Title:
METHOD FOR PRODUCING TANTALUM POWDER, TANTALUM POWDER AND TANTALUM ELECTROLYTIC CAPACITOR
Document Type and Number:
WIPO Patent Application WO/2002/011932
Kind Code:
A1
Abstract:
A method for producing a tantalum powder, which comprises a high temperature heat treatment step of reducing tantalum potassium fluoride with sodium and subjecting the resultant reduced tantalum powder to a high temperature heat treatment in an inert atmosphere, a low temperature heat treatment step of pulverizing tantalum coagulants from the high temperature heat treatment step, adding magnesium to the resultant powder and subjecting the mixture to a low temperature heat treatment under a reduced pressure, and an acid washing step of washing the product with an acidic solution, wherein the high temperature heat treatment step is carried out at a temperature of 1000 ° or higher and lower than 1250 °, and the low temperature heat treatment step is carried out at a temperature of 700 ° to 1000 °. The method can be employed for producing a tantalum powder having a CV of 80,000 to 250,000 µFV/g, and further allows the production of a tantalum powder having a CV higher than 80,000 to 250,000 $g(m)FV/g.
Inventors:
MIZUSAKI YUJIRO (JP)
IZUMI TOMOO (JP)
IZUMI TOMOO (JP)
Application Number:
PCT/JP2001/006768
Publication Date:
February 14, 2002
Filing Date:
August 07, 2001
Export Citation:
Assignee:
SHOWA CABOT SUPER METALS K K (JP)
MIZUSAKI YUJIRO (JP)
IZUMI TOMOO (JP)
MIZUSAKI YUJIRO (JP)
IZUMI TOMOO (JP)
International Classes:
B22F9/20; B22F1/00; B22F5/00; B22F9/24; C22B34/20; C22C1/04; H01G9/052; (IPC1-7): B22F9/24; B22F1/00; B22F5/00; H01G9/042; H01G9/052
Foreign References:
| JPS61284501A | 1986-12-15 | |||
| US5605561A | 1997-02-25 | |||
| US4684399A | 1987-08-04 | |||
| JPS52107211A | 1977-09-08 |
Attorney, Agent or Firm:
Shiga, Masatake (Takadanobaba 3-chome Shinjuku-ku Tokyo, JP)
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