Evaluation, using EIS, of anticorrosive paints pigmented with zinc phosphate

Abstract

Due to their excellent corrosion inhibiting properties, both red lead and hexavalent chromate based pigments have been used in organic coatings for a long time, In spite of their widely recognised toxicity and the legal restrictions imposed on their use, they cannot be entirely elhninated from formulations even though there is an increasing trend towards reducing their content in anticorrosive paints used for industrial maintenance. Regardless of the many efforts that have been made to replace these toxic pigments, the replacment compounds that have been proposed have in only a few cases become as effective, as has been claimed. Accordingly such use has not generalised. It is perhaps a measure of the efficiency of the traditional pigments that they still held approximately 50% of the US market in 1990.