JPH09263727A - Resin composition for protecting metal surface, and production of laminate and printed circuit board using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin compsn. for protecting a metal surface which enables the exposure of the B-side to be omitted and cab greatly reduce the number of defective products by compounding a specific copolymer with a dipentaerythritol deriv. and an acid ester of ethylene glycol. SOLUTION: This compsn. comprises 50-80 pts.wt. copolymer (A), 20-50 pts.wt. dipemtaerythritol deriv. (B), and 1-20 pts.wt. acid ester of ethylene glycol (C), the sum of ingredients A and B being 100 pts.wt. The copolymer is produced from 4-12mol.% at least one polymerizable carboxylated vinyl monomer, 10-30mol.% at least one 3-8C alkyl (meth)acrylate, and 58-86mol.% alkyl acrylate having a 1 or 2C alkyl group (the sum of all the monomers being 100mol.%) and has a wt. average mol.wt. of 30,000-400,000. The deriv. is represented by formula I (wherein R<1> to R<6> are each H, methyl, ethyl, etc.). The ester is represented by formula II (wherein R<11> and R<12> are each H or methyl, R<13> and R<14> are each methyl, ethyl, propyl, etc,; and (n) is 3-9).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a metal surface protective resin composition, a laminate using the same, and a method for producing a printed circuit board.

[0002]

2. Description of the Related Art As a copper clad laminate used for manufacturing a printed circuit board, one having a structure in which copper foil is laminated on both surfaces of a glass cloth-epoxy resin sheet is widely used. In addition, a photosensitive resin composition is widely used as a resist used for manufacturing a printed circuit board, and a photosensitive laminate (hereinafter referred to as a photosensitive film) obtained by coating and drying the photosensitive resin composition on a support is used. ) Is also widely used. The mainstream of these photosensitive films is the alkaline type, in which the uncured portion is soluble in a weak alkaline aqueous solution and thus developable, and the cured portion is removable in a strong alkaline aqueous solution.

In a printed circuit board, a photosensitive layer of a photosensitive film is laminated on a copper clad laminate which has been polished or treated with chemicals, and then a circuit pattern is cured by exposure through a photo tool, and then the support is removed. The uncured portion is developed using a weak alkaline aqueous solution such as a 0.5 to 2.0 wt% sodium carbonate aqueous solution to form a resist image (cured portion) on the copper clad laminate. Then, after the exposed copper surface outside the resist image area is removed by etching with an etching solution, 1.0 to 5.0% by weight
The resist image is peeled off using a strong alkaline aqueous solution of sodium hydroxide or the like to produce a printed circuit board.

The conventional printed circuit board is mainly a printed circuit board in which a circuit is formed on both sides of a copper clad laminate or a circuit is formed on only one side of the copper clad laminate. In the process of manufacturing multilayer printed wiring boards,
There is a demand for the production of a printed circuit board for producing a multilayer printed wiring board in which a circuit is formed on one side of a copper clad laminate and a copper foil is left on the other side. In order to meet this requirement, in the conventional method, photosensitive layers of a photosensitive film are laminated on both surfaces of a copper clad laminate, and then one side (hereinafter referred to as A side) is cured by exposing a circuit pattern through a photo tool and then the other side. The surface (hereinafter referred to as surface B) was entirely cured by exposure to light, and then developed, etched, and peeled off to manufacture a printed circuit board for manufacturing a multilayer printed wiring board.

During the exposure in the above manufacturing process, if a foreign substance or the like is present on the surface B, the existing portion of the foreign substance or the like is not exposed and becomes uncured, and the uncured portion is developed to remove the resist. The copper in that portion is etched during the etching process, resulting in a fatal defect.

[0006]

The invention according to claim 1 provides a metal surface protective resin composition which can omit the exposure of the B side and can significantly reduce defects due to the inclusion of foreign matters and the like. is there. The invention according to claim 2 provides a laminate capable of omitting the exposure of the surface B and significantly reducing defects due to the inclusion of foreign matters and the like, and using it to manufacture a printed circuit board with good workability. is there. The invention according to claim 3 provides a method for manufacturing a printed circuit board, which has good workability and can achieve a high yield.

