The Wrinkling Behavior of Wool Fabrics—Conditions of Testing

Abstract

The effects of time, temperature, and humidity on wrinkle formation and recovery have been studied during the five distinct phases considered to control wrinkling behavior. Quantitative test data are readily influenced by the history of the fabric, by preconditioning, and by conditioning; the environmental conditions prevailing during all phases must be carefully controlled. Conversely, application of the empirical data now available allows considerable latitude in the choice of conditions of temperature, humidity, and time. Conclusions from earlier work indicating that it is advisable to change the temperature and/or humidity immediately before wrinkle insertion are reinforced by the present results.

Physical Ageing and Annealing in Fibers and Textile Materials

“…The level of ageing determines the wrinkling performance of a wool fabric [4]. The work reported in this paper now provides a basis for the level of fabric ageing to be applied to experimental measurements of fabric wrinkling behavior in order that such measurements relate directly to actual wearing conditions.…”

“…The de-ageing sequence given above has been compared to the treatment previously outlined for the multiple pleat tester [4], that is, wet pressing. We have previously shown [3] that the simple water soaking treatment at room temperature is an effective de-ageing procedure for wool fabrics and that the Hoffmanpressing of wet fabric samples is not essential to ensure complete de-ageing.…”

“…The principal aims of the work reported here are to quantify the level of wool fabric ageing that occurs in actual garment wear and to measure the influence of the important fabric and garment variables as well as the influence of ambient conditions. The influence of environmental conditions prior to mechanical deformation and recovery of woven wool fabrics (e.g., fabric wrinkling) has previously been investigated [4]. Wool fabrics that have been stored for a long period (aged at least several weeks) under stable conditions of temperature and relative humidity have been shown to exhibit better wrinkle recovery and lower stress relaxation rates under both constant and changing ambient environmental conditions [1,3].…”

“…Designers of wrinkle test methods [2,4] have been careful to specify standard preconditioning routines for wool and wool blend fabrics to be tested for wrinkling performance, e.g., (a) wet out fabric, remove surface moisture, then allow fabric to recondition at 65% RH and 20°C for 24 hours [2], or (b) wet out fabric in water containing a small amount of nonionic wetting agent at 20°C for 30 minutes, remove excess moisture, then steam press ( 10 seconds stream and then 10 seconds vacuum) the still damp (approximately twice the dry weight) fabric and allow 16 to 24 hours conditioning at 65% RH and 20°C [4]. This procedure is rtfertod to as &dquo;wet pressing.&dquo; These two preconditioning procedures eliminate the effects of any previous environmental history of a wool fabric, thus enabling the fabric wrinkling performance to be evaluated independent of fabric history.…”

Improvements in the Wrinkling Behavior of Annealed Wool Fabrics After Steam-Pressing

“…The wrinkle-recovery of wool fabric is determined largely by the extent of stress-relaxation that occurs during the wrinkling process [2,5] and is influenced by humidity and temperature as well as wrinkleinsertion and -recovery times [7].…”