Wrinkle-free cotton means less time spent ironing. (Image source: Jonathan Borba/Pexels)

Ironing, which used to be a weekly and time-consuming chore, has been on a sharp decline worldwide, in large part due to wrinkle-free cotton. (The trend predates the rising popularity of athleisure.) “Wrinkle-free cotton”… it sounds great, as if it just magically avoids wrinkles, doesn’t it? But how did the world get wrinkle-free cotton? The story traces its beginnings to the 1950s and a federally funded research center in Louisiana. There, United States Department of Agriculture chemist Ruth Benerito led a team that figured out how to wrangle the cotton fibers in cloth so that they resist wrinkles after getting wet.

Benerito was one of just two women who were allowed to take physical chemistry classes at Tulane University. Those classes led to her earning her doctorate from the University of Chicago in 1948 and eventually to the creation of wrinkle resistant cotton.

The process of creating “wash and wear” fabrics is like what happens when chemical relaxers are used to make curly hair straight. Cotton is a polymer—a very long molecule that can be thought of like a chain—and its strands tend to kink up after getting wet, leading to wrinkled shirts, sheets, pillowcases, and more.

In the laboratories at the United States Department of Agriculture’s Southern Regional Research Center, Benerito discovered that washing the cotton fibers with a specific type of acid that includes one chlorine atom strengthened the connections between the polymer’s strands. That extra strength helps them resist being bent into kinks. Chemical relaxers for hair only last until new hair grows in, but the acid wash that Benerito discovered transformed cotton clothing and household linens from being wrinkle prone to being permanently wrinkle resistant. Of course that made cotton a much more attractive fabric for consumers than it would be otherwise. Not only did this federally funded discovery save millions from the tedium of standing at an ironing board for hours each week, but it also saved the American cotton industry!