Also in this week's C&EN,
this vitally important topic (article by Prachi Patel):
Soon after the 2024 Major League Baseball (MLB) season started in March, sweat stains began to bloom along with spring flowers. In particular, sweat seemed to be soaking through the gray uniform jersey that team members wear when they play away from home, turning them visibly dark.
It shouldn’t surprise anyone, especially sports apparel companies, that athletes sweat. And synthetic sport performance fabrics, whether they’re intended for soccer, track, tennis, or lower-impact activities, are designed to provide temperature control and antibacterial properties to help keep their wearers comfortable and fresh.
In fact, 6 years’ worth of engineering went into the Nike Vapor Premier baseball uniforms, designed by Nike and manufactured by Easton, Pennsylvania–based Fanatics, according to the MLB. So what went wrong?
C&EN asked textile researchers to speculate, and they had fun doing it. “Textile structures are incredibly complex, and when you add chemical finishes, the degree of complexity multiplies,” says Juan Hinestroza, professor of fiber science and apparel design at Cornell University. So the answer to what possibly went wrong is “all of the above,” he says...
Because I'm a chemical manufacturing weirdo, this from the article makes the most sense to me.
...Whatever the underlying chemical or material gaffe, the problem most likely stems from the uniforms’ complex manufacturing chain. Every MLB jersey and pair of pants is the product of multiple fiber and yarn producers, textile mills, and chemical suppliers spread across the world. To Henry Boyter, an expert on textiles and finishes and director of the Center for Environmentally Sustainable Textile and Apparel Businesses, it’s probably a quality control issue. “There is a large amount of testing that should have been done to ensure quality and that was probably not done,” he says. “We only know for sure that human wear trials were not completed, or ignored.”
I am rather surprised that these issues didn't turn up in their testing, or they ignored these issues. Either way, it doesn't seem like this is turning out well for MLB. I suspect that the second version of these uniforms will be better, but we shall see.