| abstract |
A thermal recording material comprising a thermal recording layer which comprises a colorless or pale coloured dye precursor and a color developer with which the dye precursor reacts upon heating to develop a color, wherein the color developer comprises at least one bisurea compound of formula: <IMAGE> wherein X is a C1-C12 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a nitro group, a halogen atom or a hydrogen atom, Y is a divalent group of up to 30 carbon atoms, e.g. alkylene, arylene or <IMAGE> and Z is CH2, O, SO2 or NH and n is an integer of 1 or 2. The material may contain a dye which absorbs light and converts it with heat when the material is image-wise exposed to laser light. |