[0007]

The present invention provides (A) and (a)
4-12 mol% of at least one vinyl-polymerizable first monomer having a carboxyl group, and (b) Tg of homopolymer
Has an alkyl group having a carbon number of 3 to 8 at 70 ° C. or lower,
At least one second monomer 10 selected from the group consisting of alkyl acrylates and alkyl methacrylates;
30 mol% and (c) an alkyl acrylate or alkyl methacrylate having an alkyl group having 1 to 2 carbon atoms,
At least one selected from the group consisting of hydroxyalkyl acrylate and hydroxyalkyl methacrylate
58-86 mol% of the third monomer of the species (however, (a) +
(B) + (c) is 100 mol%) and has a weight average molecular weight of 30,000 to 400,000.
50 to 80 parts by weight of a copolymer having 0 (provided that the total amount of the components (A) and (B) is 100 parts by weight), (B) general formula (I)

Embedded image (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently

[Chemical 6] (In the formula, R ⁷ represents —H or —CH ₃ , and R ⁸ , R ⁹ and R
¹⁰ independently represents -H or -CH ₃ , and m is 1 to
Which is an integer of 3) 20) to 50)
Parts by weight (however, the total amount of the components (A) and (B) is 10
0 parts by weight) and (C) general formula (II)

Embedded image (In the formula, R ¹¹ and R ¹² are each independently —H or —CH.
₃ , R ¹³ and R ¹⁴ are each independently

Embedded image (Wherein R ¹⁵ represents —H or —CH ₃ ) and n is an integer of 3 to 9) 1 to 20 parts by weight (however, the component (A) and the component (B)). The present invention relates to a metal surface protecting resin composition containing 100 parts by weight of the total amount of components), which is insoluble in a weak alkaline aqueous solution and peels off in a strong alkaline aqueous solution.

The present invention also relates to a laminate obtained by applying the above-mentioned metal surface protection resin composition onto a support and drying it.
In addition, the present invention, after the step of laminating the photosensitive film on one side (A side) of the copper clad laminate and the step of laminating the laminate according to claim 2 on the other side (B side),
A surface is exposed in a pattern and is exposed to A with a weak alkaline aqueous solution.
The present invention relates to a method for manufacturing a printed circuit board, which comprises developing an unexposed portion of a surface, etching the surface, and then peeling off the resin on the surface A and the surface B with a strong alkaline aqueous solution.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the components contained in the metal surface protective resin composition of the present invention will be described in detail. The vinyl-polymerizable first monomer (a) used in the copolymer (A) in the present invention imparts releasability to the copolymer (A) and has one ethylenically unsaturated group. Carboxylic acid (for example, acrylic acid, methacrylic acid, fumaric acid, cinnamic acid,
Crotonic acid, propiolic acid, itaconic acid, maleic acid, etc.) or acid anhydride derivatives (eg, maleic anhydride,
Maleic acid half ester etc.), and among them, methacrylic acid is preferable. The amount of the (a) first monomer used in the copolymer (A) in the present invention is 4 to 12 mol%.
And is preferably 5 to 8 mol%. If the amount used is less than 4 mol%, it will be difficult to peel off with a strong alkaline aqueous solution, and if it exceeds 12 mol%, it will be dissolved in a weak alkaline aqueous solution.

The second monomer (b) used in the copolymer (A) in the present invention imparts releasability, flexibility, and chemical resistance to an etching treatment liquid to the copolymer (A). Alkyl acrylates and alkyl methacrylates (for example, propyl acrylate, butyl acrylate, octyl acrylate, corresponding methacrylates, etc.) having a Tg of a homopolymer of 70 ° C. or less and having an alkyl group having 3 to 8 carbon atoms. Selected from the group consisting of. The amount used is 10 to 30 mol%.
Since the amount of the (b) second monomer has a close relationship with the peelability with the first monomer, if the amount of the (b) second monomer exceeds 30 mol%, Even if the content of the carboxyl group of the polymer is in the range of 4 to 12 mol%, the releasability is poor. If it is less than 10 mol%, the above-mentioned chemical resistance,
Peelability is poor. Tg of the homopolymer is 70 ° C or lower (b)
The second monomer is used because T of the resulting copolymer (A) is
This is because g is lowered to obtain a preferable range.

