Abstract: A process of forming on a copying material from an original having respective minimum and maximum density values D.sub.min and D.sub.max a copy having respective minimum and maximum density values P and Q, different from D.sub.min and D.sub.max, comprising the steps of: forming first and second non-superimposed test wedge images by exposing first and second specimens of the copying material to light of respective first and second colors, the exposure of the first and second specimens being such that the respective average exposure times are T.sub.B and T.sub.G, with the exposure to light varying across each specimen according to a preselected relationship, determining from the first test wedge image the density values D.sub.1 and D.sub.3 which an original must have to produce upon the copying material the respective density values P and Q if the copying of such original onto the copying material is performed with light of the first color for an exposure time T.sub.

Abstract: A web with overlays for use in the document presentation device of a photographic copying machine has several sheet-like sections with overlapping portions which are separably coupled to each other by snap fasteners and carry overlays which are welded thereto by the application of heat and pressure. The overlays are applied to those sides of the sections which are coated with layers of photographic emulsion.

Abstract: An image consisting of a multitude of image points is formed by effecting relative transport between a plurality of light-emitting diodes and a recording medium. The diodes are arranged in rows. The rows are arranged successively in the transport direction. The rows extend at an angle relative to the transport direction. The diodes of each single row are offset relative to those of the other row, in direction transverse to the transport direction, by an amount equal to the distance between adjoining diodes in a single row divided by the number of rows, and/or multiples of that amount. Each diode is provided with an optical unit which projects onto the recording medium a reduced image of the light emitted by the diode.

Abstract: Relative movement is effected between a recording medium and a row of light-emitting diodes (LED's). The row of LED's extends parallel to the direction in which the line of image points to be formed extends, and transverse to the direction of relative movement. Reduced-scale images of the LED's are projected onto the line on the recording medium on which the line of image points is to be formed. The LED's and/or the optical units forming the reduced-scale images are oscillated in a direction parallel to the direction in which the line of image points to be formed extends. Each image of an LED sweeps a straight linear region on the recording-medium line at least equal in length to the distance between adjoining LED's of the LED-row. During each n.sup.th half-period of oscillation, a succession of control signals is applied to each LED, determining a succession of adjoining image points which the respective LED forms upon the recording-medium line in question; n is an integer.

Abstract: A sheet-holding cassette for a copying machine is formed as a box containing a stack of copy sheets. This box is adapted to be held in the machine with the uppermost sheet of the stack engageable with the paper-advance roller of the machine. A slot is provided in the upper wall of this cassette as well as a guide next to this slot and a deflector in back of this slot so that an extra sheet can be slid along the upper wall of the machine and into the cassette to lie at least at its front edge on top of the stack of sheets in the cassette. Thus as the paper-advance roller is reciprocated down onto the stack it will pick up this extra sheet rather than the top sheet of the stack, allowing a copy to be made on a single extra copy sheet without having to reload the machine.

Abstract: A cartridge is disclosed in which a hub is rotatable in a housing and has its periphery partly embraced by an endless band that is mounted for travel in the housing. The band is trained about a plurality of guide rollers at least one of which is located outwardly adjacent the hub and is mounted so that it can move towards and away from the hub. Movement away from the hub is opposed by a permanently acting biasing force.

Abstract: Sheet-like dielectric receptors which are to be exposed to object-modulated X-rays in the interelectrode gap of an ionography imaging chamber are attached to sheet-like carriers so that the carriers extend laterally beyond the reactors. The carriers are thereupon transported through the interelectrode gap and through successive stations of a xerographic printer which renders the latent imges of objects visible and subjects the receptors to other treatment. The carriers can be attached to receptors by resorting to an adhesive, by the application of electrostatic charges and/or by causing the marginal portions of the carriers to engage the receptors by suction.

Abstract: An electro-photographic copier has a strip-shaped latent-image carrier which is payed out from a supply and taken up by a take-up. An image-forming station is provided at which an image of an original to be copied is formed on the image carrier, and a guide arrangement guides the image carrier on its way from the pay-out to the take-up in a path including at least adjacent the image-forming station a planar portion in which successive image-receiving increments of the image carrier travel past the station in substantially planar condition.

