Thermal transfer dye-donor element comprising a substrate having a microstructured surface

摘要

A novel thermal transfer donor element comprises, in order (a) a microstructured substrate having a surface (14) with randomly-positioned discrete protuberances of varying heights and shapes; (b) a black metal layer (16); (c) a gas-producing polymer layer with a thermally available nitrogen content of above 10 wt.%; and (d) a thermal mass transfer material in or over layer (c). Also claimed is an element in which layer (c) is omitted and (d) is over layer (b). The substrate (12) is transparent, with protuberances of height 10-1500 nm sepd. by distances of 3-500 nm. The black metal layer (16) has a transmission optical density of at least 0.3 (esp. at least 0.8) and a thickness of 0.01-1 microns and is of a mixt. of metal and metal oxide (e.g. obtd. as per US4430366) or of black Al, black Sn or black Ti.