Abstract: A transfer sheet on which toner images free of broadening of edge portions and having sharp contours can be transferred even in the electrophotography or electrostatic printing of the transfer type using conductive or semiconductive toners, i.e., magnetic toners, is disclosed. This transfer sheet is characterized in that a conductive or semiconductive toner-receiving face having a volume specific resistance of at least 3.times.10.sup.13 .OMEGA.-cm is formed on at least one surface of a substrate of the transfer sheet.

Abstract: An electrophotographic photosensitive material suitable for offset printing and lithography comprising a flexible substrate, an electroconductive back coat layer formed on one surface of the substrate, an electroconductive intermediate layer formed on the other surface of the substrate and a photoconductive layer formed on the intermediate layer, said photoconductive layer being composed of a fine powder of a photoconductor dispersed in an electrically insulating resin, wherein said intermediate layer is composed of a composition comprising (A) an acrylic resin, (B) a vinyl acetate polymer having a degree of polymerization of 100 to 1700 and (C) a resinous conducting agent, in said composition the weight ratio of acrylic resin (A)/vinyl acetate polymer (B) is in the range of 4/1 to 10/1 and the amount of the conducting agent (C) is 20 to 100 parts by weight per 100 parts by weight per 100 parts by weight of the sum of the components (A) and (B), said intermediate layer has such a multi-layer distribution stru

Abstract: A transfer sheet for electrostatically transferring thereon an electrically conductive or electrically semi-conductive toner in electrostatic photography or electrostatic printing, which comprises a substrate and a toner-receiving layer formed on at least one surface of the substrate, which toner-receiving layer contains a composition comprising (A) a thermoplastic acrylic polymer having a carboxyl group content of 2 to 30% by weight and (B) a thermosetting resin reactive with the acrylic polymer (A), and a process for preparing this transfer sheet by using an aqueous coating composition are disclosed. In this transfer sheet, the electric resistance can be maintained at a high level even under high humidity conditions, and a toner image can be transferred on this transfer sheet at a high transfer efficiency.

Abstract: A system for reducing or compressing band width of an image signal by logically combining each picture element on at least two scanning lines to form 0 and 1 sections, and coding the 0 and 1 sections for transmission. The coding step comprises run length-coding one of the 0 and 1 sections, and converting the other section into a series of raw signals with an end signal positioned at the end of the raw signals train for indicating the termination thereof.

Abstract: In the electric recording process comprising relatively moving a pair of a recording electrode and a counter electrode and an electrostatic recording material electrically connected between said two electrodes, applying an electric recording signal between said two electrodes to form an electrostatic image on the electrostatic recording material, developing the so formed electrostatic image with a developer and, if desired, fixing the developed image, when a high frequency signal formed by amplifying and modulating an image signal is applied as the electric recording signal and the electrostatic image formed on the electrostatic recording material is developed with an electroconductive powdery developer containing a fine powder of a magnetic material, high quality recorded images free of such troubles as blurring, tailing, fogging and Moire can be obtained even at high recording speeds.

Abstract: In the electrostatic recording process comprising relatively scanning a recording electrode on an electrostatic recording material which is electrically connected between said recording electrode and a counter electrode, applying a high frequency alternating current or asymmetric alternating recording signal formed by amplifying and modulating an image signal by a high frequency carrier wave between said two electrodes to form an electrostatic image on the electrostatic recording material, developing the so formed electrostatic image with a developer and, if desired, fixing the developed image, when a specific dielectric layer is selected to the kind of the recording signal and the electrostatic image formed on the dielectric layer is developed with an electroconductive powdery developer containing a fine powder of a magnetic material, high quality recorded images free of such problems as blurring, tailing, fogging and Moire can be obtained a high recording efficiency.

Abstract: In the electrostatic recording process comprising relatively scanning a recording electrode on an electrostatic recording material electrically connected between said recording electrode and a counter electrode, applying a high frequency alternating current or asymmetric alternating current recording signal formed by amplifying and modulating an image signal by a high frequency carrier wave between said two electrodes to form an electrostatic image on the electrostatic recording material, developing the so formed electrostatic image with a developer and, if desired, fixing the developed image, when an electrostatic recording material including an electroconductive substrate having a specific multi-layer distribution structure is used and if a dielectric layer is disposed on this electroconductive substrate in a specific arrangement selected according to the kind of the recording signal to be applied, such problems as blurring, tailing and fogging can be effectively eliminated and recorded images excellent in

Abstract: An electrostatic photographic copying machine includes a photosensitive body having a photosensitive layer on its surface, a charging apparatus, a developing device and a transfer device arranged along a moving passage of the photosensitive body. An optical system projects an image of an original onto the surface of the charged photosensitive body, and a fixation apparatus fixes a transferred image onto copying paper.

Abstract: An apparatus for developing an electrostatic latent image formed on the surface of an electrostatic latent image-bearing material by applying a powdery developer, wherein means are provided for bringing the surface of a developer-retaining member retaining a layer of the powdery developer thereon into rolling contact with the surface of the image-bearing material in such a relation that a reservoir zone of the developer is formed at least upstream of the zone of rolling contact between the two surfaces, and means are provided for physically disturbing the developer in the reservoir zone to cause the developer to make an irregular motion.

