Thesis Details

Thesis Title: A quantitative method of measuring yarn bulk for air-jet textured yarns
Thesis Author: Ronald "Ronny" Edward Grindle, Jr.
Abstract: Researchers have documented numerous measurement techniques for characterizing air jet textured yarns and have suggested improvements in these techniques. The measurements include loop size and frequency, physical bulk, instability, and shrinkage. However, most of these tests leave much to be desired in that they are laborious, time-consuming, and largely subjective. In contrast to these methods, Lawson-Hemphill, Inc. recently developed the Electronic Inspection Board (BIB) as an electronic instrument for characterizing yarn. For this research, 54 unique conditions of core-and-effect air jet textured yarns were produced by varying number of filaments per yarn, draw temperature, effect yarn overfeed, and air pressure. Data were analyzed to determine the effects of these process parameters on the following properties: package density ratio, fabric thickness, DuPont instability, hot-water shrinkage, depth of shade, and fabric appearance. In addition, loop size and frequency were determined for each condition using the EIB, and the reliability and validity estimates of this test method were established with these data. The results indicate that the test method developed in this thesis is both reliable and valid for the measurement of bulk for air-jet textured yarn.