The (c) third monomer used in the copolymer (A) in the present invention imparts adhesiveness to the metal plate of the resist and has an alkyl acrylate (having an alkyl group having 1 to 2 carbon atoms). For example, it is selected from the group consisting of methyl acrylate, ethyl acrylate, etc.), hydroxylalkyl acrylate (eg, hydroxylmethyl acrylate, hydroxylethyl acrylate, etc.), and corresponding methacrylates, and among them, methyl methacrylate is preferable. The amount of component (c) used is 5
It is 8 to 86 mol%. If the amount used is less than 58 mol%, the adhesion will be poor, and if it exceeds 86 mol%, the peelability and chemical resistance will be poor.

The molecular weight of the copolymer (A) is a factor that imparts film-forming property and further determines resistance to a developing solution, a processing solution and a stripping solution. The range of this weight average molecular weight (value measured by gel permeation chromatography and converted into standard polystyrene) is 30,000 to 40.
It is 50,000, preferably 50,000 to 300,000. When the weight average molecular weight is less than 30,000, the film-forming property is impaired and the resistance to the weak alkaline aqueous solution is lowered, and when it exceeds 400,000, the film-forming property and the resistance are very good, Peeling becomes difficult. From the viewpoint of film flexibility, the Tg of the copolymer is preferably in the range of 60 to 100 ° C.

Examples of the compound (B) represented by the general formula (I) in the present invention include dipentaerythritol,
Dipentaerythritol monomethyl ether, dipentaerythritol dimethyl ether, dipentaerythritol trimethyl ether, dipentaerythritol tetramethyl ether, dipentaerythritol pentamethyl ether, dipentaerythritol hexamethyl ether, dipentaerythritol monoethyl ether, dipentaerythritol diethyl ether , Dipentaerythritol triethyl ether, dipentaerythritol tetraethyl ether, dipentaerythritol pentaethyl ether, dipentaerythritol hexaethyl ether, dipentaerythritol monopropyl ether, dipentaerythritol dipropyl ether, dipentaerythritol tripropyl ether, dipenta Erythritole Lapropyl ether, dipentaerythritol pentapropyl ether, dipentaerythritol hexapropyl ether, dipentaerythritol monoacetate, dipentaerythritol diacetate, dipentaerythritol triacetate, dipentaerythritol tetraacetate, dipentaerythritol pentaacetate, dipentaerythritol Hexa acetate, dipentaerythritol monopropionate, dipentaerythritol dipropionate, dipentaerythritol tripropionate, dipentaerythritol tetrapropionate, dipentaerythritol pentapropionate, dipentaerythritol hexapropionate, dipentaerythritol hexapropionate Pentaerythritol monobutyrate, dipentaerythritol dib Acrylate, dipentaerythritol tri butyrate, dipentaerythritol tetrabutylate, dipentaerythritol pentabutyrate acrylate, dipentaerythritol hexa butyrate,
Dipentaerythritol monoacrylate, dipentaerythritol diacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, monoacrylate of ethylene oxide adduct of dipentaerythritol, dipentaerythritol Ethylene oxide adduct diacrylate, dipentaerythritol ethylene oxide adduct triacrylate, dipentaerythritol ethylene oxide adduct tetraacrylate, dipentaerythritol ethylene oxide adduct pentaacrylate, dipentaerythritol ethylene oxide adduct hexaacrylate Acrylate, dipentaerythritol Propylene oxide adduct monoacrylate, dipentaerythritol propylene oxide adduct diacrylate, dipentaerythritol propylene oxide adduct triacrylate, dipentaerythritol propylene oxide adduct tetraacrylate, dipentaerythritol propylene oxide There are pentaacrylate as an adduct, hexaacrylate as a propylene oxide adduct of dipentaerythritol, and methacrylate corresponding to the above. A monomer (fourth monomer) other than the first monomer, the second monomer and the third monomer can be used as long as the effect of the present invention is not impaired.

