According to Latoya Jones, a silk press is similar to the "press and curl" style, which was traditionally achieved using a hot comb. The Freeman Institute notes that Annie Malone was the first to patent the hot comb in the early 1900s. Sarah Breedlove, better known as Madame C.J. Walker went on to popularize the tool, also during the early 20th century . A silk press, however, is achieved with a flat iron, which originates from Ancient Egypt where hot plates were used to straighten hair. Over time, starting in the 19th century, the tong style straightening iron, which we still use today became popular.
A silk press involves washing the hair, then using a blow dryer or other stretching method to lengthen the curls to an almost completely straight state. Once the hair has been properly stretched, the hair is flat-ironed and styled so that it appears straight and bouncy without the use of relaxers, keratin or other chemicals.
Typically, in a silk press, the hair is flat ironed using the chase method where a comb is placed under the flat iron and "chased" by the flat iron to ensure that the hair is straightened as much as possible with as few passes of the flat iron as possible.
Using heat, however, is not advisable on every type of hair. Hair that is already weak or thin or has been treated with chemicals or dyes could incur more damage as a result of flat-iron use, notes Hair Finder.