JPH0846329A - Manufacture of printed wiring board - Google Patents

Abstract

PURPOSE:To protect fully a metal conductive layer in a through hole by a method wherein the interior of at least the through hole is filled with alkali- soluble ink before a photoconductive layer is provided. CONSTITUTION:A through hole 1 is bored in a laminated board formed by providing each first metal conductive layer 12 on both surfaces of an insulating substrate 11 and after a second metal conductive layer 13 is made to deposit on the part of the substrate 11 in the interior of the hole 1 and the surfaces of the layers 12 by a metal plating method, the interior of the hole 1 is filled with ink 23. Then, a photoconductive layer 21 is formed on the part of the ink 23 and the layer 13 and after the surface of the layer 21 is evenly electrified in the dark, an exposure is performed to obtain an electrostatic latent image. Moreover, a toner layer 22 equivalent to a circuit part is formed on the layer 21 by an electrophotographic normal developing method and the layer 21 other than the layer 22 is eluted and removed. Thereby, the second metal conductive layer in the part of the through hole can be easily protected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a printed wiring board using electrophotography, and more particularly to a method for manufacturing a printed wiring board having through holes.

[0002]

2. Description of the Related Art In the manufacture of a printed wiring board by the subtractive method, a laminated board in which a metal conductive layer such as a copper foil is laminated on an insulating substrate is provided with a resist for protecting the metal conductive layer in a portion corresponding to a circuit portion. It is provided and the unnecessary metal conductive layer is removed by etching. A photopolymer is generally used as a resist material. At present, a printed wiring board is required to have a high density wiring pattern, which requires a resist image having a high resolution. An exposure process is an example of a process that affects the resolution. Generally, as a photopolymer exposure method, a contact exposure method using ultraviolet light through a photomask has been performed, but it takes time to manufacture the photomask, the delivery time cannot be shortened, and it is not possible to support a large variety of small lots. There is a problem that an image is missing due to dust between the photomask and the photopolymer. Therefore, a shift to a direct scanning exposure method for a photopolymer using a laser beam is attempted.

The laser exposure method using a photopolymer has been put to practical use by using a dry film photoresist and an electrodeposition photoresist. However, the photopolymer has an extremely low optical sensitivity of 1 to several 100 mJ / cm ^2, and in order to compensate for this, it is necessary to increase the output of the laser beam or lengthen the exposure time, and in reality, it is efficient. It was difficult to manufacture a printed wiring board.

Therefore, West German Patent Nos. 1117391, 2526720, 3210577, and Japanese Patent Laid-Open No. 5-51987.
No. 2-2437, No. 57-48736, No. 59-16.
Nos. 8462 and 63-129689 propose electrophotographic photoreceptors as resist materials having high optical sensitivity and being compatible with scanning exposure with laser light. The electrophotographic photoreceptor has an optical sensitivity of several to several tens of μJ / cm ² , although it varies depending on the wavelength of the photoconductive compound and the laser beam.

A method of manufacturing a printed wiring board having through holes using an electrophotographic photosensitive member is disclosed in Japanese Patent Publication No. 1-35.
It is proposed in Japanese Patent No. 518. As shown in Figure 1,
First, after providing the photoconductive layer 21 on the inside of the through hole 1 and on the surface of the laminated plate (FIG. 1 (b)), the laminated plate (FIG. 1 (a)) in which the through hole 1 is opened and subjected to the metal plating treatment,
The surface of the laminated plate is uniformly charged in the dark (Fig. 1 (c)) and exposed as shown in Fig. 1 (d), and the non-exposed part where the electric charge remains and the part of the through hole have opposite polarities by electrophotography. The toner layer 22 corresponding to the circuit portion is formed on the inside of the through hole 1 and on the surface of the photoconductive layer 21 (FIG. 1).
(E)). After that, the toner layer 22 is used as a resist to elute and remove the portion of the photoconductive layer 21 not covered with the toner layer 22 (FIG. 1F), and then the remaining toner layer 2 is removed.
2 and the metal conductive layer 13 under the metal conductive layer 13 exposed by using the photoconductive layer 21 thereunder as an etching resist.
Is removed by etching (FIG. 1 (g)), and the etching resist is peeled off (FIG. 1 (h)).
A metal wiring pattern is formed on top.

[0006]

In the printed wiring board manufacturing method described above, a coating method such as a dipping method or a spray method is used to cover the inside of the through hole. However, in the dipping method, setting the coating conditions to make the film thickness uniform is troublesome, and in the spray method, the coating efficiency is 50%.
There was a drawback that it was as low as%. In addition, when the diameter of the through hole becomes smaller, conditions such as coating liquid property and coating device are limited in order to put the coating liquid into the hole by either method, and it is easy to form the photoconductive layer in the through hole. I can't
It was not possible to sufficiently protect the metal conductive layer in the through hole.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that through holes are formed in a laminated plate provided with a first metal conductive layer on both surfaces of an insulating substrate.
After performing a metal plating treatment to provide a second metal conductive layer inside the through hole and on the surface of the laminated plate, a photoconductive layer is formed on the second metal conductive layer, and then a circuit portion is formed on the circuit portion by electrophotographic positive development. A corresponding toner layer is formed, the photoconductive layer other than the toner layer portion is eluted and removed to form an etching resist composed of the toner layer and the photoconductive layer, and then the exposed second metal conductive layer and first metal are exposed. In the method for manufacturing a printed wiring board in which the conductive layer is removed by etching, and the remaining etching resist is further removed if necessary, at least the inside of the through hole is filled with an alkali-soluble ink before providing the photoconductive layer. I found good things.

Furthermore, a through hole is opened in the laminated plate having the first metal conductive layer on both sides of the insulating substrate, and a metal plating process is performed to form a second hole inside the through hole and on the surface of the laminated plate.
After the metal conductive layer is formed, the inside of the through hole is filled with ink, the photoconductive layer is formed on the ink layer formed on the second metal conductive layer, and then the circuit portion is formed by the electrophotographic positive development method. Forming a toner layer corresponding to the above, and eluting and removing the photoconductive layer other than the toner layer portion to form an etching resist composed of the toner layer and the photoconductive layer, and then exposing the exposed second layer.
It was found that the metal conductive layer and the first metal conductive layer of 1) may be removed by etching, and the remaining etching resist may be removed depending on the case.

According to the present invention, the through hole can be easily protected by filling the through hole portion with the alkali-soluble ink. Various known coating methods can be used as the coating method for the photoconductive layer.
In the latter method, the ink is filled in the through hole and is also provided as an ink layer on the surface of the second metal conductive layer. However, by making the ink layer more soluble in the eluent than the photoconductive layer, A resist image with small side etching can be produced. Further, by setting the electric conductivity of the ink layer to 10 ^-9 S / cm or more, a high resolution can be obtained without adversely affecting electrophotographic characteristics such as photoconductivity of the photoconductive layer provided on the ink layer. A toner layer can be produced, and as a result, a high-quality printed wiring board can be produced.

