Patent ID: 9348246
Filing Date: 2016-05-24
CPC Classification: G03G

Claim Text:
1. A developing apparatus for developing an electrostatic latent image formed on a surface of an electrostatic latent image bearing member to form a toner image on the surface of the electrostatic latent image bearing member, wherein the developing apparatus comprises a toner for developing the electrostatic latent image, a toner carrying member for carrying the toner, and a regulating member for regulating a layer thickness of the toner carried by the toner carrying member, the toner is a magnetic toner comprising a toner particle containing a binder resin and a magnetic member, a first fine silica particle having a number average primary particle diameter (D1) of 5 nm or more and 20 nm or less, and a second fine silica particle having a number average primary particle diameter (D1) of 40 nm or more and 200 nm or less, the second fine silica particle is a fine silica particle produced by a sol-gel method, the toner has a total energy of 270 mJ/(g/ml) or more and 355 mJ/(g/ml) or less, the toner carrying member has a substrate, an elastic layer and a surface layer comprising a urethane resin, and the urethane resin has a partial structure derived from a reaction of a compound represented by the following structural formula (1) with a polyisocyanate: wherein n denotes an integer of 1 or more and 4 or less, each R (a) a hydroxyalkyl group having 2 or more and 8 or less carbon atoms; (b) an aminoalkyl group having 2 or more and 8 or less carbon atoms; and (c) a group represented by the following structural formula (2), and R wherein m denotes an integer of 2 or more and 3 or less, and R