摘要 |
Thermal transfer ribbons derived from aqueous-based coating formulations which do not require the application of a separate backcoat to the substrate. Backcoatings are self-generated on the untreated side of the substrate when the untreated side of the substrate contacts a remote portion of the top surface of the thermal transfer layer. The thermal transfer ribbons which self-generate backcoats comprise a flexible substrate and a thermal transfer layer which contains a water-soluble silicone block copolymer with blocks of silicone resin and water-soluble polymer. The water-soluble silicone block copolymer migrates to the top surface of the thermal transfer layer and generates a backcoat on the opposite surface of the substrate when the ribbon is wound such that the untreated surface of the substrate contacts a remote portion of the top surface of the thermal transfer layer. Embodiments which incorporate both a water soluble silicone block copolymer and hydrophobic siloxane liquid or gum in the thermal transfer layer, for migration, are included.
|