A roller shaft is inserted into a mold including molding members respectively having a first mold surface that defines an outer circumference of a roller portion and second and third mold surfaces that respectively define first and second flat portions of the roller portion, and the mold is then closed. A molding material is injected around the roller shaft to integrally mold the roller portion. The roller portion includes the outer circumference and the first and second flat portions rising from the roller shaft to the outer circumference. The roller shaft includes flange portions at portions corresponding to the first and second flat portions. The flange portions prevent the molding material from leaking outside the first and second flat portions when the roller portion is integrally molded around the roller shaft by injection molding.

Provided is a conductive roller in which the occurrence of an image defect caused by a pressure mark is suppressed. In this conductive roller, plural resin layers are arranged on the outer circumference of a shaft 4. The resin layers include at least a base layer 1 and a surface layer 3 from the inner circumferential side. The plural resin layers all have a loss tangent (tan ) of 0.2 or less at a temperature of 40 C. and, among the plural resin layers, at least a pair of two adjacent layers satisfy a relationship of GoGi between the elastic modulus Go of a layer positioned on the outer circumferential side and the elastic modulus Gi of a layer positioned on the inner circumferential side.

A roller shaft is inserted into a mold including molding members respectively having a first mold surface that defines an outer circumference of a roller portion and second and third mold surfaces that respectively define first and second flat portions of the roller portion, and the mold is then closed. A molding material is injected around the roller shaft to integrally mold the roller portion. The roller portion includes the outer circumference and the first and second flat portions rising from the roller shaft to the outer circumference. The roller shaft includes flange portions at portions corresponding to the first and second flat portions. The flange portions prevent the molding material from leaking outside the first and second flat portions when the roller portion is integrally molded around the roller shaft by injection molding.

A shaping roll for melt extrusion molding used for melt extrusion molding of thermoplastic resin, the shaping roll for melt extrusion molding comprises a metal roll body, a first cylinder, and a second cylinder. The metal roll body has a heat medium passage internally. The first cylinder covers a surface of a middle portion of the roll body part. The second cylinder covers surfaces of both end portions of the roll body part. The first cylinder comprises a first metal material having a thermal conductivity of 40 W/m.Math.K or more. The second cylinder comprises a second metal material having a thermal conductivity of 20 W/m.Math.K or less. The first cylinder and the second cylinder are at least partially joined to each other.

A method for forming a roll core for use in an electrophotographic image forming device according to one example embodiment includes shaping the roll core from a mixture of an uncured elastomer and hollow microparticles. The elastomer of the shaped roll core is cured without permanently expanding hollow microparticles positioned near the outer surface of the shaped roll core. After curing, the hollow microparticles positioned near the outer surface of the shaped roll core are permanently expanded to form the roll core having compressible and resiliently recoverable hollow microparticles extending beyond an outer circumference of the roll core and providing a surface texture to the roll core.

A toner conveyance roller for an image forming apparatus including a toner image forming mechanism including a developing roller and the toner conveyance roller which is arranged opposite to the developing roller and used for supplying and scraping toner, wherein the toner conveyance roller has a roller part and a shaft part, the roller part includes a substantially cylindrical elastic layer composed of an elastic foaming body on a surface of the roller part, and a density of the elastic layer is higher in a longitudinal center part of the roller part than in both longitudinal end parts thereof, and a method for manufacturing the toner conveyance roller including a step of heat-pressing the crown-shaped elastic foaming body, and thereby, forming the elastic layer.

Provided is a technique for manufacturing a toner supply roller in which the toner conveying performance and the scraping performance of unneeded toner are excellent as well as the above-mentioned problems in molding can be resolved. Also provided is a method for manufacturing a toner supply roller including: an insertion process in which a roller member 10 comprising a shaft 11 and an elastic layer 12 composed of a foam having a columnar shape supported on the outer periphery of the shaft is inserted into a cylindrical forming tool m having on the inner peripheral surface irregular concaves and convexes or a recessed groove along the longitudinal direction; a transfer process in which the roller member inserted into the cylindrical forming tool is heated and the irregular concaves and convexes or the recessed groove along the longitudinal direction on the inner peripheral surface of the cylindrical forming tool are transferred on the surface of the roller member; and a releasing process in which the roller member on the surface of which the irregular concaves and convexes or the recessed groove along the longitudinal direction are transferred is taken out from the cylindrical forming tool to obtain a roller.

A shaping roll for melt extrusion molding used for melt extrusion molding of thermoplastic resin, the shaping roll for melt extrusion molding comprises a metal roll body, a first cylinder, and a second cylinder. The metal roll body has a heat medium passage internally. The first cylinder covers a surface of a middle portion of the roll body part. The second cylinder covers surfaces of both end portions of the roll body part. The first cylinder comprises a first metal material having a thermal conductivity of 40 W/m.Math.K or more. The second cylinder comprises a second metal material having a thermal conductivity of 20 W/m.Math.K or less. The first cylinder and the second cylinder are at least partially joined to each other.

Methods of making composite drive shafts and manufacturing assemblies thereof are provided. The methods include providing a removable mandrel having a cylindrical shape and assembling a lobe joint member at an end thereof. The lobe joint member includes at least three lobes equally distributed thereabout. A removable end flange is assembled to the lobe joint member at an opposite end of the lobe joint member from the removable mandrel to form a manufacturing assembly. A composite material is applied to an exterior surface of the manufacturing assembly to form a composite tubular that includes the lobe joint member at an end thereof. The removable end flange is removed from the lobe joint member and the removable mandrel is removed from within the composite tubular to form a composite drive shaft comprising the composite tubular and the lobe joint member integrally formed at an end of the composite tubular.

A toner supply roller is provided which has the most uniform and greatest possible foam cell diameters and a lower hardness particularly even in a lower-temperature and lower-humidity environment as compared with the conventional art and is less liable to suffer from imaging failure such as uneven density and white streaks. An image forming apparatus employing the toner supply roller is also provided. The toner supply roller (1) is produced by preparing a rubber composition which contains a rubber component including an epichlorohydrin rubber and an acrylonitrile butadiene rubber, an electrically conductive carbon black, a crosslinking component and a foaming component and, while extruding the rubber composition into a tubular body, continuously foaming and crosslinking the rubber composition of the tubular body by a continuous crosslinking apparatus including a microwave crosslinking device and a hot air crosslinking device. The image forming apparatus incorporates the toner supply roller (1).