Diazarhodamine-lactones, their manufacture and their use as dye intermediates for copying processes

Abstract

New diazarhodamine-lactones of the formula ##STR1## where R.sup.1 is hydrogen or alkyl of 1 to 4 carbon atoms, R.sup.2 is alkyl of 1 to 4 carbon atoms, unsubstituted phenyl or phenyl substituted by one or two alkyls of 1 to 3 carbon atoms, chlorine and/or bromine, R.sup.3 and R.sup.4 independently of one another are hydrogen, alkyl of 1 to 7 carbon atoms, cycloalkyl of 5 to 7 carbon atoms, phenylalkyl of 7 to 10 carbon atoms or alkoxyalkyl of a total of 3 to 8 carbon atoms, or the group ##STR2## is a 5-membered, 6-membered or 7-membered saturated heterocyclic ring or a 6-membered saturated heterocyclic ring which additionally contains an --O--, --S-- or --N--group, wherein R.sup.6 is hydrogen, methyl or ethyl and R.sup.5 is unsubstituted phenyl or phenyl substituted by alkyl of 1 to 3 carbon atoms, methoxy, chlorine or bromine. The lactones (I) exhibit improved stability and therefore do not stain coated paper. On papers coated with acid receptive layers, copies which instantly exhibit their full depth of color are obtained.

Dependencies are inferred from the claim text.