Patent ID: 7242878

Claim:
An image forming apparatus, comprising: a developing device for developing an electrostatic latent image, formed on an image-bearing member, with toner; a developer supply container which contains developer containing toner and a carrier and is detachably mountable to a container mounting portion provided to a main assembly of said image forming apparatus, wherein one of a plurality of kinds of developer supply containers containing developers having different carrier ratios in the developers is selectively mountable to said developer mounting portion; developer supply means for supplying the developer contained in the developer supply container to said developing device; a developer discharge opening provided to said developing device, for causing an excessive portion of developer in said developing device to overflow into an outside of said developing device by supplying the developer to said developing device; carrier deterioration information detecting means for detecting information on deterioration of the carrier contained in the developer in said developing device; and notification means for providing notification of the kind of the developer supply container to be selected on the basis of the information on deterioration of the carrier when the developer supply container is replaced.