Nisshin Steel Co., Ltd.

Hitachi, Ltd.

Kiichiro Katayama

Koji Wakabayashi

Akira Minato

Heihatiro Midorikawa

Masahiko Itoh

Yukio Uchida

Takehiko Ito

Kenichi Masuhara

Kazuhiro Takagi

Yasuharu Maeda

Hisao Kawase

Mituru Kubo

Toshinori Murakami

Yasuharu Meada

Method for forming insulating films on electromagnetic steel plates

The present invention provides an insulating film-forming composition in which a mixed resinous liquid obtained from a specific proportion of an aqueous emulsion of an acrylic resin and/or an acryl-styrene base resin and an aqueous dispersion of PAN free substantially from any emulsifier/dispersant is added to and mixed with an inorganic film-forming composition containing as the main component a chromate or a chromate plus a phosphate, which has conventionally been used in the prior art, in a specific proportion, and a method for forming an insulating film by coating and drying such a composition on an electromagnetic steel plate. A substantial portion of the starting materials can be commerically available products. With the composition, provided to have a longer pot life, and method of the present invention, an efficient coating can be carried out, while suppressing foaming to a consideraly low level, thereby obtaining an insulating film excelling in insulating properties and other film properties.

Compositions for forming insulating films on electromagnetic steel

An aluminum coated steel sheet having excellent formability and corrosion resistance comprising a steel substrate of a recrystallized structure, an Al--Si coating layer of a recrystallized structure on at least one surface of the substrate, and a discontinuous intermediate layer of Al--Fe--Si intermetallic compounds. The product may be conveniently produced by rolling an Al--Si hot dipped steel sheet and annealing the rolled sheet under suitably selected conditions.

Aluminum coated steel sheet and process for producing the same

A process for the partial hot dipping of a long steel strip is disclosed which comprises forming an oxidation-inhibiting film, oxygen-impermeable and thermally stable in a hot-dipping bath, which film is produced by the chemical reaction of an iron content in the steel strip with an oxidation inhibiting film-forming agent, such as an inorganic phosphoric acid compound, on a predetermined area of the steel strip surface, forming, as required, an intermediate layer comprising an inorganic binder, such as water glass, on the resulting film, forming a carbon-containing, plateing-stopping film as a top coat on the intermediate layer, and hot dipping the steel strip.

Process for partial hot dipping of steel strips

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Funabashi, Japan

Kiichiro Katayama