Opacification: solving the fundamental problems

Abstract

This report describes some of the fundamental problems associated with the Opacification program in the Polaroid SX-70 photographic integral system. Phthalein dyes which at a pH of 14 absorbed over the visible spectrum, were stable in alkali for over a year, had pK a values above 13 and were immobile in the photographic system were synthesized to solve these problems.