United States Patent Office Patented Sept
3,343,905 United States Patent Office Patented Sept. 26, 1967 2 their washing fastness improved to acceptable levels. 3,343,905 After-treatments of this sort are objectionable from the NYLON DYES Standpoint of both time and cost, but, until now have been James F. Feeman, Wyomissing, Pa., assignor to Crompton the best means available to the dyer for the production of & Knowles Corporation, Worcester, Mass., a corporar Washfast heavy dyeings on nylon. tion of Massacialsetts Other classes of dyes applicable to nylon are similarly No Drawing. Fied Oct. 20, 1966, Ser. No. 587,987 unsuited to production of washfast heavy dyeings. Dis 3 Claims. (C. 8-26) perse dyes are notoriously poor to washing fastness, even This application discloses and claims subject matter though they produce level dyeings with ease and of satis contained in my copending applications, Ser. No. 328,051, O factory depth. Their washfastness is not improved by filed Dec. 4, 1963, now Patent No. 3,305,539 and Ser. after-treatments to the same extent that is found with the No. 378,460, filed June 26, 1964, now abandoned. neutral dyeing acid dyes. Mordant dyes may be metallized This invention relates to dyes for nylon fibers, to a (notably chromed) on nylon by after-treatments with method of dyeing nylon fibers and to the products pro metal salts in acidic baths yielding dyeings of excellent duced by such process. fastness to washing, but the dyeing procedure is very dif Dyeing of nylon in heavy depths of shade with a high ficult to control to the degree necessary to enable the order of fastness to washing is an important technical matching of shades.
[Show full text]