Abstract: A transfer type electrostatic copying apparatus in which the area of a photosensitive member cleaned by a cleaning device reaches an exposure zone simultaneously or prior to the arrival of a movable portion of an optical system or an original carrier at an exposure starting position from a home position thereof. This results in clear and definite copied images being obtained. At the earlier stage at which the movable portion of the optical system or the original carrier starts moving, the photosensitive member is subjected to the cleaning process, and then the exposure process is effected when the movable portion or the original carrier is running stably. Thus, the electrostatic latent image obtained by the exposure are clear and definite and free from undesirable blurs. The photosensitive member is a rotary drum having bosses connected at opposite axial ends thereof which are removably mounted in holder members on the sidewalls of the copying apparatus.

Abstract: A magnetic brush developing device for an electrostatic copying apparatus wherein a magnetic brush is formed on a surface of a developing roller includes a magnet roller rotating inside of a cylindrical sleeve which is located adjacent to the surface of an electrostatic latent image retaining member to which a developing material is circumferentially applied. The magnet roller stops at a rotary angle such that a bristle of the magnetic brush on the sleeve is spaced from the surface of the electrostatic latent image retaining member, whereby a bristle of the magnetic brush is prevented from remaining in contact with the electrostatic latent image retaining member. Thereby, the developing material is prevented from causing the surface of the electrostatic latent image retaining member to change chemically, the developing material is prevented from causing the electrical characteristics of the surface to fail, and the developing material is prevented from adhering to the surface.

Abstract: A composite magnetic developer having a self-friction-chargeability is in the form of fixable magnetic particles having a particle size of 5 to 30 microns and comprising a finely divided magnetic material dispersed in a binder medium which shows an adhesiveness under application of heat and pressure, in which the fixable magnetic particles contain fine particles of a magnetic material embedded in the surface of the fixable magnetic particles in an amount of 1 to 10% by weight based on the fixable magnetic particles and fine particles of a magnetic material adhering to the surface of the fixable magnetic particles without being embedded therein in an amount of 1 to 20% by weight based on the fixable magnetic particles. This developer provides a sharp and clear transfer image having a high density without fogging or edge effects on a transfer sheet having a low electric resistance such as a plain paper.

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), is produced by coating on at least one surface of the substrate an aqueous composition containing the thermoplastic acrylic polymer in the form of an aqueous emulsion and the thermosetting resin in the form of an aqueous solution and drying the coated substrate to form a toner-receiving layer on the surface of the substrate.

Abstract: Disclosed is a heat-sensitive recording element comprising a recording layer including a starch partially esterified with an organic carboxylic acid as a polymeric binder for dispersing therein a leuco pigment and an organic acidic substance. This recording element provides a recorded image excellent in the water resistance and recording characteristics when it is used for thermographic recording. An aqueous solution of this partially esterified starch has a good storage stability and it does not get moldy even if it is stored for a long time.

Abstract: Disclosed is a method for preparing an original for projection by using a transfer film comprising a transparent plastic film substrate, an undercoating layer composed of an electrically conductive resin and having a surface resistance of 1.0.times.10.sup.6 to 9.0.times.10.sup.9 .OMEGA., and a toner receiving layer composed of a binder resin and having a surface resistance of 1.0.times.10.sup.10 to 1.0.times.10.sup.14 .OMEGA., which is formed on at least one surface of the transparent plastic film substrate through the undercoating layer.An original for projection which is excellent in the surface smoothness and image characteristics can be obtained by electrostatically transferring an image of a one-component type magnetic developer on a photosensitive plate for the electrostatic photography, onto the toner receiving layer of the above transfer film and bringing the transferred developer image into contact with a roller under application of a pressure to fix the developer image on the toner receiving layer.

Abstract: A fixing and heating device for an electrostatic copying apparatus includes a fixing roller which (a) remains stationary at least until a toner is softened, (b) is driven at a low speed to even the surface temperature of the fixing roller when the surface temperature is lower than a temperature suitable for fixing and when the surface temperature is equal to the temperature suitable for fixing except during a fixng operation, and (c) is driven at a speed suitable for fixing when the surface temperature is suitable for fixing during the fixing operation.

Abstract: Disclosed is an electrostatic photographic copying process comprising causing a substrate carrying an electrostatic latent image thereon to fall in contact with a magnetic brush of a one-component type magnetic developer to effect development of the electrostatic latent image and electrostatically transferring the formed image of the developer onto a transfer sheet, wherein a magnetic developer having an electrostatic capacity of 7.8 to 9.8 PF (picofarad) as determined under conditions of an electrode spacing of 0.65 mm, an electrode sectional area of 1.43 cm.sup.2 and an electrode load of 105 cm.sup.2 and a dielectric constant of 4 to 5 as determined under the above conditions is used as the one-component type magnetic developer.

Abstract: Disclosed is a one-component type magnetic developer which comprises a binder medium and 45 to 65% by weight, based on the total developer, of fine particles of a magnetic material dispersed in the binder medium, the binder medium comprising a homopolymer of an aromatic vinyl monomer or a copolymer of (a) at least one aromatic vinyl monomer with (b) at least one mono- or di-ethylenically unsaturated monomer other than the aromatic vinyl monomer and having a weight average molecular weight of 75,000 to 150,000, wherein the electrostatic capacity as determined under conditions of an electrode spacing of 0.65 mm, an electrode sectional area of 1.43 cm.sup.2 and an electrode load of 105 g/cm.sup.2 is 7.8 to 11.7 PF (picofarad), the dielectric constant is 4 to 6 as determined under the above conditions and the electric resistance is at least 5.times.10.sup.13 .OMEGA.-cm as determined under the above conditions.

