PURPOSE: To enhance uniform dispersion by using metal superfine particles with less than a specified particle size in an organic solvent.
CONSTITUTION: Valves (hereinafter referred to as V) 3, 4 are closed, and exhaust is conducted from V5 to make an evaporating chamber 1 and a recovering chamber 2 into reduced pressure. Helium gas is introduced from V3 to continue the exhaust from V5, α-terpineol vapor 10 is introduced from V4, and copper 6 in a crucible 6 is heated by a high frequency induction heating device 8 to generate a copper vapor 9, which is then carried from the chamber 1 to the chamber 2 and concentrated therein, forming copper superfine particles. They are mixed with a steam 10 and deposited as copper superfine particles 12 stabilized on a cooling plate 22 cooled to a low temperature by a coolant 13. The used metal is at least one metal of copper, indium, tin, titanium, gold, silver, nickel, zinc, tantalum, chromium, tungsten, palladium, platinum, iron, cobalt, and silicate, or alloys thereof. The size of the precipitated metal particles, which is controlled by pressure of the inert gas, metal vapor pressure, and evaporation temperature, is preferably less than 1000. Hence, a metal paste uniformly dispersed at a high density can be obtained.
OSHIMA MICHIHIRO
SETOGUCHI KAZUHIRO
| JPS59146103A | 1984-08-21 |