The present invention will be described in detail below with reference to FIGS. 2 and 3. In the present invention, as shown in FIG. 2, a through hole 1 having a desired size is opened in a laminated plate in which a first metal conductive layer 12 is provided on an insulating substrate 11, and the insulating property inside the through hole 1 is formed by a metal plating method. After depositing the second metal conductive layer (metal plating layer) 13 on the substrate 11 and the surface of the first metal conductive layer 12 (FIG. 2A), the inside of the through hole 1 is filled with the ink 23 (FIG. 2). 2 (b)). Next, the photoconductive layer 2
1 is produced on 23 parts of the ink and the second metal conductive layer 13 (FIG. 2C). After uniformly charging the surface of the photoconductive layer 21 in the dark (FIG. 2 (d)), the exposure (FIG. 2 (e)) erases the charge in the portion corresponding to the circuit portion to obtain an electrostatic latent image. . Further, a toner layer 22 corresponding to a circuit portion is formed by electrophotographic normal development using toner having a polarity opposite to that of the electrostatic latent image.
Are formed on the photoconductive layer 21 (FIG. 2F). The photoconductive layer 21 other than the toner layer 22 is eluted and removed (FIG. 2 (g)),
Remaining toner layer 22, photoconductive layer 21 and ink 23
As a resist layer, the first metal conductive layer 12 and the second metal conductive layer 12
The metal conductive layer 13 is etched (FIG. 2 (h)), and the resist layer is optionally removed (FIG. 2 (i)).

Further, as shown in FIG. 3, a through hole 1 having a desired size is opened in a laminated plate in which a first metal conductive layer 12 is provided on an insulating substrate 11, and an insulating property inside the through hole is formed by a metal plating method. A metal conductive layer (metal plating layer) 13 was deposited on the substrate 11 and the surface of the first metal conductive layer 12 (FIG. 3).
(A)) After that, the inside of the through hole 1 is filled with the ink 23, and the ink layer 24 is provided on the second metal conductive layer (FIG. 3B). Next, the photoconductive layer 21 is formed on the ink 23 part and the ink layer 24 (FIG. 3C). The surface of the photoconductive layer 21 was uniformly charged in the dark (FIG. 3 (d)).
Then, by exposing (FIG. 3 (e)), the charge in the portion corresponding to the circuit portion is erased to obtain an electrostatic latent image. Further, using a toner having a polarity opposite to that of the electrostatic latent image, the photoconductive layer 21 of the circuit portion is coated with the toner by electrophotographic positive development under application of a bias voltage (FIG. 3 (f)). Photoconductive layer 21 other than toner layer 22
And the ink layer 24 are removed by elution (FIG. 3 (g)), and the remaining toner layer 22, photoconductive layer 21, ink 23 and ink layer 24 are used as resist layers to form the first metal conductive layer 12 and the second metal. The conductive layer 13 is etched (see FIG.
(H)), and if necessary, the resist layer is removed (FIG. 3 (i)).

In the method for manufacturing a printed wiring board of the present invention,
Ink 2 that protects the metal conductive layer 13 formed inside the through-hole 1 against copper etching liquid
3 is filled in the through hole 1. In the method shown in FIG. 2, the ink 23 is filled only inside the through hole 1. The ink 23 adheres to the second metal conductive layer depending on the filling method, but it is removed by means such as polishing.

In the printed wiring board manufacturing method of the present invention shown in FIG. 3, the ink 23 is also formed on the second metal conductive layer. The photoconductive layer 21 is formed on the ink layer 24, and then the toner layer 22 is formed by the electrophotographic positive development method. In the toner layer formation by the electrophotographic positive development method, the photoconductive layer 21 is uniformly charged in the dark, and then the portion corresponding to the non-circuit portion is exposed to erase the electric charge. At this time, as the electric charge remaining in the exposed area is extremely close to 0 and the difference from the surface potential of the non-exposed area is larger, an image with higher resolution can be obtained by toner development. When the electric conductivity of the ink layer provided under the photoconductive layer is low, the charge disappearance rate of the photoconductive layer becomes slow, and particularly when the electric conductivity of the ink is less than 10 ⁻⁹ S / cm, The photosensitivity is more than double that of the photoconductive layer provided on the metal conductive layer, and the resolution of the toner layer is significantly reduced.

Further, in the method of manufacturing the printed wiring board shown in FIG. 3 of the present invention, the line width of the metal wiring pattern, the size and shape of the side etching, etc. are determined by the toner layer 22 and the photoconductive layer 2.
1 is greatly affected by the shape of the etching resist formed of the ink layer 24 and the ink layer 24. In order to improve the resolution of the metal wiring pattern, it is desirable to reduce the side etching of the etching resist. In the present invention shown in FIG. 3,
The ink layer 24 is provided on the second metal conductive layer, but since the solubility of the ink layer 24 in an eluate described later is higher than that of the photoconductive layer 21, elution failure is less likely to occur and side etching is prevented. Can be suppressed.

The ink relating to the method for producing a printed wiring board of the present invention is classified into three types, that is, a drying (air drying) type, an ultraviolet light curing type, and a thermosetting type, depending on the curing method.

As the dry ink according to the present invention, an ink obtained by kneading an alkali-soluble resin with an appropriate solvent is used. The alkali-soluble resin contains at least a monomer having an anionic functional group, and may be copolymerized with a nonionic monomer in order to impart toughness and adhesiveness. Examples of the anionic functional group include a carboxylic acid group, a sulfonic acid group, an amide group, a phenolic hydroxyl group, a sulfonamide group, a sulfonimide group, and a phosphonic acid group. The acid value of the resin is preferably 50 to 300.

Specific examples of the resin component of the dry ink according to the present invention include polyacrylic acid, polymethacrylic acid,
Polymaleic acid, poly-α-hydroxyacrylic acid, polyitaconic acid, alkali metal salts and / or ammonium salts of these polyelectrolytes, (meth) acrylic acid / (meth) acrylic acid ester copolymers, styrene / maleic anhydride Acid, maleic acid / acrylic acid copolymer,
Acrylic esters such as (meth) acrylic acid / vinyl acetate copolymers, crotonic acid / methacrylic acid ester copolymers, crotonic acid / vinyl acetate copolymers, vinyl benzoate / acrylic acid / methacrylic acid ester copolymers, Examples thereof include copolymers of methacrylic acid ester, vinyl acetate, vinyl benzoate and the like with the above carboxylic acid-containing monomer. Furthermore, a copolymer containing a monomer having the above-mentioned anionic functional group, a rosin-modified maleic acid resin, a rosin-modified phenol resin, a novolac phenol resin, a xylene resin, or the like can be used. These resins may be used alone or in combination of two or more.

In the dry ink according to the present invention, the above resin component is dispersed or dissolved in a suitable solvent to fill the inside of the through hole and then dried at a temperature of 20 to 120 ° C. to remove the solvent.

