abstract |
A developer apparatus includes a developer carrying member, for carrying a developer to a developing portion, the developer carrying member including an electroconductive base and a resistance layer provided thereon; a developer feeding member for being supplied with a voltage to supply the developer to the developer carrying member; wherein a surface moving speed of the developer carrying member Vp [mm/sec], a resistance R 1 (Ω) of the developer carrying member when an electric current applied the developer carrying member is 0.04 Vp [μA], and a resistance R 2 (Ω) or the developer carrying member when the electric current applied to the developer carrying member is 4 Vp [μA], satisfy:n n r 1 /R 2 <15. |