Provided is an electrophotographic member including: an electroconductive substrate; and an elastic layer on the substrate, the elastic layer constituted by a single layer, the elastic layer containing a silicone rubber having a dimethylsiloxane structure, wherein when a peak top temperature of an ion thermogram derived from the dimethylsiloxane structure, the ion thermogram being measured from a first sample sampled from a first region having a thickness of 0.5 m from a first surface of the elastic layer toward a second surface thereof, is represented by T1, and a peak top temperature of an ion thermogram derived from the dimethylsiloxane structure, the ion thermogram being measured from a second sample sampled from a second region corresponding to a thickness of 1.0 m to 1.5 m from the second surface toward the first surface, is represented by T2, T1 and T2 satisfy a relationship of T1>T2.

A magnet roller includes a shaft, a first magnet piece, and a second magnet piece. The first magnet piece and the second magnet piece are bonded to an outer circumference of the shaft with an adhesive. The first magnet piece has a first surface and a recessed portion. The recessed portion is recessed with respect to the first surface. The second magnet piece has a second surface and a convex portion. The second surface is held in contact with the first surface. The convex portion protrudes with respect to the second surface. The convex portion fits into the recessed portion.

A developing device includes a cylindrical developing roller, a regulation member, a magnetic member, and a synthetic resin member. The regulation member includes a first opposing surface facing an outer circumferential surface of the developing roller. The magnetic member is arranged on a side surface of the regulation member. The synthetic resin member is arranged on a side surface of the magnetic member. The synthetic member includes a second opposing surface facing the outer circumferential surface of the developing roller. The second opposing surface is tilted at 40 or more but 60 or less with respect to the first opposing surface to be increasingly distant from the outer circumferential surface of the developing roller toward an upstream side in a rotating direction of the developing roller. A solubility parameter of a material of the synthetic resin member is 23 (J/cm.sup.3).sup.1/2 or more. Magnetic toner contains toner and resin fine particles.

A developing apparatus including: a toner having a toner particle and an external additive; a toner carrying member used for carrying the toner; and a charging member used for injecting charge into the toner, in which the external additive includes a fine particle A and a fine particle B, the fine particle A is at least one fine particle selected from a group consisting of a silica fine particle and a silicone fine particle, the fine particle B is a specific conductive fine particle, the toner carrying member is a developing roller having: a substrate having an outer surface having conductivity; and a resin layer on the outer surface of the substrate, and impedance of the outer surface of the developing roller and a maximum value of electric potential of the outer surface are in specific ranges.

A developer carrying member includes a shaft, a magnet, a sleeve, a flange, and adhesive. The flange has a first fitting portion, a second fitting portion, and a groove portion. The adhesive is disposed in the groove portion. A first groove portion and a second groove portion are formed continuously in this order from the first fitting portion side to the second fitting portion side. The height from the bottom surface of the second groove portion to the outer circumferential surface of the first fitting portion is greater than that from the bottom surface of the first groove portion to the outer circumferential surface of the first fitting portion.

A developer carrying member includes a shaft, a magnet, a sleeve, a flange, and adhesive. The height from the bottom surface of a second groove portion to the outer circumferential surface of a first fitting portion is greater than the height from the bottom surface of a first groove portion to the outer circumferential surface of the first fitting portion. The height from the bottom surface of a third groove portion to the outer circumferential surface of the first fitting portion is smaller than the height from the bottom surface of the second groove portion to the outer circumferential surface of the first fitting portion, and is equal to or greater than the height from the bottom surface of the first groove portion to the outer circumferential surface of the first fitting portion.