Abstract
Three kinds of dyes were selected among the anthraquinone drivatives with different amino groups to investigate their spectroscopic characteristics and the effects of nitrogen dioxide on their fading. These dyes dissolved in tetrachloromethane were exposed to nitrogen dioxide standard gases by using a midget impinger. UV-VIS spectra were measured in appropriate intervals during the nitrogen dioxide exposure. The fading of these dyes by nitrogen dioxide was found to be rapid in the following order:
1, 4-diaminoanthraquinone > 1-aminoanthraquinone > 1-methylaminoantraquinone.
The relatively high reactivity of 1, 4 -diaminoanthraquinone is considered to be derived from two amino substitutent groups. However, it is not easy to understand the fact that 1-aminoan-thraquinone is more reactive to nitrogen dioxide than 1-methylaminoantraquinone from the standpoint of the basicity strength of amino groups.