The ultraviolet light curable ink which can be used in the present invention contains a photopolymerizable oligomer, a photopolymerizable monomer, a photopolymerization initiator, a photopolymerization aid and a polymerization inhibitor, and optionally a defoaming agent, A surfactant such as a leveling agent is added. Examples of the photopolymerizable oligomer that can be used in the present invention include epoxy acrylate, epoxidized oil acrylate, urethane acrylate, unsaturated polyester, polyester acrylate, polyether acrylate,
Examples thereof include acid group, acid anhydride, hydroxy group, glycidyl group-containing acrylate, polyene / thiol, silicon acrylate, polybutadiene acrylate, and polystyrylethyl methacrylate. In addition, "UV / EB curing handbook (raw materials)" (Kiyomi Kato edition, published in 1985, Kobunshi Kogyo Kaisha), "UV curing system" (Kiyomi Kato edition, published in 1989, (stock) ) Photopolymerizable oligomers described in, for example, General Technology Center) can also be used. These oligomers need to contain anionic functional groups because the cured resin must be an alkali-soluble type. The acid value of the photopolymerizable oligomer used in the present invention is preferably 50 to 300.

The photopolymerizable monomer used in the present invention may be one having at least one functional group in the molecule, such as vinyl group, acryloyl group and methacryloyl group, which contributes to the polymerization reaction. Examples of the photopolymerizable monomer used in the present invention include ethanol, propanol, hexanol, octanol, cyclohexanol, glycerin, trimethylolpropane, pentaerythritol, and other alcohols (meth) acrylic acid ester, methylamine, ethylamine, Butylamine, benzylamine, ethylenediamine, hexylenediamine, diethylenetriamine, hexamethylenediamine,
Reaction products of amines such as xylylenediamine, dimethylamine, diethylamine, ethanolamine, diethanolamine and aniline with glycidyl (meth) acrylate and allylglycidyl, acryl such as acrylamide, methacrylamide, N-methylolacrylamide and methylenebisacrylamide. Derivatives, carboxylic acids such as acetic acid, propionic acid, benzoic acid, (meth) acrylic acid, phthalic acid, succinic acid, maleic acid, tartaric acid, and citric acid, and glycidyl (meth) acrylate, allylglycidyl or tetraglycidyl metaxylylenediamine The reaction product with and the like can be mentioned. In addition, the "UV
・ EB curing handbook (raw materials) "(edited by Kato Kiyomi, 1
The photopolymerizable monomers described in "1985, published by Kobunshi Kogyo Kaisha, Ltd." and "Ultraviolet curing system" (edited by Kiyomi Kato, published in 1989, published by Sogo Gijutsu Center) can also be used.

As the photopolymerization initiator that can be used in the present invention, various known polymerization initiators can be used as long as they can absorb the ultraviolet light to polymerize the photopolymerizable oligomer and the photopolymerizable monomer. can do. As the photopolymerization initiator used in the present invention, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 4-t-butyl-trichloroacetophenone, 4-phenoxydichloroacetophenone, 1-
Acetophenone derivatives such as hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin derivatives such as benzyldimethyl ketal, benzophenone, methyl benzoylbenzoate, acrylated benzophenone, acridone, benzophenone derivatives such as 2-chloroacridone, Thioxanthone, 2-chlorothioxanthone, 2,
Thioxanthone derivatives such as 4-diethylthioxanthone, quinone derivatives such as p-benzoquinone, camphorquinone, β-naphthoquinone and 2-ethylanthraquinone,
Peroxides such as benzoyl peroxide and peroxides, sulfur compounds such as dibenzyl sulfide and di-n-butyl disulfide, 2-azobisisobutyronitrile, p-
Examples thereof include azo or diazo compounds such as diazobenzylethylaniline and halogen compounds such as silver bromide and carbon tetrabromide.

As the photopolymerization aid which can be used in the present invention, triethanolamine, methyldiethanolamine, triisopropanolamine, Michler's ketone,
4,4′-diethylaminobenzophenone, ethyl 2-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate and the like can be mentioned.

The ultraviolet light curable ink according to the present invention includes
It is preferable to add a polymerization inhibitor in order to provide storage stability. As the polymerization inhibitor, hydroquinone, p
-Methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4'-thiobis (3-methyl-6-t-butylphenol), 2,2'-methylenebis (4- Methyl-
6-t-butylphenol), 2-mercaptobenzimidazole and the like can be used.

The ultraviolet light curable ink according to the present invention is cured by exposing the filled ink to ultraviolet light.
As the curing device, "Printed Circuit Technology Handbook-Second Edition-" (printed by The Printed Circuit Society of Japan, published in 1993, published by Nikkan Kogyo Shimbun), "UV curing system" (edited by Kiyomi Kato, published in 1989) Published by Sogo Gijutsu Center Co., Ltd.)
The light source or curing device described above can be used. After curing with ultraviolet light, heat treatment may be performed at 40 to 120 ° C. to increase the degree of curing. The curing time of the ultraviolet light curable ink according to the present invention is appropriately set depending on the ink composition, the content of the photopolymerization initiator, the amount of the filled ink 23, the properties of the light source (output, spectrum, etc.), the presence or absence of oxygen, and the temperature. To do.

The thermosetting ink according to the present invention includes:
For example, a mixture of a resin component such as a melamine-modified epoxy resin, a bisphenol type epoxy resin, a novolac type epoxy resin and a tertiary amine as a curing agent, an imidazole derivative, a phenol resin or the like is used. The resin component and the curing agent may be mixed immediately before use, or may be mixed when the ink 23 is manufactured. The resin component preferably contains an anionic functional group and has an acid value of 50 to 50.
300 is good.

The thermosetting ink according to the present invention includes
In the above-mentioned ultraviolet light curable ink, one using a thermal polymerization initiator instead of the photopolymerization initiator can also be used. Examples of the thermal polymerization initiator include azo or diazo compounds such as 2,2′-azobisisobutyronitrile, 1-azobis-1-cyclohexanecarbonitrile, p-diazobenzylethylaniline and Congo red, benzoyl peroxide, Peroxides such as peroxide esters and cumyl hydroperoxide can be used.

The thermosetting ink according to the present invention is heated at a temperature of 30 to 250 ° C. after filling to polymerize the ink components. As the curing device, the devices described in the above-mentioned "Printed Circuit Technology Handbook-Second Edition-" and the like can be used. Curing time, ink composition, thermal polymerization initiator, curing agent content,
Adjust as appropriate in consideration of the presence or absence of oxygen and the influence of temperature.

In the ink layer according to the present invention shown in FIG. 3, the electric conductivity of 10 ^-9 S / cm or more after drying is obtained in any of the dry type, ultraviolet light curing type, and thermosetting type inks. It is necessary to change the content of the polymer, the oligomer, the content of the anionic monomer in the monomer, the substituent of the nonionic monomer and the content thereof, which are the components of the ink layer, to obtain the desired electrical conductivity. Get conductivity. Examples of the substituent of the nonionic monomer include a hydroxy group and a polyoxyethylene group.

In order to adjust the electric conductivity and viscosity, the ink according to the present invention contains conductive titanium oxide, alumina,
Zirconia, antimony oxide, indium tin oxide, carbon black or the like may be added. Further, two or more kinds of these compounds may be mixed.

