Developing cartridge having a sheet member provided at end portion of a developing roller

A developing cartridge mountable on an image forming apparatus, the developing cartridge comprising:

• a frame provided with an accommodating portion configured to accommodate toner and an opening portion in fluid communication with the accommodating portion;
• a developing roller supported by the frame, opposing the opening portion and configured to rotate about a rotational axis while carrying the toner;
• a supplying roller in contact with the developing roller and configured to supply the toner from the accommodating portion to the developing roller;
• a stirring member configured to stir the toner in the accommodating portion and supply the toner to the supplying roller;
• a regulating member including a contacting portion in contact with the developing roller and a support portion supported by the frame, the regulating member being configured to regulate a thickness of a layer of the toner carried on a surface of the developing roller;
• and
• a sheet member provided only at an end portion of the developing cartridge in a direction of the rotational axis of the developing roller,
• wherein, in a state in which the developing cartridge is oriented in a direction in which the developing cartridge is mounted on an image forming apparatus, (i) the frame includes a bottom surface forming a part of the accommodating portion and a wall portion extending upward from the bottom surface, (ii) the wall portion is provided at an end portion of the frame in a direction orthogonal to both the direction of the rotational axis of the developing roller and a direction of gravity, (iii) only one surface of the sheet member is attached to a surface of the wall portion, and (iv) as seen in the direction of the rotational axis, a line extending along and upward from the surface of wall portion does not cross the developing roller.