Ajinomoto Co., Ltd.

Shinko Electric Industries Co., Ltd.

Seiichiro Ohashi

Shigeo Nakamura

Eiichi Hayashi

Junichi Nakamura

Tadahiko Yokota

Takaaki Yazawa

Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 &#x3bc;m or below.

Production method of multilayer printed wiring board and multilayer printed wiring board

Multi-layer printed wiring boards may be produced by:

Process for producing multilayer printed wiring board

A production method of a multi-layer printed wiring board containing the following steps (1)-(5):

Growing community of inventors

Kawasaki, Japan

Seiichiro Ohashi