KR900003848B1 - Manufacture of printed wiring board - Google Patents

Abstract

1. coating the surface of a substrate (on the pts. where Cu is to be deposited by non electrolytic plating) with a photosensitive resin compsn., which contains (A) 100 (wt.) pts. photopolymerisable mixt. of (A1) 5-00%unsate. cpd (s). contg. terminal methacryloyl gp (s). and (A2) 95-1% unsatd. cpd (s). with terminal acryloyl gp (s)., (B) 0-400 pts. linear high mol. cpd. and (C) 0.5-20 pts. sensitiser or and sensitiser system, which can form a free radical on exposure to actinic radiation, in which (A1), (A2) and (B) have no N attached directly to H atom (s) in the mol.; 2. selective exposure of the coating to actinic radiation and developement to form a negative pattern; and 3. non electrolytic Cu plating, using the resin as plating resist.

Description

Manufacturing Method of Printed Circuit Board

1 is a schematic diagram of an apparatus for producing a photosensitive element used in an embodiment of the present invention.

2 is a schematic diagram of a test negative mask used in an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

5: feed roll of polyethylene terephthalate film

6, 7, 8: roll 9: knife

10 photosensitive resin composition solution 11 dryer

12: feed roll of polyethylene film 13, 14: roll

15 winding roll of photosensitive element 16 polyethylene derephthalate film

17 polyethylene film 21 opaque portion of the negative mask

22: transparent part of negative mask

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a printed circuit board, and more particularly, to a method of manufacturing a printed circuit board in which a circuit pattern is formed on a substrate by electroless plating using a photoresist.

Most printed circuit boards are manufactured by etching copper clad laminated substrates to remove copper in portions other than the printed circuits later (this method is called an etched foil process). On the other hand, a method of forming an integrated circuit pattern by electroless copper plating of a lead-free laminated substrate without using a copper clad laminated substrate (this method is called an additive process) does not have the disadvantage of eliminating unnecessary eastern powder. It is attracting attention recently because the unit price is low. However, in the additive method, the copper deposition rate is very low in electroless copper plating, so that the insulating laminated substrate is used for a long time (usually 5 to 60 hours) in a high alkali (usually pH 11 to 13.5) plating bath at high temperature (usually 60 ° C to 80 ° C). Should be soaked. Therefore, there is a need for an electroless plating resist that can withstand the above stringent conditions.

The resist is formed by screen printing an ink mainly composed of an epoxy resin and a curing agent on a substrate, and thermosetting the printed ink. However, since the dimensional accuracy of a printed line is limited, manufacture of a printed circuit board which has a high density pattern is difficult by the additive method. A photoresist is suitable for forming a high density pattern, and the photoresist used in the additive method is, for example, Japanese Patent Application Laid-Open Nos. 43468/1975, 770/1979, 199341/1983, and 12434 /. 1984, 56344/1986, and 101532 / l985. However, the photoresist proposed or commercially available so far, when the mass production of the printed circuit board using this photoresist in the photo-additive method, part of the photoresist composition is gradually dissolved in the electroless plating solution and gradually plated. Contamination of the solution has the disadvantage of attenuating the copper properties precipitated by electroless contraction. Such a reduction in the properties of copper is detrimental to the reliability of the formed printed circuit board, so that the plating solution used once is difficult to mass-produce and cannot be reused.

An object of the present invention is to provide a manufacturing method of a high precision printed circuit board having good copper plating characteristics as a photoadditive method. Another object of the present invention is to provide a mass production method of the printed circuit board.

The present invention relates to a method for manufacturing a printed circuit board, which comprises (A) (a) at least one terminal methacryloyl group on the surface of the substrate (necessary portion where copper should be deposited by electroless plating). 5 to 9% by weight of at least one type of unsaturated compound having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule and (b) having at least one terminal acryloyl group directly at least one hydrogen atom in the molecule 100 parts by weight of a photopolymerizable mixed component constituting 95 to 1% by weight of at least one type of unsaturated compound having no nitrogen atom bonded thereto, and (B) a linear polymer compound having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule A photosensitive resin bath containing 0 to 400 parts by weight and (c) 0.5 to 20 parts by weight of a sensitizer and / or a sensitizer, which generates free radicals upon irradiation of actinic light. Forming a water layer, (2) irradiating and developing normal actinic light onto the photosensitive resin composition to form a negative pattern of the photosensitive resin composition on the surface of the substrate, and (3) plating resist As an electroless copper plating on the substrate using the negative pattern of the photosensitive resin composition to form a circuit pattern on the surface of the substrate.

