Abstract: A thermosensitive recording material comprising a matrix of an electrically insulating, film-forming thermoplastic resin and dispersed as a fine powder in the matrix, a linear aliphatic dicarboxylic acid having at least 13 carbon atoms or its ammonium salt, and a thermosensitive electrostatic recording material provided by applying aforesaid material to the conductive surface of a thermally stable substrate.

Abstract: A process of making a thermosensitive recording material comprising a matrix of an electrically insulating, film-forming thermoplastic resin and dispersed as a fine powder in the matrix, a linear aliphatic dicarboxylic acid having at least 13 carbon atoms or its ammonium salt, and a thermosensitive recording material provided by applying aforesaid material to the conductive surface of a thermally stable 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 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: 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 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: 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: An electric recording material comprising a support and an electrically conductive recording layer formed at least in the surface portion of the substrate, which recording layer is composed of a dispersion of a basic salt of divalent tin or tin (II) hydroxide in an electrically conductive medium, gives an image having high density and contrast at relatively low electric power when applied to an electrolytic recording process utilizing cathodic reduction. This image can be preserved for a long time without discoloration of the background. Especially good results are obtained when a specific polyhydric alcohol is incorporated in the recording layer optionally with a specific organic sulfur compound.

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 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: 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: 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.