The content of the copolymer (A) contained in the metal surface protective resin composition of the present invention is 50 to 80 parts by weight (provided that the total amount of the components (A) and (B) is the same). 100
Parts by weight). When the content of the component (A) is less than 50 parts by weight, the resin layer softens and cold flow occurs during storage, and when it exceeds 80 parts by weight, the resin layer becomes brittle and easily peels off before lamination. . The content of the ethylenically unsaturated compound (B) contained in the metal surface protection resin composition of the present invention is 20 to 50 parts by weight (however,
The total amount of the components (A) and (B) is 100 parts by weight). When the content of the component (B) is less than 20 parts by weight, the resin layer becomes brittle and easily peels off before laminating, and when it exceeds 50 parts by weight, the resin layer is softened and cold flow occurs during storage. .

Examples of the compound (C) represented by the general formula (II) in the present invention include polyethylene glycol diacetate (having 3 to 9 ethylene groups), polyethylene glycol dipropionate (number of ethylene groups). Of 3 to 9), polyethylene glycol dibutyrate (having 3 to 9 ethylene groups), polypropylene glycol diacetate (having 3 to 9 propylene groups), polypropylene glycol dipropionate (propylene group) Of 3 to 9), polypropylene glycol dibutyrate (having 3 to 9 propylene groups), polyethylene glycol di (meth) acrylate (having 3 to 9 ethylene groups), polypropylene glycol di (Meth) acrylate (having 3 to 9 propylene groups), etc. That.

The content of the compound (C) represented by the general formula (II) contained in the metal surface protection resin composition of the present invention is
The amount is 1 to 20 parts by weight based on 100 parts by weight of the total amount of the copolymer (A) and the compound (B) represented by the general formula (I). When the content of the component (C) is less than 1 part by weight,
The adhesion between the resin layer and the metal surface is reduced and peeling easily occurs.
When it exceeds the weight part, the resin layer is softened and cold flow occurs.

Generally, in order to prevent thermal polymerization during the heating step and during storage, it is preferable to add a radical polymerization inhibitor to the resin layer (the addition amount is usually the component (A) and the component (B)). 0.1 to 100 parts by weight
5 parts by weight). Examples of the radical polymerization inhibitor include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, phenothiazine, pyridine,
Examples include nitrobenzene and dinitrobenzene,
It preferably has a low volatility of 200 ° C. or lower. As such, for example, alkyl-substituted hydroquinone, t-butylcatechol, cuprous chloride, 2,6-di-
t-butyl-p-cresol, 2,2-methylenebis
(4-ethyl-6-t-butylphenol), 2,2-
Examples thereof include methylenebis (2-methyl-6-t-butylphenol). Further, in order to improve the stability of the resist after being laminated on copper, a copper antioxidant such as benzotriazole, benzotriazole hydrochloride, benzotriazole organic acid salt or aminobenzothiazole may be added (the addition amount is , Usually 0.1 to 5 parts by weight based on 100 parts by weight of the total amount of (A) + (B)).

The metal surface protection resin composition of the present invention may contain a coloring substance such as a dye or a pigment (the addition amount is usually 100 parts by weight of the total amount of the components (A) and (B)). 0.1 to 30 parts by weight). It is preferable that the coloring substance does not affect the characteristics of the resist and does not decompose or volatilize at a temperature of 200 ° C. or lower. Examples of such a colorant include fuchsin, auramine base, chalcocide green S, paramagenta, crystal violet, methyl orange, Nile blue 2B, Victoria blue, malachite green, basic blue 20, iodin green, night green B, Trivalosan, New Magenta, Acid Violet RRH,
Red Violet 5RS, New Methylene Blue GG
And the like. Moreover, you may add additives, such as an adhesion promoter, to the metal surface protection resin composition of this invention.

The laminate of the present invention can be manufactured as follows. First, the metal surface protection resin composition is uniformly dissolved in a solvent. The solvent is not particularly limited as long as it dissolves the metal surface protection resin composition, and one or several kinds of solvents may be used. Examples of the solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve, ethyl cellosolve, dichloromethane,
Chloroform, methyl alcohol, ethyl alcohol and the like can be mentioned. Then, the metal surface protection resin composition in the form of a solution is uniformly applied on a support with a roll coater or the like, and then dried by heating and / or blowing with hot air, and the solvent is removed to form a resin layer (dry film). To do. The thickness of the resin layer is not particularly limited and is preferably 10 to 100 μm, more preferably 15 to 60 μm. A laminate comprising two layers of a resin layer and a support can be stored as it is or by further laminating a protective film on the surface of the resin layer opposite to the surface on which the support is provided and winding it in a roll shape.

