Permanent press finish as a factor in growth of microorganisms

Includes bibliographical references (pages 46-47)Permanent press fabrics are popular today because of their easy care properties. However, it has not been verified whether or not this same finish might also act as an antibacterial agent. Therefore, this study investigated the hypothesis that permanent press finishes might stop or curtail bacterial growth on fabrics. Inoculations of two bacteria, E. Coli and B. mega on finished and unfinished fabric samples provided results for a comparative study. Some samples were inoculated and plated immediately; others were inoculated and kept in a humidity chamber for twenty-four hours before plating to simulate storage and climatic conditions; and a third group were inoculated, kept in a humidity chamber for twenty-four hours and then laundered in and according to suggested Launderometer standards. The samples from this last test were then either plated whole or macerated and plated. The Agar Plate Test method (AATCC test standard for detection and evaluation of antibacterial finishes) and the Streak Test method were used for another set of tests. Another segment of the study concerned naturally soiled finished and unfinished fabrics. Small samples of each fabric were sewn in regular clothing, worn\ud one day, and then plated. The permanent press samples that were inoculated and subsequently plated showed little or no growth whereas all the unfinished samples showed considerably increased growth. The permanent press samples that were inoculated and stored for twenty-four hours in a humidity chamber before plating showed no growth while the unfinished samples all exhibited bacterial growth. Of the samples that were inoculated, stored for twenty-four hours in the humidity chamber, washed, and plated whole, all finished samples had no growth but all untreated samples showed growth. Of the washed samples that were macerated, the untreated macerated fibers showed from five to six times more growth than the permanent press samples. The Agar Plate Test and Streak Test both showed that the permanent press samples inhibited bacterial growth whereas the unfinished samples showed no inhibition of growth. On all samples of naturally soiled permanent press fabrics, the majority of samples containing bacterial growth had less growth than the unfinished samples. These results would indicate that the permanent press finish can inhibit some bacterial growth and thus may act concomitantly as an antibacterial finish