Abstract: A coating apparatus is disclosed for applying a coating material to the surface of a paper web. The coating apparatus includes a backing roll and an applicator roll which cooperates with the backing roll for defining therebetween a gap for the passage therethrough of the web. The backing roll and applicator roll counter-rotate at given speeds and a nip roll movably cooperates with the backing roll for defining therebetween a nip section. The nip section is disposed downstream relative to the gap such that the web extends progressively through the gap and through the nip section so that the coating material is applied to the surface of the web during passage of the web through the gap and nip section.

Abstract: An improved ductorless liquid distribution system utilizes a plurality of side-by-side mounted radially-compressible roller elements to transfer ink from a reservoir immersed fountain roll in the form of sinusoidal bands onto a longitudinally vibrating distribution roll. The pressure of the roller elements against the fountain and distribution rolls is individually adjustable to control the deformation of the rollers and thus the width of the bands. The distribution roll vibrates an amount equal to the longitudinal spacing between rollers to provide complete inking coverage and the rolls and rollers are relatively dimensioned to obtain the crisscrossing of successive sinusoidal bands and smoothing out thereof by the addition of other vibrating rolls. In a described embodiment for high speed printing presses, the need for a keyed blade and an oscillating ductor is eliminated.

Abstract: The applicator roller (2) can be driven in both directions of rotation. For coating the web of material (3) in the counter-directional mode, a distributor roller (6) is brought up to the applicator roller. In that way it is possible for the film of liquid (1) to be taken from the same reservoir zone (5) as in the co-directional mode of operation. That saves shifting the metering roller (4) which remains at the same position both in the co-directional mode and in the counter-directional mode of operation.

Abstract: An offset lithographic printing machine having a plurality of in-line liquid application stations, at least one of which is an ink image printing station for printing lithographic ink images onto suitable receptive copy sheets, and the final downstream liquid-application station being a coating application station for printing a protective, and/or aesthetic coating over selected portions of, or over the entire ink image-printed surface of the copy sheets.

Abstract: A coater for an offset printing press in which the last printing station, i.e., the blanket cylinder roller with its associated sheet-handling grippers, is converted to coating service, such that a pick-up roller, after an ascending arcuate path not exceeding 80.degree., transfers a liquid coating to an applicator roller rotating in an opposing direction to the blanket cylinder surface which coats the individual imprinted sheets and the liquid coating itself serves as a lubricant permitting said opposing directions of rotation and grippers of said blanket cylinder roller maintain proper handling control of the sheets during the coating thereof. Limiting the arcuate path of 80.degree. obviates reverse flow of the liquid coating on the pick-up roller.

Abstract: Metered application of coating materials, ranging from room temperature to hot melt coatings and adhesives, through the use of fluid-porous roll applicators operating singly or in multiple units for transfer or direct coating, including simultaneous continuous or intermittent patterns and simultaneous different weight pattern coatings or different material coatings.

Abstract: A highly compact machine for applying an attractive protective coating to a paper web that passes through a printing press is located between the last press stand and the dryer of the printing press, and to enable the machine to receive the web, the printing press is provided with an apparatus for directing the web back to the print stands and the machine after the web passes through the dryer. The machine includes upper and lower blanket cylinders, a plate cylinder contacting the lower blanket cylinder, and an oscillating cylinder below the plate cylinder. In addition the coating machine includes a pan containing a coating fluid and a pan roller, the surface of which rotates through the fluid in the pan to lift it out of the pan. A metering roller revolves close to the pan roller to remove excess fluid from the pan roller which thereupon transfers the fluid to a form roller. That form roller runs against the oscillating cylinder and transfers the fluid to the oscillating cylinder.

Abstract: This process is directed to the coloration of envelope and stationery grades of white paper stocks with a water based ink coating. Characteristics of the flexographic process include both press and ink specifications. Critical mechanical or material characteristics are associated with each of the fountain roll, the anilox roll, the plate roll and the impression roll of a flexographic printing system. Used in conjunction with the critical combination of press characteristics is a unique, water-based ink formulation for rapidly coloring an entire web side with a colored ink to simulate the appearance of a colored paper stock.

Abstract: A roll-coating apparatus and method of using it, the apparatus having a pair of narrow rubber tires mounted to be driven by the roll-coater doctor roll, disposed to transfer a narrow band of coating material along the two opposite edge areas of a board which is subsequently coated throughout the full width of the board by the roll-coater main applicator roll.

