Abstract: In the development of nonuniform latent images on an imaging member, wherein xerographic polar or polarizable toner particles are employed, it is desirable to utilize a development system that will bring the polar or polarizable toner into contact with the latent image without triboelectrically charging the particles and permitting use of nonmagnetic particles when the image is electrostatic and without demagnetizing the latent image when it is magnetic. To achieve this aim, a dielectric brush having convergent electrostatic fields is disclosed and claimed.

Abstract: Liquid ink is held in the openings of a screen which is placed adjacent a grounded conductive surface. Electrical charge is delivered to selected ones of the openings so that the charged ink is drawn to the grounded conductive surface by the attractive forces therebetween. The ink can then be transferred to a record medium in image configuration.

Abstract: An electrostatic imaging system in which a conductive pattern and triboelectric charging are utilized on opposite sides of an electrically insulating member to form a developable electrostatic latent image. Electrostatically charged marking particles are deposited in conformance to the latent image and thereafter transferred to a receiving sheet. Charging, development and transfer are effected without the aid of light or any externally applied voltage.

Abstract: In xerography a positive charge image on the surface of a photoconductor is developed with a blade shaped conductor, and a non-conductive and flexible donor sheet having on one side a negatively charged toner layer. The donor sheet is mounted such that the layer is spaced from but near the surface of the photoconductor, and the conductor is mounted such that its edge slidably abuts the other side of the donor sheet in the region where the sheet is nearest the photoconductor. As a result, the part of the image nearest the edge establishes a non-uniform electrical field between the image and the edge. The non-uniform field is strongest in the region nearest the edge and causes the transfer of toner from the layer to the photoconductor. In one embodiment the donor sheet is in the form of a belt which is driven so that it slides over the edge. The photoconductor is placed on the surface of a rotatable drum and as the drum is rotated the image is developed.

Abstract: A method is provided for transferring a charged particulate image such as a xerographic image across gaps between electrodes where the electrode spacing is much greater than heretofore employed. Thus, envelopes containing bulky objects such as keys, novelties and the like, can be addressed by xerographically forming a particulate image in the conventional manner and transferring it in accordance with the invention. In accordance with the invention, a charged particulate image is deposited on a non-absorbent dielectric transfer sheet and transferred to an absorbent receiver sheet by placing the transfer sheet and receiver sheet between a pair of electrodes having a potential difference sufficient to transfer the charged particulate image, one of the electrodes being a pointed electrode positioned behind the transfer sheet having an emitting angle of between 0.degree. and about 90.degree.

Abstract: Transfer assembly for electrostatic transfer of an electrostatically adherent toner image from a curvilinear surface of an electrostatographic copier. This transfer device comprises, in combination, a web of corona pervious material and a corona discharge electrode. The corona pervious web is preferably in the form of an endless belt and comprises at least 30% voids in order to insure substantially uniform charging of the receiving sheet by applying transfer charges through a corona pervious web holding the sheet against the curvilinear surface by the corona discharge electrode associated with said web.

Abstract: Methods of imaging and printing are provided whereby a transparent self-supporting substrate is coated with a transparent abhesive polymer and an image formed by inking said polymer and simultaneously subjecting said polymer to electromagnetic radiation to reduce the cohesive force of said ink or increase the adhesive force so as to selectively deposit ink in image configuration on said adhesive polymer, and transferring said inked image to a receiver sheet.

Abstract: A charge pattern of a single polarity and having at least three different levels of potential is developed in two colors by utilizing relatively negatively charged toner particles of one color and relatively positively charged toner particles of a second color.

Abstract: A photoconductive member for xerographic applications comprising a mixture of particles of at least two photoconductive pigments capable of generating and injecting holes and electrons dispersed in an insulating binder, capable of transporting holes and electrons in response to imagewise radiation. The photoconductors which are preferred also have a coefficient of absorption between 1/L and 8/L wherein L is the thickness of the photoconductive member in microns. The photoconductive member thus formed is capable of continuous tone reproduction and has improved xerographic characteristics. In a particularly preferred embodiment, one of the photoconductive materials is cadmium sulfoselenide.

Abstract: A portable camera having the photosensitive member including an electrically conductive supportive substrate, a photoconductive layer overlying the substrate, and a leaky dielectric film overlying the free surface of the photoconductive layer. This camera is also provided with an electrically biased pad for contact charging of the photosensitive member and means for development of the photosensitive member within the camera subsequent to latent-image formation. Fixation of the developed image is achieved by overcoating said image with a permanent film or coating.

Abstract: Apparatus for detecting bumps in a web, such as are caused by double threads or knots in a web of fabric, as the web is advanced past the detecting apparatus, comprises a blade, preferably a plurality of partially overlapping blades, arranged across the web and riding on the web. Each blade comprises one element of a switch the other element of which is constituted of a contact member arranged above the blade a distance from the blade greater than the height of the bumps to be detected. The blade is sufficiently light and so mounted that when it is struck by a bump on the web, it bounces out of engagement with the web and contacts the contact member thus closing the switch which is in an electrical circuit. A deactuatable means for moving the web is operatively associated with the switch whereby closing of the switch deactuates said web moving means. A marking means for marking the web when the switch is closed may also be operatively associated with the switch.