The ink according to the present invention may be dissolved in a suitable solvent to obtain a desired viscosity. As a solvent,
For example, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone, alcohols such as methanol, ethanol, 2-methoxyethanol, 2-propanol, ethyl acetate, propyl acetate, butyl acetate, n-amyl acetate. , Esters such as methyl formate, ethyl propionate, dimethyl phthalate and ethyl benzoate, aromatic hydrocarbons such as toluene, xylene, benzene, ethylbenzene, carbon tetrachloride, trichloroethylene, chloroform,
1,1,1-trichloroethane, monochlorobenzene,
Halogenated hydrocarbons such as chloronaphthalene, tetrahydrofuran, 1,4-dioxane, dioxolane,
There are ethers such as diethyl ether and ethylene glycol monomethyl ether, dimethylformamide, dimethylsulfoxide, and the like.

A roll coater, a squeegee, a multi-pin method or the like can be used as a method for filling the ink according to the present invention into the through holes and a method for applying the ink on the second metal conductive layer.

In the present invention, even if the ink layer provided on the second metal conductive layer is thin, there is no particular problem, but if it is thick, the progress of elution is hindered and the deterioration of the eluate is promoted. The thickness of the ink layer according to the present invention is 0.1 to
15 μm, more preferably 0.5 to 10 μm. In order to adjust the film thickness within this range, the ink may be removed by a scraping method or the like after coating by the above coating method. In the present invention shown in FIG. 2, the ink layer formed on the second metal conductive layer is removed by a method such as polishing.

The laminated board having the first metal conductive layer provided on the insulating substrate according to the present invention includes a paper base material or a glass base material impregnated with an epoxy resin or a phenol resin, a polyester film, a polyimide film. It is possible to use a substrate obtained by laminating a metal conductive layer of copper, silver, aluminum or the like on an insulating substrate such as. As these laminated plates, those described in "Printed Circuit Technology Handbook-Second Edition-" (edited by The Printed Circuit Society of Japan, published in 1993, published by Nikkan Kogyo Shimbun) can be used.

Various thicknesses can be used as the thickness of the first metal conductive layer according to the present invention, and generally 5 μm to 35 μm.
Although the μm type is used, thicker and thinner ones can also be used. In order to manufacture a printed wiring board having high resolution, the metal conductive layer 12 should have a small thickness.

In the method for manufacturing a printed wiring board of the present invention,
After forming a through hole having a desired diameter in the laminated plate, a metal plating process is performed to form a second metal conductive layer inside the through hole and on the surface of the first metal conductive layer. When the metal is copper, "Surface mounting technology" (June 1993 issue,
The electroless copper plating-electrolytic copper plating step, the direct plating (direct electrolytic copper plating) step, etc. described in Nikkan Kogyo Shimbun can be used.

The photoconductive layer according to the present invention comprises at least a photoconductive compound and a binder resin. As the photoconductive compound used in the present invention, organic and inorganic photoconductive compounds can be used. Examples of the inorganic photoconductive compound include selenium and selenium alloys, amorphous silicon, cadmium sulfide, zinc oxide, zinc sulfide and titanium oxide. As the organic photoconductive compound, a) a triazole derivative described in U.S. Pat. No. 3,121,197, etc., b) an oxadiazole derivative described in U.S. Pat. No. 3,189,447, etc., c) JP-B-37- Imidazole derivatives described in JP-A-16096, etc., d) US Pat. Nos. 3,542,544 and 3,615,402.
No. 3820989, Japanese Patent Publication No. 45-555
No. 51-10983, JP-A-51-93224.
No. 55-108667, No. 55-156953.
And polyarylalkane derivatives described in JP-A-56-36656, e) U.S. Pat. Nos. 3,180,729 and 4,278,746, JP-A-55-88064, and JP-A-55-8806.
5, No. 49-105537, No. 55-51086.
No. 56-80051, No. 56-88141, No. 57-45545, No. 54-112637, No. 55.
-74546 and other pyrazoline derivatives and pyrazolone derivatives, f) US Pat. No. 3,615,404, Japanese Patent Publication No. 51-
10105, 46-3712, 47-2833.
6, JP-A Nos. 54-83435 and 54-11083.
6, phenylenediamine derivatives described in JP-A No. 54-119925, g) U.S. Pat. Nos. 3,567,450 and 3,180,703.
Nos. 3,405,597, 3,658,520 and 42
No. 32103, No. 41755961, No. 4012376
Description, West German Patent (DAS) 1110518, JP-B-49-35702, 39-27577, JP-A-55-144250, 56-119132, 56-22437, etc. Arylamine derivatives, h) amino-substituted chalcone derivatives described in US Pat. No. 3,526,501, i) N, described in US Pat. No. 3,542,546, etc.
N-bicarbazyl derivative, j) oxazole derivative described in U.S. Pat. No. 3,257,203, k) styrylanthracene derivative described in JP-A-56-46234, l) JP-A-54-110837, etc. Fluorenone derivatives described in m. U.S. Pat. No. 3,717,462, JP-A-54-
59143 (corresponding to US Pat. No. 4,150,987),
55-52063, 55-52064, 55
-46760, 55-85495, 57-11.
No. 350, No. 57-148749, No. 57-1041
44, etc., n) US Pat. Nos. 4,047,948 and 4,047,949.
No. 4265990, No. 4273846, No. 42
Benzidine derivatives described in JP-A-99897 and JP-A-4306008, o) JP-A-58-190953 and 59-95540
No. 59-97148, 59-195658,
Stilbene derivatives described in JP-B No. 62-36674 and the like, p) Polyvinylcarbazole and derivatives thereof described in JP-B-34-10966, and q) Polyvinyl compounds described in JP-B-43-18674 and 43-19192. Vinyl polymers such as bilene, polyvinyl anthracene, poly-2-vinyl-4- (4'-dimethylaminophenyl) -5-phenyloxazole, poly-3-vinyl-N-ethylcarbazole, r) JP-B-43-19193 Polymers such as polyacenaphthylene, polyindene, and acenaphthylene / styrene copolymers described in JP-B No. 56-13940.
Condensation resins such as formaldehyde resin and ethylcarbazole / formaldehyde resin, t) JP-A-56-90883 and 56-161550.
Various triphenylmethane polymers described in Japanese Patent Publication No. 387086, u) U.S. Pat.
JP-A-51-90827 and 52-655643.
And metal-free (oxide) phthalocyanines and naphthalocyanines, and their derivatives described in JP-A Nos. 64-2061 and 64-4389. The organic photoconductive compound according to the present invention is not limited to the compounds listed in a) to u), and other organic photoconductive compounds can be used. Two or more kinds of these organic photoconductive compounds can be used in combination, if desired.