Examples of the support include films made of polyethylene terephthalate, polypropylene, polyethylene, polyvinyl chloride, polyvinylidene chloride and the like, and polyethylene terephthalate film is preferable. Since these must be removable from the resin layer later, they are materials that cannot be removed,
It must not be surface treated. The thickness of these films is preferably 5 to 100 μm, and 1
It is preferably from 0 to 30 μm. These films can be used as a protective film.

A printed circuit board for producing a multilayer printed wiring board in which a circuit is formed on the A side and a copper foil is entirely left on the B side can be manufactured as follows. If the protective film, if any, of the laminate of the present invention is removed, the resin layer is heated and pressure-bonded to the copper clad laminate B surface (for example, using a roll, 0.5-10 kgf / Laminate by pressing (cm ² ). Since it is necessary to form a circuit on the A side, a photosensitive film conventionally used for manufacturing a printed circuit board is used.
Lamination is performed by the same method as the above laminating method.
Next, the surface A is exposed in a circuit pattern through a photo tool, and the surface B is not exposed. Then, if a support is present on the surface of the photosensitive film or laminate, the support is removed and a weak alkaline aqueous solution such as 0.5 to 3.0% by weight of sodium carbonate is used, and a known method, for example, A, by spraying, rock dipping, scraping, etc.
Develop the unexposed areas of the surface. At this time, the resin layer on the B side remains without being developed. Then, after performing an etching treatment, the resin layer on the A side and the B side is peeled off using a strong alkaline aqueous solution such as 1.0 to 5.0% by weight of sodium hydroxide.

[0022]

EXAMPLES The present invention will be described below with reference to examples. Example 1 The materials shown in Table 1 were blended to prepare a metal surface protection resin composition, which was evenly applied onto a polyethylene terephthalate film having a thickness of 20 μm, and then dried with a hot air convection dryer at 100 ° C.
It was dried for a minute to form a laminate. The thickness of the resin layer after drying is 2
It was 5 μm.

Then, the resin layer was laminated on a copper clad laminate having a clean surface by heating and pressing with a rubber roll so that the resin layer was in contact with the copper surface. After that, the polyethylene terephthalate film was removed, and the mixture was washed with 1.0% by weight sodium carbonate aqueous solution.
Spray development for 00 seconds, with cupric chloride etchant,
After spray-etching for 500 seconds, spray-peeling was performed for 50 seconds with a 3.0 wt% sodium hydroxide aqueous solution.
As a result, the resin composition was not attacked by the developing solution and the etching solution and could be peeled off by the peeling solution. Further, as a result of examining the occurrence of cold flow by winding the laminated body 200 m in a roll shape, no bleeding of the resin layer from the end portion of the laminated body was observed even after standing for 5 months.

[0024]

[Table 1]

Comparative Example 1 A metal surface protecting resin composition was prepared in the same manner as in Example 1 except that the copolymer A in Table 1 was changed to the copolymer B shown in Table 2. It evaluated by the same method. As a result, the composition was not attacked by the developing solution or the etching solution, but could not be removed by the removing solution.

[0026]

[Table 2]

Comparative Example 2 A metal surface protecting resin composition was prepared in the same manner as in Example 1 except that the copolymer C in Table 1 was changed to the copolymer C shown in Table 3. It evaluated by the same method. As a result, the composition was attacked by the developer.

[0028]

[Table 3]

Comparative Example 3 A metal surface protective resin composition was prepared in the same manner as in Example 1 except that the copolymer A in Table 1 was changed to the copolymer D shown in Table 4. It evaluated by the same method. As a result, the composition was not attacked by the developing solution or the etching solution, but could not be removed by the removing solution.

[0030]

[Table 4]

Comparative Example 4 A metal surface protecting resin composition was prepared in the same manner as in Example 1 except that triethylene glycol diacetate was not added, and the same method as in Example 1 was used for evaluation. . As a result, the composition was not attacked by the developing solution and the etching solution, but the infiltration of the developing solution and the etching solution was observed, which was considered to be caused by the insufficient adhesion of the composition to copper.

