Dyes for use in thermal dye transfer

Dye corresponding to the general formula (I):

• ##STR79## wherein:
• Z represents --CN, --COOR.sup.1 or --CONR.sup.2 R.sup.3 ;
• R.sup.1 represents hydrogen, an alkyl group, a substituted alkyl group, a cycloalkyl group, a substituted Cycloalkyl group, an aryl group, or a substituted aryl group;
• each of R.sup.2 and R.sup.3 (same or different) represents hydrogen, an alkyl group, a substituted alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an aryl group, a substituted aryl group, or R.sup.2 and R.sup.3 together represent the atoms necessary to complete a heterocyclic nucleus or a substituted heterocyclic nucleus;
• each of R.sup.4 and R.sup.5 (same or different) represents hydrogen, an alkyl group, a substituted alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an aryl group, a substituted aryl group, a heterocyclic ring, a substituted heterocyclic ring, SO.sub.2 R.sup.8, COR.sup.8, CSR.sup.8, POR.sup.8 R.sup.9, OR.sup.6, NR.sup.6 R.sup.7, SR.sup.6, or R.sup.4 and R.sup.5 together represent the atoms necessary to complete an aliphatic ring, a substituted aliphatic ring, a heterocyclic ring, a substituted heterocyclic ring;
• each of R.sup.6 and R.sup.7 (same or different) represents an alkyl group, a substituted alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an alkenyl group, a substituted alkenyl group, an aralkyl group, a substituted aralkyl group, an aryl group, a substituted aryl group, a heterocyclic group, or a substituted heterocyclic group, or R.sup.6 and R.sup.7 together represent the atoms necessary to complete a 5- or 6-membered ring;
• each of R.sup.8 and R.sup.9 (same or different) represents an alkyl group, a substituted alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an alkenyl group, a substituted alkenyl group, an aryl group, a substituted aryl group, an alkyloxy group, a substituted alkyloxy group, an aryloxy group, a substituted aryloxy group, an alkylthio group, a substituted alkylthio group, an arylthio, a substituted arylthio group, an amino group, a substituted amino group, a heterocyclic group, or a substituted heterocyclic group, or R.sup.8 and R.sup.9 together represent the atoms necessary to complete a 5- or 6-membered ring;
• and
• X represents a substituted nitrogen atom or a substituted carbon atom.