Hereinafter, a method of manufacturing a printed circuit board according to the present invention will be described in detail.

The manufacturing method of the printed circuit board which concerns on this invention comprises the step of forming the photosensitive resin composition layer in the necessary part which copper should deposit by electroless plating on the surface of a board | substrate.

As a substrate, a laminate such as a paper-phenol resin laminate and a glass-epoxy resin laminate and an iron-magnetic enamel substrate, a metal sheet (for example, an aluminum sheet) and a substrate composed of an epoxy resin insulating layer formed on both surfaces of the sheet. Metal core-containing substrates can be used. The plating catalyst can be attached to the inner wall of the perforations formed by drilling holes in these substrates and immersing them in a solvent containing the plating catalyst. As the plating catalyst solution, for example, HS-101B available from Hitachi Chemical Co., Ltd. can be used.

For example, it is preferable to form an adhesive layer on the surface of the substrate in order to facilitate adhesion of the copper to be subsequently deposited by the plating catalyst or electroless plating.

As the adhesive, a phenol-modified nitrile rubber adhesive known as the adhesive in the additive method can be used. The adhesive can include a compound that acts as a plating catalyst. For easier adhesion, the plating catalyst or the copper to be subsequently precipitated by electroless plating, it is preferable to roughen the surface of the adhesive layer before the surface is subjected to electroless plating. The said surface roughening can be performed by immersing the board | substrate with an adhesive layer in the acid solution containing sodium bichromate, chromic acid, etc., for example. As is well known, the surface roughening step may be before the formation of the photosensitive resin composition layer described below or after the formation of the resist pattern, as long as this step is before the electroless copper plating step.

As the substrate, for example, a laminate (eg, paper-phenol resin laminate, glass-epoxy resin laminate) or a metal core-containing substrate (eg, iron-magnetic enamel substrate, metal sheet (eg, aluminum sheet) ) And a copper clad substrate manufactured by attaching copper foil to both surfaces of the substrate composed of an epoxy resin insulating layer formed on both surfaces of the metal sheet. These substrates can be drilled and immersed in a solution containing the plating catalyst to cause the plating catalyst to adhere to the inner wall of the formed pores. Further, in order to improve the adhesion between copper and the plating resist to be formed later, the surface of the adhered copper foil may be etched with a water-soluble acidic aqueous solution containing an oxidizing agent such as cupric chloride. When using a copper-clad substrate, a negative pattern of the photosensitive resin composition is formed as a plating resist on the copper foil of the substrate, and a circuit pattern is formed on portions of the substrate other than the negative pattern by electroless copper plating, and the plating resist is removed. And copper foil between lines of a circuit pattern is removed by etching, and a printed circuit board is obtained. Alternatively, the copper foil of the substrate is etched to form a circuit pattern, and then a negative pattern of the photosensitive resin composition is formed on the substrate portions other than the perforations and land portions, and the perforations and land portions without the negative patterns are electroless copper plated. By forming the final circuit pattern, a printed circuit board can be obtained.

The photosensitive resin composition used in the present invention is, as an essential component, (a) at least one unsaturated compound having at least one terminal methacryloyl group and having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule thereof. To 99% by weight and (b) at least one terminal acryloyl group and a photopolymerizable mixed component constituting 95 to 1% by weight of at least one type of unsaturated compound having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule thereof. Configure As at least one type of unsaturated compound (a) having at least one terminal methacryloyl group and not having a nitrogen atom directly bonded to at least one hydrogen atom in the molecule thereof, for example, trimethylolpropane, trimethylolethane, pentaeryte Methacrylic acid esters of polyalcohols such as lititol, dipentaerythritol, 1,6-hexanediol, propylene glycol, tetraethylene glycol, dibromoneopentyl glycol, dicyclopentenyloxyethyl methacrylate, tetrahydrofur Furyl methacrylate, benzyl methacrylate, etc. are mentioned.

