Oxoindolizine and oxoindolizinium dyes and processes for their preparation.

摘要

Oxoindolizine and oxoindolizinium dyes are novel compounds useful in image formation such as in laser recording and reading. The dyes are formed by (1) the reaction of a cyclopropenone compound with a pyridine compound and optionally (2) by reaction of the product from (1) with a color-forming compound preferably in the presence of an oxidant.