Glyoxal as a Non-Nitrogenous Formaldehyde-Free Durable-Press Reagent for Cotton'

Abstract

Glyoxal was found to impart a high degree of wrinkle resistance and smooth drying qualities to all-cotton printcloth. Certain aluminum salts were effective catalysts, the least fabric discoloration being produced with aluminum sulfate. Addition of ethylene glycol or glycerol to the treating solutions eliminated almost all of the discoloration and increased the durable-press appearance ratings. Evidence is presented that the catalytic activity of aluminum sulfate is not explainable on the basis of generation of sulfuric acid by partial hydrolysis of the aluminum salt, and that metal ion catalysis, as well as specific catalysis by hydrogen ions, may take place in the case of glyoxal crosslinking of cellulose. Unlike formaldehyde, glyoxal monomer, dimers, and trimers have structures favorable for chelation by polyvalent metal ions, and such complexes may play a part in the crosslinking reactions. At ordinary concentrations of glyoxal, the durable-press treatments produced very large strength losses in the fabric, but the use of high glyoxal concentrations resulted in large improvements in strength retention.