Unsaturated polyester resins and processes for making the same are disclosed herein. The bearing is simpler and economical to produce is also reliable and hardly subject to wear. As to the developing device for which the detection is effected before the developing operation therefor, the determining means determines the remainder from the information detected by the detector and the consumption amount deduced by the deducing means. Six of the seven segments are circular arc segments. The contact information may be a phone number or an e-mail address or a plurality of same.