Iron oxide particles and process for producing the same
Номер патента: CA2107524C
Опубликовано: 19-01-1999
Автор(ы): Eiichi Kurita, Hiromitsu Misawa, Kazuo Fujioka, Koso Aoki, Minoru Kozawa, Yoji Okano
Принадлежит: Toda Kogyo Corp
Опубликовано: 19-01-1999
Автор(ы): Eiichi Kurita, Hiromitsu Misawa, Kazuo Fujioka, Koso Aoki, Minoru Kozawa, Yoji Okano
Принадлежит: Toda Kogyo Corp
Реферат: Disclosed herein is iron oxide particles comprising: 100 parts by weight of material iron oxide particles having a specific surface area represented by the following formula (1): 6/(p~d3) x ~s (1) wherein p represents a specific gravity of said iron oxide particles, d3 represents an area-average particle diameter (0.1 µm ~ d3 ~ 1.0 µm) and ~s represents an area shape factor) (1.0 ~ ~s ~ 2.0); and 0.25 to 10 parts by weight (calculated as an oxide) of the fine particles of the oxygen compound, the fine particles of the hydrate or mixed fine particles thereof of one element selected from the group consisting of Al, Si, Zr and Ti, which are adhered to the surfaces of said iron oxide particles; the increment of said specific surface area of said iron oxide particles being 1 to 6 m2/g, and the increment of said specific surface area with respect to the amount of said fine particles being not less than 0.35.
Titanium oxide particles, substrate for magnetic recording medium and magnetic recording medium using the same
Номер патента: US6458452B1. Автор: Kazuyuki Hayashi,Keisuke Iwasaki,Hiroko Morii,Yasuyuki Tanaka. Владелец: Toda Kogyo Corp. Дата публикации: 2002-10-01.