Chemical formula and heat work together to strengthen the hair shaft and lead to silky, frizz-free hair
What You'll Get
- Keratin Treatment
- Japanese Straightening Treatment
Japanese Straightening: Chemistry of the Curl
Unlike a flat-iron or keratin treatment, Japanese straightening permanently removes hair’s curl. Find out how in this Groupon guide.
Curly hair is caused by genetics, of course, but it’s also caused by some basic chemistry. Ringlets, kinks, and waves arise when pairs of sulfur atoms in the amino acid cysteine link up together, forming, appropriately enough, disulfide bonds. (There’s a lot of cysteine in hair because it’s one of the major building blocks of keratin, the protein that makes up most of the hair shaft.) During this process, each of the sulfur atoms sheds an electron, and that’s what allows one of the most reliable techniques for straightening hair to work.
During Japanese hair straightening, a reducing agent—in this case a chemical known as thioglycolate—forces electrons back onto the sulfur atoms, reversing the process that created the bond. After the hair is nourished with shampoo and a protein-rich conditioner, the stylist will apply a solution of thioglycolate that’s activated by the heat of a dryer. A flat-iron then makes hair as straight as possible before a chemical neutralizer tells the thioglycolate to stop processing and keeps the hair in its new shape.
The process often takes three to four hours, and clients shouldn’t style or wash their hair for about three days afterward to avoid disrupting the treatment or losing that nice salon smell sooner than necessary. The chemical reaction is permanent, and changes the actual structure of the hair—that’s why Japanese-straightened hair won’t curl again the way keratin-smoothed or flat-ironed hair eventually does, at least until it grows out. At that point, if you want to maintain the sleek look, you can go back to the salon to touch up the roots.
The Fine Print
Promotional value expires 120 days after purchase. Amount paid never expires. Appointment required. Consultation required; non-candidates and other refund requests will be honored before service provided. Additional fees may apply depending on hair length, texture, and density. Limit 1 per person, may buy 1 additional as gift(s). Valid only for option purchased. All goods or services must be used by the same person. Merchant's standard cancellation policy applies (any fees not to exceed voucher price). Merchant is solely responsible to purchasers for the care and quality of the advertised goods and services.