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. 11, 2009
Filed:
Sep. 24, 2004
Tetsunori Mitsuoka, Tondabayashi, JP;
Toshiaki Kagawa, Nara, JP;
Tetsunori Mitsuoka, Tondabayashi, JP;
Toshiaki Kagawa, Nara, JP;
Sharp Kabushiki Kaisha, Osaki-Shi, JP;
Abstract
A fixing device () includes a fixing roller () which is in contact with an unfixed image formed on a printing medium () with toner () and a pressure roller () which is in contact with the fixing roller (). The fixing device () causes the fixing roller () and the pressure roller () to sandwich and feed the printing medium (), so as to fix the unfixed image onto the printing medium (). The fixing device () gives a holding electric field which is an electric field in a direction for holding a reverse polarity toner () on the printing medium (). The reverse polarity toner () has a polarity opposite to that of the toner () which forms an image on the printing medium. Thus, it is possible to avoid a troulile caused by the adhesion of the reverse polarity toner () to the pressure roller (). Therefore, it is possible to avoid an image failure caused by the reverse polarity toner, maintain a normal image forming operation, and secure a satisfactory image quality and the life of each means even in long-term use.