Abstract: A process for preparing a photosensitive material for electrostatic photography having an improved memory resistance, which comprises a photoconductive layer on an electrically conductive substrate, the photoconductive layer comprising (1) a finely divided inorganic photoconductor, (2) 5 to 50 parts by weight, per 100 parts by weight of the photoconductor of an electrically insulating organic synthetic resin binder having a specific resistance of at least 10.sup.14 ohm-cm, and (3) 0.001 to 1 % by weight, based on the photoconductor, of at least one photo-memory erasing compound selected from alkali metal dichromates, which process comprises forming the photoconductive layer by applying a coating composition to the electrically conductive substrate at a coating weight of 5 to 50 g/m.sup.

Abstract: A magnetic toner for electrostatic photography consisting essentially of spherical particles of a composition comprising a fine powder of a magnetic material having an average particle size not exceeding 1000 m.mu. and being dispersed in a binder resin, said powdery magnetic material being present in an amount of 25 to 75% by weight based on the composition, spherical particles of said composition having such a particle size distribution that particles having a particle size larger than 44 .mu. occupy up to 10% of the total particles and particles having a particle size smaller than 2 .mu. occupy up to 10% of the total particles, wherein said fine powder of the magnetic material is distributed predominantly in the surface layer portion of each spherical particle and said spherical particles have a volume resistivity not higher than 1 .times. 10.sup.11 .OMEGA.-cm as measured in a magnetic field of about 680 gauss under a voltage of 1000 V.

Abstract: A corona discharge device including a corona discharge electrode, an opposing electrode disposed opposite to the corona discharge electrode, a high voltage alternate current source electrically connected between the two electrodes, and a grid provided in a corona discharge current flow path between the two electrodes. The grid is grounded through a nonlinear bias element.

Abstract: A developer for electrostatic photography comprising as indispensable components a fine powder of a magnetic material and a binder resin, said developer consisting essentially of a dry blend of (A) substantially spherical particles of a composition comprising a medium of said binder resin and said fine powder dispersed in the binder resin medium and (B) a finely divided solid conducting agent having a particle size smaller than 1/10 of the size of the spherical particles (A), said spherical particles (A) having a crater-like rough surface, said finely divided solid conducting agent (B) being stuck to said spherical particles (A) through said crater-like rough surfaces thereof, and the volume resistivity of said dry blend being not higher than 1 .times. 10.sup.11 .OMEGA.-cm.

Abstract: A liquid developer comprising a dispersion of a dye or pigment having a long chain alkyl group in their molecular structure in a liquid hydrocarbon. The liquid developer for electrophotography is excellent in dispersibility of the image-forming dye or pigment particles, uniformity in charge polarity, storage stability, distinct-image forming ability and image-fixing property, and such liquid developer can be prepared without aid of conventional modifiers such as control agents dispersing agents, and fixing agents.

Abstract: An electric recording process comprising applying electricity to an anode of a solid electrolyte, said electrolyte being a Group IB metal compound having an ionic conductivity of at least 1 .times. 10.sup..sup.-4 .OMEGA..sup..sup.-1 cm.sup..sup.-1 under application conditions. Said anode is contacted with a recording layer containing color forming agent capable of reacting with ions of said metal of Group IB of the Periodic Table to form a visible image.

Abstract: An electrostatic photographic copying apparatus includes an optical system for projecting an image of an original onto the surface of a photosensitive drum. The system consists of openings for exposure of the original and the photosensitive drum, first and second reflex mirrors, and a mirror lens. The mirror lens is disposed so that light from the original is reflected by the first reflex mirror into said mirror lens and from the mirror lens back to the first reflex mirror. The light from the original is then reflected by the first reflex mirror to the second reflex mirror and from the second reflex mirror onto the photosensitive drum to thereby form a four-fold reverse image of the original being copied.

Abstract: Apparatus for preventing successive jamming of copy sheets in copying apparatus of the type including a forwarding mechanism for moving a copy sheet along a running path through a treatment zone for forming a visible image on the copy sheets and a copy sheet feeding mechanism, the successive jamming prevention apparatus including one or more detecting members disposed at detecting points in the running path so that at least one of the detecting members will contact a copy sheet at any position in the running path, a switch having normally closed contacts opened in response to contact of any of the detecting members with a copy sheet to prevent actuation of the copy sheet feeding mechanism and normally open contacts closed in response to contact of any of the detecting members with a copy sheet to provide an alarm signal.

Abstract: A paper feed device for a copying machine, in which paper jamming at the copying paper cutting mechanism is effectively prevented is provided. This paper feed device for a copying machine comprises a feed reel for supporting a copying paper wound thereon in a roll-like form, a paper feed roller intermittently driven and rotated to take out the copying paper from the feed reel, an introduction roller disposed on the introduction side of a transfer passage for delivering the copying paper to copying treatment zones in the copying machine, and a copying paper-cutting mechanism disposed between the paper feed roller and the introduction roller to cut the copying paper taken out of the feed reel into a prescribed length.

Abstract: A photosensitive drum-type electrostatic copying apparatus includes a size designating member disposed adjacent to the original to be copied. The size designating member is connected by a cable to a position adjusting member that is rotatably mounted coaxially with the drum. As the size designated member is moved, the position adjusting member is rotated to position a switch in correspondence to the desired length of the original to be copied and the transfer paper. The position of the switch determines the length of the transfer paper by activating a cutter when the desired length of the transfer paper is sensed by the switch.

Abstract: An electrostatic photographic copying apparatus wherein the image-forming device, the optical device, the transfer device and the transfer paper transferring device are controlled according to the rotation of the rotary drum so that one cycle of the copying operation is completed while the rotating drum, equipped with a photosensitive element on which to form an image, is rotated through two turns. Substantially the entire surface of the rotary drum can be utilized as an image-forming area by rotating the rotary drum through two turns in one cycle of the copying operation.