Relaxers are chemicals that are used to straighten hair in order to remove its natural curl pattern. Some would argue that relaxed hair is easier to manage and to detangle. Disadvantages of relaxed hair include:
- You have to keep on retouching the new growth at chosen intervals to maintain the straight texture. This might be cumbersome for some people.
- Causes more damage to the hair because relaxers work by altering the structure of the peptide chain bonds in the hair. (These bonds are called disulfide bonds). As a result of this protein breakdown, relaxed hair needs more attention and must regularly be treated with protein.
The strength of a relaxer is dependent on the pH. The higher the pH, the more potent it is. Relaxers are alkaline in nature (having a pH greater than 7) and work by opening the cuticle of the hair, penetrating to the cortex and acting on the bonds within the cortex proteins. To get our hair straight, three factors are involved:
• Breaking down of the Disulfide bonds between the amino acids in the Hair’s Keratin protein. New bonds are formed which make it possible for the hair to be straightened permanently.
• The heavy, creamy nature of the relaxer being used. Relaxers are usually very thick and heavy and this helps to weigh down the hair being processed to keep it smooth and straight.
• The smoothing of the hair during the relaxing process is very important to get it straight. If very straight hair is desired, some people even use a comb. This is discouraged because of the fragile nature of the line differentiating the new growth and the previously relaxed hair. When you comb through the hair during relaxing, the hair can break off at this point.
There are 2 main classes of relaxers:
- Lye relaxers and
- No-Lye relaxers.
Other chemicals used to ‘soften’ Black hair curl pattern are Ammonium Thioglycolate (for making permanent waves e.g Wave Nouveau System) and Ammonium bisulfite (normally used in Texturizers). They will not be discussed further.
No-lye relaxers are sometimes marketed as being milder than lye relaxers but you must know that all relaxers are potentially dangerous, whether they are lye or no-lye because they contain chemicals with very high pH. You must therefore apply caution when you using them. In addition, it is important to know that kids relaxers are made from hydroxides and are equally as potentially damaging as ‘grownup’ relaxers. The only difference is that some of them have slightly lower pH than relaxers meant for adults.
Lye relaxers usually contain Sodium Hydroxide while No-Lye relaxers contain other types of hydroxides like Potassium Hydroxide, Lithium Hydroxide, Guanidine Hydroxide and Calcium Hydroxide. To easily differentiate them, Lye relaxers never have to be mixed while Guanidine/calcium hydroxides usually come in boxed kits that need to be mixed.
Due to their unstable nature, Guanidine Hydroxide relaxers don’t usually occur as Guanidine hydroxide. They are usually packaged as a relaxer base containing Calcium hydroxide and a separate activator containing Guanidine carbonate. When these 2 are mixed, Guanidine Hydroxide and Calcium hydroxide are the end-products of the chemical reaction. This is why any unused relaxer must be discarded after using this sort of relaxer: it will lose its potency after a short while.
Relaxers made from guanidine/calcium hydroxide leave calcium deposits which can give the hair a dull appearance and can only be removed by chelating agents. Calcium deposits also make it difficult for moisture to penetrate the hair, leading to hair dryness and eventual breakage. To prevent calcium deposition, you might choose to use Lithium relaxers. They however do not work well on all type of hair textures: they can make fine and medium hair very straight but only (in most cases) takes the curl out of coarse hair.
Potassium Hydroxide relaxers are extremely rare while Guanidine/Calcium Hydroxide Relaxers are the most widely available No-Lye relaxers.