JPS60257599A - Method of producing multilayer printed circuit 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 [Technical Field] The present invention relates to a method for manufacturing a multi-fat printed wiring board used in electrical equipment, electronic equipment, computers, etc.

[Background technology]

Conventionally, multilayer printed wire cutting boards have a thickness of about 0.1 m in order to have a large resin amount of 40-5 weight 96 (hereinafter simply referred to as %) on the circuit forming side of the inner layer material on which the circuit is formed. It is obtained by laminating a large number of resin-impregnated base materials made by impregnating a thin base material with resin, and then arranging them into a single-sided metal-clad laminate with the metal foil side facing outward, and then integrating them. Due to the large amount of resin in the resin-impregnated base material interposed between the material and the single-sided metal-clad laminate, the strain stress during resin curing is large, causing deformation of minute circuits, and causing damage to the resin plate side of the single-sided metal-clad laminate. Problems have been the manual peeling off of the attached release film, the impossibility of automating the process, and the reduction in efficiency due to the handling of a large number of resin-impregnated substrates.

[Purpose of the invention]

The purpose of the present invention is to improve the reliability of inner layer circuits,
It is an object of the present invention to provide a method for manufacturing a multilayer printed wiring board that can automate the process by not using a release film and improve efficiency by reducing the number of resin-metal substrates handled.

[Disclosure of the invention]

The present invention relates to a circuit forming side K of an inner layer material on which a circuit is formed.

Since this is a multilayer printed wiring board characterized by disposing and integrating the resin-layered metal foil through the required number of resin-impregnated base materials, the amount of resin in the resin-impregnated base material is Appropriate, the distortion stress during resin curing is small, it does not affect the inner layer circuit, and since RJA type film is not used, the process can be automated, and the number of resin-impregnated base materials handled can be reduced. The present invention will be described in detail below as it can achieve efficiency.

As the inner layer material forming the circuit used in the present invention, either a single-sided circuit inner layer material or a double-sided circuit inner layer material can be used, and furthermore, the circuit is formed on the circuit forming side of the inner layer material through the required number of resin-impregnated base materials. It is also possible to provide a super-multilayer printed wiring board. Examples of resins for the resin-impregnated base material include phenolic resin, cresol resin, epoxy resin, unsaturated polynisder resin, melamine resin, polyimide, polybutadiene,
Polyamides, fluorinated resins, polyphenylene saccharides, ruphides, etc. alone, mixtures, modified products, etc. can be used, and if necessary, water, methyl alcohol, acetone,
It contains solvents such as cyflohexanone and styrene. Base materials include glass, inorganic fibers such as asbestos, polynisdel, polyamide, polyvinyl alcohol,
The base materials include woven fabrics, non-woven fabrics, mats, cheesecloth, paper, or combinations thereof made of organic synthetic fibers such as polyacrylic fibers, natural fibers such as cotton, etc., but glass cloth with excellent dimensional stability is preferably used. This is desirable. Further, the amount of resin in the resin-impregnated base material needs to be between 1 and 2% glossy. That is, if it is less than I%, the resin cannot be smoothly filled between the inner layer circuits, and if it exceeds 35%, the strain stress when the resin hardens becomes large and the reliability of the inner layer circuits decreases. As the metal foil, it is necessary to use a metal foil made of copper, aluminum, stainless steel, iron, nickel, brass, etc. alone or in an alloy, and to provide a resin layer on one side with the resin used for the resin-impregnated base material. It is not necessary to use the same resin as that used for the resin-impregnated base material, and a different type of resin may be used. Although the thickness of the resin layer is not particularly limited, it is preferably 1 to 200 microns. That is, if it is less than 1 micron, it tends to be difficult to eliminate the smoothness of the glass cloth surface, and if it exceeds 200 microns, the amount of resin melted during molding increases.

The method of the present invention will be explained below using Examples.

Example: On both sides of an inner layer material consisting of an epoxy resin glass laminate with a thickness of 1 g and 1 j on which circuits were formed on both sides, a layer of resin with a thickness of 0% was applied.
．． A laminate in which two sheets of 18 M epoxy resin-impregnated glass cloth were interposed, and then a resin-coated copper foil coated with epoxy resin to a thickness of micrometers on one side of a 0.038 wx thick copper foil was formed. Lamination and heating molding was carried out at 165°C%40ψ- for 90 minutes to obtain a four-layer circuit board.

On both sides of the same inner layer material as in the conventional example, a resin mass % of 0.1
After inserting three sheets of 11EIII epoxy resin-impregnated glass cloth, manually remove a polyvarnish 5-film with a thickness of W micron that is in close contact with the resin plate side of a single-sided copper-clad epoxy resin glass laminate with a thickness of 1,01111. A laminate with the resin plate side peeled off facing the epoxy resin-impregnated glass cloth side was laminated and heat-molded at 166°C for 40#/Al2O minutes to obtain a four-layer circuit printed wiring board.

〔Effect of the invention〕

As is clear from Table 1, the efficiency of manufacturing the four-layer circuit printed wiring boards of the embodiment and the conventional example and the reliability of the inner layer circuits are as follows. The performance of the plate was well confirmed to be superior to that of the present invention.

Table 1 This is the ratio when the conventional method is set as 100.

Claims (2)

[Claims] (1) Resin Ik is placed on the circuit forming side of the inner layer material on which the circuit is formed.
:! tJ-' A method for manufacturing a multilayer printed wiring board, characterized by disposing and integrating a resin-layered metal foil through a required number of base materials impregnated with 85N. (2) The method for manufacturing a multilayer printed wiring board according to claim 1, wherein the resin layer thickness of the resin layer-coated metal foil is 1 to 200 microns.