Hitachi Chemical Company, Ltd.

Hitachi, Ltd.

Norio Okano

Akishi Nakaso

Kazuhito Kobayashi

Hiroshi Shimizu

Naoyuki Urasaki

Yoshiyuki Tsuru

Shigeharu Arike

Daisuke Fujimoto

Nobuyuki Ogawa

Mitsuhiro Inoue

Kouichi Tsuyama

Kazuhisa Otsuka

Toyoki Ito

Hiroshi Hasegawa

A prepreg comprising a semi-cured thermosetting resin and electrically insulating whiskers or short fibers dispersed in said semi-cured thermosetting resin, and if necessary, a carrier film attached or bound to said prepreg is suitable for producing multilayer printed circuit boards of reduced thinness, high wiring density and high connection reliability with high productivity and low production cost.

Prepreg for printed circuit board

A multilayer printed circuit board small in interlayer thickness, capable of fine wiring, minimized in IVH and BVH diameters, high in strength and also excellent in wire bonding workability can be produced by a process comprising the steps of coating a thermosetting resin varnish compounded with electrically insulating whiskers on a roughened side of a copper foil, semi-curing the resin by heating to form a thermosetting resin layer, integrally laminating it on an interlayer board in which plated through-holes and conductor circudits have been formed, and roughening the cured thermosetting resin layer on the via hole wall surfaces with a roughening agent.

Process for producing multilayer printed circuit board for wire bonding

A metal foil coated with flame sprayed ceramic is produced in high productivity by flame spraying a ceramic on a surface of a metal foil, while spraying the rear side of the metal foil to be flame sprayed with water from an array of water nozzles arranged across the metal foil for cooling and providing tension to the metal foil.

Process for producing metal foil coated with flame sprayed ceramic

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Tsukuba, Japan

Norio Okano