Thermal transfer printing process using a mixture of reducing agents for image-wise reducing a silver source
AssigneeAgfa-Gevaert
InventorsGeert Defieuw, Wilhelmus Janssens, Jean-Marie Dewanckele
Life of this patent
Estimating the term…
Abstract
The present invention provides a donor for use in thermal transfer printing. The donor element comprises on a support a donor layer comprising a binder and a mixture of at least two thermotransferable reducing agents capable of reducing a silver source to metallic silver upon heating. The donor element is image-wise heated while being in contact with an image receiving material comprising a thermoreducible silver source. By using a mixture of reducing agents crystallization is reduced and the obtained images exhibit an increased density and a more neutral grey hue.
Claims3
A thermal imaging process comprising, in order, the steps of:
- a) bringing a donor layer of a donor element into face to face relationship with a receiving layer of a receiving element to obtain an assemblage,
- b) image-wise heating the assemblage, thereby causing image-wise transfer of an amount of a plurality of thermotransferable reducing agents to said receiving element in accordance with the amount of heat supplied,
- c) separating said donor element from said receiving element, and
- d) overall heating said receiving element, wherein
- (i) said donor element comprises on a support (a) a donor layer comprising a binder and a mixture of said plurality of thermotransferable reducing agents which are capable of reducing a silver source to metallic silver upon heating, and (b) on a side of the support opposite a side comprising said donor layer, a heat-resistant backing layer, and
- (ii) said receiving element comprises said receiving layer on a support, said receiving layer comprising a silver source which is capable of being reduced by means of heat in the presence of a reducing agent.
Dependencies are inferred from the claim text.