Japanese hair straightening (also referred to as Thermal Reconditioning, Japanese Perm and Straight Perm) begins with a consultation. Some hair types are better suited to the process than others, and a good salon will screen clients before beginning the process. The ideal hair type for Japanese hair straightening is coarse and curly, and one that has had few to no chemical treatments. This means no coloring and no prior perms or relaxers. Once it has been established that the hair is suitable for thermal reconditioning, the process can begin.
The individual steps involved in Japanese hair straightening vary depending on hair type, and the whole process can take anywhere from three to six hours to complete. The only constants are that clients will undergo two separate chemical treatments and will have their hair flat-ironed at least once. The time involved in each individual step varies depending on thickness and length of hair, and other factors (such as past chemical treatment and damage) that the stylist takes into consideration.
The process begins with a shampoo and a special protein conditioner. The latter is applied to preemptively guard against the chemicals to follow. After both of these are rinsed out, the first chemical treatment is applied to the hair. This chemical (thioglycolate) is known as the "retexturizer," and effectively breaks down the proteins in the hair, allowing hair to be restructured. It can take up to forty minutes under a hairdryer for the treatment to fully process. At this point the hair is physically straightened with a high-heat flat iron in 1/8-inch sections. Once the hair is straightened, a chemical neutralizer is added to maintain the new shape. At this point the hair is pulled tightly straight and allowed to dry once more. One more shampooing and straightening with the flat iron, and the process is completed.
After the process has been completed, hair must remain completely dry for at least 48 hours. Even a light misting of water can undo all the work that has been done, so umbrellas are recommended for this time period. Clients are also advised not to put their hair in a ponytail or to crimp or clip it in any way during these 48 hours. It is important to protect hair from damaging UV rays by using hair products with SPF. Stylists also suggest using special shampoos, conditioners and leave-in treatments to maintain the style.