Abstract: A positively chargeable toner for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, etc. The toner contains a binder resin, a colorant or magnetic material, and a diorganotin borate. Because of the diorganotin borate contained, the toner has a uniform and stable triboelectric chargeability. The improved properties of the toner are enhanced when it is combined with positively chargeable fine silica powder.

Abstract: A motor drive amount correction signal generating circuit (14) corrects a deviation of an intermittent feed amount of a magnetic tape (1) by using reverse rotation pulse groups (t.sub.1, t.sub.2, t.sub.3, etc.) or forward rotation pulse groups (t.sub.1 ', t.sub.2 ', t.sub.3 ', etc.) and if the deviation is beyond a permissible range, the level of the braking voltage generated from a motor drive circuit (7) is changed in the subsequent drive period in intermittent recording.

Abstract: When a standby command is issued in a long-period recording (intermittent recording) mode, a control circuit 70 stops the rotation of a rotating drum 60 and a capstan shaft 72 with a magnetic tape 20 being maintained in a loaded state. Then, a back tension arm 310 is moved and rotating torques are applied to a feed reel 11 and a take-up reel 12 in opposite directions, whereby a prescribed back tension is applied to the magnetic tape 20.

Abstract: A process for developing a latent image with a developer is provided which comprises(1) forming a layer of a developer comprising a magnetic toner containing magnetic powder having a BET specific surface area of 2 to 20 m.sup.2 /g on a member for supporting the developer,(2) bringing an electrophotographic photosensitive member holding the latent image into contact with said developer layer, said electrophotographic photosensitive member comprising an organic photoconductive material having a surface hardness more than 10 g,(3) forming a toner image on said electrophotographic photosensitive member,(4) transferring the toner image onto the transfer material, and(5) cleaning the electrophotographic photosensitive member having passed through the transferring step with a cleaning member. Said developer may alternatively comprises magnetic particles containing a binder and magnetic powder having a BET specific surface area of 2 to 20 m.sup.

Abstract: A negative latent image is formed on a photosensitive member comprising an organic photoconductive material. The negative latent image is developed with a positively chargeable developer containing positively chargeable fine silica particles adapted to the organic photosensitive member. The developed image is transferred to a transfer material and the residual toner on the photosensitive member is removed. Thus, copied images without fog can be obtained successively.

Abstract: A developer comprising colored resinous particles and inorganic fine particles having a BET specific surface area of 0.2 to 30 m.sup.2 /g as measured by nitrogen adsorption. The inorganic fine particles have an action of promoting removal of paper powder and other adherents during cleaning of the latent image-bearing member without sticking onto the latent image-bearing member. Accordingly, the developer containing the inorganic fine particles can give good images even after successive copying operation for a long term.

Abstract: A magnetic color toner stable to heat and light which does not fade or discolor for a long period of time is prepared by incorporating .gamma.-Fe.sub.2 O.sub.3 particles as a magnetic component in a toner.

Abstract: A method for applying a toner comprising: forming, in a container containing a toner and magnetic particles for application of the toner, a magnetic brush of the magnetic particles; circulating the magnetic particles in the container; and forming a thin layer of the toner electrically charged on the toner carrying member; wherein the magnetic particles have a particle size distribution of 30 wt. % or more in the range of 150 to 200 mesh and 5 wt. % or less of under 250 mesh, and the weight ratio of the toner to the magnetic particles is from 5:95 to 50:50 in the region where the magnetic brush is formed.

Abstract: A method for applying a toner comprising: forming, in a container containing a toner and magnetic particles for application of the toner, a magnetic brush of the magnetic particles; circulating the magnetic particles in the container; forming a thin layer of the toner electrically charged on the toner carrying member, wherein the magnetic particles have been treated with a substance A having a position opposite to that of the toner in the triboelectric series with the material constituting at least the surface of the toner carrying member as the standard substance and with a substance B having a position between the substance A and the toner in the triboelectric series.

Abstract: A developer contains a silicone oil which has an amine on side chain thereof, a development process comprises arranging a member holding an electrostatic image on the surface and a member for carrying a toner on the surface and a fixing method comprises contacting a toner image on an image-supporting member with a heated roller, said toner image being formed of a toner which contains a silicone oil having an amine on side chain thereof and has an MI of 0.01-10 g/10 min.

