Patent Number: 8,722,303

Title: Image forming method

Abstract: An image forming method using a two component developing system is provided in which a print speed is not less than 300 mm/s, a peak-to-peak voltage of an AC component in a developing bias is not more than 1.3 kV, a sufficient image density can be ensured, and a recorded image having a small amount of magnetic carrier remaining on the image and having high image quality can be obtained. A magnetic carrier that forms a two component developer contains a magnetic core and a resin. The magnetic core is a ferrite containing Sr and Ca inside thereof at the same time, having a small crystal grain diameter, a high density crystal-grain boundary structure, and an extremely large capacitance of the grain boundary. Use of the ferrite can provide the above method.

Inventors: Horie; Juun (Tokyo, JP), Yamamoto; Takeshi (Yokohama, JP), Baba; Yoshinobu (Yokohama, JP), Ishigami; Koh (Mishima, JP)

Assignee: Canon Kabushiki Kaisha

International Classification: G03G 9/08 (20060101)

Expiration Date: 5/13/12018