Abstract: Prior to starting, the size of a clearance, defined on a second end side of a roll when an end of a coating roll is brought into contact with a first end side of a doctor or back-up roll, is measured and stored as data in a memory. After starting, the amounts of movement of both ends of the rolls are controlled in driving of the doctor or back-up roll to be in contact with/separated from the coating roll so that the second end side of the roll is moved by a distance larger by the clearance size than the first end side of the roll on the basis of the clearance size data. Thus, the clearance size is corrected so that the outer peripheral surfaces of the rolls driven to be in contact with/separated from each other are continuously retained parallel in arbitrary moving positions.

Abstract: The end portions of a flexible strip (46,48,50,52) are deflected from the path (54) of an automatic end cementer (10) along which the strip (46,48,50,52) is moved into engagement with cement appliers (62,94) spaced from the path (54). The weight of the unsupported leading end portion (92) causes the end (56) of the strip (46,48) to be deflected downwardly into contact with a cement applier (62) adjustably positioned below the path (54). The trailing end portion (58) is deflected upwardly by changing the direction of the path (54) for the strip (50,52) to lift the trailing end portion (58) from the path (54) into contact with a cement applier (94) adjustably positioned above the path (54).

Abstract: A labeling system where a cylindrical vacuum drum carries plastic labels at spaced intervals on its surface and a solvent applying gravure roll is held at a specific spacing from the drum and labels so that the labels will receive the solvent when they pass the rotating roll. The gap between the drum and the roll must be carefully controlled in order to be assured that the solvent is properly transferred. The gap is controlled by a fine adjustment of the platform on which the roll is mounted relative to the drum by a threaded rod moving a tapered surface of a reciprocable member in contact with a stop block mounted on the platform. The threaded rod threads through a stationary bracket and turns a shaft that threads into the member. The member is prevented from rotation so that rotation of the rod moves the member in one direction while rotation of the shaft moves the member in the opposite direction.

Abstract: An adhesive applicator for a labeling machine. It consists of an adhesive roller, especially one with a resilient surface, of an adhesive-supply mechanism, of an adhesive doctor positioned behind the supply mechanism in relation to the direction that the roller rotates in, and of a label getter with an adhesive-pickup surface that is in particular rigid and that rolls over the surface of the adhesive roller.

Abstract: In a printing machine, a medium applicator disposed downstream of printing units of the machine, in travel direction of a sheet which has been printed, the applicator having three rollers including a first roller for taking up medium from a supply container, a second roller for metering a quantity of the medium to be applied, and a third roller having the same diameter as that of cylinders of the printing units for transferring the medium, includes a rubber lining disposed on the third roller for directly applying the medium onto the printed sheet; the three rollers, during application of the medium, being in constant meshing engagement with a sheet-transferring cylinder; a device for uncoupling the three rollers from the sheet-transferring cylinder, and a separate motor for driving the three rollers when the rollers are uncoupled.

Abstract: A liquid applicator machine of the type operative to apply a liquid such as glue to a moving paper web or the like through a high speed transfer roll which receives a metered film layer of liquid thereon from a pan roller. A static ring is supported in coaxial predetermined spaced relation to each end edge surface of the transfer roll and has an outer annular surface overlapped by the pan roller such that liquid carried upwardly by the end surfaces of the pan roller engages the static ring and is prevented from accumulating at the end edges of the transfer roll and being slung therefrom during high speed rotation of the transfer roll. The invention finds application with full width and segmented transfer rolls to prevent fluid slinging therefrom.

Abstract: A coater includes an impression cylinder and a gravure cylinder rotatably mounted. A first pivot arm unit is pivoted on the impression cylinder shaft and supports a pivot shaft. Depending pivot arms on the shaft support an offset cylinder to one side of the impression cylinder and above the gravure cylinder. Nip adjustment units for the pivot arm unit and the depending pivot arms each include a pre-loaded ball bearing lead screw coupled to a slide housing and a separate power cylinder connected to the pivot unit and pivot arms respectively. The power cylinder unit forces the pivot structure into engagement with the lead screw follower which acts as a stop. A stepping motor rotates the lead screw and accurately positions the stop and thereby the pivot structure as a result of the power cylinder units. The lead screws separately control the nip setting of the off-set cylinder relative to the impression cylinder and the gravure cylinders.

