Thermal transfer ink sheet and method of printing

Abstract

A thermal transfer ink sheet including a heat resistant support film, a first fusible ink layer disposed on the support film, an interlayer which will support the first ink layer in uniform layer condition during thermal printing and will still separate cleanly from the non-printed portion on the first ink layer and a second fusible ink layer on the interlayer. Several embodiments of the interlayer will maintain the first ink layer in uniform layer condition during thermal printing. The interlayer can be formed of: a material with a low melting point whose viscosity does not decrease substantially when its temperature is increased; a thin film of thermosetting resin; and a layer of material formed of minute grains or domains smaller than a pixel which will form a pixel sized layer support during thermal printing. To print with the thermal transfer ink sheet constructed in accordance with the invention, the exposed surface of the support film is selectively heated to transfer the interlayer and both fusible ink layers to the recording medium after the support film is stripped away. All the layers separate cleanly and the interlayer supports the printed portion of the first ink layer in layer condition to yield a uniform visible printed surface.