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

The first cold wave perm utilized thioglycolic acid or one of its derivatives as the active ingredient. This compound is integral to the cold wave process because it effectively breaks and reforms the disulfide bonds in the hair's keratin structure, allowing for the creation of curls and waves without the use of heat. This innovation made hair curling more accessible and less damaging compared to traditional hot perms, which often required higher temperatures to achieve the same results.

The use of thioglycolic acid or its derivatives also indicates an advancement in chemical formulation that provided stylists with more control over the perming process. The result was a more versatile method for setting hairstyles that could accommodate various types of hair textures and conditions, enhancing the overall appeal of cold wave perms in the hairstyling industry.