Fluorescent day-time luminous colours - contg. fluorescent dyes and reducing cpds added to prevent oxidative bleaching

摘要

Reducing cpds. are added to fluorescent dyes used as daylight luminous paints or colours. Used for marking fluids or inks for marking special passages in written texts. Oxidising bleaching of dyes, by air-O2 combined with daylight, is overcome. Reducing additives may be sulphurous acid derivs. e.g. Na2SO3, NaHSO3. Na dithionite, rongalite, glyoxal-NaNHSO3; or hydrazine and hydroxylamine and their sulphate or chloride salts.