Abstract: An electric charging member and electric charging apparatus are described, including the surface of the charging member being formed of a resin layer including a nylon copolymer containing at least 15% by weight of nylon 12 or a urethane-modified acrylic resin containing 5-80% by weight of an acrylic resin component.

Abstract: A electrophotographic process for formation of an image is provided, which comprises bringing a metallic charger into contact with the surface of an amorphous silicon photoreceptor, providing a potential difference between the amorphous silicon photoreceptor and the metallic charger to charge the photoreceptor, exposing the photoreceptor to light to form an electrostatic latent image, developing the electrostatic latent image with toner particles to be attached to the surface of the photoreceptor, superimposing a transfer medium on the surface of the photoreceptor, and transferring the toner particles to the transfer medium. The process enables miniaturization of copying machine and energy saving.

Abstract: A method and an apparatus for forming an electrophotographic image based on applying an AC voltage or a voltage obtained by superposing a DC voltage on an AC voltage to an electroconductive base of a sensitive medium having a photoconductive layer formed on the electroconductive base, bringing a grounded electroconductive or semi-electroconductive member into contact with or close to the surface of the sensitive medium to charge this surface to a predetermined polarity, and exposing the surface of the sensitive medium to an image to form an electrostatic image.

Abstract: A contact charging device for charging an outer surface of an electrostatic latent image carrier in contact therewith which has a charging member at least partly in contact with the electrostatic latent image carrier, the portion of the charging member in contact with the electrostatic latent image carrier being formed by a layer containing a copolymer of an olefin-type vinyl monomer and a fluorine-contained monomer, and a power supply for applying a charging voltage to the charging member.

Abstract: A method for measuring an electrostatic potential, in an electrophotographic type image forming apparatus to form an image using a photosensitive drum. An electrostatic potential measuring device is provided opposedly to the surface of the photosensitive drum, and at a position away from a position to which devices such as a charger are opposed, and the photosensitive drum is rotated, immediately after the photosensitive drum stops and the devices such as a charger is turned on for a fixed period of time, and at the same time, the measurement of an electrostatic potential of the surface of the photosensitive drum by the electrostatic potential measuring means is started.

Abstract: A corona generating device of the type in which a control screen adjacent a corona generating electrode regulates the charge flow. The control screen is coated with a substantially continuous layer of boron electroless nickel.

Abstract: Disclosed is a method for patterning a substrate. A laminate of an electrically non-conductive material, an electrically conductive material, and an additional electrically non-conductive material is xerographically processed so as to leave a toner image formed upon the surface of one of the non-conductives. The non-conducive and conductive are successively removed chemically in those areas not coated by the toner, leaving a conductive pattern replica of the original toner image. Subsequent processing yields an exposed conductive pattern overlaying a non-conductive supporting substrate. Xerographic processes includes photocopying and xerographic laser imaging from a low power laser printer. The laminate may be formed in a single step or may be the product of a commercial two layer laminate coated by a standard painting or sealing process.

Abstract: A method of electrophotographically manufacturing a luminescent screen on an interior concave surface of a CRT faceplate panel having a major axis with a first center of curvature and a minor axis with a second center of curvature, the method including the steps of utilizing a charging apparatus for uniformly charging a photoconductive layer disposed on the concave surface of the faceplate panel by providing a corona voltage from a corona generator to at least one corona charger which has an arcuately-shaped charging electrode, the corona charger has a center of curvature substantially concentric with a center of curvature of the concave surface of the panel, a support arm attached to the corona charger is pivotably located at the other center of curvature, the corona charger substantially conforms to, and is spaced from the photoconductive layer on the concave surface, and moving the corona charger across the concave surface.

Abstract: A member for charging comprises a surface layer formed of a N-alkoxymethylated nylon. A contact charging method performs charging of a member to be charged arranged in contact with the member for charging by applying externally a voltage on the member for charging. An electrophotographic device comprises the member for charging and an electrophotographic photosensitive member arranged in contact with the member for charging.

Abstract: There is provided a charging member comprising an electroconductive substrate, and an elastic layer, an electroconductive layer and a resistance layer disposed in this order on the substrate. Such charging member provides good contact with a photosensitive member, to provide good image quality without causing an image defect such as white spot based on charging unevenness. Further, the charging member causes no leak even when the photosensitive member has a pin hole, and reduced the level of noise based on an AC voltage to be applied thereto.

