Novel degradation mechanism for triarylmethane dyes: Acceleration of degradation speed by the attack of active oxygen to halogen groups

We studied triarylmethane dyes using LC/MS and UV/VIS spectrometry and demonstrated that they undergo several degradation mechanisms depending on their chemical structures, thus leading to specific degradation rates and colour fading. In particular, we found that Basic Blue 1 (BB1) shows significantly fast decolourization. We suggest a new specific degradation mechanism for BB1 that arises from photogenerated center dot OH radicals from oxygen in air. (C) 2015 Elsevier Ltd. All rights reserved.