| abstract |
Derivs. of formula (I): (where R is H, Cl, Br, CHO, COCH3, COOH or a residue of formula (Ia) are prepd. by reacting 9,10-phenanthroquinone monoimine (II) with a 5-substd. furfural in which the 5-substituent is H, CL, Br, CHO, COCH3 or COOH in the presence of piperidine in an organic solvent at the boiling point of the reaction mixture and subsequently removing the solvent. (I) are useful as luminophores for use in luminescence microscopy, in non-destructive testing of materials, as optical brightening agents, and in the production of luminous paints. The spectral range of the luminescence of (I) extends from violet to greenish vlue. |