History
Advances in producing permanent press fabrics involved a series of agents that crosslink the cellulose-based fibers that comprise most clothing. Initial agents included formaldehyde. Starting in the 1940s a series of urea-formaldehyde derivatives were introduced. Technical issues overcome included yellowing, odor, and the tendency of some agents to accelerate the degradation of fabrics by bleaches. The technology advanced especially rapidly in the early 1990s.
In older washing machines, the permanent press setting sprays moisture during the spin cycle to maintain the moisture content of the permanent press fabrics above a certain specified limit to reduce wrinkling.
Most older clothes dryers feature an automatic permanent press setting, which puts clothes through a cool-down cycle at the end of the normal heated drying cycle. Modern dryers tend to include this as a standard feature.
Read more about this topic: Permanent Press
Famous quotes containing the word history:
“Boys forget what their country means by just reading “the land of the free” in history books. Then they get to be men, they forget even more. Liberty’s too precious a thing to be buried in books.”
—Sidney Buchman (1902–1975)
“... all big changes in human history have been arrived at slowly and through many compromises.”
—Eleanor Roosevelt (1884–1962)
“No matter how vital experience might be while you lived it, no sooner was it ended and dead than it became as lifeless as the piles of dry dust in a school history book.”
—Ellen Glasgow (1874–1945)