Abstract: An electrophotographic image forming apparatus which forms an image on a recording medium and to which a process cartridge can detachably be mounted includes (a) a cartridge mounting portion capable of detachably mounting a process cartridge including an electrophotographic photosensitive drum, a process device acting on the photosensitive drum, and a projection having a first-twisted-polygonal prism shape provided on one longitudinal end of the photosensitive drum, (b) a rotatable rotary member having a first twisted hole of polygonal cross-section, (c) a rotatable coupling shaft supported for axial movement and being provided at its one end with a second-twisted-polygonal prism shape fitted into the first twisted hole of the rotary member, and being provided at its other end with a second twisted hole of polygonal cross-section for engaging with and disengaging from the projection having the first-twisted-polygonal prism shape and having substantially the same twisted angle and twisted direction as those of

Abstract: The disclosure describes plastic formed products comprising:one selected from the group consisting of a thermoplastic resin and a thermosetting resin; and0.1 to 10 wt % of at least one selected from the group consisting of ferric oxide hydroxide particles, hematite particles, magnetite particles and maghemite particles;wherein (1) the average major axial diameter or the plate diameter of said ferric oxide hydroxide particles is 0.02 or 2.0 .mu.m and the average aspect ratio or the plate ratio thereof is 2 to 20, (2) the average particle size of said hematite particles, magnetite particles and maghemite particles is 0.01 to 1.0, the BET specific surface area thereof is 1 to 120 m.sup.2 /g and the water content on the surfaces thereof is not less than 0.02 wt %/m.sup.2 /g.

Abstract: The disclosure describes plastic formed products comprising:one selected from the group consisting of a thermoplastic resin and a thermosetting resin; and0.1 to 10 wt % of at least one selected from the group consisting of ferric oxide hydroxide particles, hematite particles, magnetite particles and maghemite particles;wherein (1) the average major axial diameter or the plate diameter of said ferric oxide hydroxide particles is 0.02 or 2.0 .mu.m and the average aspect ratio or the plate ratio thereof is 2 to 20, (2) the average particle size of said hematite particles, magnetite particles and maghemite particles is 0.01 to 1.0, the BET specific surface area thereof is 1 to 120 m.sup.2 /g and the water content on the surfaces thereof is not less than 0.02 wt %/m.sup.2 /g.

Abstract: An original-reading device includes a light source for irradiating an original disposed at a reading position, a photoelectric conversion device for converting light reflected from the original into an image signal, a reading unit supporting the light source and the photoelectric conversion device, a feeder for feeding the original to the reading position, a reference member provided at a position different from the reading position, for correcting an image signal from the original, and means for moving the reading unit between a position for reading the reference member and the reading position.

Abstract: An image reading apparatus comprising: a motor and power transmission belt for feeding a recording medium on which image information is recorded; a photoelectric transducer for reading the image information as image data; two buffers for storing therein the image data read by the transducer and out of which the image data is read, the storing and reading of the image data being performed alternately; and a CPU for controlling the motor and belt, the transducer, and the two buffers; characterized by either a buffer or a gate for preventing a delay in the transfer of the image data due to a delay in the response of the motor and belt.

Abstract: The light from an original is reflected by first, second and third mirrors in succession. The light from the third mirror is imaged on an image sensor by a lens. The second mirror, as compared with the first and third mirrors, is disposed far from an original illuminating light source. The optical path among the first, second and third mirrors and the lens is a zigzag.