Patent ID: 7310492

Claim:
A fixing device comprising: a fixing member; a heat source for heating said fixing member; a pressure member urged against said fixing member so as to form a nip portion between said pressure member and said fixing member; and a release agent applying unit that applies a release agent to said fixing member or said pressure member, wherein said fixing member and said pressure member heat and press a printing medium that bears a toner image at said nip portion so as to fix said toner image to said printing medium, and wherein an amount A (weight parts) of a wax contained in said toner, and an amount B (mg/sheet) of said release agent applied to said fixing member or said pressure member by said release agent applying unit per printing medium of A4 size satisfy the following relationships (1) through (3): 0≦A≦20 (1) 0≦B≦1.0 (2) 8 ≦A +(12 ×B )≦32 (3), and wherein a surface roughness Rz (μm) of said fixing member satisfies the following relationships: 0<Rz≦1.0 (4) 0 <Rz/B ≦1.0 (5).