| abstract |
Chromogenic compounds of colorless or lightly colored form are disclosed having the following structural formula: <IMAGE> wherein X represents an optionally substituted aminophenyl, indolyl, julolidinyl, kairolyl, piperidinophenyl, pyrrolidinophenyl, morpholinyl, carbazolyl or indolizinyl radical. The compounds of this invention are eligible for use in pressure-sensitive and heat-sensitive record materials and manifold marking systems. |