Metal powder production method, metal powder produced thereby, conductive paste and multilayer ceramic electronic component

摘要

Fine, highly-crystallized metal powder is produced at low cost and high efficiency by a method involving: ejecting raw material powder composed of one or more kinds of thermally decomposable metal compound powders into a reaction vessel through a nozzle together with a carrier gas and producing a metal powder by heating the raw material powder at a temperature T2 which is higher than the decomposition temperature of the raw material powder and not lower than (Tm−200°) C. where Tm is the melting point (° C.) of the metal to be produced, while allowing the raw material powder to pass through the reaction vessel in a state where the raw material powder is dispersed in a gas phase at a concentration of 10 g/liter or less, wherein an ambient temperature T1 of a nozzle opening part is set to a temperature of 400° C. or higher and lower than (Tm−200°) C.

主权项

1. A method for producing a crystallized metal powder, the method comprising:
ejecting a raw material powder composed of one or more kinds of thermally decomposable metal compound powders into a reaction vessel through a nozzle together with a carrier gas under the condition of V/S >600, where V represents a flow rate per unit time of the carrier gas (liter/min) and S represents a cross-sectional area of a nozzle opening part (cm2); and producing a metal powder by heating the raw material powder at a temperature T2 which is higher than a decomposition temperature of the raw material powder and not lower than (Tm−200°) C. where Tm is the melting point (° C.) of the metal to be produced, while allowing the raw material powder to pass through the reaction vessel in a state where the raw material powder is dispersed in a gas phase at a concentration of 10 g/liter or less, wherein an ambient temperature T1 of the nozzle opening part is set to a temperature which is higher than the decomposition temperature of the raw material powder and is at least 400° C. and lower than (Tm−200°) C. and the raw material powder is exposed to the temperature T1 immediately after being ejected into the reaction vessel wherein the temperature T1 causes the raw material powder to undergo pyrolysis and generate a pyrolysis gas.