As at least one unsaturated compound (b) having at least one terminal acryloyl group and not having a nitrogen atom directly bonded to at least one hydrogen atom in the molecule thereof, for example, trimethylolpropane, trimethylolethane, pentaerythritol Acrylic esters of polyglycols such as rolls, dipentaerythritol, 1,6-hexanediol, propylene glycol, tetraethylene glycol, dibromoneopentyl glycol, dicyclopentenyloxyethyl acrylate, tetrahydrofurfuryl acrylic Elate, benzyl acrylate, etc. are mentioned.

As a result of in-depth research in the present invention, the presence of at least one essential atom in the unsaturated compounds (a) and (b) reduces the chemical and physical properties of the precipitated copper in many cases, in particular at least one directly bonded to at least one hydrogen atom. The presence of groups containing nitrogen atoms such as primary or secondary amido groups, amido groups and urethane groups has been shown to significantly reduce the chemical and physical properties of the deposited copper. In addition, the presence of a group containing at least one oxygen atom directly bonded to a hydrogen atom, for example, a hydroxyl group, a carboxyl group or the like is not preferable. In particular, preferred examples of the unsaturated compound (a) are trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol hexamethacrylate, and 1,6-hexanediol diol. Methacrylate. In addition, although the reason is not clear, contamination of the plating bath is reduced by using a mixture with a methacrylate-type unsaturated compound or only a methacrylate-type unsaturated compound as compared with using only an acrylate-type unsaturated compound as a photopolymerizable component. It has been shown that the properties of copper have been significantly improved.

The amount of unsaturated compound (a) and unsaturated compound (b) in the photopolymerizable component is 5 to 99% by weight and 95 to 1% by weight, respectively, in view of the photosensitivity of the photosensitive resin composition and the chemical and physical properties of copper deposited by electroless plating. Is determined. The amount of the compound (a) is preferably 20 to 95% by weight, and the amount of the compound (b) is preferably 80 to 5% by weight.

The photosensitive resin composition used in the present invention comprises 0 to 400 parts by weight of a linear polymer compound having no nitrogen atom directly bonded to at least one hydrogen in a molecule relative to 100 parts by weight of the unsaturated compounds (a) and (b). When the amount of the linear polymer compound exceeds 400 parts by weight, the photosensitive resin composition is low in photosensitivity and has no practical applicability. Linear high molecular compounds without nitrogen atoms directly bonded to at least one hydrogen atom include, for example, methyl methacrylate, ethyl acrylate, tetrahydrofurfuryl methacrylate, methacrylic acid, 2-hydroxyethyl methacrylate, Vinyl polymer compounds obtained by polymerizing or copolymerizing vinyl monomers such as benzyl methacrylate, styrene, vinyltoluene, vinyl acetate, butadiene and the like, as well as dihydric alcohols (for example, ethylene glycol, dipropylene glycol, 1 A polyester type high molecular compound obtained by condensing a 6-hexanediol etc.) and a dicarboxylic acid (for example, maleic acid, phthalic acid) is mentioned. It is preferable to use a linear polymer compound having at least one tetrahydrofurfuryl group as the side chain because it improves the deposited copper properties.

As will be described later, when the photosensitive resin is attached to form a photosensitive resin composition layer on a substrate, the amount of the linear high molecular compound having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule is photopolymerizable in view of film formability. 20-400 weight part is preferable with respect to 100 weight part of component (A).

The photosensitive resin composition used in the present invention comprises 0.5 to 20 parts by weight of a sensitizer and / or a sensitizer based on 100 parts by weight of the photopolymerizable component (A) that can generate free radicals upon irradiation with actinic light. When the quantity of a sensitizer and / or a sensitizer system is less than 0.5 weight part, the photosensitive resin composition is low in photosensitivity. When this amount exceeds 20 weight part, the shape of the formed negative pattern is bad.

