Retardation of the Photoyellowing of Untreated Wool and Wool Treated with Fluorescent Whitening Agents by the Action of Reducing Agents

Different chemically treated wools have been exposed to radiation in the presence of different aqueous reductive bleaching agent solutions. It was observed that thiourea dioxide (TDO) gave the best performance and, in the case of wool serge, led to fabric having a better light fastness. Biphenols (models for dityrosine) have also been padded onto wool and exposed to light in the wet state to mimic the photoyellowing of dityrosine