Abstract: An electrophotographic device has an electrophotographic photosensitive member and a blade for charging arranged in contact with the photosensitive member, the photosensitive member being charged by application of a voltage on the blade for charging, wherein the ten point surface average roughness Rz of the photosensitive member is 0.3 .mu.m to 5.0 .mu.m.

Abstract: An electrophotographic printing process is disclosed that comprises the steps of: imagewise exposing a photosensitive means with light of a wavelength at which photochromism occurs, to thereby record the image therein, wherein said photosensitive means has a photosensitive layer formed on a conductive support, said photosensitive layer containing a photochromically sensitive compound that shows photoconductivity when irradiated with light of different wavelengths before and after said photochromism occurs; charging the entire surface of said photosensitive layer; and uniformly exposing said photosensitive means with light of a wavelength at which photochromism does not occur, but at which said photochromically sensitive compound or photoisomeric compound therewith shows photoconductivity, to thereby form the image of a charge pattern on the surface of said photosensitive layer.

Abstract: A control method applicable to an electrophotographic copier for protecting the background of copies against smears due to a residual potential on a photoconductive element. Before a visible pattern is produced, the photoconductive element is charged by a lower potential than a charging potential which is adapted to form a document image and, then, it is discharged. Potential remaining on the photoconductive element which has been discharged is developed to produce the visible pattern, and the density of this pattern is optically detected. Based on the density level of the visible pattern detected, at least one of a developing bias potential, a charging potential and an exposing potential which are to form a document image is corrected. In the event of producing the visible pattern, the potential remaining on the photoconductive element is developed by a developing bias potential which has been corrected on the bias of visible pattern density level detected immediately before.

Abstract: An improved electrostatic image forming apparatus including a controller for controlling the supplied voltage on the grid electrode of the main charger which gives the charges on the photosensitive member. Voltage on the grid electrode is controlled so that the charged potential on the photosensitive member may be held virtually at zero potential after the completion of the image forming operation until the predetermined time.

Abstract: An electrophotosensitive member is uniformly charged and portions to be toned by one type toner are erased. Those portions are filled in with a charge of different potential, for example, a charge of polarity opposite to that of the original charge. The charged member is imagewise exposed and developed with two toners selectively attractive to the different charge potentials. With this method a multicolor image can be formed iwth a single exposure.

Abstract: An improvement in the method and apparatus for producing a multi-color electrophotographic image wherein an electrophotographic medium can be used for multiple charge-expose cycles without the accumulation of trapped charges which can result in an increase in toe voltage. The invention provides for the charging, exposing and toning of the medium to produce a first color visible image. The carrier is then returned to the first position to repeat the foregoing steps to charge, expose and tone to produce a second color visible image. Prior to the second charging step the medium is reverse charged and trapped charges are neutralized to substantially revitalize the medium to a condition closely resemblng its unused condition to substantially eliminate the rise in toe voltage.

Abstract: A method for forming an outline of an image. In this method, at first, an electrostatic latent image bearing member is charged and then irradiated to a positive image to form an electrostatic latent image. Thereafter, the irradiated member is re-charged with a scorotron charger while applying a voltage to a grid, the voltage being lower than the surface potential of the image portion of the latent image, being slightly higher than the background potential of the latent image and being of the same polarity as that of the original charging. By this re-charging, the outline portion of the image is given higher potential than the other portion. Then, the outline portion of the image with higher potential is subjected to a normal development by using a toner charged to a polarity opposite to the polarity of the recharged portions.

Abstract: A subprocess is useful in start-up and shutdown of electrophotographic apparatus of the type designed to tone discharged areas. During the subprocess, a photoconductive member passing through a toning station is subjected to an electrical field tending to inhibit toning even of discharged areas. This permits discharging of the photoconductive member as part of shutdown, start-up or sitting idle. Preferably, the photoconductive member is uniformly discharged directly before the toning station which reduces pickup of developer carrier as well as otherwise benefiting the member.

Abstract: A method of producing an electrostatic charge image comprising the sequential steps of: (1) bringing an electrode into proximity with a photoreceptor, the photoreceptor having a dielectric substrate and a photoconductive film intimately bonded to the substrate, the electrode having means to enable an electric field to be applied across the photoreceptor and being adapted to be brought into proximity with the substrate of the photoreceptor along a length of the electrode and charging the photoreceptor with an electrostatic charge of one polarity and projecting an image of a photograph on the receptor, (2) charging the photoreceptor with an electrostatic charge of opposite polarity, and (3) projecting a photographic image of the subject again on the photoreceptor whereby an electrostatic charge image is formed on the photoconductor surface. The invention also resides in apparatus to carry out the method.

