| 摘要 |
PROBLEM TO BE SOLVED: To provide a homogeneous copper powder of high quality which has a remarkably narrow particle size distribution width, suppresses the content of impurities, and has high conductivity.SOLUTION: There is provided a copper powder obtained by a method for producing a copper powder comprising: adding a hydrazine-based reducing agent to a copper salt compound slurry which is obtained by adding an alkaline solution to a copper salt aqueous solution to obtain a cuprous oxide slurry; and adding a phosphorous compound to a reaction slurry in such a manner that the molar ratio of phosphorous to copper satisfies P/Cu=0.0001 to 0.003 by the time a final reduction reaction is completed in a process where the hydrazine-based reducing agent is again added to a washed cuprous oxide slurry obtained by washing the cuprous oxide slurry with water to be re-slurried. The copper powder has a volume-cumulative average particle diameter Dof 0.1 μm to 5.0 μm by a laser diffraction scattering particle size distribution measuring method. A value of SD/Dexpressed by using a standard deviation SD of particle size distribution measured by the laser diffraction scattering particle size distribution measuring method and the volume-cumulative average particle diameter Dis 0.2 to 0.5. |