Further, in the present invention, various pigments, dyes and the like can be used in combination for the purpose of improving the sensitivity of the photoconductive layer and imparting sensitivity in a desired wavelength range. Examples of these are: 1) U.S. Pat. Nos. 4,436,800 and 4,439,506; JP-A-47-37543 and JP-A-58-1235.
No. 41, No. 58-192042, No. 58-21926
No. 3, No. 59-78356, No. 60-179746.
No. 61-148453, No. 61-238063.
Nos. 60-5941 and 60-45664, etc., monoazo, bisazo, and trisazo pigments, 2) perylene pigments described in U.S. Pat. No. 3,371,884, etc., 3) British Patent No. 2237680. Indigo and thioindigo derivatives described in the specification, 4) quinacridone pigments described in British Patent No. 2237679, etc., 5) British Patent No. 2237678, JP-A No. 59-
No. 184348, No. 62-28738 and the like, 6) Polycyclic quinone pigments, 6) Bisbenzimidazole pigments, such as those described in JP-A-47-30331, and 7) U.S. Pat. Nos. 4,396,610 and 4,644,082. Squalium salt-based pigments described in the specification, etc., 8) JP-A-59-53850 and JP-A-61-212542.
Azurenium salt-based pigments described in Japanese Patent Publication No. In addition, as a sensitization fee, "Electronic photography" 129 (19
73), "Synthetic Organic Chemistry" 24 No. 11 1010
Known compounds described in (1966) and the like can be used. Examples thereof include 9) U.S. Pat. Nos. 3,141,770, 4,283,475, JP-B-48-25658, and JP-A-61-71.
Pyrylium dyes described in 965 JP etc., 10) Applied Optics Supplement 3 50 (196
9), triarylmethane dyes described in JP-A-50-39548, etc., 11) cyanine dyes described in US Pat. No. 3,597,196, etc., 12) JP-A-59-164588, 60. -1630
Nos. 47 and 60-252517, etc., and styryl dyes. These sensitizing dyes may be used alone or in combination of two or more.

In order to improve the sensitivity of the photoconductive layer according to the present invention, in addition to compounds such as trinitrofluorenone, chloranil, tetracyanoethylene, etc., JP-A-58-654.
No. 39, No. 58-102239, No. 58-12943.
The compounds described in No. 9, No. 60-71965, etc. can be used in combination.

The binder resin used in the photoconductive layer according to the present invention must satisfy the electrophotographic characteristics including chargeability and the solubility with an alkali eluate.
Further, it is necessary to have resistance to an etching solution used when removing the first metal conductive layer and the second metal conductive layer. Therefore, a resin having an anionic functional group is particularly used as the binder resin. If the composition ratio of the anionic monomer in the binder resin in the formed photoconductive layer is high, the resin film becomes fragile, and further the ionic conductivity becomes high and the electrophotographic characteristics such as dark electrification are deteriorated. The resin composition of the binder resin used in the invention is appropriately adjusted by copolymerizing an anionic monomer with a nonionic monomer.

Among the resins having an anionic functional group, the monomer-containing copolymer having a carboxylic acid group and the phenol resin have high charge retention and can be advantageously used. The monomer-containing copolymer having a carboxylic acid group, a copolymer of styrene and maleic acid monoester, acrylic acid or methacrylic acid and their alkyl esters,
Binary or higher copolymers with aryl or aralkyl esters are preferred. Further, a copolymer of vinyl acetate and crotonic acid is also preferable. Among the phenolic resins, particularly preferred are phenol, o-cresol, m-cresol,
Alternatively, a novolak resin obtained by condensing p-cresol and formaldehyde or acetaldehyde under acidic conditions can be mentioned.

Specific examples of the binder resin used in the photoconductive layer according to the present invention include styrene / maleic acid monoalkyl ester copolymers, methacrylic acid / methacrylic acid ester copolymers, styrene / methacrylic acid / methacrylic acid esters. Copolymer, acrylic acid / methacrylic acid ester copolymer, methacrylic acid / methacrylic acid ester / acrylic acid ester copolymer, styrene / methacrylic acid / acrylic acid ester copolymer, styrene / acrylic acid / methacrylic acid ester copolymer Styrene, acrylic acid ester, such as coalesce, vinyl acetate / crotonic acid copolymer, vinyl acetate / crotonic acid / methacrylic acid ester copolymer, vinyl benzoate / acrylic acid / methacrylic acid ester copolymer,
Copolymers of methacrylic acid ester, vinyl acetate, vinyl benzoate and the like with the above-mentioned carboxylic acid-containing monomers, and monomers having methacrylic acid amide, phenolic hydroxyl group, sulfonic acid group, sulfonamide group, sulfonimide group, phosphonic acid group Examples thereof include a copolymer containing, a phenol resin, a xylene resin, and the like. These binder resins may be used alone or in combination of two or more. Also,
The weight average molecular weight of the binder resin is preferably 5,000 to 200,000.

It is desirable that the ink layer according to the present invention has higher solubility in the eluate than the photoconductive layer. That is, under the same conditions, the time for the photoconductive layer is 4/5 or less, more preferably 1
It is preferable that the elution is performed at a time of ½ or less.

The mixing ratio of the photoconductive compound to the binder resin in the photoconductive layer according to the present invention depends on the electrophotographic characteristics such as photosensitivity of the photoconductive compound, but the chargeability required for toner development is secured. After setting the binder resin to the minimum film thickness, the mixing ratio with the photoconductive compound is determined so that the desired sensitivity and residual potential are obtained. In the photoconductive layer according to the present invention, the photoconductive compound is preferably in the range of about 1 to 100% by weight, and more preferably 5 to 40% by weight of the amount of the binder resin.

The photoconductive layer according to the present invention is produced by a bar coating method, a roll coating method, a curtain coating method, a spray coating method, a transfer method from a release substrate, a dipping method, an electrodeposition method or the like. The coating liquid is prepared by dissolving and dispersing the components constituting the photoconductive layer in a suitable solvent. It is preferable to use a solvent in which the ink filling the through holes is insoluble or hardly soluble. However, even if the solvent dissolves the ink, the layer structure shown in FIG. 2C can be formed depending on the coating method and the drying conditions.

When a component such as phthalocyanine which is insoluble in a solvent is used as the photoconductive compound, it is dispersed in an average particle size of 0.4 μm or less, more preferably 0.2 μm or less by a disperser. In addition to the photoconductive compound and the binder resin, the coating liquid may include a plasticizer, a surface active agent, a plasticizer, etc. for the purpose of improving the physical properties of the photoconductive layer, the viscosity of the coating liquid, the dispersibility, etc. Additives can be added. The solid content (photoconductive compound and binder resin) concentration of the coating liquid and the solvent used are appropriately selected depending on the coating method and drying conditions.

When the photoconductive layer is thick, not only the deterioration of the alkaline eluate is promoted in the elution and removal of the photoconductive layer in the non-circuit portion, but also the line of the circuit image is thinned by the side etching to obtain an image with good reproducibility. I can't. On the other hand, if it is thin, problems such as being unable to be charged with electric charges necessary for electrophotographic toner development and causing pinholes occur. The thickness of the photoconductive layer according to the present invention is preferably 0.5 to 10 μm, and further 1
-7 μm is preferable.

