30—PERMANENT-PRESS EFFECTS IN WOOL. PART XIV: THE RETENTION OF SET IN POLYMER-TREATED WOOL UNDER VARIOUS WASHING CONDITIONS

Abstract

The rate of loss of set in wool fabric during machine-washing increases with the temperature of the wash liquor. The application of a pre-formed polymer to the set wool retards loss of set, especially at lower washing temperatures. In addition, under commonly used laundering conditions, set is lost at a faster rate in machines with a vigorous washing action than in machines with a mild action. It is believed that the higher average level of strain imposed on the samples by the more vigorous washing actions leads to an increase in the rate of stress relaxation in the fibres.