The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 1979
Filed:
Jan. 25, 1978
James D McGilvery, Etobicoke, CA;
Vicram P Singh, Scarborough, CA;
ERCO Industries Limited, Islington, CA;
Abstract
Red phosphorus, usually in amorphous form, is obtained by heating liquid white phosphorus at a temperature of between 250.degree. and 590.degree. C. while the phosphorus is subjected to a pressure greater than the theoretical vapor pressure of white phosphorus at the heating temperature. The application of such pressure minimizes phosphorus vapor formation during the conversion to red phosphorus. The process may be carried out by feeding liquid white phosphorus into an extrusion head heated to the reaction temperature while subjecting the white phosphorus to the appropriate pressure in the extrusion head, the red phosphorus being extruded from the extrusion head into an inert atmosphere. Alternatively, molten white phosphorus in droplet form may be pumped into an inert immiscible heat exchange fluid, such as, lead, at the reaction temperature, the appropriate pressure applied in the fluid and particulate red phosphorus separated from the fluid.