As the exposure method in the method for producing a printed wiring board of the present invention, reflection image exposure using a xenon lamp, tungsten lamp, fluorescent lamp or the like as a light source, contact exposure through a transparent positive film, laser light, light emitting diode, etc. Scanning exposure by For scanning exposure, He-Ne laser, He-Cd laser, argon ion laser, krypton ion laser, ruby laser, YAG laser, nitrogen laser, dye laser, excimer laser, GaAs / GaAlA.
Scan exposure using a semiconductor laser such as s or InGaAsP, a laser light source such as an alexandrite laser, or a copper vapor laser, or scanning exposure using a light emitting diode or a liquid crystal shutter (line printer type using a light emitting diode array, liquid crystal shutter array, etc. (Including a light source of). Scanning exposure is preferable from the viewpoint of resolution.

The light source used for exposing the photoconductive layer varies depending on the type of photoconductive compound used and the like. For example, a semiconductor laser can be used when χ-type metal-free phthalocyanine is used, and an argon laser can be used when ε-type copper phthalocyanine and an anzanthrone compound having a spectral absorption around 500 nm are used.

Next, the formed electrostatic latent image is developed with toner. As a toner developing method, a dry developing method (cascade developing, magnetic brush developing, powder cloud developing)
Alternatively, a developing method using a wet toner in which toner particles are dispersed in an appropriate insulating liquid can be used. Among them, the liquid developing method can stably make the toner particles smaller than the dry developing method, so that a finer toner layer can be formed. Therefore, the liquid developing method is used in the invention. preferable.

The toner used in the present invention may be a wet type toner used in electrophotographic printing plates.
It must have resist properties for the elution removal of the photoconductive layer of the non-circuit portion and the etching removal of the metal conductive layer in the subsequent step. Therefore, as the resin component,
For example, methacrylic acid, acrylic resin consisting of methacrylic acid ester, vinyl acetate resin, copolymer of vinyl acetate and ethylene or vinyl chloride, vinyl chloride resin, vinylidene chloride resin, vinyl acetal resin such as polyvinyl butyral, polystyrene, Copolymers of styrene with butadiene and methacrylic acid esters, polyethylene, polypropylene and chlorides thereof, polyester resins such as polyethylene terephthalate and polyethylene isophthalate, polyamide resins such as polycapramide and polyhexamethylene adipamide, phenolic resins, xylene. Resin, alkyd resin, vinyl-modified alkyd resin,
It is preferable to contain gelatin, a cellulose ester derivative such as carboxymethyl cellulose, and other waxes and waxes. Further, the toner may contain a dye or a charge control agent as long as it does not adversely affect development or fixing. Furthermore, it is necessary to selectively use positive and negative charges depending on the photoconductive compound used and the charging polarity at the time of charging.

As the toner developing method, a positive developing method is used in which the exposed portion is developed with a toner having a polarity opposite to that of the electrostatic latent image. In this case, by applying a bias voltage, it is possible to form a toner layer with less toner adhesion to the non-circuit portion and high resolution. The formed toner layer is
For example, heat fixing, pressure fixing, solvent fixing and the like can be used for fixing. The toner layer thus formed is used as a resist to remove the non-circuit portion photoconductive layer and the ink layer with an alkali eluent to form a circuit portion resist image composed of the ink layer, the photoconductive layer and the toner layer.

As a method for eluting and removing the photoconductive layer and the ink layer in the portion where the toner layer is not formed, basically, an elution processor for a non-image area elution type printing plate using an elution solution is used. Can be used. The eluent used in the present invention contains a basic compound. Examples of the basic compound include inorganic basic compounds such as alkali metal silicates, alkali metal hydroxides, phosphoric acid and alkali metal carbonates and ammonium salts, ethanolamines, ethylenediamine, propanediamines, triethylenetetramine, morpholine. An organic basic compound or the like can be used. The above basic compounds can be used alone or as a mixture. Water can be advantageously used as a solvent for the eluate.

In order to remove the second metal conductive layer and the first metal conductive layer exposed by the elution of the photoconductive layer and the ink layer,
The etching device described in the above-mentioned "Printed Circuit Technology Handbook-Second Edition-" (edited by Japan Printed Circuit Industry Association, published in 1993, published by Nikkan Kogyo Shimbun) can be used. When the first metal conductive layer and the second metal conductive layer are formed of copper, ferric chloride solution, cupric chloride solution, or the like can be used.

After the metal wiring pattern corresponding to the circuit portion is formed by etching, the metal wiring pattern has a photoconductive layer and a toner layer which are resist images, and the ink layer is also formed by the method shown in FIG. It remains. Ink is filled in the through hole. These may exist as they are, but are often unnecessary when connecting circuit components, chips, and the like. At this time,
These can be removed by treating with a solution having a higher alkalinity than the alkali eluent, as in the case of manufacturing a printed wiring board using a general photosensitive polymer. For this, an organic solvent such as methyl ethyl ketone, methanol, ethanol, butanol, dioxane can be mixed with the alkaline solution, and in some cases only the organic solvent is used.

[0055]

Embodiments of the present invention will be described more specifically with reference to FIGS. The present invention is not limited to the following examples as long as the gist thereof is not exceeded.

Example 1 Preparation of Through Hole 1 and Ink 23 Filled Paper Base Material Phenolic Resin Plate 11 Copper foil laminated on both sides of copper foil 12 (Matsushita Denko KK, 200 × 250)
X 1.6 mm, copper thickness 18 μm), 0.4 mmφ and 0.
After opening 50 through holes each of 6 mmφ, copper plating treatment (OPC process M: Okuno Chemical Industries Co., Ltd.) was performed.
A copper layer 13 having a thickness of 8 μm was provided inside the through hole 1 and on the surface of the copper foil 12. Next, the ink 23 having the composition shown in Table 1 was applied by a roll coating method, dried at 80 ° C. for 15 minutes, and then the ink layer attached to the copper layer 13 was removed by buffing. At this time, the ink 23 was filled in the through hole 1.

[0057]

[Table 1]

Preparation of photoconductive layer 21 After filling the through hole 1 with the ink 23, the ink 23
A photoconductive layer 21 was formed on the coating layer and the copper layer 13 by a spray coating method using a coating liquid having the composition shown in Table 2. 9
When dried with hot air at 0 ° C. for 15 minutes, the film thickness of the photoconductive layer was 5.6 μm on average. Next, the electrostatic characteristics were measured with an electrostatic field measuring instrument SP-428 manufactured by Kawaguchi Electric Co., Ltd. -6.0
When a corona voltage of kV was applied, the initial potential V ₀ (surface potential at the time of charging) −280 V, the charge retention rate CR (1 in the dark)
Surface potential retention rate for 0 seconds) is 97.9%, sensitivity E
_1/2 (exposure amount until the surface potential becomes half after applying ₂ lx of tungsten light) 2.90 lx · sec. ,
The residual potential V _r (surface potential after 7 seconds of exposure) was −7.5 V, which indicates good electrostatic characteristics.

