| 摘要 |
PURPOSE: To obtain a thermal transfer material for accurately coloring by using a croconium dye as a radiation absorbent in a donor unit for thermal diffusion-transfer imaging having a donor layer containing a thermally transferable coloring agent and the absorbent. CONSTITUTION: A donor element for the thermal transfer material or particularly a thermal diffusion-transfer imaging has a donor layer containing a thermally transferable coloring agent and a radiation absorbent. In this case, as the absorbent, a croconium dye is used. As the croconium dye, for example, a compound having a nucleus represented by a general formula separately described is selected, wherein A is independently a carbon ring, a heterocycle and a condensed ring or the other thermal group known in the technical art of a polymethine chemistry, and m is independently 0, 1 or 2. Thus, a co-transfer of the absorbent with the coloring agent is eliminated, a contamination of the image to be transferred is prevented, and the image is accurately colored. |
