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:
Oct. 01, 2002
Filed:
Dec. 17, 1999
Kazuyuki Hayashi, Hiroshima, JP;
Keisuke Iwasaki, Hiroshima, JP;
Yasuyuki Tanaka, Hiroshima, JP;
Hiroko Morii, Hiroshima, JP;
Toda Kogyo Corporation, Hiroshima-ken, JP;
Abstract
The present invention relates to titanium oxide particles having an average particle size of not more than 0.3 &mgr;m, and a BET specific surface area of 15 to 200 m /g, containing a soluble sodium salt of not more than 230 ppm, calculated as Na, and a soluble sulfate of not more than 150 ppm, calculated as SO , and having a pH value of not less than 8. The titanium oxide particles of the present invention are suitable as non-magnetic particles for a non-magnetic undercoat layer of a magnetic recording medium which uses magnetic particles containing iron as a main ingredient, and even more particularly, are suitable as non-magnetic particles for a non-magnetic undercoat layer of a magnetic recording medium which uses magnetic particles containing iron as a main ingredient, show an excellent dispersibility in a binder resin, contain only a small amount of soluble sodium salt and soluble sulfate, and have a pH value of not less than 8.