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:
May. 11, 2010
Filed:
Mar. 21, 2008
Shenglei Che, Tokyo, JP;
Kentaro Mori, Tokyo, JP;
Masahiko Watanabe, Tokyo, JP;
Takuya Aoki, Tokyo, JP;
Tomofumi Kuroda, Tokyo, JP;
Shenglei Che, Tokyo, JP;
Kentaro Mori, Tokyo, JP;
Masahiko Watanabe, Tokyo, JP;
Takuya Aoki, Tokyo, JP;
Tomofumi Kuroda, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
Provided is a process for producing a MnZn-base ferrite comprising: firing a compacted raw material to produce the MnZn-base ferrite, wherein the firing comprises, in the following order: a heating phase comprising gradually bringing a firing temperature from room temperature up to a maximum temperature; a maximum temperature holding phase comprising maintaining the maximum temperature for a period of time, wherein a partial pressure of oxygen (p2) at the maximum temperature holding phase is greater than an equilibrium partial pressure of oxygen (p1) as follows: p2>p1, wherein the equilibrium partial pressure of oxygen (p1) is represented by the following equation: log(p1)=log(PO)=a−b/T, wherein POis measured in a unit of %, and T is measured in a unit of absolute temperature K; and a cooling phase comprising gradually bringing the maximum temperature down to near room temperature, wherein a partial pressure of oxygen (p3) at the cooling phase is operated at an equilibrium partial pressure of oxygen based on the equation log(p3)=a−b/T.