Color-changing indoline-heterocyclic compounds

Abstract From the Canadian patent

The invention relates to apparatus for containing color changing compounds. The compounds are represented by the formula:, (1), wherein Q represents a benzene ring with or without a second fused benzene ring and/or at least one ring substituent selected from the group consisting of lower alkyl lower, alkoxy, halogen carboxy, carboalkoxy nitro, non-substituted-, amino, mono-alkyl substituted-amino di-alkyl substituted-amino, substituted-phenyl amino non-substituted-phenyl amino, substituted-phenoxy amino non-substituted-phenoxy amino, acetoamino low alkoxy carbonyl, cyano, substituted-phenyl non-substituted-phenyl, substituted-di-lower alkyl and, substituted-di-lower alkoxy; R1 and R2 are …