Synthetic yarn with heat-activated binder fiber

A carpet comprising face fiber produced from a twist set yarn, wherein said yarn comprises:

• (a) at least one base fiber selected from the group consisting of polyester, nylon 6 and nylon 66, and
• (b) 1-12 weight percent (based upon the weight of said yarn) of a heat activated binder fiber which is derived from a mixture of:
• (i) 50 to 85 wt. % caprolactam, based upon the weight of the mixture;
• (ii) 0 to 40 wt. % hexamethylenediamine adipate or a combination of hexamethylenediamine and adipic acid, based upon the weight of the mixture;
• (iii) optionally, 5 to 50 wt. % of a component selected from the group consisting of hexamethylenediamine dodecanedioate, a blend of hexamethylenediamine and dodecanedioc acid, hexamethylenediamine azeleate, a blend of hexamethylenediamine and azelaic acid, hexamethylenediamine sebacate, a blend of hexamethylenediamine and sebacic acid, hexamethylenediamine terephthalate, and a blend of hexamethylenediamine and terephthalic acid;
• and
• (iv) a chain terminator selected from at least one of the group consisting of a fatty acid and a fatty amine, wherein said fatty acid or fatty amine includes at least 14 carbon atoms;
• said yarn having been heated so that said binder fiber is melted sufficiently so that it is capable of flowing and then cooled to solidify said melted binder fiber material such that intersecting points of said base fiber are bonded by said melted binder fiber material.