Abstract: Apparatus for production of semiconductor ribbon materials of the type in which molten material is brought into contact with the surface of a rotating cool wheel or drum wherein the cooling surface of the drum is textured to form a plurality of discrete contacting points to enhance growth of large crystal grains.

Abstract: Apparatus for applying a liquid coating to the surface of a sheet workpiece and adapted for operation on-line with the last unit of a lithographic sheet printing press. The apparatus comprises: (1) a textured metering roller in a mount which is linearly movably attached to a support platform fixed adjacent the press unit, and extending between the last press unit and a remote point. The support platform allows movement of the metering roller and the mount between a first position in which the mount is continuously adjustably biased against the last press unit, and a second position, away from the last press unit to allow use of the last press unit as a lithographic press. The platform comprising longitudinal supports arranged generally perpendicular to a vertical plane through the axis of said metering roller, and the metering roller mount is movably supported and guided along the supports.

Abstract: Cold bottles or other containers are transported by a conveyer, and, while being translated, the containers are rotated by a drive belt provided on one side of a line containers. Air is sprayed and coating fluid is applied on other side of the line of containers. Coating fluid is applied onto the containers by fluid application rolls at two levels having axes parallel to the direction of translation of containers. Coating fluid is supplied from spray nozzles to the fluid application rolls through sponge rolls contacting the fluid application rolls.

Abstract: A precision, fully controlled, metering-blade positioning system is achieved by providing dual, precision-constructed, direct, travel-distance measuring means interconnected in a closed loop with dual, blade movement drive motors and an information/movement controller. In the preferred embodiment, the dual, direct, travel-distance measuring means are mounted independently from each other at opposite ends of the blade, thereby assuring that each end of the blade is in the precise, desired position relative to a pre-set reference position. By independently, precisely positioning each of the opposite ends of the metering blade, the user is assured that the metering blade is in the exactly desired position, and in complete, precise parallel alignment along its entire length with a co-operating roller member.

Abstract: Apparatus for continuously brushing and lubricating rolls of rolling mills for rolled flat products without pollution of said products by the lubricant used; it can be used in hot or cold rolling, in particular for Al or alloys thereof.An enclosure of general parallelepipedic shape which is open on one face and whose opposite sides which are adjacent to the opening are delimited by a circular arc, the radius of which is substantially equal to that of the roll, is applied thereto by way of a continuous resilient peripheral seal. The enclosure which contains the rotary brushes is lubricated by oil circulation and is under a slight depression.

Abstract: A liquid coating supply system for a printing press blanket coater is disclosed. The system includes a vessel for holding a supply of the liquid coating material, the holding tray for holding a portion of the liquid coating material for pick up by a feed roller, a first liquid transfer means for transfering the liquid coating material from the supply vessel to the holding tray and a second liquid transfer means for transfering the liquid coating material from the holding tray to the supply vessel. The first liquid transfer means has an adjustable flow valve for regulating the liquid flow from that transfer means, and a supply pump between the supply vessel and the adjustable flow valve for withdrawing the coating material from the supply vessel and for forcing the material through the valve under a pressure which is dependent upon the adjustment of the flow valve.

Abstract: Method and device for impregnating plates (5) with a dispersion (D), whereby the plates (5) are saturated with dispersant (M) in a device (1) and the plates (5) are dried with dry air in a drying system (2) from the surfaces (51) to be impregnated down to a predetermined depth and then the dispersion (D) is introduced with an application device (3) into the dried area and the plates (5) subsequently dried.The application roller (3) is located in a vacuum chamber (7). The plates (5) are conveyed among the various devices (1, 2, 3, 4) with a continuous conveyor (6), a conveyor belt for example.

Abstract: In a printing machine, a medium applicator disposed downstream of printing units of the machine, in travel direction through the machine of a sheet being printed, the medium applicator having an assembly formed of a first roller for taking up medium from a supply container, a second roller for metering a quantity of the medium to be applied, and a third roller for transferring the medium, the third roller having a continuous cylindrical surface with a rubber lining disposed thereon for directly applying the medium onto the sheet, the three rollers being in constant meshing engagement with a sheet-transfer cylinder during application of the medium, the medium applicator further comprising a plate cylinder having a cylindrical surface interrupted by a transverse channel and carrying a flexible relief plate having raised surfaces thereon, and another assembly of rollers for supplying medium from another supply container to the raised surfaces of the flexible relief plate, the plate cylinder being in operative en