As a sensitizer, for example, substituted or unsubstituted such as 2-ethylanthraquinone, 2-t-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone and the like Multinuclear quinones: ketoaldonyl compounds such as diacetyl, benzyl, etc .: alpha-ketoaldonyl alcohols such as benzoin, pivalon, etc .: ethers: alpha, such as alpha-phenylbenzoin, alpha, alpha-diethoxyacetophenone, etc. -Hydrocarbon-substituted aromatic acyls: and aromatic ketones such as benzophenone, 4, 4'-disdialkylaminobenzophenone and the like can be used. These compounds may be used alone or in combination. As the sensitizer, for example, (a) a dimer of 2,4,5-triarylimidazole and (b) 2-mercaptobenzoquinazole, leucocrystal violet, or tris (4-diethylamino-2- Combinations of methylphenyl) methane can be used. In addition, one of the sensitizers may be added to the material itself is not photoinitiation, but can enhance the photoinitiation of the sensitizer. For example, tertiary amines such as triethanolamine and the like can be added to benzophenone to improve the photoinitiation of benzophenone.

The photosensitive resin composition used for this invention can further comprise another secondary component. Secondary components include thermal polymerization inhibitors, dyes, pigments, paint improvers and the like. The selection of these secondary components is made under the same considerations as in conventional photosensitive resin compositions.

The manufacturing method of the printed circuit board which concerns on this invention necessarily comprises forming the above-mentioned photosensitive resin composition layer in the necessary part which copper should deposit by electroless plating on the surface of a board | substrate. This step can be carried out according to a conventional method. For example, the photosensitive resin composition of the present invention is uniformly dissolved or dispersed in a solvent such as methyl ethyl ketone, toluene, methylene chloride, and the solution is subjected to electroless plating by a dip coating method, a few coating method, or the like. By coating on the surface of the insulating substrate to be deposited, drying the applied substrate and removing the solvent. Alternatively, the solution of the photosensitive resin composition is not applied directly onto the substrate, that is, the solution is applied onto the base film according to a known method such as knife coating, roll coating, or the like, and the applied film is applied. Dry to prepare a photosensitive element composed of a base film and a photosensitive resin composition layer formed thereon, and then heat and press the photosensitive element on the surface of the insulating substrate on which copper should be deposited by electroless plating according to a known method. As the base film, a known film such as a polyester film, a polypropylene film, a polyimide film, a polystyrene film, etc. may be used, etc. Use of the photosensitive element in the formation of the photosensitive resin composition layer This preferable one is provided with a uniform photosensitive resin composition layer and furthermore a low solvent resistance Because it can be used.

In the method of manufacturing a printed circuit board according to the present invention, the photosensitive resin composition layer may be formed by irradiating phase active light to develop a portion of the photosensitive resin composition in a necessary part where copper should be deposited by electroless plating on the surface of the substrate. A step of forming a negative pattern is necessarily constituted. Irradiation of the actinic light may be performed by applying light emitted from a light source such as an ultrahigh pressure mercury lamp or a high pressure mercury lamp through a negative mask. Alternatively, the laser beam or the like may be scanned by a small cross-sectional image. For example, the development may be performed by immersing a substrate having a photosensitive resin composition layer irradiated with actinic light onto a developer such as 1,1,1-trichloroethane, or spraying the developer onto a substrate. have.

It is preferable to re-irradiate the substrate with actinic light after development because the photocuring of the photosensitive resin composition can be made more complete, the plating resistance can be improved, and the contamination of the plating bath can be reduced. Re-irradiation of actinic light can be performed to the whole surface of a board | substrate using light sources, such as an ultrahigh pressure mercury lamp and a high pressure mercury lamp.

The manufacturing method of the printed circuit board which concerns on this invention necessarily comprises forming the circuit pattern on the surface of a board | substrate by electroless copper plating a board | substrate using the negative pattern of the photosensitive resin composition as a plating resist. As said electroless plating liquid, the plating liquid containing copper salt, a complexing agent, a reducing agent, and a pH adjuster can be used.

As copper salt, copper sulfate, copper acetate, copper formic acid, and cupric chloride can be used, for example. Examples of the complexing agent include ethylenediaminetetraacetic acid, N-hydroxyethylethylenediaminetriacetic acid, N, N, N ', N'-tetrakis-2-hydroxypropylethylenediamine, and Rochelle salt. It is available. As a reducing agent, formalin is preferable. As the pH adjuster, alkali hydroxides such as sodium hydroxide, potassium hydroxide and the like are usually used. In some cases, various other additives may be added to the plating liquid to enhance its stability or to improve the precipitated synonym. From the standpoints of the stability of the plating liquid and the deposited copper properties, the plating liquid preferably has a copper concentration of 1 to 15 g / 1, pH 10 to 13.5, and a temperature of 50 ° C to 90 ° C. In the electroless plating, the catalyst is attached and / or solvated as necessary.

