Patent · US Expired

Pyrolytic boron nitride article

US4690841A · kind A · utility

8Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 19, 1986
Grant dateSep 1, 1987
Priority date
Expiry dateFeb 19, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/13
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A pyrolytic boron nitride article has a uniform structure 0.5 or less nodules/cm.sup.2 in average all through the overall surface of the article and 2 or less nodules in any portion of a unit square centimeter on the surface of the article. The pyrolytic boron nitride article is produced by depositing boron nitride through a vapor phase, using a boron halide gas and an ammonia gas as the starting materials. In production, the ammonia gas or a gas mixture containing the ammonia gas is not contacted directly with graphite at 300.degree. to 1850.degree. C.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.