JPS6213835B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a multilayer printed wiring board.

Printed wiring is usually done by drilling holes such as jig holes or through holes in an insulating synthetic resin laminate made of phenolic resin, polyester resin, epoxy resin, or tetrafluoroethylene resin, and then using the synthetic resin laminate with copper. By bonding the copper foil with the foil and then etching the bonded copper foil, or by bonding the copper foil to the support made of the insulating resin via an adhesive layer, a copper foil bonded laminate is produced. , by drilling holes such as jig holes or through holes, and then etching the negative wiring part on the copper foil surface to obtain a positive wiring pattern using copper foil, or by electrodepositing metal onto a synthetic resin laminate. It is created by forming a wiring pattern.

However, in the conventional method described above,
It takes time and effort to punch or drill holes such as jig holes and through holes in the synthetic resin laminate using a punching die, and it is necessary to bond the synthetic resin laminate and the copper foil with adhesive. However, its manufacture was not easy.

The present inventor has conducted research into a method for eliminating the manufacturing complexity by omitting the punching or drilling process of synthetic resin laminates and the bonding process between synthetic resin laminates and copper foil in the conventional manufacturing of printed wiring boards. As a result, we have completed the present invention.

That is, the gist of the present invention is to form an nth partial laminated wiring made of a metal film on the surface of a substrate for manufacturing a multilayer printed wiring board by a printing method or an electroforming method, and to a step of forming an nth partial insulating layer made of an electrically insulating resin film by an image forming method such as a printing method or a resist plate making method to cover a part of the laminated wiring; Formation of first partial laminated wirings, n-1, n-2, etc. made of metal films on partial insulating layers of
-1, n-2, . . . forming a first partial insulating layer alternately, and then forming a first partial insulating layer on the substrate for producing a multilayer printed wiring board by a printing method or an electroforming method. A step of forming wiring, and an image using a printing method, a resist engraving method, etc. on the substrate for manufacturing a multilayer printed wiring board on which the n partial laminated wirings, the n partial insulating layers, and the main wiring are formed. A step of forming an electrically insulating support having jig holes, through holes, etc. opened depending on the formation method, and then forming the electrically insulating support, the main wiring,
A method for manufacturing a multilayer printed wiring board, comprising the step of peeling off an integrated body of a partial insulating layer and a partially laminated wiring from the multilayer printed wiring board manufacturing substrate.

According to the manufacturing method of the present invention, a multilayer printed wiring board can be easily obtained without requiring the steps of punching and drilling the support and the step of bonding between the support and the copper foil.

The present invention will be explained in detail below with reference to the drawings.

Negatives of a partially laminated wiring pattern consisting of an electrically insulating material film (resist film) are formed on a conductive substrate such as a mirror-finished stainless steel plate by a conventionally known method such as photoresist engraving, screen printing, or offset printing. Partially laminated wiring made of SnO ₂ , In ₂ O ₃ and metal films such as gold, nickel, copper, zinc, chromium, etc. by forming an image or by vacuum evaporation, spraying, or printing on a glass substrate or ceramic substrate. Form a positive image of the pattern, or use glass substrate, ceramic substrate, steatite substrate, alumina substrate, epoxy resin,
VL-type, VH-type, VA-type (all manufactured by Tamura Seisakusho), paste silver 67, paste on plastic substrates such as phenolic resin, acrylic resin, fluorinated resin, polyethylene resin, vinyl chloride resin, polyvinyl alcohol resin, etc. Silver S-61
(Both manufactured by Nihon Kinryo Co., Ltd.), conductive paste #5900
(manufactured by Electro Science Laboratories Inc.), conductive copper paste (manufactured by Mitsui Toatsu Chemical Co., Ltd.) and other conductive inks are used to create multilayer printed wiring that has a conductive pattern in the form of a partially laminated wiring pattern made of a metal film. Fabricate a substrate for board production.

FIG. 1 shows a multilayer printed wiring board manufacturing substrate 5 manufactured by the first method described above.

A resist image 2 showing a negative image of the partially laminated wiring pattern on the conductive metal plate 1 is formed, and the partially laminated wiring pattern is formed by the surface of the conductive metal plate 1 exposed through the opening 3 of the resist image 2. A shaped conductive pattern 4 is formed.

