A printing roller for a printing machine, e.g., for a flexographic printing machine, wherein the printing roller includes a rotary and longitudinal axis and an external surface, the external surface being substantially cylindrical and adapted for mounting a plate. The new feature of a printing roller according to the invention is that the external cylindrical surface includes at least one longitudinal groove, where the at least one longitudinal groove includes a geometry with one or more surfaces, the surface or surfaces lying within a circumscribed cylindrical surface for the external surface of the printing roller. In other words, this means that the longitudinal groove or grooves are cutouts in the form of milled or ground grooves in the external cylindrical surface itself on a printing roller.

A composite doctor blade chamber (1) for a doctor blade chamber system for rotary printing units, the doctor blade chamber (1) including a front side with an open channel (8), wherein the doctor blade chamber is made of two composite profiles, an open profile (30) with a front side and a back side and a closed profile (33) with a front side and a back side, wherein the front side (31) of the open profile is joined with the back side of the closed profile (35), whereby is achieved low weight and high strength, high corrosion resistance, a cleaning-friendly surface, less waste of ink, nice appearance and an improved working environment. In addition it is an object of the invention to provide a doctor blade chamber system with the above mentioned advantages where re placement of doctor blades can be performed faster, more easily and without use of tools.

A liquid transfer apparatus includes: rollers configured to transfer supplied liquid to a blanket cylinder; a roller holding device configured to detachably hold the rollers and perform a rotating operation to move any one of the rollers to a predetermined position facing the blanket cylinder; and a contact-separation unit configured to bring the roller held by the roller holding device and disposed at the predetermined position into and out of contact with the blanket cylinder.

Methods, systems, and apparatus for thermal transfer printing include a band of material comprising a polyimide film, the band and a thickness of the band are selected based on heat transfer characteristics through the band; a print roller or platen configured and arranged to support a substrate; a printhead configured and arranged to thermally transfer ink from the band of material to the substrate; a combined heating and re-inking system comprising a heated ink roller comprising a textured outer surface, wherein a first portion of the heated ink roller contacts the band to cause ink on the band to re-melt, flow and replace at least some of the portion of the ink transferred to the substrate previously before arriving at the printhead again for a next print, and a second portion of the heated ink roller receives new ink; and a control system that matches the band and substrate speeds.

Methods, systems, and apparatus, including medium-encoded computer program products, for thermal transfer printing include, in at least one aspect, a printing apparatus includes: a band capable of holding hot melt ink thereon; rollers configured and arranged to hold and transport the band with respect to a substrate; a printhead configured and arranged to thermally transfer a portion of the ink from the band to the substrate to print on the substrate; and a heating device configured and arranged to heat the band to cause ink on the band to re-melt, flow and replace at least some of the portion of the ink transferred to the substrate previously before arriving at the printhead again for a next print.

A chamber blade system maximizes ink flow at an anilox doctor blade by including a heating element adjacent the doctor blade to heat ink adjacent the blade. The heating element may be a heat strip next to an anilox doctor blade that heats the ink adjacent the doctor blade and temporarily reduces the ink viscosity to improve the flow of ink in the vicinity of the blade. Doctoring blades with a ceramic tip coating may be configured to allow a small amount of controlled ink flow through that can wet the lands thereby reducing the hydrodynamic back pressures and friction when trying to force the ink into anilox cells.

An imaging device can include an imaging drum to support a carrier fluid. A roller can remove a portion of the carrier fluid from the imaging drum. A fluid container can collect the carrier fluid from the roller. A fluid remover on the container can be used to remove the carrier fluid from the roller.

A doctor beam for use in a printing unit, e.g. a flexographic printing unit, wherein the doctor beam has a front side with a U-shaped channel, wherein the doctor beam is made of metal and includes a surface coating produced by Plasma Electrolytic Oxidation (PEO), the surface coating at least covering the U-shaped channel, and wherein the doctor beam further includes a non-stick ceramic coating, whereby is achieved the possibility of using metal for making doctor beams without risking their degrading, neither due to chemical impact of the applied inks/lacquers/primers nor due to the destruction of the surface coating by cleaning liquids. The invention also concerns a method for treating the surface of a doctor beam and use of a doctor beam.

Methods, systems, and apparatus, including medium-encoded computer program products, for thermal transfer printing include, in at least one aspect, a printing apparatus includes: a band capable of holding hot melt ink thereon; rollers configured and arranged to hold and transport the band with respect to a substrate; a printhead configured and arranged to thermally transfer a portion of the ink from the band to the substrate to print on the substrate; and a heating device configured and arranged to heat the band to cause ink on the band to re-melt, flow and replace at least some of the portion of the ink transferred to the substrate previously before arriving at the printhead again for a next print.

A device for printing on hollow bodies has a plurality of printing units each having a printing cylinder. At least one of the printing units has an inking unit having a chambered doctor blade that provides printing ink. The chambered doctor blade system has at least one ink pan and a doctor blade holder in a single assembly. The single assembly of the chambered doctor blade system is retained in the inking unit only on one side. The assembly of the chambered doctor blade system forms a cantilever arm on a side frame of the inking unit. The assembly of the chambered doctor blade system can be moved axially parallel to the anilox roller and can be removed from the inking unit by that movement.