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 roller for an electrophotographic image forming apparatus, which conveys a developer, wherein the developing roller includes a developing sleeve and a member that generates a magnetic flux inside the developing sleeve, and the developing sleeve contains an aluminum alloy containing more than 0.6% by mass of silicon.

A processor generates a first seed, wherein the first seed is a random number. The processor generates, a digital signature of the first seed. An interface communicates digital signature of the first seed to a first remote entity. The interface receives a digital signature of a second seed. After communicating the digital signature of the first seed to the first remote entity, the interface receives the second seed from the first remote entity. After receiving the digital signature of the second seed, the interface communicates the first seed to the first remote entity. The processor determines, using the digital signature of the second seed and the second seed, whether the second seed is valid. Upon a determination that the second seed is valid, the processor combines the first seed and the second seed to form a drawing seed. The processor generates a first draw result using the drawing seed and a drawing algorithm. The interface receives a second draw result from the first remote entity. The processor compares the first draw result and the second draw result. The processor communicates the draw results upon a determination that the first draw result and the second draw result are in agreement.

A developing sleeve includes first axially extending groove portions which satisfy D.sub.12R and W.sub.12R, where 2R is a volume-average particle size of a carrier, D.sub.1 is a maximum depth of each first groove portion and W.sub.1 is a width an opening of each first groove portion with respect to a circumferential direction of the developing sleeve, and second axially extending groove portions. Each second groove portion satisfies D.sub.2<2R, where 2R is the volume-average particle size of the carrier and D.sub.2 is a maximum depth of each second groove portion. Each or a plurality of the second groove portions are disposed between the first groove portions with respect to the circumferential direction of the developing sleeve.

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.

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 developer bearer, a developer regulator disposed opposite the developer bearer across a first gap, and an opposing member having an opposing face disposed opposing the developer bearer across a second gap wider than the first gap. The opposing face is disposed adjacent to and upstream from the developer regulator in a direction of rotation of the developer bearer. The opposing face is inclined relative to an orthogonal plane direction orthogonal to a side face of the developer regulator. The opposing face is inclined to progressively reduce a distance from the developer bearer to the opposing face in a direction of rotation of the developer bearer. A difference between the second gap and the first gap is not greater than 1.75 times as large as the first gap.

A development device includes: a developer carrier including a magnet roller and a sleeve around the magnet roller; and a restriction member provided opposed to the sleeve surface. When a region on the surface opposed to the restriction member is defined as a first region and regions adjacent to the first region are defined as second and third regions, a magnetic flux density is largest in the second region. When a position where the density is largest in the second region is defined as a reference position, a position where the density is a predetermined value in the second region is defined as a downstream position, and a position where the density is the predetermined value in the third region is defined as an upstream position, the width between the reference position and the upstream position is longer than the width between the reference position and the downstream position.

An image forming system includes, an electrostatic charge image developing toner; and a developing sleeve configured to convey the electrostatic charge image developing toner, wherein a toner particle included in the electrostatic charge image developing toner contains an amorphous polyester, the amorphous polyester is a polycondensate of a polyvalent carboxylic acid and a polyhydric alcohol, a content percentage of a structural unit derived from a bisphenol A derivative in the amorphous polyester is 10 mol % or less with respect to all structural units derived from the polyhydric alcohol, and the developing sleeve includes an aluminum alloy including more than 0.6% by mass of silicon.

A magnetic carrier according to the present invention includes a magnetic carrier core and a resin covering layer formed on a surface of the magnetic carrier core, wherein the resin covering layer contains a resin component and an inorganic fine particle, the inorganic fine particle contains an oxide of a typical metal element or a carbonate of a typical metal element, a moisture adsorption rate of the inorganic fine particle when allowed to stand in an environment of a temperature of 30 C. and a humidity of 80% for 72 hours is 25.0% by mass or less, an electrical conductivity of the inorganic fine particle is 2.010.sup.9 S/m or more and 2.510.sup.5 S/m or less, and a degree of crystallinity of the inorganic fine particle is 60% or less.