Roylance, Abrams, Berdo & Farley
Bisfluoran chromogenic compounds, preparation thereof, and pressure-sensitive copy systems employing same
 A substantially colorless bisfluoran chromogenic material having the structural formula ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group; PA1 X and Y each represent a hydrogen atom, a halogen atom, an hydroxyl group, an alkyl group, a nitro group, an amino group, an acyl group, or a carboalkoxy group; PA1 Z represents an oxy radical, a carbonyl group, an alkylene group, an alkylidene group, a sulfonyl group, or a thio radical; and PA1 n represents an integer from 0 to 1. The bisfluoran compounds are produced by reacting a 4-dialkylamino-2-hydroxy-2'-carboxybenzophenone with a diphenol wherein the diphenol is unsubstituted in at least one of the positions ortho to an hydroxyl group in each of the phenyl rings. The bisfluorans are used in pressure-sensitive copy systems comprising a support bearing microcapsules containing the bisfluorans, alone, or in combination with other color-forming materials. 
Champion International Corporation
B C Y
B41M C09B Y10S
inventional inventional additional
Cheng H. David N.
Chang Vincent