. "It is more preferred to use a substrate of the formula R2 COZ wherein R2 is an alkyl or alkenyl group of 3 to 19 carbons in length; Z is -OX, -OCH2 CHOR3 CHOR4 or --NR5 R6 ; X is hydrogen, alkyl of 1 to 6 carbons, an alkali or alkaline earth metal cation or an ion exchange resin; R3 and R4 independently are hydrogen, alkyl of 1 to 6 carbons or R2 CO; and R5 and R6 independently are hydrogen or alk" . . .