A SUCCESSFUL WEAVING TRIAL WITH A SIZE-FREE COTTON WARP

Authors: Sawhney, Amar; Price, John; Calamari Jr, Timothy

Submitted to: Indian Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/23/2003
Publication Date: 6/1/2004
Citation: Sawhney, A.P., Price, J.B., Calamari Jr, T.A. 2004. A successful weaving trial with a size-free cotton warp. Indian Textile Research Journal. 2004. 29:17-21.

Interpretive Summary: Production of woven cotton fabrics involves an essential process of warp yarn sizing (coating) to assist efficient weaving. However, fabric woven from a sized warp must be desized to completely remove all of the size formulation used. Both warp sizing and subsequent fabric desizing are centuries-old textile processes that are very complex, costly, and environmentally sensitive. This is because of the wastage of expensive chemicals, energy and water involved in these two processes and also because of waste water treatment that is mandated by the Environmental Protection Agency (EPA). The textile industry wants to reduce and preferably eliminate warp sizing. This would automatically reduce or eliminate fabric desizing and ultimately lower production costs and environmental risks. Scientists at SRRC have developed a multi-pronged research approach to try to eliminate warp sizing and achieve efficient size-free weaving. The approach basically consists of: 1) improving greige yarn structure and quality; 2) improving warp preparation without sizing; and 3) minimizing yarn abrasion during weaving. Results of a preliminary weaving trial recently conducted with a size-free warp on a commercial weaving machine operating under mill-like conditions have been extremely encouraging. For the first time ever, we were able to efficiently weave without a single yarn failure more than 45 meters of a 100% cotton twill fabric of a relatively open construction. Additional trials with different materials and machines have been planned to gain a fundamental understanding of size-free weaving and its potential problems. Success in size-free weaving would yield significant economic, technological and environmental benefits to cotton textile industry.

Technical Abstract: An American Upland combed cotton was rotor spun to produce a yarn as strong, uniform and smooth as possible, using customary mill equipment. A loom beam was prepared by simply washing the warp yarn in boiling water containing a mild detergent and a wetting agent, i.e., without using any conventional sizing agent. The yarn was successfully and efficiently woven on a shuttle loom into a 2/1-twill fabric of a relatively open construction. It was observed during weaving that hairiness of the warp (yarn) increased visibly as the warp raced forward towards the cloth fell. The hairiness particularly was pronouncedly visible in the shed near the cloth fell. This probably was due to the shed-depth in the region being low and the two components orlayers of the shed being in close proximity to each other. Yet, more than 45 meters of fabric were woven at three different pick densities without incurring a single warp yarn failure or breakage, which is very encouraging. Based on the overall good performance of the size-free warp in this preliminary weaving trial, it appears that weaving of a singles cotton yarn, without the age-old tradition of warp sizing, may indeed be feasible at least for certain types of yarns, fabrics and weaving machinery. With planned weaving trials with different processing materials, equipment, procedures and conditions, we expect to enhance commercial prospects of size-free weaving of typical mill yarns on classical mill equipment.