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:
Oct. 14, 1997
Filed:
Sep. 20, 1996
Leslie F Trudeau, Waverly, NY (US);
Charles F Chenot, Towanda, PA (US);
Richard G Gingerich, Towanda, PA (US);
Osram Sylvania Inc., Danvers, MA (US);
Abstract
A fine, largely beta phase calcium pyrophosphate powder for, e.g., a diffuser coating for the interior surface of lamp envelopes. The powder is useful for electrostatic deposition of such coatings under varying conditions of environmental humidity. A process for the synthesis of the calcium pyrophosphate is also disclosed. Dibasic calcium orthophosphate (monetite) is dissolved in a dilute aqueous hydrochloric acid solution and spray-dried to form a calcium phosphate powder of spherically shaped hollow particles. The calcium phosphate powder is fired in air to convert the calcium phosphate powder to a spherical calcium pyrophosphate powder including the beta phase as a major component and the gamma phase as a minor component. For a diffuser coating, the poder is sonicated to fragment a portion of the hollow particles.