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:
Aug. 03, 2010
Filed:
Jun. 02, 2008
John M. Sebastian, Oakdale, MN (US);
Marvin E. Jones, Grant, MN (US);
Fuming B. LI, Woodbury, MN (US);
Shih-hung Chou, Maplewood, MN (US);
Nathan E. Schultz, Lakeland, MN (US);
Justin L. Keough, Vadnais Heights, MN (US);
Rahul R. Shah, Woodbury, MN (US);
Daniel A. Japuntich, St. Paul, MN (US);
John M. Sebastian, Oakdale, MN (US);
Marvin E. Jones, Grant, MN (US);
Fuming B. Li, Woodbury, MN (US);
Shih-Hung Chou, Maplewood, MN (US);
Nathan E. Schultz, Lakeland, MN (US);
Justin L. Keough, Vadnais Heights, MN (US);
Rahul R. Shah, Woodbury, MN (US);
Daniel A. Japuntich, St. Paul, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A method of making an electret article, from a polymeric article that has a zeta potential of greater than or less than −7.5 millivolts. The article is charged by contacting it with an aqueous liquid that has a pH and conductivity as follows: (i) if the article has a zeta potential of −7.5 mV or less, then the contacting liquid has pH greater than 7 and a conductivity of 5 to 9,000 microSiemens per centimeter; and (ii) if the article has a zeta potential of greater than −7.5 mV, then the contacting liquid has a pH of 7 or less and a conductivity of 5 to 5,500 microSiemens per centimeter. An electret article made in this manner can provide improved electret performance, particularly in electret filtration articles.