbazone,
Examples include paramethyl red, congo red, benzobulbulin 4B, α-naphthyl red, nile blue A, phenacetaline, parafuchsin, and basic fuchsin. The preferable addition amount of the dye is 0.001 to 10% by weight, more preferably 0.1 to 5% by weight of the solid content of the photopolymerizable composition. If it exceeds 10% by weight, the sensitivity is adversely affected.

The color change agent is added so that a visible image can be obtained when the photopolymerizable composition is irradiated with light through a photomask. Examples of the color changing agent include diphenylamine, dibenzylaniline, triphenylamine, diethylaniline, diphenyl-p-phenylenediamine, p-toluidine, 4,4′-biphenyldiamine, o-chloroaniline, p, p ', p "-hexamethyltriaminotriphenylmethane, p, p'-tetramethyldiaminotriphenylmethane, p, p', p" -triaminotriphenylcarbinol and the like. The preferred amount of the color changing agent is 0.001 to 10% by weight of the solid content of the photopolymerizable composition, more preferably 0.01 to 5%.
% By weight. If the content exceeds 10% by weight, sensitivity lowering and fogging are likely to occur.

The adhesion promoter is added to enhance the adhesion of the photopolymerizable composition to the surface of a metal plate such as copper, stainless steel, anodized aluminum, and silicon. Examples of the adhesion promoter include benzimidazole and benzthiazole described in JP-B-50-9177.
Benztriazole, 2-mercaptobenzthiazole, 2-mercaptobenzimidazole described in JP-A-53-702, JP-A-59-11343
No. 2, JP-A-59-16501, JP-A-60-125
No. 43, JP-A-60-12544, JP-A-61-17
Compounds described in each specification of No. 2139 can be exemplified. A preferable addition amount of the adhesion promoter is 0.001 to 10, more preferably 0.01 to 5% by weight of the solid content of the photopolymerizable composition. If it exceeds 10% by weight, it may cause development residue.

The photopolymerizable composition of the present invention forms a resist image by dissolving and removing (developing) the unexposed portion after laminating and image-exposing the substrate. The photopolymerizable composition of the present invention can be developed with an alkaline aqueous solution. As the developer, for example, an aqueous solution of 0.1 to 10% by weight of sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, lithium carbonate, ammonia or the like can be used. , Amines such as butylamine, hexylamine,
Primary amines such as benzylamine and allylamine, secondary amines such as diethylamine and benzylethylamine, tertiary amines such as triethylamine, ethanolamine, diethanolamine, triethanolamine and 2-amino-
Hydroxylamines such as 1,3-propanediol, cyclic amines such as morpholine, pyridine, piperazine and piperidine, and basic salts such as sulfates, carbonates, bicarbonates, alkali metal phosphates and pyrophosphates of the amines And hydroxy salts such as tetramethylammonium hydroxide and choline. Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. Here, “parts” means “parts by weight” unless otherwise specified.

[0038]

【Example】

 Examples 1 and 2, Comparative Examples 1 to 5 The following materials were mixed to prepare a uniform solution. Dodecapropylene glycol diacrylate 15.0 parts Tetraethylene glycol dimethacrylate 3.5 parts p-toluenesulfonamide 1.2 parts 4,4'-bis (diethylamino) benzophenone 0.12 parts Benzophenone 2.3 parts 2- (2 '-Chlorophenyl) -4,5-diphenylimidazole dimer (25% by weight dichloromethane solution) 4.5 parts Tribromomethylphenylsulfone 0.25 parts Leuco crystal violet 0.25 parts Malachite green 0.02 parts

To the thus obtained solution (27.14 parts), 35% methyl ethyl ketone solutions of various binders in the amounts shown in Table 1 were added. After further stirring and dissolving,
Each solution was applied on a polyethylene terephthalate temporary support having a thickness of 20 μm, dried at 100 ° C. for 2 minutes, and dried for about 4 hours.
Two photosensitive materials having a photosensitive resin coating film having a thickness of 0 μm were produced. These light-sensitive materials were evaluated by the following methods.

1. Evaluation of peeled piece One of the photosensitive materials prepared above was laminated at 105 ° C. on a cleaned copper-clad laminate (copper thickness 35 μm). Fifteen minutes later, 70 m was passed through a negative manuscript for etching using a 5 kW ultra-high pressure mercury lamp (HMW-532D manufactured by Oak Co., Ltd.).
j / cm ² exposure. After 15 minutes of exposure, after spray-developing with a 1% aqueous solution of sodium carbonate (30 ° C.) for 40 seconds,
Washed with water at 20 ° C. for 40 seconds. The resist pattern thus obtained was stripped with a 3% NaOH aqueous solution at 50 ° C., and the size of the strip was evaluated.

2. Evaluation of edge fusion The remaining other photosensitive material was cut into 5 cm squares exactly and 10
The sheets were stacked and a 1 kg weight was placed thereon. The samples were stored in an atmosphere of 30 ° C. and 80%, and after one week, it was checked whether the ends of the ten samples were fused. Table 1 shows the evaluation results.

[0042]

[Table 1]

It can be seen from the above that when the photopolymerizable composition of the present invention is used, the size of the peeled piece is small and the edge fusion is hardly generated.

[0044]

The resist using the photopolymerizable composition of the present invention as a binder has a small release piece size and is less likely to cause edge fusion.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location G03F 7/028 G03F 7/028 H01L 21/027 H05K 3/06 H H05K 3/06 H01L 21/30 502R

Claims (3)

(57) [Claims] (1) a carboxyl group-containing binder,
In a photopolymerizable composition containing (2) a photopolymerizable monomer and (3) a photopolymerization initiator and developable with an alkaline aqueous solution, a monomer containing the following general formula (a); And a weight average molecular weight of the monomer containing the following general formula (c): 5,000 to 200,0
A photopolymerizable composition comprising the copolymer of No. 00 in an amount of 5% or more of the carboxyl group-containing binder. Embedded image (R1, R2, R3 and R5 are each a hydrogen atom or a methyl group, R4 is an alkyl group having 1 to 5 carbon atoms, R6 is a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a chlorine atom or a bromine atom. N represents an integer of 1 to 10, and the composition ratio is (a) 10 to 35% by weight, (b) 1 to 3
0% by weight, (c) 35 to 85% by weight) 2. The method according to claim 1, wherein the carboxyl group-containing binder other than the carboxyl group-containing copolymer is methacrylic acid, methyl methacrylate, benzyl methacrylate, or 2-ethylhexyl acrylate copolymer. Characteristic photopolymerizable composition. 3. The photopolymerizable composition according to claim 1, wherein the photopolymerization initiator contains a lophine dimer.