Abstract: A fiber-forming polyamide composition contains a fiber forming polyamide and a sulfonated polyester concentrate, the concentrate disabling and dye sites in the polyamide so that fibers formed from the composition will have enhanced stain and soil resistance. The sulfonated polyester concentrate contains a reagent, preferably an alkali metal salt of 5-sulfoisophthalic acid, and thermoplastic polyester, preferably one or more of PET, PTT, PBT, PETG and poly(ethylene terephthalate-co-isophthalate).

Abstract: An on-line color monitoring and control system and method includes feeding of colorant in a given amount or ratio in order to achieve a desired color of a product. The system and method described here achieve reliable on-line color control of synthetic fibers, single moving yarn (or fiber) or a collection of moving fibers. The color characteristic of the product is sensed and processed to generate a control signal for adjusting the amount of colorant being fed. Color measurement takes place either prior to or after spooling of the product.

Abstract: A composition for producing acid dye stain-resistant fibers includes a fiber-forming polymide, a polymer and a masterbatch concentrate which itself includes a reagent and a carrier. The reagent can be an alkal metal, alkaline earth metal or transition metal salt of 5-sulfoisophthalic acid. The carrier can be (A) a terpolymer of an alpha-monoolefin, ethylene-.alpha.,.beta. unsaturated carboxylic acid ester and an internal anhydride of an ethlenically unsaturated carboxylic acid. It can alternatively be (B) a semi-crystalline thermoplastic polyester, (C) a semi-crystalline thermoplastic polyamide, or mixtures of (B) and (C). The polymer in the composition can be (A) and mixtures of (A) and (B) and/or (C).

Abstract: In a method of producing poly(trimethylene terephthalate) yarn from PTT chip which has been extruded through a spinneret into filaments and coated, the coated filaments are passed between an unheated feed roll and a tension roll to tension them without causing permanent stretching, and then are passed from the tension roll to a heated draw roll to draw the filaments in a single draw step to a draw ratio of 1.25 to 4.0 and to heat them to a temperature between their glass transition temperature and their crystallization temperature.