Abstract: A paper coloring apparatus particularly for rotation printing presses and, ordinarily for the coloring of white paper to the desired color before the paper web (2) is drawn into the printing press. The paper web (2) passes over several guide rollers (3, 4, 5) plus a displaceable roller (8) which can be displaced towards and away from a coloring roller (10). The coloring roller (10) is supplied with dye from a dye bath (12) via a dye roller (13) which communicates with dye bath (12), and a displaceable intermediate roller (14) which can be displaced towards and away from engagement with the dye roller (13) and coloring roller (10). The displaceable rollers (8, 14) are displaced with the aid of compressed air cylinders (11, 15), and the pressure of the displaceable rollers (8, 14) against the counter-rotating rollers (10, 13) is regulated with the aid of regulation valves in the appropriate compressed air circuits.

Abstract: A spreading head is provided for a wafer sheet coating machine, which comprises a wafer sheet conveyor, which is optionally adapted to be lowered. The spreading head comprises a rotating spreading roller and a sizing device, which cooperates with said spreading roller to control the thickness of a layer of a spreadable composition as it is transferred by said spreading roller. The spreading roller and the sizing device define a lower boundary of a reservoir, which is adapted to hold said spreadable composition and which is laterally defined by platelike elements.

Abstract: An applicator for metering a desired amount of a liquid sizing onto moving glass filaments. In a first embodiment, a foam-covered roller is partially immersed in a reservoir of liquid sizing and is in contact with the smooth surfaced applicator roll. The foam-covered roller is driven in the same direction as the applicator roll and a puddle is formed above the roller/roll nip. The pressure exerted by the foam covered roller on the applicator roll and rate of rotation of the applicator roll determine the size of the puddle, which controls the amount of sizing applied to the glass filaments. A second embodiment employs an elastomeric reservoir which sits generally atop the applicator roll. A plurality of slots in the rotationally downstream side of the reservoir dispense the sizing onto the roll with the pressure between the elements and rate of rotation of the applicator roll, again, determining the application rate. The sizing is pumped through a closed loop to keep its temperature and viscosity more uniform.

Abstract: Disclosed is an overvarnish unit for applying varnish to a web of printed material as a protective overlay. The overvarnish unit includes a varnish fountain for receiving paste varnish, a form roller, and a plurality of rollers intermediate the fountain and form roller. The form roller engages an impression cylinder roller forming part of a printing assembly. The varnish is transferred from the fountain to the form roller by the intermediate rollers which also mill the varnish as it is being transferred to reduce its viscosity. The form roller is driven at a peripheral speed greater than the linear speed of the web over the impression cylinder roller. This form roller overspeed provides a smearing action in applying the varnish to the web rather than a one to one or line by line printing action thus achieving control over the thickness of the applied varnish and the appearance of the final product.

Abstract: An apparatus is provided which applies and cures a coating of viscous ink to a moving strand material. This apparatus includes an ink applicator module which comprises a series of rotatable rollers which receive and apply the ink to the moving strand. This apparatus allows substantial quantities of glass fiber waveguide strand material to thus be coated with a UV curable ink in a relatively short period of time so that they may be color coded to facilitate handling and installation.

Abstract: A roll coating applicator and method for applying a coating fluid to a moving web which includes applying coating fluid through a nozzle to a rotating roll, positioning one or more rolls in coating fluid engaging contact with each other and at least one of which is in coating fluid engaging contact with the first roll, rotating the second roll at a greater rotational speed than the first roll and positioning a portion of a moving web in coating fluid engaging contact with the second or subsequent roll.

Abstract: In a varnish coater, a set of a blanket cylinder and a form roller and a set of a pan roller and a metering roller are driven by different drive sources. One-way clutches are arranged between the blanket cylinder and the form roller and between the form roller and a motor as one of the different drive sources, respectively. The form roller is selectively driven by one of the different drive sources through a corresponding one-way clutch. Alternatively, the form roller is driven by one of the drive sources which has a higher rotational speed.

Abstract: A single facer for manufacturing single-faced corrugated boards comprising a pair of side frames, each side frame having an interior opening which has been formed so that either or both of upper and lower corrugating rolls may be lowered and taken out through it.

