Search International and National Patent Collections
|1. (WO2014199480) Ta POWDER, PRODUCTION METHOD THEREFOR, AND Ta GRANULATED POWDER|
|Applicants:||ISHIHARA CHEMICAL CO., LTD.
|Title:||Ta POWDER, PRODUCTION METHOD THEREFOR, AND Ta GRANULATED POWDER|
[Problem] To provide: a method for producing a Ta powder for use in tantalum solid electrolytic capacitors capable of stably obtaining CV values exceeding 220k; said Ta powder; and a Ta granulated powder therefrom. [Solution] A method whereby TaCl5 is heated and vaporized, then reduced using H2 gas to produce Ta powder, to obtain: a Ta powder for electrolytic capacitors, comprising a tetragonal β-Ta single phase or a mixed phase comprising said β-Ta and a cubic β-Ta, and having an average particle diameter of 30-150 nm; and a Ta granulated powder comprising granulated Ta powder. In said method, the supply rate for TaCl5 vapor passing through a reaction site cross-sectional area of 1 cm2 in one minute is 0.05-5.0 g/cm2·min, the TaCl5 vapor is retained at the reduction reaction site for 0.1-5 seconds, and the TaCl5 reduction temperature is 1,100-1,600°C.