| 摘要 |
539,566. Resinous condensation &c. products ; dyeing and bleaching; artificial filaments, films &c. MATHIESON ALKALI WORKS. May 6, 1940, No. 8145. Convention date, June 23, 1939. [Classes 2 (ii), 2 (iii) and 15 (ii)]' A solid resinous body composed of a synthetic linear condensation polymer capable of being- drawn into fibres with longitudinal orientation of the micelles, is subjected to treatment with an aqueous solution containing chlorite ions so as to remove discoloration and to increase its ability for being dyed. The polymer may be a polyamide obtained from a diamine and a dibasic acid or an amide-forming derivative of such acid, a polyamide obtained from an amino acid such as 5-amino caproic acid, a polymerization product of hexadecamethylenedicarboxylic acid and trimethylene glycol, a polyanhydride derived from a dibasic acid such as adipic or pimelic acid, or a polyesterproduced from a dibasic acid in presence of a diamine. A polyamide obtained from hexamethylene diamine and diphenic, adipic, or sebacic acid may be used. The polymer may be in the form of filaments, fabrics, bristles, sheets, ribbons, rods, tubes, or other shaped article. The treatment enables dyestuffs to penetrate the polymer more uniformly and to give a brighter and more uniform finish. Thechlorite solution is preferably used in acidcondition since under this condition the strength of the article treated is not appreciably reduced and in many cases is increased. If the chlorite solution is used in alkaline condition it is preferable to have hypochlorite ions present also. Bleaching is facilitated by including in the acid chlorite solution a small proportion of a synthetic detergent such as sodium lauryl sulphate, sodium 2-methyl pentane-4-sulphate, sodium sulphoethyl methyl lauramide, sodium sulphoethyl myristate, sodium diamyl sulphosuccinate, sodium decyl benzene sulphonate, and sodium hexadecyl sulphonate. The chlorite solution may be obtained by dissolving sodium chlorite in water, diluting to the required strength and adding acid or alkali to give the required pH value. Acetic acid, mineral acids, or alkali metal hydroxide, may be used. The treatment may be effected under acid conditions at elevated temperature. The use of a syntheticdetergent tends to bring about an increase in the tensile strength. If desired the materials may be subjected to treatment with an alkaline aqueous solution of sodium hypochlorite and then, without washing, to a treatment with sodium chlorite solution.
|
