What chemical is often used in hair straightening products?

In hair straightening products, ammonium thioglycolate is commonly used due to its ability to break down the disulfide bonds in the hair's keratin structure. This process alters the hair's natural curl and wave pattern, allowing it to be reshaped into a straighter form. Ammonium thioglycolate is particularly favored because it is effective and can provide a semi-permanent straightening effect when used correctly.

This chemical works by reducing the hair’s pH, making it more alkaline which helps in the alteration of the hair's structure. After the application and processing, neutralizers are often used to reform the disulfide bonds in the altered arrangement, securing the straightened style.

The other chemical options listed do not fulfill the same role in hair straightening. Ethylene glycol is primarily an industrial chemical and is not used in hair treatment applications. Formaldehyde can be found in some straightening treatments, but it is often criticized for its safety concerns and is not the primary or preferred agent in many modern formulations. Sodium chloride, or table salt, is typically used in various cosmetic formulations for different purposes but does not serve the purpose of altering hair texture like ammonium thioglycolate does. This makes ammonium thi