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, 1985
Filed:
Dec. 14, 1983
Michinori Tsuchida, Ibaraki, JP;
Toshihide Shimizu, Urayasu, JP;
Ichiro Kaneko, Ibaraki, JP;
Tokuji Abe, Ibaraki, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
The invention provides a very simple but effective means for preventing surface oxidation of fine metal powders by coating the metal powder with an organic dye. This method of surface-oxidation prevention is particularly useful for the preparation of a so-called plastic magnet which is prepared by uniformly blending a dye-coated fine powder of a magnetic alloy such as a rare earth-cobalt based permanent magnet with a thermoplastic resin such as a nylon or polyphenylene sulfide resin followed by molding the resin-powder blend into a magnet form. In addition to the remarkably improved magnetic properties of the thus prepared plastic magnets as a result of high loading and absence of degradation by oxidation, the danger of spontaneous ignition of the magnet powder in molding can be eliminated almost completely. Surface treatment of the dye-coated magnet powder with a silicone fluid gives further improved results.