DYE DONATING ELEMENT HAVING FLUORESCENT 7- AMINO COUMARIN

摘要

PURPOSE: To obtain a fluorescent material useful for a continuous gradation system and having a vapor pressure capable of moving from a donor element to a receptor element by itself to be diffused, by disposing a layer containing a 7-aminocoumarin compound which is represented by a specific formula and which is a colorless fluorescent material, on a surface of a support. CONSTITUTION: After an image picked up by a color video camera is converted into electric signals to be transmitted to a thermal transfer apparatus, the image is printed by a dye donor element and a dye receptor element, both being adjacently set, in a thermal transfer system. In this case, the dye donor element is formed by disposing a specific layer on the surface of a support and a slipping layer containing a lubricant on the rear thereof. The specific layer disposed on the surface of the support is formed by dispersing a 7- aminocoumarin compound which is a colorless fluorescent material and which is represented by a general formula shown in a separate paragraph, in a polymeric binder which is not thermally transferred. In the formula, X, Y and R1 , R2 each independently represents hydrogen, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or others.