Abstract: An electric photographical copying system which provides a main charger for charging the photo-conductive layer of the recording medium, an optical exposure means for projecting an image of an original onto the photo-conductive layer to make an electrostatic latent image thereon, a developing device for developing the latent image with developer, a transfer device for transferring the image developed onto a copy sheet, a cleaning device for cleaning residual developer on the photo-conductive layer and an erasing device for erasing the surface potential of the photo-conductive layer. The devices are successively activated in an order to use the recording medium repeatedly.

Abstract: Method and apparatus for applying a periodic negative voltage to a coronode for the prevention of a streaming phenomenon in electrographic devices. A negative polarity voltage signal is applied periodically to the bare wire coronode of a positive corona charging device. The negative polarity voltage signal is believed to prevent the formation of streamer sites associated with the pepper tracking copy quality defect. The negative polarity voltage signal is applied to the coronode in a manner having a minimal effect on charging functions.

Abstract: Herein are disclosed polyurethane elastomers comprising a charge-control agent of the formula: ##STR1## The elastomers are useful in making shaped articles.

Abstract: A method of preventing the occurrence of blackened margins on a photosensitive sheet processed in an electrophotographic apparatus. The method comprises the steps of calculating a first sheet transporting length by which the photosensitive sheet is required to be transported until the forward end of an image area of the photosensitive sheet within which an image is allowed to be formed is charged with electricity and a second sheet transporting length by which the sheet is required to be further transported until the rear end of the image area is charged with electricity. A charging device is caused to turn ON when the actually transported length of the photosensitive sheet attains the calculated first sheet transporting length, and then is deactuated to turn OFF when the additionally transported length of the photosensitive sheet attains the calculated second sheet transporting length.

Abstract: An enhanced optically sensitive medium is disclosed which uses an organic charge transfer complex as the switching material. The organic charge transfer complex includes at least one moiety in an oxidized state. An enhancement mechanism is taught which provides a secondary source of neutral molecules of said at least one constituent moiety in the neutral or altered oxidation state. For example, with CuTCNQ used as the switching material, the erasing characteristics can be improved by using a covering dispersion having a matrix polymer interspersed with neutral molecules of TCNQ.degree..

Abstract: A method of producing toner-developed electrostatic images involving the repetitive performance of a copying cycle comprising the steps of corona charging a photoconductive layer at a determined voltage level, information-wise photo-exposing said charged photoconductive layer, developing the exposed photoconductor with charged toner particles to a toner image, transferring the applied toner image to a receptor, and restoring the photoconductive layer to a rest potential for the next cycle; and between successive copying cycles, maintaining said photoconductor in the dark for a randomly varying time period. The number of performed copying cycles in each series is registered by electronic means and an output signal is generated; the period of time between series that the photoconductor is maintained in the dark is measured and a corresponding output signal is generated.

Abstract: Two-color image forming apparatus has a bipolar photosensitive body, a first charging means, a first electrostatic latent image forming means, a first developing means, a second charging means, a second electrostatic latent image forming means, and a second developing means. The second charging means is a corona discharger having a corona ion stream control screen forming by laminating a conductive member with an insulating member and disposed at or near an open portion for radiating a corona ion.

Abstract: An electrostatic printing method is disclosed which improves the print quality by using an infrared or a flash fixing method followed by a charge recovery step whereby the image region potential of the printing master is increased by subjecting the master to one or more charging cycles.

Abstract: An electrophotographic process includes performing removal of electricity or pre-charging by direct current corona discharge and main charging by direct current corona discharge of a polarity reverse to the polarity for removal of electric charge or pre-charging on an organic photoconductive photosensitive layer chargeable at both the positive and negative polarities. Then is performed imagewise exposure, development with a toner and transfer of the toner image. Such operations are repeated to form plural images. Main charging is carried out with an applied current such that the photosensitive layer surface potential is saturated at 500 to 700 volts (absolute value) and removal of electric charge or pre-charging is carried out with at an applied current lower than the saturation injected current value and corresponding to 40 to 90% thereof.

