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:
Sep. 24, 2002
Filed:
Oct. 08, 1999
Philip D. Eitzman, Lake Elmo, MN (US);
Alan D. Rousseau, Stillwater, MN (US);
Marvin E. Jones, Grant, MN (US);
Seyed A. Angadjivand, Woodbury, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A method of charging fibrous webs with nonaqueous polar liquids. A web that contains nonconductive fibers is wetted with a nonaqueous polar liquid The web is then substantially dried to provide a fibrous electret web. The fibrous electret web can be used as a filter in a filtration face mask that is adapted to cover the nose and mouth of the wearer. The present method has the advantage over known charging methods in that the nonaqueous liquid requires less energy for drying than is required for aqueous liquids. Additionally, many filter webs can be directly wetted with nonaqueous liquids, which cannot be easily wetted with aqueous liquids.