Abstract: An ionography imaging chamber for use in the cassette of an X-ray apparatus has a flat prismatic pressure vessel defining an interelectrode gap for compressed high Z gas and a dielectric charge-receiving sheet which is to be exposed to a pattern of X-rays. The pressure vessel fits into the compartment of a strongly deformation-resistant jacket having a centrally located sleeve consisting primarily of polyurethane foam, a thin tubular inner envelope which consists at least in part of convoluted fibrous material, and a thin tubular outer envelope which also consists at least in part of convoluted fibrous material. That envelope which takes up compressive stresses has a layer of carbon epoxy fibers. The other envelope takes up tensional stresses and contains Kevlar fibers. The pressure vessel has two flat tray-shaped main portions which consist of polyurethane foam.

Abstract: Apparatus for wet treatment of webs of photographic material has a series of chambers each of which defines an upper and a lower horizontal path for the transport of webs therethrough and a discrete liquid collecting tank below each chamber. Each chamber has an upper section above the upper path, a median section between the two paths and a lower section below the lower path, and each section has an inlet which receives liquid from the tank through the medium of a pump and an upright pipe which latter can constitute a support for the respective chamber. The liquid which issues from the inlet of the median section of a chamber is divided into two streams which respectively contact the undersides and upper sides of webs in the upper and lower paths. The upper sides of webs in the upper path are contacted by liquid issuing from the inlet of the upper section, and the undersides of webs in the lower path are contacted by liquid issuing from the inlet of the lower section.

Abstract: An electrostatic copying machine wherein a carriage is reciprocable between a horizontal copyboard for originals and the flat upper reach of an endless backing belt the outer side of which has a photosensitive surface. The carriage supports at least one exposing device which exposes line images of the original onto the upper side of the upper reach of the belt while the carriage moves from a starting position and the belt is at a standstill. The carriage further supports a corotron which is mounted ahead of the exposing device and charges successive increments of the upper reach, and a developing device which applies toner particles to the electrostatic image on the upper reach. The belt is thereupon moved to transfer the thus obtained powder image onto a paper sheet. The exposing device has several strip-shaped optical imaging components, and the developing device employs a rotary magnetic drum or a set of magnets which are fixedly mounted on the carriage.

Abstract: An electrostatic copying machine wherein the copying drum and the cleaning unit for the photosensitive layer of the drum are mounted in the plastic casing of a module which can be inserted into the stationary main portion of the housing upon pivoting of a cover to open position. The main housing portion and the cover carry rollers which automatically center the copying drum of a properly inserted module when the cover is moved back to closed position. The casing of the module has a vessel for a supply of developing or fixing liquid and means for automatically feeding liquid to a tank in the main portion of the housing when the supply of liquid in the tank descends below a predetermined level. One of the rollers can be driven by the motor of the copying machine to rotate the drum when the latter is properly centered in the housing.

Abstract: A copying machine wherein successive finished sheets issue from an opening in the front wall of the housing in such positions that the printed matter is observable from above. Successive sheets pass below an observation window which is adjacent to the opening so that the quality of printed matter can be observed from above. The sheets are thereupon inverted so that the printed matter faces downwardly, and are stacked on top of each other in a tray having a bottom panel the inner end portion of which constitutes the observation window. The sheets are inverted in a channel having an inlet below the observation window and an outlet above the end of the tray which is remote from the opening.

Abstract: In an electrostatic copier using a particulate developer mix the invention provides a source of the mix, a supply ramp having an inlet end located higher than the source, and a conveyor for conveying the developer mix from the source to the inlet end of the supply ramp. The conveyor is composed of an endless flexible belt trained about at least one driven roller and having one end portion which extends into the source and another end portion which discharges onto the inlet end of the ramp. A plurality of pins is anchored in the belt and projects from a conveying surface thereof so as to entrain the developer mix from the source.

Abstract: Alkali or alkaline earth metal salts of the reaction product of certain polyalkylene glycols of the formula ##EQU1## wherein N = 0 TO 100(m+p) = 10 to 500 ##EQU2## WITH A SULTONE. These products are superior and long lasting antistatic agents for use in connection with polyamide synthetic fibers.Polyamides compositions having antistatic properties as well as methods for manufacture of such compositions are also disclosed.