Syntheses of Phenylpyrazolone Derivatives. IX

Notation of Phenylpyrazolone-azomethine Derivatives on C. I. E. Color Chart

Abstract

Attempts were made to indicate the color of 39 kinds of phenylpyrazolone-azomethine derivatives by the color chart of International Committee on Illumination, a standard method for the indication of colors, by measuring spectral transmittance. Calculation of trichromatic coefficient was made by the weight ordinated method, using the standard light source C, of the International Committee on Illumination, and considerations were made on the relationship between the dominant wave length obtained and chemical structure of the methine molecule. The effect of various substituents on the dominant wave length agreed with results reported previously, and the relationship between purity and brightness was found to be as shown in Fig. 4.