Transferring dyes for thermal printing: tri-cyano-vinyl aniline dyes

Abstract

Dyes are transferred from a carrier by sublimation/vaporization to plastic-coated papers by a process in which the dyes used are of the general formula (I) ##STR1## where A is D--N.dbd.N-- or ##STR2## R.sup.1 and R.sup.2 are each hydrogen, alkyl, alkoxy, alkylthio or halogen and R.sup.1 and R together may furthermore form a 5-membered or 6-membered heterocyclic ring, and R and R' independently of one another are each hydrogen, phenyl which is unsubstituted or substituted by methyl or methoxy, or C.sub.5 - or C.sub.6 -cycloalkyl or C.sub.1 -C.sub.6 -alkyl which is unsubstituted or substituted by C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -alkoxycarbonyl, C.sub.2 -C.sub.5 -alkanoyloxy, C.sub.1 -C.sub.4 -alkoxycarbonyloxy, C.sub.1 -C.sub.4 -alkoxy-C.sub.2 -or C.sub.3 -alkoxycarbonyloxy, hydroxyl, cyano, halogen, phenyl or C.sub.5 - or C.sub.6 -cycloalkyl, or ##STR3## is a 5-membered or 6-membered saturated heterocyclic ring where D is a radical of a diazo component of the thiophene, thiazole, isothiazole or 1,2,4-thiadiazole series and R.sup.3 is hydrogen or CN.In the process, the dyes (I) give strong dyeings which have good light fastness and are resistant to chemical substances.

Description

Claims

1. A process for transferring a dye from a carrier by sublimation/vaporization with the aid of a thermal printing head to a plastic-coated paper, said carrier employing a dye of the formula:

wherein R.sup.1 is C.sub.1 -C.sub.4 -alkoxy, and R.sup.1 is phenyl which is unsubstituted or substituted by methyl or methoxy, or is C.sub.1 -C.sub.6 -alkyl which is unsubstituted or substituted by C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -alkoxycarbonyl, C.sub.2 -C.sub.5 -alkanoyloxy, C.sub.1 -C.sub.4 -alkoxycarbonyloxy, C.sub.1 -C.sub.4 -alkoxy-C.sub.2 - or C.sub.3 -alkoxycarbonyl, hydroxyl or cyano.

2. The process as claimed in claim 1, wherein R.sup.2 is C.sub.1 -C.sub.4 alkyl which is unsubstituted or substituted by hydroxyl or cyano, or R.sup.2 is C.sub.1 -C.sub.4 -alkoxy-C.sub.2 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxycarbonyl-C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -alkoxycarbonyloxy-C.sub.2 -C.sub.4 -alkyl.

3. The process as claimed in claim 1, wherein R.sup.1 is methoxy.

4. The process as claimed in claim 2, wherein R.sup.1 is methoxy.

5. The process as claimed in claim 1, wherein R.sup.2 is C.sub.1 -C.sub.4 -alkyl, cyanoethyl, hydroxyethyl, C.sub.1 -C.sub.2 -alkoxyethy, C.sub.1 -C.sub.4 -alkoxycarbonyl-C.sub.2 -C.sub.3 -alkyl or methylphenyl.

6. The process as claimed in claim 3, wherein R.sup.2 is C.sub.1 -C.sub.4 -alkyl, cyanoethyl, hydroxyethyl, C.sub.1 -C.sub.2 -alkoxyethyl, C.sub.1 -C.sub.4 -alkoxycarbonyl-C.sub.2 -C.sub.3 -alkyl or methylphenyl.