Changes of physical properties of Lyocell fabrics after repeated home laundering were investigated with the KES-FB system. In the case of washing with an alkalescent detergent and without a washing net, the bending and shearing properties of Lyocell fabrics increased remarkably after repeated laundering. The dry fiber diameters after the alkalescent washing were 1.1 times that of the original fiber, and then such distortion had influence on the slip resistance among yarns. Resilience of compressional property of Lyocell fabric increased markedly with increasing the number of home launderings, indicating the different results obtained from the washing of knitted fabric for undershirts. When Lyocell fabrics were washed with a neutral detergent using the washing net, the changes of bending, shearing, compression and surface properties were hardly discernible. It makes possible for Lyocell fabrics to be washed in water system by using the neutral detergent and the washing net under a mild agitation.
A pulsator type model of washing system in which a disk-like stirring bar was rotated by a magnetic stirrer in a beaker of 74 mm inside diameter and containing 250 mL of washing liquid was suggested assuming the use for consumer tests. Removal efficiency was determined by the reflectance of artificial soiled cloths (prepared by The Laundry Research Association, 5×5 cm in size) . The effects of the number of test cloths, the rotational speed of a magnetic stirrer, the washing time and the detergent concentration on the removal efficiency were examined and the standard test condition was determined. Moreover, comparative washing tests for 11 kinds of commercial detergents were conducted. The results show that the standard test condition should be as follows rotational speed 450 rpm; wash load 3 soiled cloths + 2 balance cloths; and washing time 10 min. Washing tests were repeated 11 times respectively for 11 kinds of the commercial detergents, and the following order of detergency was obtained: alkalescent synthetic detergents (powder type) = fatty acid soaps > neutral synthetic detergents (liquid type) . These results can be considered reasonable, therefore the washing test suggested in this paper is estimated to be applicable for consumer tests under limited conditions.