Patents Examined by Lori Freeman
  • Method for production of oxidation-resistant silicon nitride material
    Patent number: 4853204
    Abstract: An oxidation-resistant silicon nitride material possessing a surface layer of a phase of closely packed crystals is produced by a procedure which comprises covering the surface of a silicon nitride substrate with a layer of an alkali metal compound, firing the coated substrate at a temperature of between 800.degree. C. and 1,300.degree. C., thereby forming an alkali metal-containing vitreous coating layer on the surface of the silicon nitride substrate, and thereafter removing the coating layer.
    Type: Grant
    Filed: December 16, 1987
    Date of Patent: August 1, 1989
    Assignee: Agency of Industrial Science & Technology, Ministry of International Trade & Industry
    Inventors: Nobuyuki Azuma, Minoru Maeda, Kazuo Nakamura
  • Process for recovery of silicon from a reaction mixture
    Patent number: 4777030
    Abstract: A process is described for the recovery of silicon from a reaction mixture comprising silicon and an alkali metal fluoride.
    Type: Grant
    Filed: July 24, 1985
    Date of Patent: October 11, 1988
    Assignee: Enichem, S.p.A.
    Inventor: Kenneth M. Sancier