A developing device includes a frame, a cylindrical developer carrying member rotatably supported by the frame and configured to carry a developer containing toner particles, and a regulating member fixed to the frame at one end thereof and including a contact portion which contacts the developer carrying member at the other end of the regulating member and which forms a contact nip between the regulating member and the developer carrying member. When a position of the contact portion where a maximum of a pressure distribution of the contact portion to the developer carrying member with respect to a rotational direction of the developer carrying member is indicated is a reference position, the contact portion includes a first surface portion positioned upstream of the reference position and a second surface portion positioned downstream of the reference position with respect to the rotational direction.

A developing device includes a development casing, a developer carrying member, a regulating blade, a pair of pressing members, and a blade seal member. The development casing has an opening part. The developer carrying member has a developing area. The blade seal member includes a first layer material and a second layer material. The development casing has facing surfaces. The second layer material has positioning protrusions protruding from the first layer material in a rotation axis direction at positions inside both ends of the first layer material in the rotation axis direction, so as to contact the facing surfaces and be positioned in the rotation axis direction. When the second layer material is positioned in the rotation axis direction, the first layer material is pressed in contact with the pressing members in the rotation axis direction.

An image forming apparatus includes a developing case housing a developer. A doctor blade is separated from an outer surface of a developing sleeve, the both ends of the doctor blade in a longitudinal direction are fixed to a developing case, and the doctor blade includes a through hole in the central portion in the longitudinal direction. An adjusting portion adjusts the distance between the doctor blade and the outer surface of the developing sleeve. A rotating portion is provided on one surface of the base portion, inserts the through hole, and rotates with respect to the doctor blade and the developing case.

Provided is an electrophotographic member including an electro-conductive substrate and a surface layer on the substrate. The surface layer contains a urethane resin and a first polymer having a specific nitrogen-containing structure. The urethane resin has a structure derived from a second polymer containing a fluorine atom or a structure derived from a third polymer containing a fluorine atom and a silicon atom. The surface layer contains nitrogen atoms derived from the nitrogen-containing structure at a specific ratio in a region from the outer surface of the surface layer to a depth of 300 nm, and the atomic ratios of nitrogen atoms, fluorine atoms, and silicon atoms in a region from a depth of 100 nm from the outer surface of the surface layer to a depth of 300 nm and a region from the outer surface to a depth of 10 nm have specific relationships.

A developing device includes a developing roller, a toner supply roller, a regulating blade, a casing, and a cleaning member. The developing roller supplies a toner to the image carrier in a region opposed to an image carrier. The toner supply roller is located opposed to the developing roller. The toner supply roller forms a magnetic brush made of a two-component developer including a magnetic carrier and a toner on an outer peripheral surface to supply a toner to the developing roller in a region opposed to the developing roller. The regulating blade is located opposed to the toner supply roller at a predetermined interval. The casing houses the developing roller, the toner supply roller, and the regulating blade. The cleaning member reciprocates along a longitudinal direction of the regulating blade so as to remove a toner accumulated on a top surface of the regulating blade.

A developing device includes a frame, a cylindrical developer carrying member rotatably supported by the frame and configured to carry a developer containing toner particles, and a regulating member fixed to the frame at one end thereof and including a contact portion which contacts the developer carrying member at the other end of the regulating member and which forms a contact nip between the regulating member and the developer carrying member. When a position of the contact portion where a maximum of a pressure distribution of the contact portion to the developer carrying member with respect to a rotational direction of the developer carrying member is indicated is a reference position, the contact portion includes a first surface portion positioned upstream of the reference position and a second surface portion positioned downstream of the reference position with respect to the rotational direction.

A developing device includes a developer container configured to contain a developer, a developing carrying member configured to carry and feed the developer to a developing position, and a regulating member configured to regulate an amount of the developer carried by the developer carrying member, wherein the developer carrying member includes a magnet provided non-rotatably and stationarily inside the developer carrying member, and wherein the developer carrying member is provided with information regarding magnetic flux density of the magnet.

The developing device includes a development container, a developer carrier, and a restricting blade. The development container has an opening. The developer carrier has a development area. The development container includes a pair of side frames, and a pair of side wall portions. In each of the pair of side wall portions, a seal member insertion hole extending through in the rotation-axial direction is formed at a position facing an end edge of the restricting blade in the rotation-axial direction. The developing device includes a blade-side side seal inserted in the seal member insertion hole to block a gap between the restricting blade and the side wall portion.

A restricting member includes a blade portion and a supporting portion. A contact portion is provided at the blade portion, and, in a cross section orthogonal to a longitudinal direction, the contact portion includes a first portion extending in a first direction and a second portion extending toward a free end from an end of the first portion and extending in a second direction. When a region demarcated by connecting an intersection point, the end of the first portion, and an end of the second portion by a straight line is defined as a first region, the intersection point being where an imaginary line intersects an extension line of the first portion in the first direction, an area of the first region is smaller on a longitudinal end portion than on a longitudinal central portion of the blade portion.

An image forming device includes photoconductor drum that rotates around axis and has drum circumferential face on which electrostatic latent image is formed, and developing unit that supplies developer to photoconductor drum thereby to manifest electrostatic latent image into developer image. The developing unit includes developing housing, developing roller supported by developing housing to be rotatable around axis, has first circumferential face that faces drum circumferential face and carries developer, and supplies carried developer to drum circumferential face, and restricting blade that contacts first circumferential face, and restricts amount of developer to be carried on first circumferential face, and first circumferential face has value of 4.5% to 10% as actual contact area ratio representing actual contact area relative to apparent contact area with restricting blade, and restricting blade is arranged relative to first circumferential face at contact linear pressure of 10 N/m to 60 N/m at actual contact area ratio.