Abstract: This invention discloses the improved method of making nylon cationic dyeable whereby the soluble lithium, magnesium or calcium salt of a sulfonated polystyrene copolymer is added, to provide improved lighfastness and ozone resistance over conventional cationic dyeable nylon.

Abstract: This invention discloses the improved method of making nylon cationic dyeable whereby the soluble lithium, magnesium or calcium salt of a sulfonated polystyrene is added, to provide improved lightfastness and ozone resistance over conventional cationic dyeable nylon.

Abstract: It has been suggested that a high strength polycaproamide fiber having excess number of carboxyl end groups over amino end groups can be produced by melt spinning a polymer prepared by polymerizing e-caprolactam and reacting the polymer with a dibasic carboxylic acid containing at least six carbon atoms. However, with incorporation of this dicarboxylic acid reactant in continuous operation, serious problems have been encountered in melt-spinning of the polymer due to the frequent occurrence of "nubs" or enlarged places in the extruded polyamide filament. It has now been found that the occurrence of said nubs in the fiber can be greatly reduced by utilizing certain cyclic tetracarboxylic acid dianhydrides and reacting the dianhydride at the end of the polymerization. Moreover, dyeing properties of the fiber may be more readily controlled.

Abstract: It has been suggested that a high strength polycaproamide fiber having excess number of carboxyl end groups over amino end groups can be produced by melt spinning a polymer prepared by polymerizing e-caprolactam and reacting the polymer with a dibasic carboxylic acid containing at least six carbon atoms. However, with incorporation of this dicarboxylic acid reactant in continuous operation, serious problems have been encountered in melt-spinning of the polymer due to the frequent occurrence of "nubs" or enlarged places in the extruded polyamide filament. It has now been found that the occurrence of said nubs in the fiber can be greatly reduced by utilizing certain cyclic tetracarboxylic acid dianhydrides and reacting the dianhydride at the end of the polymerization. Moreover, dyeing properties of the fiber may be more readily controlled.

Abstract: A method of treating polycarbonamide fiber, such as nylon 6 yarn for carpets, has been discovered to increase dye fastness when the dyed fiber is exposed to ozone. The method is coating the fibers with a tertiary amine, or a substituted piperidine, morpholine, or piperazine compound. The compound must contain at least one moiety of straight or branched chain alkyl, alkenyl or aralkyl containing 6 to 24 carbon atoms.

Abstract: When from about 0.4 percent to about 3 percent of an alkanolamine such as: ##EQU1## where R is an alkylene of 1 to 13 carbon atoms, an aralkyl such as xylylene, or cycloalkyl, R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are H, alkyl of 1-2 carbon atoms or phenyl wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 can be the same or different, is coated on nylon fiber, improved dyefastness is achieved when the fiber is exposed to ozone.

Abstract: When from about 0.4% to about 5% of tertiary amines ##EQU1## WHERE R is an alkyl radical of 8-25 carbon atoms, R' is an alkylene radical of 2 to 10 carbon atoms, R" and R"' are hydrogen, a phenyl, or an alkyl radical of 1 to 3 carbons, but where R" and R"' are not both hydrogen, and x, y, and z are each at least 1 (x+y) is not greater than 6, preferably 2, and (x+y+z) is not greater than 9, preferably 3, are coated on nylon fiber, or are added to the dyebath, improved dyefastness is achieved compared to an untreated dyed nylon fiber when this fiber is exposed to ozone.