Patent ID: 8309287
Filing Date: 2012-11-13
Classification: G03G

Abstract:
1. A developing roller comprising: a mandrel; an elastic layer; and a cover layer functioning as a surface layer, wherein the cover layer comprises a silicon oxide film containing a carbon atom chemically bonded to a silicon atom, wherein, in the silicon oxide film, the proportion of the total number of the existing elements of a silicon atom, an oxygen atom, a carbon atom and a hydrogen atom to the number of all detected elements, as detected by using a high-frequency glow discharge light-emission surface analysis method, is 90% or more, and wherein the silicon oxide film has an abundance ratio of an oxygen atom chemically bonded to a silicon atom to silicon atoms, (O/Si), of 0.65 to 1.95, an abundance ratio of a carbon atom chemically bonded to a silicon atom to silicon atoms, (C/Si), of 0.05 to 1.65, and, has a ratio of the maximum value to the minimum value of the abundance ratio (C/Si) in a thickness direction of the cover layer of 1.5 to 33.0.