Abstract: Device permitting the instantaneous changing of the width of application of glue to a web of paper in the manufacture of corrugated cardboard, the glue being applied to the web with the aid of a gluing cylinder (5) driven rotationally and dipping into a tank of glue over a width adjusted by two barriers which are movable in the tank. It includes a detachable auxiliary doctor device (1) comprising two doctors (2) to be applied momentarily to the two longitudinal ends of the gluing cylinder (5), on the non-immersed top part of the latter, the said doctor device being in addition equipped with a device for adjusting the distance (L3) left free for the passage of the glue between the two doctors.

Abstract: A liquid film as applied to a transfer drum or planar surface by the textural force of a member in a trough which contacts one wall of the trough to prevent entrainment of air into the body by the member, e.g. a roller, while a wiper or the like engages the surface to prevent entrainment of air by the latter into the trough.

Abstract: A device which provides an economical means for coating offset plates on one side with a solvent based coating. An offset plate is advanced along a feed table by a suction belt toward a roller assembly consisting of a fountain roller, a metering roller, a coating roller and an impression roller. The fountain roller transfers liquid from a supply of coating liquid to the metering roller which transfers a predetermined amount of liquid to a moving plate by the coating roller. The impression roller forces the plate into engagement with the coating roller. A photoelectric sensor detects the leading edge of the plate as it moves through the roller assembly and moves the impression roller toward the coating roller to begin the coating application. The sensor detects the trailing edge of the moving plate and retracts the impression roller to stop the coating application. The speed of the feed belt, discharge belt and rollers are synchronized to accurately control the thickness of the coating applied to the plate.

Abstract: A pasting machine having paste applicator roll, a feed roll rotated in a direction opposite to the direction of rotation of the applicator roll and a guide plate surrounding a circumferential region of the applicator roll, said guide plate taking up paste from the feed roll by means of a longitudinal edge facing the periphery of the feed roll and forcing said paste against the said circumferential region so as to uniformly coat the applicator roll with a layer of paste.

Abstract: In a varnish coater for a printed product, a blanket cylinder and a form roller are respectively supported by eccentric bearings to throw on/off the blanket cylinder with respect to the form roller and an impression cylinder and throw on/off the form roller with respect to the blanket cylinder, and rollers provided in the eccentric bearings of the form roller are brought by biasing means into tight contact with the cam surfaces of cams pivoted by pivot means so as to simplify adjustment of a contact pressure of the form roller with respect to the blanket cylinder at the throw-on and -off positions of the blanket cylinder.

Abstract: There is provided a device for removing pinholes produced in printing comprising a levelling roller provided in contact with a form plate and/or a peripheral surface of a blanket cylinder so that an ink film transferred to the plate and/or the peripheral surface of the blanket cylinder may be levelled or smoothed before the ink film contacts a printing object. There is also provided a device for removing pinholes comprising a levelling roller of which peripheral surface is an oil-repellent layer.

Abstract: The invention relates to an apparatus adapted to apply a layer of viscous sticky material, particularly varnish, in the form of a pattern or otherwise, to a substrate. The apparatus comprises an applicator roll 1, and an impression roll 2, between which sheets 3 for printing are fed, by feed means.The means for applying the varnish to the applicator roll consist of a cylindrical screen stencil 8 with an internal squeegee device 9.The applicator roll is also displaceable so that it can be moved away from the impression roll 2 in the absence of a sheet to be printed in the event of a malfunction in the feed means.

Abstract: A method of dispersing a substance in a thin flexible substrate of open-celled foam structure comprising continuously moving a sheet of the substrate, applying the substance to the substrate in a melted condition at an elevated temperature, compressing the substrate, subsequently allowing the substrate to expand to its normal size and thereby draw the melted substance into the open-celled structure to impregnate the substrate and cooling the substrate to solidify the impregnated substance. The method is preferably carried out using apparatus incorporating means for controlling the quantity of substance applied to the substrate by an applicator roller and arranged to permit the substrate to expand while still in contact with the applicator roller.

Abstract: In a three-roller device for uniformly coating a moving web with small quantities of fluid, the middle roller is provided with a contoured or grooved elastic covering, one of the two other rollers with a smooth elastic covering and the third with an incised elastic covering or sheath. Fluid is transferred to the middle roller from the roller which is not in contact with the moving web, the fluid being introduced either via a pool on a trough or via a spraying apparatus.

