Abstract
The paper electrophoresis of twenty water soluble coal tar dyes permitted for food was studied by the Whatman No. 1 filter paper immersed in n-hexane as a cooling agent, with twelve electrolytic solutions at pH 3.011.6, under the conditions of 3, 000 volts and 30 minutes migration. The spot forms and the migration distances were largely influenced by the pH of the electrolytic solutions, and could be classified into several groups by the chemical constitutions of the dyes.
The selection of suitable electrolytic solutions enabled the identification of the twenty water soluble coal tar dyes and also the discrimination of the main and the subsequent dyes.