FIG. 2 shows a multilayer printed wiring board manufacturing substrate 8 produced by the second and third methods described above, in which a conductive metal film image 7 showing a positive image of a partially laminated wiring pattern is formed on an electrically insulating board 6. It is provided.

A peeling film (not shown) is formed on the substrate 5 for producing a multilayer printed wiring board shown in the first figure or the substrate 8 for producing a multilayer printed wiring board shown in the second figure according to a known chemical treatment method. 3. After depositing a metal 9 on the area of the conductive pattern 4 by electrodeposition as shown in FIG. As shown in the figure, metal 9 is deposited on conductive metal film image 7 by electrodeposition to form partially laminated wiring 10.

Next, as shown in FIGS. 6a and 6b, a partial insulating layer 11 made of an electrically insulating resin film is formed covering a part of the partially laminated wiring by an image forming method such as a printing method or a resist manufacturing method.

Thereafter, the main wiring 1 is printed on the multilayer printed wiring board 5 or 8 as shown in FIGS. 7a and 7b.
form 2.

Next, a partial insulation layer 11 and a partial laminated wiring 1
Jig holes 13 , through holes 14 , etc. as shown in FIG. An electrically insulating support 15 having openings is formed. Thereafter, the electrically insulating support 15, the main wiring 12, the partial insulating layer 11, and the partially laminated wiring 10 formed as described above are applied.
The integrated product is peeled off from the substrate 5 or 8 to obtain a printed wiring 16 as shown in FIGS. 9a and 9b.

In the above-described method of the present invention, when the partial insulating layer 11 is formed by a printing method, it is desirable to employ a screen printing method, a gravure printing method, or the like as the printing method.

In addition, as ink used for printing, solder resist S-20, S-22, S-30, S-40, S-
50, S-222, S-302, S-402 (manufactured by Taiyo Ink Manufacturing Co., Ltd.), #240-SB (manufactured by Electroscience Laboratories Inc.), Alzerite solder ink (manufactured by Tamura Kaken), solder resist (Fuji Pharmaceutical Co., Ltd.) can be used.

Further, in the method of the present invention described above, the support 15
When forming by a printing method, it is desirable to employ a screen printing method, a gravure printing method, etc. as the printing method.

In addition, the inks used for printing are mainly based on epoxy resins, acrylic resins, phenolic resins, vinyl chloride resins, fluorine resins, imide resins, amide resins, gelatin, casein, etc. Composite inks with organic and inorganic reinforcing substances may be used. Further, after printing, it is necessary to perform ultraviolet curing or heat treatment to form a film.

In addition, when forming the partial insulating layer 11 and the support 15 by photoresist plate making, all commercially available photoresists can be used, such as KMER (manufactured by KODAK), G-
90, OMR (manufactured by Tokyo Ohka), FSR, FR-14,
FR-15 (manufactured by Fuji Pharmaceutical Co., Ltd.) can be used alone or in a composite form by adding an organic or inorganic reinforcing substance to it.

Furthermore, in the method of the present invention described above, the main wiring 12
When forming by a printing method, printing methods include silk screen method, transfer method, gravure method, gravure offset method, offset method, or direct drawing method involves drawing the wiring diagram while extruding ink from a hollow pen. It is preferable to use the following inks, and the inks used for printing include VL-type, VH-type, VA-type (manufactured by Tamura Seisakusho), Paste Silver 67, Paste Silver S61 (manufactured by Nippon Kin Liquid Co., Ltd.), and conductive ink. Conductive inks such as paste #5900 (manufactured by Electro Science Laboratories Inc.) and conductive copper paste (manufactured by Mitsui Toatsu Chemical) can be used.

In the method of the present invention described above, the partially laminated wiring may be formed by a printing method using a conductive paste instead of by the electroforming method.

Furthermore, in the method of the present invention described above, the main wiring may be formed by electroforming instead of by printing.

In addition, partially laminated wiring, partial insulating layer, main wiring,
When the main wiring is formed by a printing method, baking or drying processing is required after printing, but this process is a method in which all the wiring is sequentially printed one on top of the other, and then baking or drying is performed at once. Any method may be used, including printing one layer, baking it, printing a second layer thereon, and then baking it.

Furthermore, in the method of the present invention described above, the main wiring may be formed on the resist 2 without removing it.

