A development device includes a developer bearing, a regulation portion, and a magnetic field generation member that is provided inside of the developer bearing member. The magnetic field generation member includes a development pole a first magnetic pole, and a second magnetic pole. The magnetic field generation member has a region satisfying |(Br(a)Br(c))/10|<0.3, wherein Br(a) is a magnetic flux density in a normal direction relative to the surface of the developer bearing member on a position shifted by 5 from a point nearest to the regulation portion on the developer bearing member around a center of the developer bearing member, and Br(c) is the magnetic flux density around the developer bearing member on a position shifted by +5 from the point nearest to the regulation portion on the developer bearing member.

A developing method in a developer device having a developing roller configured to rotate within a housing, the developing roller having a first portion that is exposed through an opening of the housing, a second portion at which developer attached to the developing roller separates from the developing roller and a third portion between the first and second portions, and an elastic sheet in contact with the developing roller between the second and third portions of the developing roller, the method includes guiding airflow along a first airflow passage, which is formed in the housing and partially facing the second portion of the developing roller, and guiding airflow along a second airflow passage facing the third portion of the developing roller and adjacent to the first airflow passage.

A developing device includes a development roller, a layer-thickness limiting member, and a first screw. The development roller includes a fixed magnet and a sleeve. The first screw supplies developer to the development roller while conveying the developer in a first conveyance direction. The sleeve includes a plurality of recesses. Each of the recesses has an elongated shape, and a downstream end and an upstream end in the first conveyance direction. The downstream end is located farther downstream in a rotational direction of the sleeve than the upstream end. When the developer in each of the recesses passes the layer-thickness limiting member, the developer moves upstream in the first conveyance direction.

A developing device, including: a developer containing toner and carrier; and developer bearer configured to have surface thereof bear the developer and endlessly move, and to develop latent image over surface of latent image bearer by supplying toner in developer to latent image in developing region facing the latent image bearer, wherein carrier contains fine particles, value X in volume resistivity R (=10.sup.X) (?.Math.cm) of carrier is 11.5-16.0, developer bearer includes: magnetic field generating unit including a plurality of magnetic poles; and developing sleeve having a cylindrical shape enclosing magnetic field generating unit, and configured to bear developer over outer circumferential surface of cylindrical shape by magnetic force of the magnetic field generating unit and perform surface moving by rotating relative to developing device body, and developing device includes developing sleeve voltage applying unit configured to apply AC component-containing voltage to developing sleeve.

A developing device includes a magnet roller, a developing sleeve that revolves in a predetermined direction of revolution around the magnet roller, a developer tank having an opening that forms a development region by opening a part of a surface of the developing sleeve in a circumferential direction, a regulating member that regulates a layer thickness of a developer on the surface of the developing sleeve, and a toner residue reduction member that reduces a residue of a toner adhering directly to the surface of the developing sleeve.

A developing device includes a developing roller which includes: a magnet roller having a plurality of magnetic poles in a circumferential direction; and a developing sleeve rotatably supported along an outer peripheral surface of the magnet roller, and which is configured to supply a toner to an image bearing member. The magnet roller is configured so that the relative position thereof to the developing sleeve is changeable.

An interface receives a first digital signature of real-world data. A memory stores the first digital signature as seed data. The interface receives a second digital signature of real-world data. The memory stores the second digital signature as seed data. A processor generates first draw seed based, at least in part, on the seed data. The processor generates a first draw result based upon the first draw seed and a drawing algorithm. The interface receives a second draw result from a remote entity, the second draw result based, at least in part, on the first digital signature and the second digital signature. The processor determines whether the first draw result and the second draw result are in agreement. Upon a determination that the first draw result and the second draw result are in agreement, the interface communicates at least one of the first draw result and the second draw result.

A developing device includes a developing container, a rotatable developing member to carry and feed the developer to a developing position, a magnet provided non rotatably and stationarily inside the rotatable developing member and provided with a regulating pole, and a regulating portion to regulate an amount of the developer carried on the rotatable developing member by a magnetic force of the regulating pole. With respect to a rotational direction of the rotatable developing member, a local minimum position, where a magnetic flux density of the regulating pole in a normal direction is a local minimum value, is downstream of a first local maximum position where the magnetic flux density of the regulating pole in the normal direction is a first local maximum value, and is upstream of a second local maximum position where the magnetic flux density of the regulating pole is a second local maximum value.

A developing device includes a developing sleeve configured to carry and convey developer containing non-magnetic toner and magnetic carrier and having a plurality of concave parts on a surface thereof. The concave parts are periodically arranged in each of a rotation direction and a width direction of the developing sleeve, and each have a shape that can house a circular shape having a diameter equal to an average particle diameter of the carrier carried on the developing sleeve, in a planar view. A distance between the concave parts is smaller than the average particle diameter.

An object of the present invention is to provide a carrier in which decrease in specific gravity is achieved and a volatile organic compound (VOC) is reduced and to provide an electrophotographic developer using the carrier. There is provided a carrier including a core material coated with a resin, the core material including a magnetic component and a nonmagnetic component, wherein the sum total of volatile organic compounds is 1 ppb or more and 1.5 ppm or less. There is also provided an electrophotographic developer using the carrier.