Launderometer based test method for determining shrinkage of wool

Abstract

A test method based on use of launderometer has been proposed for determining shrinkage of small wool samples in the lab. Effect of laundering parameters such as liquor ratio, detergent concentration, pH, temperature and time of treatment on shrinkage of wool was studied. Parameters that best simulate the extent of shrinkage obtained by the ISO 6330 test method were identified. The proposed method is conducted on 12 × 12 cm2 samples which are subjected to one wash for relaxation shrinkage – 1 g/l detergent, pH 6, 40 °C, 60 min, followed by three washes for felting shrinkage – 0.3 g/l detergent, pH 6, 40 °C, 60 min at liquor ratio of 1:20. Treated samples showed ~47% shrinkage, comparable to that obtained by the ISO method. Results obtained by the optimised process are consistent and reproducible when validated on a range of high shrinking wool fabrics. It can be concluded that launderometer-based test method can be used to test small wool samples for shrinkage with consistent and reproducible results.