| 摘要 |
1496337 Flourescent brightening compositions CIBA - GEIGY AG 17 Dec 1974 [19 Dec 1973] 54452/74 Heading DIP An aqueous solution contains 10 to 40% by weight of a quaternised flourescent brightener selected from a quaternised 2 - benzimidazol - 2 - yl benzofuron, a quaternised 5 - phenyl - 2 - benzimidazol - 2 - yl furan or an oxacyanine, i.e. a dibenzoxazole monomethine cyanine compound, the solution also containing either (a) an aprotic, water - soluble or - imiscible organic compound or (b) an acid having a pka of at least 3.5 and a water soluble or miscible organic compound. In case (a) the solution preferably contains 15 - 60% by wt. of the water soluble or -miscible compound 10 to 40% by wt. of water and 10 to 50% by weight of acid. In case (b) the solution preferably contains 20 to 70% by wt. of the aprotic water soluble or -miscible organic compound and 20 to 60% by wt. of water. Exemplified brighteners are in which X 1 is hydrogen or sulphomethyl and X 2 is methyl or benzyl. The water soluble or -miscible compound may be 2 - methylpentane - 2, 4 - diol, ethylene glycol monoalkyl ethers with 1 to 4 carbon atoms, e.g. ethylene glycol mono - n - butyl ether, polyglycols and ethers therrof, water soluble ketones and alcohols e.g. diacetone alcohol, urea, formamide or dimethyl formamide. The weak acid may be acetic acid. propionic acid, glycolic acid, maleic acid or lactic acid. The aprotic organic water soluble or -miscible compound may be propylene carbonate, ethylene carbonate, tetramethylene sulphone, dimethyl sulphone, dimethyl sulphoxide or gamma butyrolactone. The compositions are stable and some do not crystallise out even at -10‹C. |
