JPH02303185A - Manufacture of multilayer printed wiring board - Google Patents

Abstract

PURPOSE:To eliminate a defective exterior view of a multilayer printed-wiring board and to prolong a life of a molded plate by a method wherein, in a laminated body where prepregs are piled up on each surface and/or each rear surface of two or more inner-layer material, a caulking pin is arranged in a required position and an outer-layer material is arranged on an outermost layer, the molded plate is arranged in a position not coming into contact with the caulking pin and this assembly is laminated and molded. CONSTITUTION:As an inner-layer material, an electrical circuit is formed on a copper-foil face such as a one-sided copper-clad laminated sheet, a double-sided copper-clad laminated sheet or the like. As a prepreg, a woven cloth, a nonwoven cloth or a mat composed of an inorganic fiber such as glass, asbestos or the like, an organic synthetic fiber such as a polyester, a polyamide or the like or a natural fiber, a sheet of paper or a base material combining these is impregnated with a single substance, a denatured substance or a mixed substance of a phenolic resin, a cresol resin, an epoxy resin or the like; the prepreg is then dried. As an outer-layer material, the one-sided copper-clad laminated sheet, a copper foil or the like is used. Caulking pins are installed preferably at four corner parts of the inner- layer material and the prepreg. It is required to arrange and install a molded sheet so as not to come into contact with the caulking pins; the sheet is installed at the inside of the positions of the caulking pins.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a multilayer printed wiring board used in electronic equipment, electric equipment, convenience stores, communication equipment, etc.

[Conventional technology]

Conventional multilayer printed wiring boards, such as 6RA printed wiring boards, are first
Inner layer material 2゜prepreg 3 with circuit 1 as shown in the figure
The caulking pin 4 is placed at the required position for alignment, the outer layer material 6 is placed on the outermost layer, and then the metal forming plate 6 is placed.
Although it is obtained by lamination molding by sandwiching it between the two, there are scratches on the surface of the molding plate 6 at the part where the caulking pin 4 contacts the molding plate 6.
This will cause dents and scratches on the surface of the multilayer printed wiring board during the next lamination molding.
There was a problem in that the dents were transferred, giving the product a poor appearance.

[Problem that the invention seeks to solve]

As described in the section on the prior art, in the conventional lamination molding method, it was inevitable that the multilayer printed wiring board would have frequent appearance defects. The present invention has been made in view of the above-mentioned problems in the prior art, and its purpose is to provide a multilayer printed wiring board that can eliminate the appearance defects of the multilayer printed wiring board and extend the life of the molded plate. The purpose of this invention is to provide a method for manufacturing the same.

[Means for solving problems]

The present invention is a laminate in which prepregs are stacked on the upper and/or lower surfaces of two or more inner layer materials, swiveling pins are arranged at required positions, and an outer layer material is arranged on the outermost layer, in which a molded plate is arranged at a position that does not contact the swiveling pins. The above object can be achieved because of the method for producing a multilayer printed wiring board, which is characterized in that the multilayer printed wiring board is laminated and formed.The present invention will be described in detail below.

Inner layer materials used in the present invention include single-sided copper-clad laminates, double-sided steel-clad laminates, etc., in which an electric circuit is formed on the copper foil surface, and prepregs include phenolic resin, cresol resin, epoxy resin, and unsaturated polyester. resin, polyimide resin,
Polybutadiene resin, polyphenylene oxide resin,
Fluorinated resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polyphenylene sulfide F
Woven fabrics, non-woven fabrics, mats, paper or It is obtained by impregnating and drying these combination base materials. As the outer layer material, a single-sided copper-clad laminate, copper foil, etc. can be used. The caulking pin position should preferably be provided at the four corners of the inner layer material or prepreg.The molding plate must be placed so that it does not touch the caulking pin, so the size of the molding plate should be reduced so that it is inside the caulking pin position. Alternatively, it can be formed into a molded plate shape with a notch provided at the caulking pin position. By doing so, it is possible to prevent scratches and dents from occurring at the contact portion between the caulking pin and the molded plate. As the lamination molding method, any lamination molding method such as a multistage press method, a press method, a multi-roll method, a double belt method, a continuous pressureless molding method, etc. can be used.

An embodiment of the present invention will be described below based on an illustrated embodiment.

Embodiment FIG. 2 is a simplified sectional view showing an embodiment of the present invention. As shown in FIG. 2, an epoxy resin glass cloth base inner layer material 2.21 having a circuit 1 and a thickness of 0°3M and the inner layer material 2.2/
The epoxy resin glass cloth base material prepreg 3 with a thickness Q of 111 ffl is layered in between, and the inner layer material 2.2 is layered.
An epoxy resin glass cloth base material prepreg 3 with a thickness of 0.1 fl is placed on the outside of the 1, and the required positions are aligned with caulking pins 4, and then a copper foil 5 with a thickness of 0.035 m is placed on the outermost layer. Lamination molding was carried out for 90 minutes at 5165°C at 4' k/d and 4' k/d by sandwiching between 3 fl thick stainless steel forming plates 6 so that the parts were inside the crimping pin 4 position of the body.
A layer printed wiring board was obtained.

Comparative Example A 6-layer printed wiring board was obtained by processing the molded plate 6 of the example in the same manner as in the example except for the large plate 1 so that the molded plate 6 was placed outside the caulking pin position.

Table 1 shows the appearance defects and molded plate life of the 6-layer printed wiring boards of Examples and Comparative Examples.

〔Effect of the invention〕

The present invention is constructed as described above. - The method for manufacturing a multilayer printed wiring board having the configuration described in the claims has the effect of reducing appearance defects and extending the life of the molded plate.

[Brief explanation of drawings]

FIG. 1 is a simplified sectional view when materials are laminated by a conventional method, and FIG. 2 is a simplified sectional view when materials are laminated according to an embodiment of the present invention. 1 is an inner layer circuit, 2 is an inner layer material, 3 is a prepreg, 4 is a caulking pin%, 5 is an outer layer material, and 6 is a molded plate.

Claims (1)

[Claims] (1) In a laminate in which prepregs are stacked on the upper and/or lower surfaces of two or more inner layer materials, swiveling pins are placed at required positions, and the outer layer material is placed on the outermost layer, a molded plate is placed at a position that does not contact the swiveling pins. 1. A method for manufacturing a multilayer printed wiring board, characterized in that the multilayer printed wiring board is laminated and formed.