Patent ID: 7081910

Claim:
A thermal printer capable of preventing crease formation in successive dye transfer areas of a dye donor web that can cause line artifacts to be printed on a dye receiver during dye transfer from each dye transfer area to the dye receiver, said printer comprising: a thermal print head for heating a dye transfer area of the dye donor web sufficiently to effect dye transfer from the dye transfer area to the dye receiver, but not heating two opposite edge areas of the dye donor web alongside the dye transfer area sufficiently to allow dye transfer from the two edge areas to the dye receiver, so that crease formation can occur at least in respective regions of the dye transfer area adjacent the two edge areas; and a crease-preventing roller for supporting at least the dye transfer area and two edge areas, having an elastic cover layer that can be stretched towards coaxial opposite ends of said roller to spread at least the regions of the dye transfer area in which crease formation can occur in order to oppose crease formation, and having respective movable members moving to stretch said elastic cover layer towards said opposite ends of said roller.