Abstract: Polycarboxybenzenes esterified with certain partially fluorinated alcohols and with hydroxyl-containing organic radicals such as 2-hydroxyethyl, glyceryl and chlorohydryl or bromohydryl, leaving no free carboxy groups, when incorporated with PET or nylon fibers as by contact in a liquid medium, these compounds concentrate at the fiber surface especially if the fiber is annealed (heated without abrading above its T.sub.g). A relatively durable oil and water repellency is thus imparted to the fiber; which durability can be enhanced by contacting said compound in situ in the fiber with a polyepoxide or polyisocyanate.Alternatively, partially fluorinated N,N-disubstituted amides, esterified also with the same above-cited hydroxyl-containing organic radicals, can be used. The resulting fibers can be dyed, after or together with said treatment imparting repellency.

Abstract: Fluorinated poly-(C.sub.2 to C.sub.10) alkylene polyamides (especially alpha, omega-triazaalkanes) in which the endmost nitrogen atoms are acylated by fluorinated carboxylic acid groups and an interior nitrogen atom is acylated by a dibasic acid moiety of the group consisting of (C.sub.4 to C.sub.14) alkane dioic acid moieties and the thiocarbonic acid moieties --C(.dbd.O)S-- and --CS.sub.2 --; wherein per the invention, a radical is terminally attached to the acylating dibasic acid moiety, of the group --CH.sub.2 CH.sub.2 OH, --CH.sub.2 CH(CH.sub.3)OH, --CH.sub.2 CH(OH)CH.sub.2 X (X being halogen or --CN), or ##STR1## The compounds are amphipathic, behaving like surfactants when incorporated with nylon. They are prepared by broadly known methods of producing esters and thioesters of acids. The stain resistance of fibers incorporating these compounds can be improved as to durability and at least partially restored after abrasion of the fiber, by annealing.