Abstract: Method and device for the continuous application of a layering mass on boards, whereby a rotating application roller and a rotating smoothing roller located directly behind the application roller in the direction of transport of the boards are used which can be separately driven and adjusted in height, a transport means for the boards is located under the rollers, and a scraper is associated with the smoothing roller. The layering mass is applied to the boards with the application roller and smoothed with the smoothing roller, which rotates counter to the direction of transport of the boards. The layering mass is a mineral fresh mortar which is applied to the boards in the area of the lower gusset between the rollers. The application roller rotates counter to the direction of transport of the boards.

Abstract: A roll-type coater for applying a coating material to a web of paper includes an actuator mechanism for accurately controlling the movement and position of a metering roll with respect to a coating transfer roll, to prevent shock loading of the transfer roll upon closing movement of the metering roll, and to provide for rapid opening of the metering roll when necessary. The mechanism includes a bellcrank and link connected to move the metering roll along guideways, in which the linkage approaches, but does not exceed, an overcenter position just before the metering roll comes into contact with one or more micrometer blocks which space it accurately from the coating roll.

Abstract: A portable coating apparatus is described for use with a paper converting machine such as a corrugated paperboard double-backer. Rotational power to drive gravure, transfer and smoothing rolls is extracted from the converting machine supply web by an S-wrap through the loaded nip between a pair of drive rolls. A low-powered auxiliary drive motor is automatically engaged to keep the gravure and transfer rolls conditioned with coating during brief intervals of web feed cessation. The entire unit is constructed on a space frame that is supported by caster wheels to facilitate movement to and from an appropriate converting machine position which may be between the reeled web supply unwind stand and a web preheating drum station leading into a double-backing machine.

Abstract: Described is a foulard machine with the minimum possible application of liquor. For this purpose, a wiper is held against the circumference of an enlacing roller by means of forces of magnetic repulsion. The wiper has a plurality of recesses or indents next to one another which act to convey the liquor. Any out-of-rounds of the enlacing roller are compensated for by the forces of magnetic repulsion so that the wiper abuts against the circumference of the roller uniformly over its entire length.

Abstract: A method of continuous coating of metallic strip material carried into practice by using a continuous strip coating device wherein the thickness of the coating is decided by a gap between a pickup roll and a thickness control member spaced apart a predetermined distance from the surface of the pickup roll. The method includes the step of (1) setting the pressure of the paint and/or the size of the gap based on the data obtained by preliminary experiments, or (2) directly measuring the gap between the surface of the pickup roll and the thickness control member and feeding back the measurement, to bring the actual size of the gap into agreement with the value set beforehand at all times.

Abstract: An improvement in the type of apparatus for applying adhesive to sheet materials wherein the sheet material is fed between a feed roller and an adhesive coated coating roller, and stripping elements thereafter strip the adhesive coated sheet material from the coating roller. The improvement comprises a main support mounted for rotation about the axis of the cleaning roller, the feed roller and the stripping elements being mounted on the main support for rotation therewith from an operating position to a cleaning position.

Abstract: A changeable liquid reservoir apparatus has a hollow rotating drum, the shaft of which includes an identical coupling on both ends. Both ends of the reservoir include slots which are equidistant from the shaft. Permanently positioned retainer members engage the slots. The shaft of a motor has a coupling which engages the drum coupling. The reservoir, therefore, can be retained in either of two directions and is changeable without the need for tools.

Abstract: Apparatus is provided for making profiled bars for windows, doors and other frames. The profiled bars are profiled metal cores and profiled facings having angled side flanges. The apparatus includes a carrying frame, a conveyor line for handling the profiled metal cores, an adhesive-applying station in the carrying frame, tangentially extending feeders with conveying members for handling profiled facings to be applied to opposite sides of the profiled metal cores, which feeders are provided on the carrying frame behind the station in the direction of travel of the conveyor line and include spreading wedge assemblies for spreading angled side flanges beyond edges of side walls of the profiled metal core.

Abstract: This invention relates to a composition for developing latent electrostatic images by liquid development and a method of transferring the developed image to a carrier sheet over a gap. The gap is formed by dielectric spacing particles disseminated through a dielectric carrier liquid, through which toner particles are also disseminated. The toner particles and the spacing particles bear the same surface charge so as to repel each other while in the developing liquid. Apparatus is provided, for use of the novel developing composition, which includes a metering means adapted to remove excess liquid from the surface of a developed image. In order to induce the spacing particles to migrate toward the photoconductor, the metering means is biased to a potential greater than that of the non-image areas. This enables the spacing particles, which have a higher dielectric constant than the carrier liquid, to migrate toward the photoconductor.