Calculation of Finishing Effects on Cotton on the Basis of a Padding, Weave, and Cross-Linking Function1

Abstract

Up to now, there has been a lack of a physical-chemical function which would establish a link between the formulation of a procedure for a conventional wash-and-wear finish and the properties of the finished fabric after it has been given a household laundering. It appeared reasonably possible to work out a general function, provided excessive ac curacy was not called for. This function was arrived at by coordinating both precisely defined and approximate expressions. Details are given. The amount of cross-linking agent taken up can be calculated from the given formula tion and padding data by means of the "impregnation function." The diffusion proc esses which occur during contact with the liquor and which can be ascertained theo retically only with great difficulty can be represented by an experimentally determinable integrated factor, the "exchange coefficient." The attainable degree of finish for cotton, i.e., the crease recovery angle,' can be determined by means of the "cross-linking function," taking into account the yield of the condensation reaction and the loss in strength. The experimental basis and the range of validity of this function and its dependence on the nature of the fabric ("weave function") are dealt with in detail. Finally, the self-smoothing effect (Monsanto rating) can be given in relation to house hold laundering methods (from drip to tumble drying) by employing empirical conver sion curves. The functions are, at present, being applied to selected practical cases by means of an analog computer in order to test the utilizability of this new system of functions for re search and development purposes.