Image transfer for liquid electro-photographic printing
AssigneeHewlett-Packard Development Company, L.P.
InventorsPeter Nedelin, Mark Sandler
Life of this patent
Estimating the term…
Abstract
In one example, an LEP printer includes a belt rotatable in a loop, a series of multiple printing units along the belt each to apply an LEP ink color separation to the belt, a first heater to dry the color separations on the belt to a molten film at a drying temperature, a second heater to heat the molten film on the belt to a transfer temperature higher than the drying temperature, and a pressure roller near the belt to press a printable substrate against the belt at a nip between the pressure roller and the belt.
Claims13
An LEP printer comprising:
- a belt rotatable in a loop;
- a series of multiple LEP printing units along the belt each to apply an LEP ink color separation to the belt;
- a first heater to dry the color separations on the belt to a molten film at a drying temperature;
- a second heater to heat the molten film on the belt to a transfer temperature higher than the drying temperature by a beam of light having an exposure time of 2 to 3 milliseconds;
- and
- a pressure roller near the belt to press a printable substrate against the belt at a nip between the pressure roller and the belt, wherein the second heater is located before the pressure roller.
An LEP printer, comprising:
- a belt rotatable in a loop;
- a series of multiple printing units along the belt each to apply an LEP ink color separation to the belt;
- a series of multiple first heaters along the belt, each first heater having a first intensity to dry the color separations on the belt to a molten film at a drying temperature;
- a second heater having a second intensity greater than the first intensity to heat the molten film on the belt to a transfer temperature higher than the drying temperature;
- a pressure roller near the belt to press a printable substrate against the belt at a nip between the pressure roller and the belt;
- and
- a controller programmed to:
- rotate the belt;
- and turn off some of the first heaters based on a density of the color separations on the belt.
An LEP printing process, comprising:
- rotating an intermediate transfer belt in a loop;
- and
- during a single rotation of the belt loop:
- gathering multiple LEP ink color separations together on the rotating belt;
- drying the color separations on the rotating belt to a molten film at a drying temperature;
- then heating the molten film on the rotating belt to a transfer temperature greater than the drying temperature by a beam of light having an exposure time of 2 to 3 milliseconds;
- and
- within 30 ms after heating the film on the rotating belt to the transfer temperature, transferring the film from the rotating belt to a printable substrate, wherein the heating is performed at a location on the intermediate transfer belt before the transferring.
Dependencies are inferred from the claim text.