[0059]

[Table 2]

Formation of Toner Layer 22 The surface of the photoconductive layer 21 is -2 by a contact charging method in the dark.
After charging to 50V, semiconductor laser (wavelength 780n
Line width of about 40μ with a flatbed printer using m)
The non-circuit part of m was exposed to obtain an electrostatic latent image. After that, as the liquid toner, positively charged toner (manufactured by Mitsubishi Paper Mills,
A positive development method was performed using "LOM-ED _III " under the application of a bias voltage of +120 V, and then dried at 70 ° C. for 5 minutes to form a toner layer 22. Obtained toner layer 2
No. 2 had a line width of 40 ± 3 μm and a thickness of about 2 μm, and no missing image was confirmed on the way. Further, no defects such as pinholes were found in the toner layer 22 on the through holes.

Alkali elution and metal conductive layers 12, 13
After the above toner layer 22 is formed, it is heated to 35 ° C.
% Sodium carbonate solution, spray pressure 2.0 kg / c
After spraying m ² for 40 seconds, it was washed with tap water to elute and remove the photoconductive layer 21 and the ink 23 layer in the portion not covered with the toner layer 22. Next, spray ferric chloride solution heated to 45 ° C for 60 seconds (spray pressure 3.0 k
g / cm ² ) and the exposed copper layer 13 and copper foil 12 were removed. Furthermore, spray 5.0% sodium hydroxide solution heated to 30 ° C for 5 minutes (spray pressure 2.0 kg
/ Cm ² ) and the photoconductive layer 21, the toner layer 22 and the ink 23 used as the etching resist were removed. Although the obtained metal wiring pattern (line width: 40 μm) had side etching of about 4 μm, a pinhole in the middle,
No defects such as disconnection were confirmed. Further, when the cross section of the through hole 1 was observed with a microscope, the copper on the inner wall was completely protected.

Comparative Example 1 Production of Through Holes and Production of Photoconductive Layer In the same manner as in Example 1, a double-sided copper clad laminate was 0.4 mm thick.
After forming through holes of φ and 0.6 mmφ and performing a copper plating treatment to form a copper layer, the copper layer is immersed in a coating solution having the composition shown in Table 3, dried with hot air at 90 ° C. for 20 minutes, and exposed to light. A conductive layer was produced. The obtained photoconductive layer had good adhesion to the copper layer and had a film thickness of 5.5 ± 3.5 μm. . The electrostatic properties of this photoconductive layer were V ₀ -280 V, CR 97.0%, and E _1/2 under a corona voltage of -6.0 kV.
12 lx · sec. , V _r −10V, which was good. When observed with a microscope, the photoconductive layer adhered to the 0.6 mmφ through hole, but a 0.4 mm
In the φ through hole, a band-shaped coating failure portion was observed at the center of the hole.

[0063]

[Table 3]

Preparation of Toner Layer The surface of the laminated plate having the photoconductive layer formed thereon was charged, exposed and toner-developed in the same manner as in Example 1 to prepare a toner layer corresponding to the circuit section. The resulting toner layer has a line width of 40
The thickness was ± 3 μm and the thickness was about 2 μm. When observing the inside of the through hole with a microscope, it was found that the toner was evenly attached to the inner wall of the 0.6 mmφ through hole.
In the mφ through hole, no toner adhesion was confirmed to the portion where the photoconductive layer was not manufactured.

Elution of alkali and etching of metal conductive layer
The laminated plate having the toner layer formed thereon was treated in the same manner as in Example 1 to remove the photoconductive layer and the copper layer other than the circuit portion. Further, spray 3.0% sodium hydroxide solution heated to 30 ° C. for 3 minutes (spray pressure 2.0 kg / c
m ² ) and the photoconductive layer and the toner layer used as the resist were removed. Obtained metal wiring pattern (line width 40μ
No defect was confirmed in m) except that there was side etching of about 3 μm. When the cross section of the through hole was observed with a microscope, the copper in the through hole where the toner layer was not formed was etched (0.6
mmφ; 0 pieces, 0.4 mmφ; 21 pieces).

Example 2 Preparation of Through Hole 1, Filling of Ink 23 and Ink
Preparation of Layer 24 Through holes 1 were formed in the copper clad laminate by the same method as in Example 1, and after copper plating treatment was performed, it was applied by roll coating using an ink having the composition shown in Table 4. ,
It was dried with hot air at 70 ° C. for 20 minutes. Ink layer 24 after drying
Has a thickness of 1.5 μm and an electric conductivity of 1 × 10 ⁻⁶
It was S / cm. The ink 23 was also filled inside the through hole 1.

[0067]

[Table 4]

Preparation of Photoconductive Layer 21 The photoconductive layer 21 was formed on the through hole 1 filled with the ink 23 and the surface of the ink layer 24 by a roll coating method using a coating liquid having the composition shown in Table 2. 15 at 90 ° C
When dried with hot air for a minute, the film thickness of the photoconductive layer 21 was 5.0 μm on average. Next, the electrostatic characteristics were measured with an electrostatic field measuring instrument SP-428 manufactured by Kawaguchi Electric Co., Ltd. When a corona voltage of -6.0 kV was applied, V ₀ -280 V, CR
97.8%, E _1/2 2.90 lx · sec. , V _r
It showed a good electrostatic characteristic of -8.0V.

Formation of Toner Layer 22 The photoconductive layer 21 is -280 in the dark by a contact charging method.
After being charged to V, the circuit portion having a line width of about 40 μm was exposed by a flat bed printer using a semiconductor laser (wavelength 780 nm) to obtain an electrostatic latent image. After that, a positive development method was performed in the same manner as in Example 1, and then dried at 70 ° C. for 5 minutes to form a toner layer 22. The toner layer 22 thus obtained had a line width of 40 ± 2.5 μm and a thickness of about 2 μm, and no missing image was confirmed during the process. Further, no defects such as pinholes were found in the toner layer 22 in the through hole 1 portion.

Alkali elution and metal conductive layers 12, 13
After the toner layer 22 is formed, the same treatment as in Example 1 is performed to remove the photoconductive layer 21, the ink layer 24, the copper layer 13 and the copper foil 12 in the portions not covered with the toner layer 22. Then, the remaining toner layer 22, photoconductive layer 21, ink layer 24 and ink 23 were peeled off. The obtained metal wiring pattern (line width 40 μm) had side etching of about 3 μm, but no defects such as pinholes and disconnections were confirmed. Further, when the cross section of the through hole 1 was observed with a microscope, the copper on the inner wall was completely protected.

Example 3 Preparation of Through Hole 1 and Filling with Ink 23 In the same manner as in Example 1, the through hole 1 was opened in the double-sided copper-clad laminate, a copper plating treatment was performed, and a copper layer 13 was provided. An ultraviolet light curable ink having the composition shown in FIG. 5 is applied to the surface of the copper layer 13 by a roll coating method and filled in the through hole 1, and ultraviolet light (high pressure mercury lamp 100 W / cm; Sen special light source) at 40 ° C. (Manufactured by KK) was applied for 10 minutes to cure the filled ink 23 and the ink layer 24. After that, in order to remove the ink layer 24 attached to the surface of the copper layer 13, buffing and washing with water were performed. The electric conductivity of the ink 23 after curing was 4 × 10 ⁻⁶ S / cm.