Abstract: A developing powder comprises a binder containing 50% by weight or more of a polymer having a gel content of 10% or less and prepared from a vinyl type monomer and a crosslinking agent monomer contained in an amount of 0.01-10% by weight based on the total weight of the monomers, and 0.1-5% by weight of an olefin homopolymer or copolymer having a melt viscosity at 140.degree. C. of 10-10.sup.6 cps.

Abstract: A process for producing a toner includes melt-blending at least a colorant and a polymer and finely pulverizing the resulting blend after cooling, wherein the polymer is a crosslinked resin having a ratio of weight-average molecular weight to number-average molecular weight (Mw/Mn) exceeding 4.0 and a melt index of 0.01-10 g/10 min. at 110.degree. C. under a load of 10 Kg and the polymer is further crosslinked to form gel during the melt-blending. The toner thus obtained exhibits a good fixability without offset phenomenon over a wide temperature range.

Abstract: A magnetic toner comprises magnetic powders having a particle distribution that the particle size of 50% accumulated volume, the particle size of 25% accumulated volume and the particle size of 75% accumulated volume of the magnetic powders are 1.5-4.5.mu., 1.0-4.0.mu. and 2.5-6.0.mu., respectively. This magnetic toner can produce high density and clear images and further, can produce colorful images.

Abstract: A method for developing electric latent images with a triboelectrified toner without use of carrier particles therefor comprises using as a member for imparting triboelectric charges to said toner, a member containing at least on the surface at least one kind selected from poly (phenylene oxide); polycarbonate, styrene type resin, silicone resin, polymer of vinyl ester type monomer, silane compound, and polyethersulfone. Also, an apparatus for developing electric latent images comprises a toner-holding member, a means for supplying a toner to said toner-holding member and a means for moving said toner-holding member and supplying said toner to a portion for development of the electric latent images; in which at least the surface of said toner-holding member contains at least one kind selected from poly (phenylene oxide), polycarbonate, styrene type resin, silicone resin, polymer of vinyl ester type monomer, silane compound, and polyethersulfone.

Abstract: Fixing method, in which developing powder containing therein vinyl type polymers having at least one molecular peak thereof in the molecular weight regions of 10.sup.3 to 8.times.10.sup.4 and 10.sup.5 to 2.times.10.sup.6, respectively, in a chromatogram measured by the gel permeation chromatography (G.P.C.) is fixed by a fuser roller.

Abstract: A developing powder comprises a binder containing 50% by weight or more of a polymer having a gel content of 10% or less and prepared from a vinyl type monomer and a crosslinking agent monomer contained in an amount of 0.01-10% by weight based on the total weight of the monomers, and 0.1-5% by weight of an olefin homopolymer or copolymer having a melt viscosity at 140.degree. C. of 10-10.sup.6 cps.

Abstract: Red to sepia magnetic toners stable to heat and light which do not fade or discolor for a long period of time are prepared by incorporating a partially .alpha.-transformed .gamma.-Fe.sub.2 O.sub.3 as a component in a toner.

Abstract: A developing device in which a one-component magnetic developer is brought into contact with an electrostatic image carrier in a developing station while it is conveyed in a predetermined direction, to thereby develop a desired electrostatic image is provided with developer carrier means carrying the one-component magnetic developer on the peripheral surface thereof and bringing the developer into contact with the electrostatic image carrier, means for moving a magnetic field along the peripheral surface of the developer carrier means to thereby move the one-component magnetic developer in the direction opposite to the direction of movement of the magnetic field, and means for moving the developer carrier means in the direction of movement of the magnetic field.

Abstract: An electrophotographic process comprises the steps of:developing an electric latent image with toner particle, the toner particle comprising 20-70 parts by weight of at least one resin selected from resins of Group A and 80-30 parts by weight of at least resin selected from resins of Group B, transferring the developed toner image to a paper having a smoothness of 5.varies.130 seconds (measured by Bekk method), applying pressure to the transferred toner image to fix the toner image on said paper, and repeating at least said steps, in which said resins of Group A includes a low molecular weight polyethylene, a low molecular weight polypropylene, ethyl ene-ethyl acrylate copolymer, ionomer resin and ethylene-vinyl acetate copolymer, and said resins of Group B includes natural resin modified maleic acid resin, natural resin modified pentaerythritol resin and natural resin modified glycerine resin.

Abstract: A toner for development comprises a crosslinked vinyl polymer having a gel content of 50-99% and a crosslinked vinyl polymer having a gel content of 10-0%.