| 摘要 |
1,159,219. Bleaching and brightening cellulose or synthetic polyamide fibres. J. R. GEIGY A. G. 7 Sept., 1967 [8 Sept., 1966], No. 40978/67. Heading D1P. Cellulose and synthetic polyamide textile fibres are chemically and optically bleached by applying .thereto a water soluble salt of chlorous acid in an aqueous acid liquor at raised temperature and drawing on to the fibres before or during the chemical bleaching with the salt of chlorous acid an optical brightener having the formula in which of Y 1 , Y 2 , Y 3 and Y 4 , one Y represents the sulphonic acid group and the other Y's represent hydrogen, and of Q 1 and Q 2 , one Q represents fluorine, chlorine or bromine and the other O represents hydrogen, or a salt thereof, e.g. an alkali metal, ammonium or amine salt thereof. The salt of chlorous acid may be an alkali metal chlorite and the pH of the bath thereof may be adjusted to about 3-5 by the addition of oxalic, formic, acetic, sulphuric or phosphoric acid or an acid phosphate. The bleaching baths may also contain wetting and dispersing agents, e.g. fatty alcohol sulphates, fatty acid alkanolamides or higher alkyl benzene sulphonates, salts of oxidising acids suitable for the passivation of iron apparatus, e.g. alkali metal nitrates or chlorates, and Glaubers salt. Cotton, regenerated cellulose and synthetic polyamide fibres may be treated. |