The above explanation has been about two-layer laminated wiring, but when three or more layers of conductor crossover are required, in other words, the first, second, ... nth partial laminated wiring and the first, second, etc. 2. When manufacturing a multilayer printed wiring board formed by alternately laminating second partial insulating layers, the nth partial lamination is applied to the surface of the substrate for manufacturing a multilayer printed wiring board as described above. A wiring is formed, a part of this nth partially laminated wiring is covered with an nth partial insulating layer as described above, and the n-1st, n-2nd, . . . The first partially laminated wiring and the n-1st, n-2nd...first partial insulating layers are alternately layered, and then the main wiring is formed on the substrate as described above. , an electrically insulating support having jig holes, through holes, etc., was formed on the substrate on which the n partially laminated wirings, the n partial insulating layers, and the main wiring were formed. Thereafter, a multilayer printed wiring board can be obtained by peeling off the electrically insulating support, main wiring, partial insulating layer, and partially laminated wiring from the substrate.

Next, the present invention will be described in detail with reference to Examples.

Example 1 A 1.0 mm thick stainless steel SUS-304 plate with a mirror finish was prepared and immersed in the tri-clean solution at 20 to 25°C for 3 minutes while stirring, cleaned, and then pulled out. After drying, degrease and wash with 10% Nitsusan Mekretsu (manufactured by Nippon Oil & Fats Co., Ltd.). Photoresist on this one-sided surface; FR
-14 (manufactured by Fuji Pharmaceutical Co., Ltd.) is applied uniformly to a thickness of 0.004 to 0.007 mm, air-dried, and then heat-treated at a temperature of 150 to 170°C for 10 minutes. On the stainless steel (SUS-304) plate coated with this FR-14,
The positive pattern of the partially laminated wiring is closely exposed to light using a xenon lamp and developed with water (6 ortx on the photosensitive surface) to first form a negative pattern of the partially laminated wiring using FR-14. The back side of stainless steel (SUS-304) was protected against corrosion with Sierra varnish, and then copper plated in sulfuric acid copper sulfate plating solution (CuSO ₄ 2.5g/, H ₂ SO ₄ 250g/) to a thickness of 0.030mm. A partially laminated wiring consisting of an electrodeposited copper film is obtained. Leaving both ends of this partially laminated wiring, an electrically insulating solder resist S-20 (manufactured by Taiyo Ink Mfg. Co., Ltd.) was printed on the central part by screen printing at 70 to 80°C.
Dry for 15 minutes at a temperature of 100 to form a partial insulation layer. Next, the main wiring was connected to a conductive copper paste 307 (Mitsui Toatsu Chemical Co., Ltd.) on a stainless steel (SUS-304) substrate with partially laminated wiring and a partial insulating layer.
0.020± by screen printing method using
10 at a temperature of 180-200℃ after printing to a thickness of 0.004mm
Formed by heat treatment for minutes. Next, the insulating vinyl chloride ink with the composition shown below was printed using the screen printing method. A support body having necessary holes such as a device hole and a device hole and having a necessary outer peripheral shape was formed.

[Composition of insulating vinyl chloride ink]

Zeon 2 30g DOP 15g Ferro stabilizer 25g Pigment 10g Xylene 10g Next, the support formed as above, the main wiring,
The partial insulating layer and the partially laminated wiring were peeled off from the stainless steel (SUS-304) substrate to obtain a printed wiring board containing two layers of crossbar wiring.

Example 2 A 2.0 mm thick glass plate having a transparent conductive film mainly composed of indium oxide (resistance value 40 to 80 Ω/cm) was placed on one side, and while stirring the trichlene solution, 20 to 25% of the glass plate was placed in the trichlene solution. ℃ for 3 minutes, then removed, dried, degreased with 10% Nippon Oil & Fats Co., Ltd., and washed with water.The side of the glass plate with the transparent conductive film was FR-14 (manufactured by Fuji Pharmaceutical Co., Ltd.) is applied uniformly to a thickness of 0.004 to 0.007 mm, air-dried, and then heat-treated for 10 minutes at a temperature of 150 to 170°C. A negative pattern of partially laminated wiring is closely attached to a glass substrate, exposed to light using a xenon lamp (60,000 lux on the exposed surface), and developed with water to first form a positive pattern of partially laminated wiring using FR-14.After that, Fecl ₃ is applied. (30
40Be', 60 to 70°C) is used to form a conductive pattern in the form of partially laminated wiring by etching the unnecessary portions using an etching solution. Then, conductivity was established at the edge of the transparent conductive film with silver paste (VL-20, manufactured by Tamura Kaken), and a sulfuric acid copper sulfate plating solution was applied.
Copper plating is performed in CCuSO ₄ 2.5 g/, H ₂ SO ₄ 250 g/) to obtain a partially laminated wiring made of a copper electrodeposition film with a thickness of 0.030 mm.

