So what do you think?Function
Although both relaxers and rebonding formulas both have the same ultimate goal of straightening, they accomplish it in different ways. Relaxers break hair's disulfide bonds, according to Hairfinder.com, to loosen or "relax" the curl. Rebonding formulas do the same, but claim to provide the added benefit of improved shine and texture along with the new shape, according to CBS News.
Features
Relaxers often contain sodium hydroxide (lye) or ammonium thioglycolate as the active ingredients that break up the hair's bonds. Keratin treatments usually contain formaldahyde or its deratives in order to break the chemical bonds in the hair.
Effects
Lye-based relaxers "soften" the hair fibers and cause them to swell. It then penetrates into the cortex of the hair to break the bonds, according to Hair Boutique. Formaldahyde is the chemical straightening in rebonding formulas, not keratin, according to a CBS News article.
Time Frame
Keratin rebonding is a process that can take several hours depending on the length and texture of hair. It involves thermal heat, so blow drying and flat ironing are necessary for rebonding the hair into it straight shape. Relaxers take less time and don't require thermal heat tools to accomplish the straightening effect.
Misconceptions
Keratin straightening manufacturers claim that the keratin helps repair hair, but it actually just works as a veneer, covering the damage temporarily, until its effects begin to wash out over a period of weeks, according to Richard Hoffman of the Newton General Science Archive.
Considerations
Keratin rebonding treatments are safe to use on color-treated or highlighted hair. Typically chemical processes such as relaxing, bleaching and perming can not be done on these hair types because of the increased damage it will cause. Keratin treatments repair damage caused by processing hair, according to Liquid Keratin, a retailer. [source]
Tough.