Abstract: A dye donor, such as a transfer ribbon, comprises a supporting substrate and a relatively thick dye layer consisting of a dye dispersed within a dye binder. A heater, such as a modulated scanning laser beam, heats selected pixel regions of the ribbon and causes dye to diffuse from the heated regions to a receiver sheet and print a number of pixels thereon which build up to form an image. In order to allow the donor to be reused, it is passed between a pair of heated rollers to cause dye in the dye layer to diffuse to an even density whereby the regions depleted of dye during the print process are replenished. Instead of the replenishment dye coming from the body of the donor, it may be supplied by a separate source.

Abstract: Printing methods and apparatus for thermal transferring dye from a dye donor to a dye receiver wherein electromagnetic radiation such as a laser beam is applied through the dye receiver to effect dye transfer. Either or both of the dye donor and the dye receiver used with such printing methods and apparatus can be in the form of individual sheets or continuous ribbons and may be either stationary or moving. In various embodiments, the dye receiver is held between a convex surface of a rigid support plate and the dye donor during thermal transfer of dye. A variety of methods and devices for providing electromagnetic radiation and for transporting dye donors and dye receivers during printing are also disclosed.