Abstract: An electrostatic copying apparatus has a copying paper wound in a roll-like form, and an endless drive cable loop is wrapped about two drive reels rotated in one direction so as to cause part of an optical device or an original document carrier to travel reciprocally during a copying operation. Each copying operation mode, such as copying paper feeding, exposure, and copying paper cutting, is timed by means of mechanical constructions including a moving member to cause a paper feed detecting member, an exposure detecting member, a paper cut detecting member and a de-energization detecting member to pivot. These pivot motions result into a paper feed linkage actuation of a paper feed device, an exposure linkage energization of an exposure lamp, and a paper cut linkage actuation of a paper cut device.

Abstract: Disclosed is a composite magnetic developer which consists essentially of a homogeneous intimate mixture comprising a plurality of electrically insulating magnetic particulate developers comprising a binder medium and a finely divided magnetic material dispersed in the binder medium, in which the difference of the dielectric constant between the developers is in the range of from 0.2 to 0.85.This composite magnetic developer can provide a clear transferred image having a high density on a transfer sheet such as plain paper, and even if the copying operation is conducted continuously for a long time by using this developer, excellent transferred images can be obtained without substantial change of the composition of the composite developer or substantial reduction of the image density.

Abstract: A developer for electrostatic images comprising a binder medium and a pigment dispersed in the binder medium is disclosed. This binder medium comprises (A) a thermoplastic or rubbery polymer containing a member selected from the group consisting of a halogen atom and a nitrile group at a concentration of at least 100 milliequivalents per 100 g of the polymer and (B) a binder having a melting temperature lower than that of the polymer (A) at an (A)/(B) mixing weight ratio of from 1/20 to 1/1. The halogen- or nitrile-containing polymer (A) is present in the form of fine particles dispersed in the continuous phase of the binder (B). This developer has good flowability and charge characteristics at the developing step and shows an excellent offset-preventing effect at the fixing step.

Abstract: In a one-component type developer for electrophotography consisting essentially of a dry blend of fixing magneto-sensitive particles and flowability- and electric resistance-controlling fine particles, when an aromatic vinyl resin and/or an acrylic resin is used as a binder resin for the magneto-sensitive particles in combination with a low molecular weight olefin resin, the magneto-sensitive particles are much improved in the property of holding the flowability- and electric resistance-controlling fine particles on the surfaces thereof. Accordingly, these fine particles cannot be substantially separated from the magneto-sensitive particles under agitation conditions, development conditions and fixing conditions. As a result, contamination of the interior of a copying machine, especially an optical system, can be completely prevented, and also contamination of the background can be completely prevented.

Abstract: A developer for electrostatic photography consisting essentially of a dry blend of (A) substantially spherical fixing magneto-sensitive particles of a composition comprising a binder medium and a fine powder of a magnetic material dispersed in the binder medium, the substantially spherical particles (A) have on their surfaces fine convexities and concavities formed by spraying a dispersion of the composition into a drying atmosphere and have a particle size of 2 to 44 microns, and (B) flowability- and electric resistance-controlling fine particles having a volume resistivity not higher than 10.sup.12 .omega.-cm and a particle size not larger than 1/10 of the particle size of the substantially spherical particles (A). The fine particles (B) are distributed predominantly on the surface portion of said spherical particles (A). The mixing weight ratio of (A):(B) is in the range of from 1000:1 to 50:1.

Abstract: A method of controlling dew formation preventing heaters for a copying apparatus which includes a first temperature detecting means for detecting the temperature inside the copying apparatus, with a first reference temperature (T1) being set, a second temperature detecting means for detecting the temperature inside the copying apparatus, with a second reference temperature (T2) higher than said first reference temperature (T1) being set, a humidity detecting means for detecting the humidity inside the copying apparatus, with a reference humidity (H1) being set, and a first group of heaters and a second group of heaters to be controlled by said temperature detecting means and said humidity detecting means.

Abstract: A photographic process comprising exposing imagewise a photosensitive layer containing a divalent tin basic salt to actinic rays to form a pattern consisting of non-reducing exposed areas and reducing non-exposed areas and contacting the exposed photo-sensitive layer with a developer capable of forming or erasing color by reduction to thereby form a visible image corresponding to said non-exposed areas or said exposed areas.

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) 100 parts by weight of thermoplastic acrylic-styrene copolymer and (B) 10 to 100 parts by weight of dry method finely divided silica is 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 without broadening of contours of the image. This transfer sheet has feel and touch quite similar to those of ordinary paper and is very excellent in graphic characteristics.

Abstract: An electroconductive substrate for an electrically responsive recording material comprising a porous substrate and a layer of at least one cationic or anionic electric conductor, the conductor layer being formed in the porous substrate along the entire thickness direction thereof extending from one surface of the porous substrate to the other surface of the porous substrate, wherein the conductor layer has a multilayer distribution structure comprising (a) a layer of a cationic electroconductive resin distributed predominantly in the one surface portion of the porous substrate, (b) a layer of an anionic electroconductive resin distributed predominantly in the other surface portion of the porous substrate and (c) a layer of a polysalt of the cationic electroconductive resin and the anionic electroconductive resin interposed between both the electroconductive resin layers (a) and (b) in such a positional relationship that the polysalt layer (c) is adjacent to the electroconductive resin layers (a) and (b).

Abstract: A solid conducting agent comprising a finely divided inorganic solid acid and at least 0.5% by weight of a protonically conductive solid adsorbed and supported on the finely divided inorganic solid acid.This solid conducting agent is characterized by much reduced humidity dependency of the electric conductivity, and it has a sufficient electric conductivity even under low humidity conditions. An electro-responsive recording material including a layer of this solid conducting agent does not show a tacking phenomenon even under high humidity conditions.

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.