Scavengers and pH Control in Aftertreatments for Reducing Formaldehyde Release from Durable Press Cottons1

Abstract

Recent studies from this Center have demonstrated the influence of the pH of washing and of application of buffered solutions on the amount of formaldehyde released from finished fabrics in the standard AATCC sealed jar test. This work has been extended to include investigation of the effect of aftertreatments, and the in terrelated influence of pH, on formaldehyde release from durable press cottons. In cluded in the study were application of aftertreatments from solutions of salts, acids, and bases that produce various pH levels; formaldehyde scavenger agents; and scavenger agents in conjunction with pH control. Also, aftertreatments with ammonium hy droxide and ammonium salts were explored for condensing ammonia with free form aldehyde in the finish to give hexamethylenetetramine and thus reduce formaldehyde release. Fabrics were investigated that had been finished with dimethylol dihydroxyeth yleneurea, dimethylol ethyleneurea, and dimethylol isopropyl carbamate. Effectiveness of aftertreatments and scavenger applications for controlling formaldehyde release varied as a function of pH and the chemical nature of the finish. Depending on the particular finish, aftertreatments yielded formaldehyde release values ranging from considerably below that of the unwashed, finished fabric to several times that value.