After forming the circuit pattern by electroless plating, the negative pattern of the photosensitive resin composition used as the plating resist may be peeled off or removed, or left as a permanent resist.

After the formation of the circuit pattern, the entire surface or the required surface portion of the circuit pattern is coated with solder such as a solder leveler or gold plated or tin plated to prevent oxidation of the copper surface, and the contact resistance when the portion becomes an electrical connection portion. Can be lowered. After coating the copper surface with solder, gold, tin, or the like, a solder mask may be formed on the required portion of the substrate as it is. The soul mask can also be used as a resist that covers only a necessary portion of the circuit pattern with solder or the like. The soul mask may be formed by printing and curing an epoxy resin ink according to a screen printing method, or may form a high precision soul mask mask by a photo method. The manufactured printed circuit board can be applied to various fields according to a known method. For example, it can attach and use an electronic component by soldering it. Moreover, the printed circuit board after electroless plating can also be used as the board | substrate of the intermediate | middle layer of a multilayer printed circuit board.

The present invention will be described in detail with reference to the following examples. However, the present invention is not limited to these examples. In Examples and Comparative Examples, parts refer to parts by weight.

Example 1

Trimethylolpropane trimethacrylate 46 parts

Trimethylolpropane triaclinite part 4

Methyl methacrylate-tetrahydrofurfuryl

50 parts of methacrylate (80/20 weight ratio) copolymer

Benzophenone part 3

0.1 part of 4,4'-bis (diethylamino) benzophenone

Victoria Pure Blue 0.01

100 parts methyl ethyl ketone

The photosensitive resin composition solution 10 of the said formulation was apply | coated uniformly to the 25-micrometer-thick polyethylene terephthalate film 16 using the apparatus of FIG. The applied film was dried at 80 ° C. to 100 ° C. for about 10 minutes with a hot air convection dryer 11. After drying, the thickness of the photosensitive resin composition layer was about 35 micrometers. As shown in FIG. 1 as a cover film, the polyethylene film 17 of thickness about 25 micrometers was affixed on the said photosensitive resin composition layer, and the photosensitive element was obtained.

In Fig. 1, reference numeral 5 denotes a polyethylene terephthalate film supply roll, reference numerals 6, 7, and 8 denotes a knife 9, a reference numeral 12 denotes a polyethylene film supply roll, reference numerals 13 and 14 a roll, and Reference numeral 15 is a photosensitive element winding roll.

On the other hand, an adhesive (No. 777, manufactured by ACI Japan KK) mainly composed of acrylonitrile-butadiene rubber-modified phenolic resin was applied to the positive surface of a paper phenol laminate (LP-461F, manufactured by Hitachi Chemical Co., Ltd.) having a thickness of 1. It was. The laminated board | substrate with an adhesive bond layer of thickness 30micrometer was obtained by heating the apply | coated board | substrate at 160 degreeC for 110 minutes, and hardening an adhesive agent. Then, a hole was drilled in the required position of the plate by using a drill, and then the plate was immersed in a surface roughening solution containing chromic anhydride and sulfuric acid to roughen the surface of the adhesive layer. Subsequently, the plate was immersed in an acidic aqueous solution containing a sensitizer (HS 101B manufactured by Hitachi Chemical Co., Ltd.) as a catalyst for chemical plating for 10 minutes, washed with water, and treated with diluted hydrochloric acid for 3 to 6% by weight for 5 minutes. After washing with water and drying at 120 ° C. for 20 minutes. The plates were cut out to a size of 16② × 10② to obtain test substrates of 16② × 10② respectively.

These 30 test substrates were attached with photosensitive elements already prepared in a conventional manner. Light emitted from the ultra-high pressure mercury lamp was applied in an amount of 400 mJ / I through the test negative mask shown in FIG. In Fig. 2, reference numeral 21 denotes an opacity portion of the negative mask, reference numeral 22 denotes a transparent portion of the negative mask, and the unit of numerical value is ①. Then, each substrate was heated at 80 ° C. for 5 minutes, left at room temperature for 20 minutes, the polyester film was peeled off as a known film, and the substrate was developed by spraying with 1, 1, 1-trichloroethane, which was 80 It dried at 10 degreeC. Subsequently, ultraviolet rays emitted from the ultra-high pressure mercury lamp were irradiated on the entire surface of the test substrate in an amount of 3 J / I. Thus, thirty test substrates having a negative pattern of the photosensitive resin composition were prepared.

