Abstract: The invention is an electrostatographic printer and a method of printing with such a printer. The printer includes a transfer member that is driven along a continuous path, and a toner image depositor that deposits a toner image in powder form on the transfer member. A substrate is fed into contact with the transfer member, and the toner image on the transfer member is heated in advance of the transfer; the transfer member is cooled following the image transfer to a temperature below the glass transition temperature T.sub.g of the toner; then further toner images may be deposited on the transfer member. A controlling pressure roller is positioned in opposition to the transfer member to form a transfer nip, through which the substrate passes, the substrate wrapping partially around the pressure roller both in advance of and following the transfer nip.

Abstract: A single-pass, multi-color electrostatographic duplex printer has a transfer member which is driven along a continuous path. Toner images of different colors are simultaneously electrostatically deposited in powder form in register with each other on the transfer member to form a multiple toner image. The substrate is fed into contact with the transfer member for transfer of the multiple toner image to at least one face of the substrate. The printer includes a heater for heating the multiple toner image on the transfer member in advance of the transfer of the image to the substrate.

Abstract: A substrate carrying an unfixed toner image is fed through a contact zone which extends continuously from an entrance to an exit (18; 78). The zone is defined by an endless surface such as a first belt and a reaction surface such as a second belt in face-to-face pressure contact therewith. The first belt adjacent the entrance is heated to a temperature sufficient to reduce the viscosity of the toner to less than 50 Pa s. The first belt is forcibly cooled intermediate the entrance and the exit to a temperature below the glass transition point T.sub.g of the toner. Thereby un-fixed toner images can be fixed to the substrate and provided with a desirable level of gloss in one single device, while widening the range of operating conditions without risk of offset occurring.

Abstract: A single pass, multi-color electrostatographic printer includes a transfer member which is driven along a continuous path. Several toner images of different colors are electrostatically deposited in powder form in registration with each other on the transfer member to form a multiple toner image thereon. A substrate is fed into contact with the transfer member. The multiple toner image is thereby transferred to at least one face of the substrate. The printer includes heaters for heating the multiple toner image on the transfer member in advance of the transfer of the image to the substrate and cooling devices for cooling the transfer member following the transfer of the multiple toner image therefrom to the substrate to a temperature below the glass transition temperature T.sub.g of the toner, prior to the deposition of further toner images on the transfer member.

Abstract: An electrostatographic single-pass multiple station multi-colour printer for forming an image onto a web. The printer has a plurality of toner image-printing electrostatographic stations. Each station has a drum onto the surface of which a toner image can be formed. An exposure station forms an electrostatic toner image line-wise on each drum surface. A corona device transfers the toner image onto the web, which is conveyed in succession past the stations in synchronism with the rotation of the drum surface. A register control device is provided for controlling the operation of each of the stations in timed relationship thereby to obtain correct registering of the distinct toner images on the web. The register control device includes an encoder driven by the displacement of the web to produce pulses indicative of web displacement, and delay system arranged to initiate the operation of subsequent stations after a predetermined web displacement, as measured by the encoder, has occurred.

Abstract: A single-pass, multi-color electrostatographic printer has a transfer member which is driven along a continuous path. Toner images of different colors are simultaneously electrostatically deposited in powder form in register with each other on the transfer member to form a multiple toner image. The substrate is fed into contact with the transfer member for transfer of the multiple toner image to at least one face of the substrate. The printer includes a heater for the multiple toner image on the transfer member in advance of the transfer of the image to the substrate, and cooling capability for the transfer member following the transfer of the multiple toner image to the substrate, to a temperature below the glass transition temperature T.sub.g of the toner, prior to deposition of further toner images on the transfer member.

Abstract: An electrophotographic printer includes a plurality of recording heads connected in series in a closed cooling circuit. Each of the recording heads includes a linear array of light-emitting diodes (LEDs) on a common thermally conductive LED carrier bar. The carrier bar carries a series of modules, each module containing N LEDs with their associated drivers. The carrier bar is provided with a U-shaped duct inside a thermally conductive body which is in thermally conductive contact with the carrier bar. The duct extends between a fluid inlet and a fluid outlet and has a cooling fluid such as water flowing therethrough.

Abstract: An electrostatographic printer for forming an image onto a web comprises at least one toner image-producing electrostatographic station having a drum onto which a toner image can be formed, a transport for conveying a web past the image-producing station, apparatus for controlling the speed and tension of the web while it is running past the image-producing station, and transfer apparatus for transferring the toner image on the drum onto the web. The printer is characterized by a control arrangement for switching between a printing mode wherein a printing web moves in synchronism with the peripheral speed of the drum and a refurbishment mode wherein a refurbishment web moves at a faster speed relative to the peripheral speed of the drum and in contact therewith, to cause refurbishment of the drum surface.

Abstract: A method of forming a drum assembly for use as a rotatable endless surface onto which a toner image is formed. The drum assembly has a hollow drum with an opening at each end and a surface onto which the image is formed. A support flange, having an aperture in the center thereof, is cooled before being inserted into each end opening. The drum assembly also includes a shaft having a collar fixed in the vicinity of each end. After the shaft is positioned inside the drum, the collars are positioned to coincide with the flange apertures. Screws secure each collar to its respective flange. The screws can be adjusted to reduce the eccentricity of the drum.