Leaving both ends of this partially laminated wiring, an electrically insulating solder resist S-20 (manufactured by Taiyo Ink Mfg. Co., Ltd.) was printed on the center part using a screen printing method, and then printed at a temperature of 70 to 80°C. Dry for 15 minutes to form a partial insulation layer. Next, the main wiring is placed on a stainless steel (SUS-304) board with partially laminated wiring and a partial insulation layer with conductive copper paste.
307 (manufactured by Mitsui Toatsu Chemical Co., Ltd.) by screen printing to a thickness of 0.020 ± 0.004 mm, then 180
- Formed by heat treatment at 200℃ for 10 minutes. Next, print using the screen printing method using insulating vinyl chloride ink with the following composition, and after printing
Heat treated for 10 minutes at a temperature of 160-190℃
A support body was formed that had necessary holes such as through holes of 0.20±0.030, jig holes, device holes, etc., and also had a necessary outer peripheral shape.

[Composition of insulating vinyl chloride ink]

Zeon 121 30g DOP 15g Ferro stabilizer 25g Pigment 10g Xylene 10g Next, the support formed as above, the main wiring,
The partial insulating layer and the partially laminated wiring were peeled off from the glass substrate to obtain a printed wiring branch including two layers of crossbar wiring.

As detailed above, according to the manufacturing method according to the present invention, a multilayer printed wiring board can be easily obtained without requiring the punching and trilling process of the support and the process of bonding between the support and copper foil. .

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a substrate for manufacturing a multilayer printed wiring board in which a resist image is provided on a conductive metal plate.
FIG. 2 is a cross-sectional view of a board for manufacturing multilayer printed wiring branches in which a conductive metal film image is provided on a glass substrate.
Figure 3 is a cross-sectional view of the state in which metal has been deposited by electrodeposition on the substrate shown in Figure 1, Figure 4 is a cross-sectional view of the state after the resist has been removed, and Figure 5 is a cross-sectional view of the state in which metal has been deposited on the substrate shown in Figure 2. 6a and 6b are cross-sectional views of a state in which metal has been deposited by electrodeposition, FIGS.
Figures a and b are cross-sectional views with main wiring formed thereon, Figures 8 a and b are cross-sectional views with a support further formed, and Figures 9 a and b are completed multilayer printed wiring boards. FIG. Explanation of the symbols representing the main parts of the figure 1 , 5 ...
Multilayer printed wiring branch manufacturing board, 10... partial laminated wiring, 11... partial insulating layer, 12... main wiring, 1
5...Support, 16 ...Multilayer printed wiring branch.

Claims (1)

[Claims] 1. A step of forming an n-th partially laminated wiring made of a metal film on the surface of a substrate for manufacturing a multilayer printed wiring board by a printing method or an electroforming method, and covering a part of the n-th partially laminated wiring. Then,
a step of forming an nth partial insulating layer made of an electrically insulating resin film by an image forming method such as a printing method or a resist plate making method;
n-1st, n-2nd, made of a metal film on the partial insulating layer of... Formation of the first partially laminated wiring, and n-1st, n-2nd, made of an electrically insulating resin film. ……
...a step of alternately forming a first partial insulating layer; then, a step of forming a main wiring on the substrate for manufacturing a multilayer printed wiring board by a printing method or an electroforming method; A jig hole and a through hole are formed on the multilayer printed wiring board manufacturing substrate on which the partially laminated wiring, the n partial insulating layers, and the main wiring are formed by an image forming method such as a printing method or a resist plate making method. forming an electrically insulating support having openings, etc., and then converting the electrically insulating support, main wiring, partial insulating layer, and partially laminated wiring into the substrate for manufacturing a multilayer printed wiring board. A method for manufacturing a multilayer printed wiring board, comprising a step of peeling it off from the substrate.