These substrates were immersed in a chemical copper plating solution having the following composition for 12 hours at 70 ° C. for electroless copper plating to deposit copper having a thickness of about 30 μm on portions other than the negative patterns on the surfaces of the substrates. At the same time, the 16 × 10 × 10 ① stainless steel sheet was polished with abrasive paper 500, and the polished stainless steel sheet was subjected to sensitization with a commercially available catalyst solution (HS 101B of Hitachi Chemical Co., Ltd.), and similarly electroless copper plating was performed. After plating, the copper foil formed by plating was gently peeled from the stainless steel sheet and cut into width 1② to obtain a tensile specimen.

[Chemical Concentration Amount]

Copper sulfate pentahydrate 10 g / II

Ethylenediaminetetraacetic acid 30 g / II

37% formalin 3 III / II

pH (adjusted sodium hydroxide) 12.5

Polyethylene Glycol (m.w. = 600) 20 III / II

2,2'-dipyridyl 30 III / II

High precision negative masks were reproduced on all 30 test substrates to obtain a copper plating pattern. Using copper sheet DSS-5000 manufactured by Shimadzu Corp., a tensile test was performed on copper foil formed on stainless steel sheet at a tensile speed of 2① and a chuck spacing of 50① to measure copper mechanical properties. Elongation was 9.2% and bending number 6 was good mechanical properties.

Example 2

The same procedure as in Example 1 except that 25 parts of trimethylolpropane trimethacrylate and 25 parts of trimethylolpropane triacrylate were used instead of 46 parts of trimethylolpropane trimethacrylate and 4 parts of trimethylolpropane triacrylate. Was carried out. A high precision copper plating pattern was obtained. The mechanical properties of copper were good at 7.5% of the new stream and 5 bending times.

Example 3

20 parts of trimethylolpropane trimethacrylate and 10 parts of 2,2'-bis (4-methacryloxydiethoxyphenyl) propane instead of 46 parts of trimethylolpropane trimethacrylate and 4 parts of trimethylolpropane triacrylate. The same procedure as in Example 1 was carried out except that 20 parts of KAYARADIV R-604 (acrylate monomer manufactured by NIPPON KAYAKU CO, LTD.) Was used. A high precision copper plating pattern was obtained. The mechanical properties of copper were good at 10.0% elongation and 6 bending times.

Example 4

Instead of 46 parts of trimethylolpropane trimethacrylate and 4 parts of trimethylolpropane triacrylate, 30 parts of dipentaerythritol hexamethacrylate, 10 parts of tetrahydrofurfuryl methacrylate, and trimethylolethane triacrylate 10 The same procedure as in Example 1 was carried out except that parts were used. A high precision copper plating pattern was obtained. The mechanical properties of copper were good at an elongation of 9.5% and a bending number of six.

Example 5

Trimethylolpropane trimethacrylate 20 parts

5 parts of 2,2'-bis (4-methacryloxydiethoxyphenyl) propane

20 parts trimethylolpropane triacrylate

Methyl methacrylate-styrene-butadiene

(65/24/11 weight ratio) 55 parts of copolymers

Benzophenone part 3

0.1 part of 4,4'-bis (diethylamine) benzophenone

Victoria Pure Blue Part 0.01

Toluene 50 parts

Methyl ethyl ketone 50 parts

The same procedure as in Example 1 was carried out except that the photosensitive resin composition solution of the composition was used. A high precision copper plating pattern was obtained. The mechanical properties of copper were good at 8.7% elongation and 6 bending times.

Example 6

Methyl methacrylate-tetrahydrofurfuryl methacrylate-methacrylate-2-hydroxyethyl methacrylate (82/15/1/2 parts by weight) instead of 55 parts of methyl methacrylate-styrene-butadiene copolymer The same procedure as in Example 5 was conducted except that 55 parts of the copolymer were used. A high precision copper plating pattern was obtained. The mechanical properties of copper were good at 8.2% elongation and 6 bending times.

