Thermal transfer pressure method, dye transfer layers and process for their preparation, dye receiving layers and a thermal printing system.

摘要

This invention relates to tThermal dye transfer printing systems which are adapted for multiple-use printing modes wherein one dye transfer sheet is repeatedly used and which comprise a dye transfer sheet having, on a substrate, a dye transfer layer containing a sublimable dye and a binder resin and a dye receiving sheet having a dye receiving layer which has a diffusion rate of the dye smaller than the dye transfer layer. This is effective in suppressing a lowering of printing density owing to the increase in number of printing cycles using one dye transfer sheet. Alternatively, the dye transfer sheet is constituted such that the dye transfer layer is made of a least two sub-layers in which the concentration of the dye decreases from the sub-layer formed directly on the substrate toward the surface side of the dye transfer layer. The dye is invariably supplied from the higher concentration sub-layers to ensure full color printing with a remarkably increasing number of multiple-use printing cycles.