Comparative Example 5 A metal surface protecting resin composition was prepared in the same manner as in Example 1 except that the blending amount of triethylene glycol diacetate was changed to 30 parts by weight.
The evaluation was performed in the same manner as described above. As a result, the composition is not attacked by the developing solution and the etching solution, and
It could be peeled off by the peeling liquid. However, as a result of examining the occurrence of cold flow by winding the laminated body 200m in a roll shape, the resin layer leached from the end portion of the laminated body when left for one month.

Comparative Example 6 A metal surface protective resin composition was prepared in the same manner as in Example 1 except that the dipentaerythritol hexaacrylate was changed to tetraethylene glycol diacrylate, and the same method as in Example 1 was used. Was evaluated. As a result, the composition was attacked by the developer.

Comparative Example 7 A metal surface was prepared in the same manner as in Example 1 except that polyethylene glycol diacrylate (trade name A-14G manufactured by Shin-Nakamura Chemical Co., Ltd.) was used in place of dipentaerythritol hexaacrylate. The protective resin composition was prepared and evaluated in the same manner as in Example 1. As a result, the composition was attacked by the developer.

Comparative Example 8 Evaluation was made in the same manner as in Example 1 except that dimethylolpropane triacrylate was used instead of dipentaerythritol hexaacrylate in Example 1. As a result, the composition was attacked by the developer.

[0036]

The invention according to claim 1 provides a metal surface protective resin composition which can omit the exposure of the B side and can significantly reduce defects due to the inclusion of foreign matters and the like.
A method for manufacturing a laminate and a printed circuit board using the same is provided. The invention according to claim 2 provides a laminate capable of omitting the exposure of the surface B and significantly reducing defects due to the inclusion of foreign matters and the like, and using it to manufacture a printed circuit board with good workability. is there. The invention according to claim 3 provides a method for manufacturing a printed circuit board, which has good workability and can achieve a high yield.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hajime Kakumaru 4-13-1, Higashimachi, Hitachi-shi, Ibaraki Hitachi Chemical Co., Ltd. Yamazaki factory

Claims (3)

[Claims] 1. (A) (a) 4 to 12 mol% of at least one vinyl-polymerizable first monomer having a carboxyl group
And (b) the homopolymer has a Tg of 70 ° C. or less and a carbon number of 3
10 to 30 mol% of at least one second monomer selected from the group consisting of alkyl acrylates and alkyl methacrylates having 1 to 8 alkyl groups, and (c) an alkyl group having 1 to 2 carbon atoms. At least one third monomer 58 to 8 selected from the group consisting of acrylate, alkyl methacrylate, hydroxyalkyl acrylate and hydroxyalkyl methacrylate.
A copolymer with 6 mol% (however, (a) + (b) + (c) is 100 mol%) having a weight average molecular weight of 3
Copolymer 50-80, which is 20,000-400,000
Parts by weight (however, the total amount of the components (A) and (B) is 10
0 parts by weight), (B) General formula (I) (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently (In the formula, R ⁷ represents —H or —CH ₃ , and R ⁸ , R ⁹ and R
¹⁰ independently represents -H or -CH ₃ , and m is 1 to
Which is an integer of 3) 20) to 50)
Parts by weight (however, the total amount of the components (A) and (B) is 10
0 part by weight) and (C) general formula (II) (In the formula, R ¹¹ and R ¹² are each independently —H or —CH.
₃ and R ¹³ and R ¹⁴ are each independently (Wherein R ¹⁵ represents —H or —CH ₃ ) and n is an integer of 3 to 9) 1 to 20 parts by weight (however, the component (A) and the component (B)). A metal surface protective resin composition containing 100 parts by weight of the components), which is insoluble in a weak alkaline aqueous solution and peels off in a strong alkaline aqueous solution. 2. A laminate obtained by applying the metal surface protection resin composition according to claim 1 on a support and drying the composition. 3. After the step of laminating the photosensitive film on one side (A side) of the copper clad laminate and the step of laminating the laminate according to claim 2 on the other side (B side), A
The printed circuit is characterized in that the surface is exposed in a pattern, the unexposed portion of the surface A is developed with a weak alkaline aqueous solution, and after the etching treatment, the resin on the surface A and the surface B is peeled off with a strong alkaline aqueous solution. Board manufacturing method.