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:
Jun. 24, 2003
Filed:
Sep. 30, 1999
Tom J. Hall, Arlington Heights, IL (US);
Michael J. Weber, Arlington Heights, IL (US);
Littelfuse, Inc., Des Plaines, IL (US);
Abstract
The present invention provides a method for heat treating a polymer PTC composition to increase the peak resistivity of the composition making it especially well suited for high voltage applications. A polymer PTC composition having a melting point temperature T is provided. The temperature of the polymer PTC composition is increased at a rate, r , to a temperature greater than T . The temperature of polymer PTC composition is held at the temperature greater than T for a predetermined period of time. Then the temperature of the polymer PTC composition is decreased to a temperature less than T at a rate, r , wherein r is greater than r .