| 摘要 |
1,052,355. Brightening polyester fibres. J. R. GEIGY A.G. May 28, 1965 [May 29, 1964], No. 22782/65. Heading D1P. Fibres made from polymeric esters of terephthalic acid are optically brightened by impregnating them with an aqueous suspension of a mixture of optical brighteners containing no acid salt-forming groups and having a particle size less than 10Á and comprising a stilbene compound of the formula and at least one compound which is a derivative of coumarin, benzoxazole or napthalic acid imide, has an affinity to polyesters, forms colourless, blue fluorescent solutions and is free from stilbene groups, and then heating the impregnated fibres to a temperature of 180‹- 220‹C. The brighteners containing a coumarin ring may be derivatives of 3-phenyl-7-aminocoumarin preferably 3-phenyl coumarin compounds substituted in the 7-position by a 3- methyl-pyrazolyl-(l), naphtho-(1', 2' : 4, 5)- triazolyl-(2) or 4-chloro-6-diethylamino-1, 3, 5-triazinyl-(2) radicals suitable benzoxazoles are bis-benzoxazolyl-(2')ethylenes and -2, 5- thiophenes, and suitable naphthalic acid imides, are 4-alkoxy-naphthalic acid-N-methylimide and 4-acetamino naphthalic acid-N- butyl-imide. The particle size of the brighteners may be 1-5Á or less and may be present in a concentration of 0.3-5g per litre. The fine degree of distribution of the brighteners may be obtained by milling with sand in the presence of water and a dispersing agent, e.g. a condensation product of naphthalene sulphonic acid and formaldehyde, which may be present in an amount of 1/30th to 1/10th of the total weight of the mixture of brighteners. The aqueous suspension of the brighteners may also contain emulsifying agents, e.g. fatty alcohol polyglycol ethers such as stearyl alcohol polyglycol ethers having 8-10 ethyleneoxy groups, protective colloids, e.g. high polymeric polyacrylates or polyacrylamides and thickeners, e.g alginates, carboxymethyl cellulose and methyl cellulose, After impregnation the fibres may be squeezed out to a liquor content of 40-100% by weight, optionally dried and then heated. Fabrics comprising fibres of polymeric esters of terephthalic acid and cotton fibres may be brightened with an aqueous suspension which also contains a brightening agent for cotton, e.g. or may subsequently be treated with the brightener for cotton. The mixed fibre fabrics may be bleached with sodium chlorite or hydrogen peroxide prior to treatment with the brighteners or the brightener for cotton may subsequently be applied together with a hydrogen peroxide solution containing sodium silicate and sodium hydroxide. |
