Hair straighteners, sometimes known as flat irons, are hot metal plates that are pressed together to make hair appear straighter. Hair straightening is not permanent and will disappear when water is applied. Hair straighteners are similar to curling irons because they both involve the heating of metal to remove the hydrogen molecules from hair follicles. Once the hair is wet, the hydrogen molecules re-enter the hair and the hair returns to its original form. Straight hair became popular when women in the 1960s started using clothing irons to straighten their hair.


The first heat rods were created and used in 1872 by Erica Feldman, who took heated irons and applied them to the head to shape hair. But she did not create an actual device to straighten hair. Ian Gutgold was the first to experiment with hair-straightening chemicals but stopped his experimentation after burning the scalps of several women. In 1912, Lady Jennifer Bell Schofield created the first straightening iron involving two metal plates that rested between a hinge--still the straightening model we use today.


Although Jennifer Schofield created the basic model of the hair straightener, many modern improvements have been made on the invention--including the use of electricity to heat the metal plates, temperature control and the ability to straighten wet hair. Commercial hair straighteners were not readily available on the market for women to buy until the 1990s but are now available in hair care supply stores, drugstores and grocery stores all over the world.


Several patents were made on hair straighteners before the first straightener was actually invented. The most notable patent was claimed by Isaac Shero in 1809, in which the original idea of pressing two hot plates together was conceived. Although Shero did not invent the actual product, he is largely responsible for what the modern straightening iron looks like today. With the exception of some straighteners that involve straightening combs or a curling component, straighteners have not changed much in design since 1809.


Using hair straighteners can cause damage to your hair over time. If you straighten your hair more than twice a week, deep condition your hair with a hot wax treatment once a week. You may find that your hair becomes dry and brittle after using a straightener, and you may discover more split ends than you previously had. If you are experiencing a major change in your hair, discontinue using your straightener, curling iron and other styling products.


Do not use a hair straightener near water or in the bathtub. Only use a hair straightener on the lowest setting that works for you. If you use a high setting on thin hair, you may experience burning on your hair or scalp. If you burn your scalp using a hair straightener, apply a cold compress and see a doctor immediately. If you find your hair does not become straight after using the lowest setting, raise the temperature slowly until you find a setting that is right for your hair.