Abstract: An electrophotographic process in which a photoconductive insulating element, comprising a layer of intrinsic hydrogenated amorphous silicon in electrical contact with a layer of doped hydrogenated amorphous silicon, is electrostatically charged to a low level of surface voltage, such as, for example, a level of ten volts, provides an advantageous combination of very high electrophotographic sensitivity with minimal electrical noise.

Abstract: A track recording support for recording devices is suggested with a support (10) made of paper or plastic on which a metallic coating (12) is mounted by means of evaporation and being able to be burned off by means of recording electrodes, in particular an aluminum coating. A lubricant in a finely dispersed form is added to contrast coating (11) for reducing of scratching and grinding traces on the surface of metal coating (12) which reaches metal coating (12) and the freely exposed surface thereof by means of diffusion. Preferably, the lubricant is fed to the contrast substance in a powdery form before the processing of the same. On the one hand, it acts in a physical point of view by a reduction of the slide friction on the surface and, on the other hand, in a chemical point of view in that it substantially prevents the build up of combustion residues from the contrast layer on the recording electrodes.

Abstract: A corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being coated with a substantially continuous thin dehydrated alkaline film of an alkali silicate to neutralize the nitrogen oxide species when generated.

Abstract: A corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being plated with a substantially continuous thin layer of lead to neutralize the nitrogen oxide species when generated.

Abstract: A corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being coated with a substantially continuous thin layer of a paint containing reactive metal particles which will combine with the nitrogen oxide species, the reactive metal being present in the paint in an amount sufficient to neutralize the nitrogen oxide species when generated.

Abstract: The invention relates to a method of forming composite images. After a first electrostatic latent image of positive image is formed on a photosensitive member, a scorotron charger is used to correct the potential of background area to an intermediate potential. Then a second latent image is formed by exposing a negative image to the intermediate potential. This assures production of composite images of high density and good quality free from fog.

Abstract: Apparatus for forming images on a charge-retentive surface including uncharged toner particles which are applied to electrostatic latent images formed on the surface. The latent image is formed on the charge-retentive surface by exposing a charged surface to a light pattern of an image to be reproduced. Prior to image exposure, the charge pattern comprises a periodic line screen pattern which is formed by means of a conductive charging brush having a suitable bias voltage applied thereto at a frequency suitable for forming the line screen pattern. By using such an arrangement charging and screening of the charge-retentive surface occur simultaneously.

Abstract: The printing unit (1) operating with an electrostatic printing aid has an inductor device (7) for transmitting an electrostatic charge to an outer-shell layer (5) of a back-up cylinder (4). The inductor device is provided on one end face (14) of the back-up cylinder and engages over this end face in the manner of a lid. A continuous annular air gap (15) is located between the end face and the inductor device. Inductor electrodes (9) serve for transmitting the electrostatic charge to the outer-shell layer in a contactless manner and are arranged, concealed against outside access, on the inner face of the inductor device and are aligned by means of their electrode tips with an end-face edge (10) of the outer-shell layer (5). So that no impurities can penetrate into the air gap, it is sealed off or constantly scavenged by compressed air.

Abstract: An electrophotographic process employs an electrophotographic photosensitive member of a basic construction in which a photoconductive layer and a transparent insulator layer are sequentially laminated on the surface of a conductive supporter. The process in one preferred embodiment comprises a first step of providing a primary charge uniformly from the surface side of the transparent insulator layer, a second step of performing a secondary corona charging during an imagewise exposure by applying an a.c. voltage in which the firing angle of a negative half wave is controlled in phase to be within a phase angle corresponding to a lower voltage than the firing angle so that the positive discharge period may be longer than the negative one during one period, and a third step of forming an electrostatic latent image on the transparent insulator layer by applying a uniform exposure.

Abstract: In practicing multi-step reproduction of color image by electrophotography using an electrophotographic photosensitive material prepared by overlaying a photosensitive layer composed mainly of titanium dioxide and a binder on an electroconductive substrate, exposure to an optical image is first carried out, then positive corona charging is carried out to form a positive electrostatic latent image and subsequently developing is carried out. Further, prior to the exposure to an optical image, negative corona charging and/or AC corona charging are additionally carried out. By this electrophotographic process effectively utilizing the photomemory effect of titanium dioxide, multi-color images can be produced, and an image having good contrast can be reproduced easily and stably.

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: An electrophotographic printing machine in which a controller regulates charging of a photoconductive member in accordance with information stored therein. The controller determines the charging current as a function of the rest time between successive copying cycles.

