What's the story of hair straighteners
 

What's the story of hair straighteners
History
A stylist named Erica Feldman was the first to use heated metal rods to straighten and curl hair,Thomas Sabo Starfish Pendant with Lobster Clasp, but hair straightening became most popular in the 1960s, when many women used clothing irons to straighten their own hair. This process was considered dangerous because the iron could be set very high and could burn through the hair. The hair iron that is very similar to the straighteners we use today was patented by Isaac K. Shero in 1909.
Function
Curly or wavy hair contains hydrogen bonds that allow it to twist and turn where the hydrogen has bonded inside the cortex of the hair. Using a straightening iron removes the hydrogen bonds, creating smooth, straight hair when it is completely free of these bonds. The hydrogen bonds will form again once hair is exposed to water or humidity. This is why straightened hair usually holds until taking a shower or washing your hair.
Types
There are several hair straighteners on the market that use ions to straighten the hair instead of harsh heat. Whether or not these straighteners actually use ions to straighten the hair is unproven. Metal straighteners and ceramic straighteners style hair in the same fashion, except it is believed that ceramic straighteners last longer and are not as hard on the hair because it still retains heat but is more porous than metal.