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. 23, 1996
Filed:
Jan. 13, 1994
Applicant:
Inventors:
Jacques Lewiner, 92210 Saint-Cloud, FR;
Didier Perino, 92500 Rueil-Malmaison, FR;
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; H05H / ;
U.S. Cl.
CPC ...
428450 ; 427579 ; 427578 ; 4273977 ; 427573 ; 427574 ;
Abstract
For making an SiO.sub.2 electret, a layer of SiO.sub.2 is formed on a solid substrate (5) by chemical vapor deposition in a vapor phase starting from a plasma containing silicon and oxygen and the layer so formed (10) is subjected to a thermal treatment by raising its temperature to above 100.degree. C. during a time period longer than 1 hour, before being electrically charged.