Toda Kogyo Corporation

Toyobo Co., Ltd.

Takeshi Yatsuka

Yasuo Kakihara

Chiho Ito

Hirotoshi Kizumoto

Koji Shoki

An object of the present invention is to provide a conductive coating film formed on a polyimide-based insulating substrate by using a metal powder paste which can exhibit a good conductivity and good adhesion to the insulating substrate. By forming a resin cured layer having a solvent-soluble content of not more than 20% by weight and a thickness of not more than 5 &#x3bc;m on a polyimide-based insulating substrate; forming a metal powder-containing coating layer on the resin cured layer by using a metal powder paste; and then subjecting the resulting coating layer to heat treatment with superheated steam, it is possible to obtain a conductive coating film which can exhibit a good conductivity and good adhesion to the insulating substrate.

Process for producing conductive coating film, and conductive coating film

There are provided copper particles and a copper paste for a copper powder-containing coating film which can be subjected to electroless metal plating without using an expensive catalyst such as palladium, and a process for producing a conductive coating film by subjecting a copper powder-containing coating film formed by using the copper paste to electroless metal plating or heat treatment with superheated steam. The present invention relates to a process for producing a conductive coating film comprising the step of forming a coating film on an insulating substrate using copper particles having an average particle diameter of 0.05 to 2 &#x3bc;m as measured by observation using SEM in which a BET specific surface area value (SSA) (m/g) and a carbon content (C) (% by weight) of the copper particles satisfy a relationship represented the following formula [1]: C/SSA&#xb7;7&#xd7;10[1], and a copper paste comprising the copper particles; drying the coating film to obtain a copper powder-containing coating film; and then subjecting the resulting coating film to electroless metal plating or heat treatment with superheated steam.

Growing community of inventors

Otake, Japan

Takeshi Yatsuka