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:
Jan. 19, 1999
Filed:
Jun. 09, 1997
Applicant:
Inventor:
Donald Keith Swanson, Wilmington, DE (US);
Assignee:
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01B / ; C03C / ;
U.S. Cl.
CPC ...
423335 ; 501 39 ; 502 10 ; 2330 / ;
Abstract
Internal porosity is created in dense SiO.sub.2 particles by heating a mixture of the particles with B.sub.2 O.sub.3 above the melting point of both mixture components. Resulting SiO.sub.2 particles have altered morphology, internal porosity, and a negative thermal expansion coefficient when heated.