JPH02303196A - Multilayer printed wiring board - Google Patents

Abstract

PURPOSE:To obtain a multilayer printed-wiring board whose hole processing property and heat-resistant property are excellent by a method wherein laminated bodies where outer-layer materials are arranged on the surface and/or the rear surface of an inner-layer material via a prepreg of a nonwoven cloth base material are laminated and united. CONSTITUTION:Laminated bodies where outer-layer materials are arranged on the surface and/or the rear surface of an inner-layer material via a prepreg of a nonwoven cloth base material are laminated and united. As the prepreg of the nonwoven cloth base material of an inorganic fiber nonwoven cloth such as a glass nonwoven cloth, a sheet of glass paper or the like or an organic synthetic fiber nonwoven cloth such as a polyester, a polyamide, a polyvinyl alcohol, a polyacryl or the like is impregnated with a resin varnish; this assembly is dried. As the outer-layer materials, one-sided metal-clad laminated sheets or metal foils are used. As a laminating and molding means, an arbitrary laminating and molding means such as a multistage press method, a press method, a multiroll method, a double-belt method, a continuous nonpressure molding method or the like is used.

Description

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

[Conventional technology]

Conventional multilayer printed wiring boards are made of paper or glass cloth based prepreg and an inner layer material obtained by processing a laminate made of the prepreg, and those made of paper base material are punched.
For those made of glass cloth base material, holes such as through holes are formed by drilling. Paper substrates have advantages and disadvantages, such as easy hole-machining and good production efficiency, but limited heat resistance, while glass cloth substrates have excellent heat resistance but are difficult to hole-make and have poor production efficiency. .

[Problem that the invention seeks to solve]

As described in the section on conventional technology, conventional multilayer printed wiring boards have advantages and disadvantages in performance and workability.

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 with excellent hole machinability and heat resistance.

[Means for solving problems]

The present invention is a multilayer printed wiring board characterized in that it is formed by laminating and integrating a laminate in which an outer layer material is disposed on the upper and/or lower surface of an inner layer material via a nonwoven base material prepreg, and thus achieves the above object. The present invention will now be described in detail.

Inner layer materials used in the present invention include phenolic resin, cresol resin, epoxy resin, unsaturated polyester resin,
Melamine resin, polyimide, polybutadiene, polyamide, polyamideimide, polysulfone, polyphenylene sulfide, polyphenylene oxide, polybutylene terephthalate, polyether ether ketone, fluorine (1) for resin varnishes such as fats alone, silica, mixtures, etc. Calcium carbonate, aluminum hydroxide as needed.

Resin varnishes containing fillers such as clay, talc, silica, alumina, pulp, and cotton powder are made from inorganic fibers such as glass and asbestos, organic synthetic fibers such as polyester, polyamide, polyvinyl alcohol, and acrylic, and natural fibers such as cotton. Metal foil is placed on the upper and/or lower surfaces of the required number of impregnated and dried prepregs stacked on woven fabric, non-woven fabric, mat, paper, or a combination of these substrates, etc., and then electrical circuits are attached to the metal foil. It was formed. The nonwoven fabric base material prepreg is a nonwoven fabric base material such as an inorganic fiber nonwoven fabric such as glass nonwoven fabric or glass vapor, or an organic synthetic fiber nonwoven fabric such as polyester, polyamide, polyvinyl alcohol, or polyacrylic, impregnated with the above resin varnish and dried. .

As the outer layer material, a single-sided metal-clad laminate or metal foil can be used. As the layer forming means, any ff layer forming means can be used, such as a multistage press method, a press method, a multi-roll method, a double belt method, and a continuous pressureless forming method.

The following is a description based on all the embodiments of the present invention.

Example: Electric circuits are formed on both sides of a double-sided copper-clad epoxy resin glass cloth base laminate with a thickness of 1 tttx to form an inner layer material, and 2 gates of epoxy resin glass nonwoven fabric prepreg with a thickness of Q are formed on the upper and lower surfaces of the inner layer material. A PR layer with a 0.018 m thick silver foil placed through each layer was molded at a pressure of 40 kg/d.
Lamination molding was performed at 165° C. for 60 minutes to obtain a 4-layer printed wiring board.

Comparative Example: One sheet of epoxy resin glass cloth prepreg with a thickness of 0 and 2 nm was interposed on the upper and lower surfaces of the same inner layer material as in the example, respectively, and the thickness was Q.
A laminate with 018fl copper foil was molded under a molding pressure of 40Kq.
/d, lamination molding was performed at 165° C. for 60 minutes to obtain a 4-layer printed wiring board.

Table 1 shows the performance of the four-layer printed wiring boards of Examples and Comparative Examples.

〔Effect of the invention〕

The present invention is constructed as described above. A multilayer printed wiring board having the structure described in the claims has the effect of having good heat resistance and improving hole-drilling workability.

Claims (1)

[Claims] (1) A multilayer printed wiring board characterized in that it is formed by laminating and integrating a laminate in which an outer layer material is disposed on the upper and/or lower surface of the inner layer material via a nonwoven base material prepreg.