Comparative Example 1

The same procedure as in Example 1 was carried out except that 46 parts of trimethylolpropane trimethacrylate and 50 parts of trimethylolpropane triacrylate were used instead of 4 parts of trimethylolpropane triacrylate. Copper formed by electroless plating was not good at an elongation of 3.2% and bending number 3 times.

Comparative Example 2

Except for using 46 parts of trimethylolpropane trimethacrylate and 4 parts of trimethylolpropane triacrylate, 50 parts of urethane diacryl obtained by reacting 1 mole of isophorone diisocyanate and 2 mole of 2-hydroxyethyl acrylate were used. Performed the same process as in Example 1. Copper formed was 1.5% elongation and the number of bending was 1, the mechanical properties were not good.

Comparative Example 3

Use of 50 parts of urethane dimethacrylate obtained by reacting 1 mole of toylene diisocyanate and 2 moles of 2-hydroxyethyl methacrylate instead of 46 parts of trimethylolpropane trimethacrylate and 4 parts of trimethylolpropane triacrylate. Except for the same process as in Example 1. The mechanical properties of the formed copper were not good, with an elongation of 2.1% and a bending number of 1.

Example 7

80 parts pentaerythritol tetramethacrylate

20 parts trimethylolpropane triacrylate

α, α-dimethoxy-α-phenylacetophenone3part

Methyl ethyl ketone 20 parts

The photosensitive resin composition solution was applied to 30 commercially available substrates as in Example 1 by the dip coating method. The applied substrate was dried at 80 ° C. for 10 minutes. After drying, the thickness of the photosensitive resin composition layer was about 20 micrometers. On this layer was attached a polyethylene terephthalate film having a thickness of 25 µm. The other procedure was performed similarly to Example 1, and obtained the high precision copper plating pattern. The mechanical properties of the copper were good at 7.4% elongation and 5 bending times.

As can be seen from the above embodiment, the manufacturing method of the printed circuit board according to the present invention provides a high precision printed circuit board having good copper plating property by the additive method.

In addition, since the contamination of the plating solution hardly occurs in the process of the present invention, it is possible to mass-produce a printed circuit board having excellent characteristics.

The foregoing are merely some embodiments of the present invention, and various modifications and variations can be made without departing from the spirit and scope of the present invention.

Claims (6)

(1) A nitrogen atom directly bonded to at least one hydrogen atom in the molecule with (A) (a) at least one terminal methacryloyl group on the surface of the substrate (necessary portion where copper should be precipitated by electroless plating). 5 to 99% by weight of at least one type of unsaturated compound not having, and (b) at least one type of unsaturated compound having from at least one terminal acryloyl group and having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule. 100 parts by weight of the photopolymerizable mixed component constituting 1% by weight, (B) 0 to 400 parts by weight of the linear polymer compound having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule, and (C) upon irradiation of the actinic light Forming a photosensitive resin composition layer containing 0.5 to 20 parts by weight of a sensitizer and / or a sensitizer to produce free radicals, and (2) an image on the photosensitive resin composition Irradiating and developing phosphorus actinic light to form a negative pattern of the photosensitive resin composition on the surface of the substrate, and (3) electroless copper plating on the substrate using the negative pattern of the photosensitive resin composition as the plating resist. And forming a circuit pattern on the surface of the substrate. The method of manufacturing a printed circuit board according to claim 1, wherein the linear polymer compound (B) having no nitrogen atom directly bonded to at least one hydrogen atom in the molecule has at least one tetrahydrofurfuryl group as a side chain. The method of manufacturing a printed circuit board according to claim 1, wherein the step of forming the photosensitive resin composition layer is carried out by laminating photosensitive elements on the surface of the engine. The method of manufacturing a printed circuit board according to claim 2, wherein the step of forming the photosensitive resin composition layer is carried out by laminating photosensitive elements on the surface of the substrate. The method of manufacturing a printed circuit board according to claim 1, further comprising re-irradiating actinic light on the surface of the substrate after the development (step (2)). The method of claim 1, wherein at least one unsaturated compound having at least one terminal methacryloyl group and not having a nitrogen atom directly bonded to at least one hydrogen atom in the molecule does not include an oxygen atom directly bonded to a hydrogen atom. Method of manufacturing a printed circuit board, characterized in that.

Images