Formaldehyde release from durable press shirting fabrics

The objectives of this work were to determine the level of formaldehyde release from durable press consumer products, and to compare existing test methods for evaluation of formaldehyde release and content. Men's durable press dress shirts were purchased and analyzed for formaldehyde content and release, initially and after selected laundering intervals. Three different shirting fabrics were tested; 100% cotton, 60% cotton/40% polyester, and 65% polyester/ 35% cotton.

The shirting fabrics were analyzed for total formaldehyde, free formaldehyde, and formaldehyde in methylol groups. No free or methylol formaldehyde was detected by the analytical methods employed. Total formaldehyde ranged from 4,000 to 13,000 ppm. Very little of the total formaldehyde was released in tests designed to evolve hydrolyzable formaldehyde from durable press fabrics. The two standard tests for formaldehyde evaluation, the Japanese test and the AATCC test, were performed to assess the effect of laundering on formaldehyde release. The greatest amount of formaldehyde was released from unwashed fabrics; thereafter, the fabrics quickly reached a limiting value for formaldehyde release, which was unaffected by further washing.

The two test methods for formaldehyde evolution as well as two different colorimetric procedures for formaldehyde determination, were compared. The two test methods differed significantly only at low levels of formaldehyde release. There were also significant differences between the two procedures for formaldehyde determination (acetylacetone and chromotropic acid). The latter method, CIA, proved to be more precise, perhaps because absorbance values for this reagent were in the range of minimum error.

Further comparison between the Japanese and AATCC tests was made by determining activation energies for the evolution of formaldehyde from the 100% cotton shirting fabrics. These activation energies were 21.0 kcal and 15.8 kcal respectively.