What was the active ingredient used in the first cold wave?

What was the active ingredient used in the first cold wave?

• A. Thioglycolate acid
• B. Ammonium thioglycolate
• C. Sodium hydroxide
• D. Guanidine carbonate

Answer: (A)

The hair’s shape in a curl or wave comes from disulfide bonds linking keratin proteins; a reducing agent is the component that breaks those bonds so the hair can be reshaped. In the first cold wave, the active ingredient was thioglycolic acid (the thioglycolate acid). This compound donates hydrogen to the disulfide bonds, converting them into broken sulfhydryl (-SH) groups and loosening the hair’s structure. Wrapped around rods, the hair then takes on a new shape, and the neutralizer re-oxidizes the thiol groups to reform disulfide bonds in that new configuration, locking the wave in place. Historically, this acid form did the job, and later formulations favored the salt form, ammonium thioglycolate, for handling and stability. The other substances listed aren’t the reducing agent that enables the initial bond breakage in a cold wave, though ammonium thioglycolate is widely used in many modern perms.

The hair’s shape in a curl or wave comes from disulfide bonds linking keratin proteins; a reducing agent is the component that breaks those bonds so the hair can be reshaped. In the first cold wave, the active ingredient was thioglycolic acid (the thioglycolate acid). This compound donates hydrogen to the disulfide bonds, converting them into broken sulfhydryl (-SH) groups and loosening the hair’s structure. Wrapped around rods, the hair then takes on a new shape, and the neutralizer re-oxidizes the thiol groups to reform disulfide bonds in that new configuration, locking the wave in place. Historically, this acid form did the job, and later formulations favored the salt form, ammonium thioglycolate, for handling and stability. The other substances listed aren’t the reducing agent that enables the initial bond breakage in a cold wave, though ammonium thioglycolate is widely used in many modern perms.