Hydrazine derivatives of phthalides and furopyridinones, methods for making and for using said compounds.

摘要

This invention relates to mono- and bis (aryl-and/or heteroaryl)-substituted-phthalazinones, phthalimidines, pyridopyridazinones and pyrrolopyridinones useful as color-forming substances, particularly in electrochromic recording systems, which are prepared by the interaction of a mono- or bis-substituted-phthalide or furopyridinone with a substituted or unsubstituted hydrazine.