Patent ID: 7635660

Claim:
A thermal imaging member comprising: (a) a substrate having first and second opposed surfaces; (b) at least first, second and third image-forming layers carried by said first surface of said substrate, said first image-forming layer having a higher activation temperature than said second image-forming layer, and said second image-forming layer having a higher activation temperature than said third image-forming layer; (c) one or more spacer layers providing a time delay positioned between a first pair of image-forming layers, said first pair of image-forming layers consisting of said first and said second image-forming layers; and (d) one or more spacer layers providing a different time delay positioned between a second pair of said image-forming layers, said second pair of image-forming layers comprising said third image-forming layer; wherein the thickness of the one or more spacer layers positioned between said first pair of image-forming layers is less than the thickness of the one or more spacer layers positioned between said second pair of image-forming layers, each of the different time delays being a function of the respective thicknesses and usable for defining printing regions for colors to be formed.