Abstract: In an electrophotographic reproduction apparatus and method, a moving photoconductor is charged by a primary corona charger that includes a corona wire. Nonuniformities in the charge pattern produced on the photoconductor by this primary line charger are reduced by subjecting the photoconductor to a second corona charger having point charging electrodes.

Abstract: An electrophotographic imaging method comprises a first process for charging an electrically insulating layer formed on the surface of a photosensitive drum, and a second process for image-exposing the charged insulating layer to form an electrostatic latent image thereon. The first process includes a first step for bringing a pliable contactor having a specific electric resistance of 10.sup.8 .OMEGA..multidot.cm in contact with the insulating layer, and a second step for impressing a voltage on the contactor in contact with the insulating layer by means of an electrode having a specific resistance lower 10.sup.5 to 10.sup.7 .OMEGA..multidot.cm. Thus the insulating layer is charged.

Abstract: Disclosed herein is an electrophotography process for controlling the potential on a movable photosensitive member having a photoconductive layer to form a latent image on the photosensitive member. The moving speed of the photosensitive member is changed by setting a magnification changing mode, and, when the latent image is formed on the photosensitive member moving at the changed speed, a quantity of a first corona discharge applied to the photosensitive member is changed at a time prior to the latent image formation.

Abstract: Apparatus for making an electret tape having an electrically conductive strip with a dielectric layer on one side thereof comprises tape supply and take-up reels arranged to move the tape from the former to the latter in an upwardly inclined plane and an electrostatic charging assembly between the reels having a dielectric fluid applicator for applying the fluid directly to the dielectric layer, a sponge-like electrode connected to a high dc voltage source, and an air blower for drying the fluid on the tape. The electrode is longitudinally spaced from the fluid application point in the direction of tape movement, engages the dielectric layer across its full width, and is wetted on the tape input side by the fluid on the layer. The blower is on the tape output side of the electrode with a baffle spaced closely to the dielectric layer between the blower and the electrode.

Abstract: An electrophotographic copying method suitable for a toner image transfer type copying apparatus is disclosed. Using a photosensitive member which comprises at least a photoconductive layer formed over a conductive base which is prepared from a dispersion of a photoconductive material including at least cadmium sulfide in a binder resin and in which a portion of photosensitive member is used repeatedly for forming an image of original to be copied, the method is characterized by performing a first step of charging said photosensitive member to high potential and to the same polarity as applied thereto for the formation of electrostatic latent images and subsequently exposing to light to sensitize said photosensitive member, said high potential being high enough to saturate the degree of sensitization; and a second step of charging the photosensitive member after the first step, and subsequently exposing the photosensitive member to an optical image to form an electrostatic latent image thereon.

Abstract: A method for improving the sensitometric response of a persistently conductive photoreceptor is disclosed. This method involves charging and exposing the photoreceptor to form a latent electrostatic image and thereafter, within the period of persistence, recharging the photoreceptor to the same polarity and developing the latent electrostatic image.

Abstract: A charging method of an electrostatic image developer which makes it possible to electrically charge an insulating one-component developer or a two-component developer consisting of a toner and a carrier to a desired charged state and which comprises introducing the developer into a charging space between a pair of sheet-like charging members opposing each other in which space an alternating field is formed, and oscillating the developer by means of the alternating field for charging it. A developing method of a non-contact or contact system which develops the electrostatic image by use of the developer charged electrically by the above-mentioned charging method.

Abstract: In an electrostatic printing method of the type wherein a toner image is fixed on a printing master, the master is repeatedly run through a charging operation with a discharging lamp or the like maintained off, until the potential thereof reaches a value approximating a practical printing value. The lamp is then turned on and the master again repeatedly charged until the practical value is reached, prior to using the master for printing.

Abstract: An electrophotographic copying process utilizes a photosensitive member for electrophotography which comprises a first and a second photoconductive layer which are sensitive to radiation of a first and a second wavelength region, respectively.

Abstract: This invention is directed to an improved ambipolar photoresponsive device useful in imaging systems for the production of positive images, from either positive or negative originals, which device is comprised of:(a) supporting substrate,(b) a first photogenerating layer,(c) a charge transport layer, and(d) a second photogenerating layer,wherein the charge transport layer is comprised of a highly insulating organic resin having dissolved therein small molecules of an electrically active material of the formula: ##STR1## wherein X is selected from the group consisting of alkyl and hal