Invention patent:Method for producing ferric oxide black with steel rolling oil sediments

No. 39357

Total 2 pages

Certificate for Invention Patent

Title of invention: Method for producing ferric oxide black with steel rolling oil sediments

Inventor: Wan Xiaoping Huang Shengyu

Patent No. ZL 93 1 19424.5 International patent main classification No. C01G 49/08

Date of patent application: Oct. 28, 1993

Patentee: WISCO

The patent has been examined and checked by the Office according to the Patent Law of the People’s Republic of China, now the patent right is granted accordingly.

Director: GAO Lulin (signature)

Patent Office of the People’s Republic of China(seal)

Dec. 26, 1997

Special Seal for Deducting Stamp Tax of Beijing Haidian District Local Taxation Bureau, Bureau of Patent of China (seal)