A developing device includes a developing container, a developer carrier, a seal member, and a pair of pressing members. The developing container has an opening. The seal member includes a contact end part that makes contact with an entire region of an outer circumferential surface of the developer carrier in its rotary shaft direction and is one of end edges of the seal member in a longitudinal direction thereof on a side near the developer carrier and an interposed end part that is interposed between each of both end parts of the developer carder and a corresponding one of the pressing members and is an end edge of the seal member orthogonal to the contact end part, and a chamfered shape is formed at a corner between the contact end part and the interposed end part.

A developer supply container detachably mountable to a developer receiving apparatus and settable in a developer receiving apparatus by a setting operation including at least a rotation toward a setting position, includes a containing portion for containing the developer; a rotatable discharging member for discharging the developer out of said containing portion; drive transmitting means, engageable with a driving gear provided in said developer receiving apparatus and rotatable in a direction opposite the setting direction, for transmitting a rotating force from said driving gear to said discharging member.

A toner case includes a case main body, a cover, and a seal member. The case main body is configured to contain a toner and to rotate. The cover is configured to cover an opening part arranged at the case main body and to maintain a rotation stop state when the case main body rotates. The seal member is interposed between the case main body and the cover and configured to maintain a rotation stop state when the case main body rotates. At least a part of the seal member is composed of an elastic material.

Provided are a process cartridge and an electrophotographic apparatus each of which is reduced in fogging for reducing a toner consumption. Specifically, provided is a process cartridge, which is removably mounted onto a main body of an electrophotographic apparatus, the process cartridge including: a developing unit containing a toner; and an electrophotographic photosensitive member, wherein the toner is a toner including a toner particle, and has a polyvalent acid metal salt on at least part of a surface of the toner particle, wherein the polyvalent acid metal salt includes at least one kind of metal element selected from metal elements belonging to from Group 3 to Group 13, and wherein a surface layer of the electrophotographic photosensitive member contains a resin including a siloxane segment.

A developer cartridge includes a developer container, a casing, a sealing member, and a drive input. The developer container is configured to sealingly contain developer therein. The developer container has an outlet through which the developer flows out of the developer container. The casing is configured to accommodate the developer container therein. The casing supports the developer container to allow the developer container to rotate about an axis thereof in a rotating direction. The sealing member is configured to seal the outlet. The drive input is configured to transmit rotational driving force to the developer container. The sealing member is fixed to the casing.

A cartridge includes a shutter that opens and closes when the cartridge is attached and detached to a developing unit or image forming apparatus. The cartridge includes a casing having a chamber with a first opening at one end portion allowing toner to flow out of the casing. The cartridge includes a cover that covers the first opening, movable with the casing and having a second opening allowing toner to flow out of the cover. The shutter is located at the one end portion and has a protrusion further from the one end portion than the cover. The developing unit supports the protrusion when the cartridge is mounted thereon, and the casing pivots with the cover relative to the developing unit between a first position where the shutter closes the second opening and a second position where a third opening of the shutter overlaps the second opening.

An image forming apparatus, having a photosensitive drum, a developing roller movable between a contacting position, in which the developing roller contacts the photosensitive drum, and a separated position, in which the developing roller is separated from the photosensitive drum, a moving mechanism to move the developing roller between the contacting position and the separated position, a fuser including a heating member and a pressing member to nip a sheet at a position between the heating member and the pressing member, a nipping-force adjuster to switch a nipping force in the fuser between a first nipping force and a second nipping force being greater than the first nipping force, a motor, and a driving-force transmitter to transmit a driving force from the motor to the developing roller, is provided. The driving-force transmitter transmits the driving force further to the moving mechanism and the nipping-force adjuster.

A developing cartridge including a casing, a developing roller, a developing roller gear, a gear cover, a first boss, and a pressure receiving surface. The developing roller is positioned closer to a first end portion of the casing than to a second end portion of the casing in a first direction. The first boss extends in a second direction and is movable together with the casing. The first boss is positioned away from the developing roller in the first direction by a first distance and also positioned away from the developing roller in a third direction. The pressure receiving surface is positioned further from the developing roller than the first boss is from the developing roller in the third direction. The pressure receiving surface is positioned away from the developing roller by the first distance or by a second distance shorter than the first distance.

A developer container includes: a case that stores developer and in which a developer outlet for discharging the developer is formed; a conveying spiral that is rotatably disposed in the case and rotates to convey the developer toward the developer outlet in an axial direction of the conveying spiral; a guide wall that is disposed along the conveying spiral and guides the developer in the axial direction of the conveying spiral; and a push member that is attached to the conveying spiral and rotates with the conveying spiral to push the developer into the developer outlet. A cutout is formed at a portion of the guide wall corresponding to the push member to form a guide portion that guides the developer to the developer outlet.

Provided is a developer replenishing container including: a developer containing part capable of containing a developer; a discharge port through which the developer contained in the developer containing part is discharged; a conveyance part conveying the developer in the developer containing part by rotating; and a displacement part displaceable in conjunction with rotation of the conveyance part in the developer in a vicinity of the discharge port, and including a moving member capable of reciprocating in conjunction with the rotation of the conveyance part and a biasing member which biases the moving member and which is expandable according to movement of the moving member.