Abstract: A web material is disclosed comprising a substrate in web form and multiple microwells, arranged on said substrate in a predetermined pattern and separated from each other by separating zones, each microwell comprising a bottom and an upstanding surface formed by the adjacent separating zones, wherein the composition of said bottoms on the one hand and the composition of said separating zones and upstanding surfaces on the other hand show a different hydrophilicity.

Abstract: Methods and apparatus for rapid screening of layered materials, for a useful property. In the method at least two layered materials are applied on one single substrate. Preferably the materials are applied by coating from a coating composition and are multi-layered materials having at least two distinct layers.

Abstract: A device for direct electrostatic printing (DEP) is provided comprising a device having an external surface carrying toner particles for generating a flow of toner particles to an image receiving member and a printhead structure, having two major faces, interposed in the flow of toner particles for image-wise modulating this flow, wherein the external surface moves in a direction A and the printhead structure is kept at a constant distance, D, from that external surface by spacing elements forming an angle between 45° and 0° with direction A and being located at a distance d from each other such that 1 cm≦d≦50 cm. In a preferred embodiment the spacing elements are located at a distance d such that 5 cm≦d≦35 cm and the constant distance D is kept between 25 and 500 &mgr;m.

Abstract: 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.

Abstract: A method for printing an image on a substrate by image-wise depositing, toner particles on the substrate, is disclosed, comprising: image-wise depositing dry toner particles on the substrate forming a first band-like portion of the image, conditioning the first band-like portion while keeping the substrate at a temperature equal to or lower than 100° C. and further image-wise depositing toner particles on the substrate so as to form at least one other band-like portion of such image, the at least one other band-like portion of the image being adjacent to the first band-like portion. Preferably the method is used for printing substrates with an area equal to or larger than 0.25 m2.

Abstract: A DEP device is provided that comprises a printhead structure with control electrodes in combination with printing apertures and a magnetic brush assembly delivering a cloud of toner particles in the vicinity of the printing apertures, wherein the toner particles are, together with magnetically attractable carrier particles part of a multi-component developer further and the magnetic brush comprises a magnetic core rotating at a speed equal to or higher than 500 rpm (rotations per minute) and a sleeve rotating at a speed equal to or lower than 10 rpm (rotations per minute).

Abstract: 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.

Abstract: A Direct Electrostatic Printing (DEP) device is provided that includes a back electrode (105), a printhead structure having an insulating substrate (102), a control electrode (102a) and a slit aperture (103) through which a particle flow can be electrically modulated by the control electrode (102a), and a toner delivery means (101), in which control electrodes (102a) are present only on one side of the slit aperture. In a preferred embodiment the printhead structure is realized by a slit having two sides, side A (SA) and side B (SB), defined by two edges (A and B), which are formed by at least one sheet of insulating material. The insulating material has an elasticity modulus (Young's Modulus, YM) fulfilling the equation 0.1 GPa.ltoreq.YM.ltoreq.10 GPa and the edges A and B are placed with respect to each other at an angle .alpha. fulfilling the equation 0.degree..ltoreq..alpha.<45.degree..

Abstract: 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.

Abstract: 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.

Abstract: A method for direct electrostatic printing includes the steps of providing a magnetic brush carrying carrier particles and toner particles, the carrier particles having a specific volume resistivity of between 10.sup.1 .OMEGA..multidot.cm and 10.sup.9 .OMEGA..multidot.cm and a specific density lower than 5 g/cm.sup.3, creating in an electrical field a flow of charged toner particles directly from the magnetic brush to a substrate, image wise modulating the flow of charged toner particles by a printhead structure having printing apertures and control electrodes, image wise depositing toner particles from the image wise modulated flow of charged toner particles on the substrate, and fixing the toner particles to the substrate.

Abstract: 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.

Abstract: A method and apparatus is provided for a direct electrostatic printing on a substrate irrespective of the surface topology and conductivity of the substrate. A conductive layer is applied to a surface of the substrate to be printed. A voltage source is connected to establish a DC electric field between the conductive layer and a source of toner particles to create a flow of toner particles from the source to the surface of the substrate. A printhead structure is provided between the source and the substrate to image-wise modulate the flow of toner particles, and the toner particles are fixed on the substrate.

Abstract: A device for use in the technique of direct electrostatic printing (DEP) images onto an intermediate or final substrate. The direct electrostatic printing device includes a receiving member support and a printhead structure which has shield electrodes on a first side and control electrodes on a second side, and which also has apertures therethrough. There is one shield electrode and one control electrode for each aperture. The direct electrostatic printing device also includes a toner delivery mechanism which provides a cloud of toner particles in the vicinity of the apertures. The printhead structure is made of a plastic isolating substrate. The voltage applied to the individual control electrodes is varied according to the contents of the image being printed. A correction voltage is applied to each individual shield electrode and is tuned according to the characteristics of the particular aperture which corresponds to that shield electrode.

Abstract: 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.

Abstract: A printhead structure (106) for use in a DEP (Direct Electrostatic Printing) is provided, made from an insulating material comprising a control electrode in combination with printing apertures (107) and being installed between a toner delivery means (101) and a image receiving substrate (109), characterised in that the printhead structure comprises:(i) one individual control electrode (106a) around each aperture (107) on one side of the insulating material (106d) of the printhead structure,(ii) one individual shield electrode (106b) around each aperture (107) on the other side of the insulating material (106d) of the printhead structure, wherein each single electrode of the individual control electrodes (106a) and each single electrode of the individual shield electrodes (106b) arranged around each aperture (107) are connected to each other via metallisation (106c) through the single aperture (107), forming a single printing electrode around each aperture (107).

Abstract: 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.

Abstract: 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.

Abstract: There is provided a device for direct electrostatic printing comprising a back electrode (105), a printhead structure (106), an array of printing apertures (107) in said printhead structure (106) through which a particle flow can be electrically modulated by a control electrode (106a), an image receiving substrate (109) travelling between said back electrode (105) and said printhead structure (106) in the direction of arrow A and toner delivery means (101), comprising a charged toner conveyer (103), the reference surface of said charged toner conveyer being placed at a distance B (in mm) from the front of said printhead structure (106), and a magnetic brush to provide charged toner on to the CTC, wherein the linear surface speed of the magnetic brush LSM has a specified minimal ratio versus the travelling speed LSS of the image receiving substrate, such that LSM/LSS.gtoreq.0.5.

Abstract: 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.