Patent ID: 8907995

Claim:
A roll-fed duplex thermal printing system, comprising: a supply roll of thermal imaging receiver having dye receiving layers on first and second sides of a substrate; a printing path; a turning mechanism including a turn roller and a guide positioned around the turn roller; a diverter having a first position and a second position, wherein when the diverter is in the first position thermal imaging receiver is directed from the supply roll into the printing path, and when the diverter is in the second position the thermal imaging receiver is directed from the printing path into the turning mechanism; a thermal printhead positioned along the printing path; a donor ribbon feeding from a donor supply roll past the thermal printhead to a donor take-up roll, the donor ribbon including one or more donor patches, each having a respective donor material; a cutter positioned between the printing path and the turning mechanism; and a printer controller that controls components of the thermal printing system to perform the following sequence of operations: positioning the diverter into the first position; feeding the thermal imaging receiver from the supply roll into the printing path such that the first side of the thermal imaging receiver is oriented to face the thermal printhead; moving the thermal imaging receiver and the donor ribbon past the thermal printhead, during which time the thermal printhead applies heat pulses to transfer colorant from the donor ribbon onto the first side of the thermal imaging receiver, thereby printing a first-side image; using the cutter to cut a portion of the thermal imaging receiver including the printed first-side image from the supply roll; positioning the diverter into the second position; feeding the cut thermal imaging receiver from the printing path into the turning mechanism where the cut thermal imaging receiver is transported around the turn roller; feeding the cut thermal imaging receiver from the turning mechanism back into the printing path such that the second side of the thermal imaging receiver is oriented to face the thermal printhead; moving the cut thermal imaging receiver and the donor ribbon past the thermal printhead, during which time the thermal printhead applies heat pulses to transfer colorant from a donor ribbon onto the second side of the thermal imaging receiver, thereby printing a second-side image; and feeding the cut thermal imaging receiver out of the printing system.