A configuration in which an opening is covered with a plurality of partition members is provided, and timings of causing the partition members to move are differentiated, so that torque is reduced.

A developing cartridge is disposed in an image forming apparatus. The developing cartridge includes a developing portion; a toner storing portion; a partition wall positioned between the developing portion and the toner storing portion and provided with a toner supply section; a first agitating member inside the developing portion; and a second agitating member inside the toner storing portion, wherein at least one of the first agitating member and the second agitating member comprises an elastic member to be in contact with the partition wall.

A fixing portion 18c for suppressing movement of a developer bag 16 when the developer bag 16 is unsealed by moving a sealing member 19 is provided. By this, unsealing becomes easy.

Provided is a developer container, including: a frame body having an opening; a sealing member configured to seal the opening; an unsealing member configured to unseal the opening by moving the sealing member and accommodated inside the frame body; and a part of the sealing member peelably bonded to an outer peripheral edge of the opening on an opposite side of the unsealing member with respect to the opening.

This invention provides a developing apparatus including: first and second chambers containing developer and configured to form a circulation path of the developer; a first feeding member arranged in the first chamber and feeding the developer in a first direction; a second feeding member arranged in the second chamber and feeding the developer in a second direction opposite to the first direction; first and second communication parts through which the developer is transferred; a feeding path having a discharging port and communicating with the first chamber on a downstream side relative to the first communication part in the first direction to feed the developer toward the discharging port; a sealing part sealing the developer; a feeding path sealing part sealing the feeding path on an upstream side relative to the discharging port in the first direction; and an unsealing mechanism receiving a driving force and unsealing the sealing part.

The disclosed structure includes a belt-shaped conveying member configured to convey developer. The conveying member includes a partitioning portion, which is a partition for developer contained in a casing with respect to a conveying direction in which the developer is conveyed, wherein, when the developer container is new, a first developer amount which is an amount of the developer contained at an upstream side that is upstream of the partitioning portion in the conveying direction, is larger than a second developer amount which is an amount of the developer contained at a downstream side that is downstream of the partitioning portion in the conveying direction.

A developer accommodating container for accommodating a developer includes: a toner seal member for unsealably sealing an opening of the developer accommodating container; an unsealing member, connected to an end portion of the toner seal member, for unsealing the opening by moving at least a part of the toner seal member; and an auxiliary unsealing member for assisting unsealing by changing a pulling direction of the toner seal member by the unsealing member. The auxiliary unsealing member includes a shaft portion or a projected portion. The shaft portion or the projected portion extends in a longitudinal direction of the developer accommodating container.

A developing apparatus for developing an electrostatic latent image formed on an image bearing member includes a developer carrying member, first and second accommodation chambers to accommodate developer, and a feeding screw provided in the first accommodation chamber to feed the developer. In addition, a developer accommodation portion accommodates the developer to be supplied to the first accommodation chamber and is sealed by a sealing member. A controller executes an operation in a mode in which after the developer accommodating portion starts to be unsealed at the sealing member, the feeding screw is initially rotated for a predetermined period in a direction opposite to a normal direction in which the feeding screw is rotated during the image forming operation, and after elapse of the predetermined period, the feeding screw is rotated in the normal direction.

A fixing portion 18c for suppressing movement of a developer bag 16 when the developer bag 16 is unsealed by moving a sealing member 19 is provided. By this, unsealing becomes easy.

A developer accommodating unit for accommodating a developer for image formation includes a flexible container provided with an opening 35a for permitting discharge of the developer, a frame for accommodating the flexible container and for accommodating the developer to be discharged from the flexible container, and an urging member 21 for urging a developer accommodating bag toward the frame for accommodating the developer accommodating bag 16. By this, it is possible to satisfactorily effect discharge of the developer from the flexible developer accommodating bag 16.