Light and perspiration stability of triazinylstilbene fluorescent brighteners on cotton fabrics

Light and perspiration stability of triazinylstilbene fluorescent brighteners (TFBs) for cotton fabrics was investigated and many factors affecting the photo-fading of TFBs viz. substituent groups, artificial perspirations and their components were discussed. The experimental results indicated that the TFB with morpholine groups appeared to be the most sensitive one under simultaneous exposure to light and perspiration, whereas the TFBs containing sulfonic acid and diethanolamine groups exhibited the best stability. Among the three selected standards of artificial perspiration, the alkaline Association for Textile Technical Study standard perspiration retarded the photo-fading of TFBs on cotton fabrics remarkably. Furthermore, the study on the contribution of artificial perspiration components disclosed that the sodium salt played the predominant role in decelerating the photo-reaction of TFBs on cotton fabrics, while the influence of lactic acid was usually depended on two factors: the pH value and its reducibility.