Abstract: An apparatus and method for developing a selected image by the electrostatic attraction of development fluid is disclosed. The system utilizes an interposer, adapted to be movably superimposed over a photoreceptor which preferably comprises the outer surface of a rotatable drum. A source of electrostatic charge for applying a first charge of a selected polarity to an area of the photoreceptor, and optical system for subsequently applying a light and shadow representation of the selected image to the area of the photoreceptor are also provided. The system further includes a source of electrostatic charge for applying a second charge, opposite in polarity from the first charge, to a portion of the interposer superimposed over the area of the photoreceptor. The portion of the photoreceptor is adapted to receive a quantity of electrostatic fluid, corresponding to the light and shadow representation applied by the optical system, when moved out of superimposition with the photoreceptor.

Abstract: Disclosed is an improved method for the inking of an inking roller in conventional printing techniques. The method involves applying an ink film to the inking roller which is everywhere thicker than the desired thickness and applying a doctor blade, mounted at a reverse angle, to the ink to split it and apply it to the roller in the desired thickness when relative motion is provided between the roller and the doctor blade.

Abstract: A printing process is provided whereby a resilient image having a relief of from about 4 to 50 microns is formed on the surface of a hard, non-resilient substrate to form a printing member. The printing member is then contacted with a gravure donor member having disposed therein a liquid developer wherein said developer resides within cells from about 4 to 50 microns below the surface of the contact plane at a depth such that the developer contacts the image but not the non-imaged areas of the master so that said contacting selectively transfers said developer to said resilient image but not to the non-imaged areas, and the printing member is then contacted with a receiver sheet to transfer the developed image.

Abstract: In xerography a positive charge image on the surface of a photoconductor is developed with a blade shaped conductor, and a non-conductive and flexible donor sheet having on one side a negatively charged toner layer. The donor sheet is mounted such that the layer is spaced from but near the surface of the photoconductor, and the conductor is mounted such that its edge slidably abuts the other side of the donor sheet in the region where the sheet is nearest the photoconductor. As a result, the part of the image nearest the edge establishes a non-uniform electrical field between the image and the edge. The non-uniform field is strongest in the region nearest the edge and causes the transfer of toner from the layer to the photoconductor. In one embodiment the donor sheet is in the form of a belt which is driven so that it slides over the edge. The photoconductor is placed on the surface of a rotatable drum and as the drum is rotated the image is developed.

Abstract: A migration imaging system having a migration imaging member with a binder layer of softenable material wherein a mixture of electrically photosensitive and inert fusible particles is dispersed and an imaging process wherein the fusible particles are fused thereby fixing the migrated image of the two types of particles. The imaged member is used as a lithographic printing master.

Abstract: An electrostatographic machine is provided with an A.C. corona discharge device having a D.C. bias impressed thereon which is applied to the photoconductive surface prior to the passage thereof through an image transfer zone, the A.C. charge being such as to aid both transfer efficiency and background suppression while the D.C. bias further enhances the efficiency of background removal.

Abstract: A duplicating system for producing collated copy sets from precollated information. The precollated information is stored on a reversibly driven and reversibly developed web member which is driven past a first copy transfer station when moving in a first direction and past a second copy transfer station when driven in a reverse direction. A development station is positioned in the path of the web to develop the precollated information thereon when the web is moving in either direction. Copy sheets are fed by a first transport past the first transfer station to produce copies thereof when the web is moving in a first direction. Copies are fed by a second transport past the second transfer station to produce copies from the developed web member when the web is moved in a reverse direction. The copies are fed to a first copy receiving tray face down when the web is moving in one direction and to a second copy receiving tray face up when the web is moving in a reverse direction.

Abstract: An electrophotographic printing machine and method of use therefor in which a plurality of light images of the same original document are formed. Each of the light images is of a different predetermined magnitude and irradiates a charged photoconductive member to record a plurality of electrostatic latent images thereof. The electrostatic latent images are developed with developer mixes having differing predetermined concentrations of toner particles therein. These developed powder images are transferred, in superimposed registration with one another, onto a common sheet of support material forming a high quality reproduction of the original document.

Abstract: Apparatus for controlling developer efficiency in an electrostatic copying machine. A thin film of semi-insulating material is positioned for advancement through a development zone indicative of the quality of a developer system. Positioned in the path of the film and in the vicinity of the development zone are a plurality of conductive members which are coupled to sources of potential having a difference in voltage of approximately 200 to 600 volts in one embodiment. The difference in potential cause the development along the semi-insulating film material where the electrostatic fields are greatest. The film is then advanced past a detection station which includes an optical sensing device for sensing the transmission of the film and supplying signals indicative of the transmission characteristics to a control circuit which controls the toner dispensing in the developer system.