摘要 |
In a solder paste which is a mixture of a flux and low melting point metal particles, low melting point metal fine particles manufactured by a conventional method or apparatus therefor include particles having widely varying particle diameters. Accordingly, the solder paste could not completely fill the minute holes in a mask for application to minute solder portions by printing, or mask removability was poor. According to the present invention, a mixture of a heat resistant continuous phase liquid and coarse metal particles in molten state is passed through a porous membrane to form the coarse low melting point metal particles into fine particles with a predetermined diameter. An apparatus according to the present invention comprise a porous membrane between a heating and dispersing mechanism and a cooling mechanism, and a pressure vessel connected to the heating and dispersing mechanism for applying a high pressure to the heating and dispersing mechanism.
|