摘要:
A direct electrostatic printing device includes a printhead structure with apertures and control electrodes associated with the apertures for delivering toner from a toner source to a substrate in accordance with image data. A first voltage source is provided to establish a flow of toner particles from the toner source to the substrate. A second voltage source is provided to establish a control voltage between the toner source and the control electrodes to control toner flow in accordance with the image data. The second voltage source provides a first AC field between a toner source and the control electrodes to permit toner flow and a second, diminished, AC field between the toner source and the control electrodes in order to stop the toner flow.
摘要:
A printer, with printing width (PW), is provided, for printing toner image on a substrate, having a width (WS) and a length (LS), comprising a DEP printing engine, havinga toner delivery means, having a surface whereon charged toner particles are present for providing a flow of the toner particles from that surface to the substrate,a printhead structure with printing apertures and control electrodes, interposed in the flow of toner particles for image-wise controlling that flow, wherein:the toner delivery means comprises a number, n equal to or larger than 2, of toner applicator modules, each having a width, WTD, smaller than the printing width PW, and at least two of the number, n of toner applicator modules are positioned in a staggered configuration with respect to the substrate.Preferably the printing width of the printer is at least 40 cm.
摘要:
A printer, with printing width (PW) of at least 30 cm printing a toner image on a large substrate, having a width (WS) and a length (LS), including a latent image bearing member having a width (WLI) equal to or larger than the printing width and at least two means for delivering toner are arranged in a staggered configuration around the latent image bearing member and each having a width (WTD) smaller than the width (WLI) of the latent image bearing member.Preferably the latent image bearing member is a photoconductive member.A printer with a shuttle having a swath width of at least 30 cm is also disclosed.
摘要:
A single pass printer, having a printing width (PW) is provided or printing a toner image on a substrate, the substrate having a width (WS) and a length (LS), wherein, i) a number n, equal to or larger than 2, of printing engines, each containing a toner transferring element with a longitudinal axis (width (WPE)) smaller than the printing width (PW) are present, and at least two of the n printing engines, each containing a toner transferring element with a longitudinal axis in the direction of width (WPE), are located so that the longitudinal axis do not coincide. Preferably the printing engines are electro(stato)graphic engines, especially Direct Electrostatic Printing (DEP) engines or electrophotographic engines.
摘要:
A single pass printer, having a printing width (PW) is provided for printing a toner image on a substrate, the substrate having a width (WS) and a length (LS), wherein, i) a number n, equal to or larger than 2, of printing engines, each containing a toner transferring element with a longitudinal axis (width (WPE)) smaller than the printing width (PW) are present, and at least two of the n printing engines, each containing a toner transferring element with a longitudinal axis in the direction of width (WPE), are located so that the longitudinal axis do not coincide. Preferably the printing engines are electro(stato)graphic engines, especially Direct Electrostatic Printing (DEP) engines or electrophotographic engines.
摘要:
An apparatus for direct electrostatic printing includes a back electrode and a printhead structure having a plastic insulating layer and printing apertures arranged therein. Individual control electrodes are combined with the printing apertures on a first side of the insulating layer, and a shield electrode is combined with the printing apertures on a second side of the insulating layer. A toner delivery apparatus is also included for delivering a cloud of dry toner particles in the vicinity of the printing apertures. The printing apertures are constructed and arranged such that, when applying a potential difference of 200V between the shield electrode and each individual control electrode, a current of no more that 50 .mu.A flows from each individual control electrode to the corresponding shield electrode through the corresponding printing aperture. Methods for forming the printing apertures in such a printhead are also disclosed.
摘要:
A printhead structure is provided comprising individual control electrodes (106a) in combination with printing apertures (107) and a shield electrode (106b), both electrodes separated by an insulating material wherein both the shield electrode and the control electrodes have openings and either the shield electrode or each of the control electrodes does not reach as far as the edges of the printing apertures. The linear dimension of the openings in the shield electrode or in each of the control electrodes is at least 1.1 times larger than the longest linear dimension of each of the printing apertures present in the openings. A DEP device using such a printhead structure is also disclosed.
摘要:
A device for direct electrostatic printing (DEP) including a back electrode, a printhead structure made from an insulating material and having a control electrode in combination with printing apertures, and a toner delivery apparatus that presents a cloud of toner particles in the vicinity of the printing apertures, in which the printhead structure is tightly stretched over a frame by means of lateral forces and the printhead structure has an overall flatness equal to or better than 50 .mu.m.
摘要:
A device for use in the technique of direct electrostatic printing (DEP) on an intermediate or final substrate is described, comprising a receiving member support 5 having control back electrodes 5b and a common shield back electrode 5a; a printhead structure 6 having control print electrodes 6a in combination with apertures 7 and a common shield print electrode 6b; a toner delivery means 1 presenting a cloud 4 of toner particles in the vicinity of said apertures 7. The control print electrodes 6a in the printhead structure 6 and the control back electrodes 5b in the receiving member support 5 are positioned in a 1 to 1 relationship, and the control electrodes of both the printhead structure 6 and the receiving member support 5 are driven in an imagewise manner by a variable voltage source, in order to get a specific toner density on the receiving member substrate 9.
摘要:
A DEP device is provided that comprises a back electrode (105), a printhead structure (106), an array of printing apertures (107) in the printhead structure (106) through which a particle flow can be electrically modulated by a control electrode (106a), a toner delivery means (101), presenting a cloud (100) of dry toner particles in the vicinity of the apertures (107), characterized in that the toner cloud (100) is formed in the vicinity of the apertures (107) by means of a gas stream. The toner cloud is formed by detaching toner particles from a charged toner conveyer by the gas stream, or by forming a fluidized bed of toner particles.