JPS6247187A - Manufacture of printed wiring board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing flexible printed wiring boards.

(Prior art) Current flexible printed wiring boards use a thin plastic film as an insulating sheet, bond copper foil to both sides of this insulating sheet with adhesive, and then bond the copper foil. After clearing the hole, apply a plating catalyst to the inner wall of the hole.
4. Form a plating layer on the inner wall of the hole for electroless plating or electroless plating and electroplating, and then etch the copper foil to form a circuit. Manufactured.

(Problems to be Solved by the Invention) However, in the conventional method, it is necessary to apply a plating catalyst to form a layer on the inner wall of the hole, and
Since the process is separate from the circuit formation on the surface, the manufacturing process is complicated and the reliability tends to be similar.

The present invention provides a printed wiring board with a simple manufacturing process and high reliability! ! l The purpose is to obtain Xa6 method 1 constant +lt.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an insulating substrate with no ``y1w''! A method for manufacturing a wiring board for a print 1 on which a circuit can be formed by plating includes a step of impregnating and applying a plating catalyst-containing adhesive to a thin material made of insulating navy blue to form an insulating sheet 1; Provides a method for manufacturing a wiring board, characterized by a step of forming holes in the process of forming a sheet, and forming a plating layer simultaneously on the surface of the insulating sheet and the holes by electroless plating after the step. It is.

(Function) According to the present invention, since the insulating sheet contains a plating catalyst, a plating layer can be simultaneously formed on the sheet surface and the inner wall of the hole by electroless plating, which simplifies the process.

(Example> Embodiments of the present invention will be described below based on the drawings.

First, as shown in FIG. 1, an insulating sheet 2 is prepared by impregnating and coating an adhesive 1 containing a plating catalyst onto a thin material made of an insulating material 1 such as glass, polyester, nylon, or cellulose. The plating catalyst-containing adhesive 1 is one in which a plating catalyst such as a palladium compound is mixed into an acrylonitrile, butadiene rubber, or phenol resin composition.

Next, holes 3 as shown in FIG. 2 are made in the insulating sheet 2 using a pan 1, a drill, etc. (J, cleaning is performed).

After cleaning, the surface of the adhesive 2 is chemically phased with a roughening solution consisting of hydrofluoric acid, small sodium chromate, etc. as shown in FIG.

After chemical roughening, plating resists 1 to 4 are screen printed on arbitrary locations on the surface of the adhesive 1 as shown in FIG.

Mark plating registers 1 to 4 (after 6 steps, insulating sheet 1-2 is immersed in an electroless plating solution consisting of copper sulfate, formaldehyde, a complexing agent, caustic soda, soda cyanide, etc., and electroless plating is performed. As shown in FIG. 5, a plating layer 5 is simultaneously formed on the surface and the inner wall of the hole.

For example, a wire (a 50-mesh cloth-like thin material made of 155μ tile polyester cord) is coated with a plating catalyst-containing adhesive (
An insulating sheet with a thickness of about 0.3 mm impregnated and coated with 1-I A-21) manufactured by Hitachi Chemical Co., Ltd.! -, holes are formed at any location in the process of making this insulating sheet, and cleaning is performed.
Plating resist ink (manufactured by Hitachi Chemical Co., Ltd. 1-(GM
-028K) to form a reverse pattern of the circuit, chemically roughen it, and further perform electroless plating treatment for 20 hours to form a plating layer.MrL-1070
I repeated impact test 1 75 times in accordance with the regulations and found no problems.

Further, a similar test was conducted on a printed wiring board manufactured by applying the same treatment as above using a 70-mesh cloth-like thin material made of polyester 1ili navy blue with a wire diameter of 131 μm, but no problems were found.

(Effects of the Invention) As described above, according to the present invention, since the insulating sheet 1 containing a plating catalyst is used as a flexible substrate,
'R3S! A highly reliable printed wiring board llllll method with simple i steps can be obtained.

[Brief explanation of the drawing]

1 to 5 show each manufacturing step of an embodiment of the present invention,
Figure 1 is a front sectional view of the insulating sheet, Figure 2 is a front sectional view of the insulating sheet with holes, Figure 3 is a front sectional view of the insulating sheet after roughening, and Figure 4 is the plating resist. Mark C11
FIG. 5 is a front sectional view of the insulating sheet i after l, and FIG. 5 is a front curved view of the printed wiring board. 1... Adhesive, 2... Insulating sheet, 3...
Hole, 4... Plating resist, 5... Plating layer. Patent applicant Hitachi Capacitor Co., Ltd. Figure 1 Figure 5

Claims (1)

[Claims] (1) In a method for manufacturing a printed wiring board in which a circuit can be formed on an insulating substrate by electroless plating, a process of impregnating and coating a thin material made of insulating fibers with an adhesive containing a plating catalyst to form an insulating sheet A method for producing a printed wiring board, comprising the steps of: providing holes in the insulating sheet; and after the step, simultaneously forming a plating layer on the surface of the insulating sheet and in the holes by electroless plating.