[0072]

[Table 5]

Preparation of Photoconductive Layer 21 The photoconductive layer 21 was formed on the through holes 1 filled with the ink 23 and on the surface of the ink layer 24 by the roll coating method using the coating liquid having the composition shown in Table 2. 15 at 90 ° C
When dried with hot air for a minute, the film thickness of the photoconductive layer 21 was 5.0 μm on average. Next, the electrostatic characteristics were measured with an electrostatic field measuring instrument SP-428 manufactured by Kawaguchi Electric Co., Ltd. When a corona voltage of -6.0 kV was applied, V ₀ -280 V, CR
97.8%, E _1/2 2.90 lx · sec. , V _r
It showed a good electrostatic characteristic of -8.0V.

Formation of Toner Layer 22 The photoconductive layer 21 is -280 in the dark by a contact charging method.
After being charged to V, the circuit portion having a line width of about 40 μm was exposed by a flat bed printer using a semiconductor laser (wavelength 780 nm) to obtain an electrostatic latent image. After that, a positive development method was performed in the same manner as in Example 1, and then dried at 70 ° C. for 5 minutes to form a toner layer 22. The toner layer 22 thus obtained had a line width of 40 ± 2.5 μm and a thickness of about 2 μm, and no missing image was confirmed during the process. Further, no defects such as pinholes were found in the toner layer 22 in the through hole 1 portion.

Alkali elution and metal conductive layers 12, 13
After the above toner layer 22 is formed, the same treatment as in Example 1 is carried out to remove the photoconductive layer 21, the copper layer 13 and the copper foil 12 in the portions not covered with the toner layer 22, and further leave them. Then, the toner layer 22, the photoconductive layer 21, and the ink 23 were removed. Obtained metal wiring pattern (line width 40 μm)
Although there was a side etching of about 3 μm, defects such as pinholes and disconnections were not confirmed. Also, when observing the cross section of the through hole 1 with a microscope,
The copper on the inner wall was completely protected.

Example 4 Preparation of Through Hole 1 and Filling with Ink 23 In the same manner as in Example 1, the through hole 1 was opened in the copper clad laminate and subjected to metal plating treatment, and then the composition shown in Table 6 was obtained. The ink was applied by the roll coating method and dried with hot air at 80 ° C. for 20 minutes to cure the ink 23. The ink adhering to the copper layer 13 was removed by buffing and washing with water.

[0077]

[Table 6]

Preparation of Photoconductive Layer 21 On Through Hole 1 Filled with Ink 23 and Copper Layer 13
A photoconductive layer 21 was formed on the surface of the above by a roll coating method using the coating liquid having the composition shown in Table 2. When dried with hot air at 90 ° C. for 15 minutes, the film thickness of the photoconductive layer 21 was 5.
It was 0 μm. Next, the electrostatic field measuring instrument S made by Kawaguchi Electric Co., Ltd.
The electrostatic characteristics were measured with P-428. When a corona voltage of -6.0 kV was applied, V ₀ -280 V, CR 9
7.8%, E _1/2 2.90 lx · sec. , V _r −
It showed a good electrostatic property of 8.0V.

Formation of Toner Layer 22 The photoconductive layer 21 is -280 in the dark by a contact charging method.
After being charged to V, the circuit portion having a line width of about 40 μm was exposed by a flat bed printer using a semiconductor laser (wavelength 780 nm) to obtain an electrostatic latent image. After that, a positive development method was performed in the same manner as in Example 1, and then dried at 70 ° C. for 5 minutes to form a toner layer 22. The toner layer 22 thus obtained had a line width of 40 ± 2.5 μm and a thickness of about 2 μm, and no missing image was confirmed during the process. Further, no defects such as pinholes were found in the toner layer 22 in the through hole 1 portion.

Alkali elution and metal conductive layers 12, 13
After the above toner layer 22 is formed, the same treatment as in Example 1 is carried out to remove the photoconductive layer 21, the copper layer 13 and the copper foil 12 in the portions not covered with the toner layer 22, and further leave them. Then, the toner layer 22, the photoconductive layer 21, and the ink 23 were removed. Obtained metal wiring pattern (line width 40 μm)
Although there was a side etching of about 3 μm, defects such as pinholes and disconnections were not confirmed. Also, when observing the cross section of the through hole 1 with a microscope,
The copper on the inner wall was completely protected.

[0082]

As described above, according to the method for manufacturing a printed wiring board of the present invention, a resist image having a high resolution can be obtained by using an electrophotographic photosensitive member as a resist material, and the through hole 1 can be protected. By using the alkali-soluble ink 23, the second metal conductive layer 13 in the through hole 1 portion can be easily protected, and a high-density printed wiring board can be manufactured.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing a method for manufacturing a printed wiring board using a conventional electrophotographic method.

FIG. 2 is a schematic explanatory view showing a method for manufacturing a printed wiring board of the present invention.

FIG. 3 is a schematic explanatory view showing another method for manufacturing a printed wiring board of the present invention.

[Explanation of symbols]

 1 Through Hole 11 Insulating Substrate 12 First Metal Conductive Layer 13 Second Metal Conductive Layer (Plating Layer) 21 Photoconductive Layer 22 Toner Layer 23 Ink 24 Ink Layer

Claims (2)

[Claims] 1. A through hole is formed in a laminated plate having a first metal conductive layer on both sides of an insulating substrate, and a metal plating treatment is performed to provide a second metal conductive layer inside the through hole and on the surface of the laminated plate. After that, a photoconductive layer is formed on the second metal conductive layer, then a toner layer corresponding to the circuit portion is formed by electrophotographic positive development, and the photoconductive layer other than the toner layer portion is eluted and removed. After forming an etching resist including a toner layer and a photoconductive layer, the exposed second metal conductive layer and the first metal conductive layer are formed.
In the method for manufacturing a printed wiring board, wherein the metal conductive layer is removed by etching, and the remaining etching resist is removed according to circumstances, at least the inside of the through hole is filled with an alkali-soluble ink before providing the photoconductive layer. A method for manufacturing a printed wiring board, comprising: 2. A through hole is opened in a laminate having a first metal conductive layer provided on both sides of an insulating substrate, and a metal plating process is performed to provide a second metal conductive layer inside the through hole and on the surface of the laminate. After that, the inside of the through hole is filled with ink, and the photoconductive layer is formed on the ink layer formed on the second metal conductive layer, and then the toner layer corresponding to the circuit portion is formed by the electrophotographic positive development method. After forming, the photoconductive layer other than the toner layer portion is eluted and removed to form an etching resist composed of the toner layer and the photoconductive layer, and then the exposed second metal conductive layer and first metal conductive layer are removed by etching. And a method for manufacturing a printed wiring board, wherein the remaining etching resist is removed depending on the case.
^-9 . A method for producing a printed wiring board, which has an electric conductivity of ^-9 S / cm or more and has a higher solubility in an eluate than a photoconductive layer.