Beck Dyeing Conditions Impact the Wear Performance of Nylon 66 Carpets Inserted with Low-Melt Polyamide Yarns

Abstract

Inserting a lower melting polyamide yarn between plies of nylon 66 yarn improves the appearance retention (AR) of carpet subjected to foot trafficking. However, the severe conditions associated with a commercial Beck dyeing process—water temperatures held close to the boil for several hours and unremitting physical rubbing of the heavy, wet surface—affect wear performance. Because Beck dyeing is preferred for contract carpet constructions, i.e., for use in schools, airports, hotels, hospitals, etc., where wear performance is of paramount importance, a low-melt inserted carpet’s ability to retain its improved wear performance following the rigors of dyeing raises important questions. A gas chromatographic method is developed to quantify the amount of insert yarn present in these carpets. Measurements taken from carpets sampled both before and after the Beck dyeing show that the loss of low-melt polyamide with dyeing is minimal. While these inserted carpets exhibit poorer AR performance under the extreme dye conditions of temperatures and dwell times, they outperform controls lacking the insert yarns. The slight performance deterioration likely results from a combination of redistribution of the low-melt material and the continual surface brushing during the dyeing operation.