Abstract: A developer supply member according to an embodiment may be configured such that in a case where a developer supply member is rotated at a circumferential speed of 136.1 mm/sec while an abrasive film including a grain size of 30 ?m fixed on a stainless steel indenter including a surface in a shape of a 50 mm squire and a thickness of 10 mm is pressed into an elastic layer of the developer supply member by 0.73 mm, an amount of decrease in an outer diameter of the developer supply member, obtained by subtracting a value of the outer diameter of the developer supply member when the indenter is separated from the developer supply member 250 seconds after the pressed-into amount of the indenter reaches 0.73 mm from a value of the outer diameter of the developer supply member before the indenter is pressed into, is 0.03 mm or less.

Abstract: A developer supply member according to an embodiment may be configured such that in a case where a developer supply member is rotated at a circumferential speed of 136.1 mm/sec while an abrasive film including a grain size of 30 ?m fixed on a stainless steel indenter including a surface in a shape of a 50 mm squire and a thickness of 10 mm is pressed into an elastic layer of the developer supply member by 0.73 mm, an amount of decrease in an outer diameter of the developer supply member, obtained by subtracting a value of the outer diameter of the developer supply member when the indenter is separated from the developer supply member 250 seconds after the pressed-into amount of the indenter reaches 0.73 mm from a value of the outer diameter of the developer supply member before the indenter is pressed into, is 0.03 mm or less.