Thermal recording system
AssigneeBard Laboratories, Inc.
InventorKenneth J. Quast
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Abstract
Thermorecording sheet, thermorecording method and method of manufacture of a thermally responsive recording paper comprising a reversibly reduced cyclic polyketo compound such as hydrindantin and a thiuram compound having a sulfur chain linkage of at least two sulfur atoms.
Claims20
A thermally responsive recording sheet comprising a substrate and a thermally responsive coating on the substrate comprising in a reversibly reduced form, a cyclic polyketo compound, color reactive with amines, and an N-substituted thiuram polysulfide.
In a method for recording on a thermally responsive sheet employing selective thermal activation of an amine-polyketo color compound system to produce a visible mark, the improvement comprising conducting, upon said thermal activation, a redox reaction between a cyclic polyketo compound in reversibly reduced form and an N-substituted thiuram polysulfide to reductively decompose said thiuram polysulfide and to oxidize said reduced polyketo compound to provide, respectively, cyclic polyketo compound and reactive amine components of an amine-cyclic polyketo color compound system responsive to said thermal activation.
A method of manufacturing a thermally responsive recording paper, comprising, providing an aqueous coating dispersion of finely divided hydrindantin and finely divided N-substituted thiuram polysulfide in an aqueous solution or dispersion of a suitable water soluble or dispersable binder material, coating a base paper substrate with said aqueous coating dispersion, and drying said coated paper.
Dependencies are inferred from the claim text.