| 摘要 |
1,201,719. Optically brightened filaments. J. R. GEIGY A.G. 24 July, 1968 [25 July, 1967], No. 35221/68. Heading B5B. [Also in Divisions C2 and D1] Wet-spun threads of polymeric or copolymeric acrylonitrile in the swollen condition are optically brightened by treatment with a compound of the formula wherein A represents an unsubstituted phenyl radical or a phenyl radical substituted by a non- ionic group or by a group which does not impart colour to the compound, R 1 and R 2 represent hydrogen or C 1-6 alkyl groups, R 3 represents hydrogen or an optionally substituted C 1-6 alkyl or alkenyl group, R 4 , R 5 and R 6 represent optionally substituted C 1-6 alkyl or alkenyl groups, cycloalkyl or aralkyl groups or R 4 and R 5 together with the N atom and optionally with the inclusion of oxygen, form a non-aromatic heterocyclic ring, or R 4 and R 3 together represent an alkylene group, X represents a C 1-6 alkyl group, an optionally substituted C 1-6 alkoxy or alkylthio group or an amino group -NR 7 R 8 where R7 represents hydrogen or an optionally substituted C 1-6 alkyl or alkenyl group and R 8 may take the same values as R 7 or, additionally, represent a cycloalkyl group or an unsubstituted phenyl radical or a phenyl radical substituted by a non-ionic group or by a group which does not impart colour to the compound, or R 7 and R 8 together with the N atom, optionally with the inclusion of oxygen, form a non-aromatic heterocyclic ring, Z represents an alkylene or alkylene-oxa-alkylene radical and Y- is the anion of a strong, colourless acid. The brightening treatment is preferably effected by passing the filaments prepared in an aqueous precipitation bath through an aqueous solution containing 0À01-0À5% by wt. of brightener. Examples 34 and 35 describe the production of poly-acrylonitrile/methyl acrylate filaments by spinning in a water/dimethyl formamide bath, treatment with a solution of an optical brightener and subsequent drying and stabilization. |
