Abstract

Easy-care finishes, which effectively seal the surface of upper leather, have been extensively used on leather for footwear without reference to the effect these finishes have on the properties of leather. In particular, the comfort properties have been disregarded. Since leather both absorbs and transmits water vapour, and since it is this combination of properties which cannot be matched by synthetic upper materials, these properties should be preserved in leather if at all possible. Moreover, there is no evidence to indicate which of these properties is the more important with regard to comfort. To resolve some of these queries, matched sides were made by two tanneries, one side of each being finished in the normal manner and the other with an easy-care finish. In each case, the normal finish consisted of pigmented resin with a nitrocellulose emulsion top, and the easy-care finish was a polyurethane based lacquer. Comprehensive tests were performed on the leathers, and in addition, the leathers were made up into shoes to determine rates of perspiration accumulation and wearer preference. Scuff resistance of the normal and easy-care leathers was good, but the adhesion of the easy-care finishes was infinitely superior to the resin-based finishes. Other finish properties of each type of leather were good to excellent, but marked differences were noted in water vapour permeability which, for the easy-care leathers, was only about one-tenth of the same leathers finished in the normal way. In the wear trial of the shoes, perspiration accumulation in the easy-care leather was consistently greater than in the leathers with the normal finish, regardless of the season of the year. It was noted that as micro-cracks developed in the finish, the easy-care leathers tended more nearly to resemble the conventional leathers, but there was no wearer preference, so it is probable that water vapour absorption is more important for comfort than is water vapour permeability.