A METHOD FOR DETERMINING THE DISTRIBUTION OF CATIONIC SHRINK-RESIST RESINS ON WOOL

Abstract

A method for determining the distribution of cationic shrink-resist resins on wool has been developed. The method is based on a staining technique, using an anionic fluorescent brightening agent (FBA) under specific conditions in which the FBA stains the cationic resin in preference to the wooL When the stained sample$ are observed under ultraviolet radiation by means of the optical microscope, the areas on the wool libres where resin is located fluoresce, whereas areas free from resin appear dark. The technique is simple and rapid, and enables the regularity of deposition of cationic resins on wool to be followed when the various parameters which playa role in the pretreatment of the libre and the application ofresins are changed. Regularity ofresin deposition is important in the achievement of high levels of shrink-resistance in treated fabrics.