Some Chemical Relaxers

Lanthionization, or hair relaxing, is a chemical process whereby excessively curly hair is permanently straightened. The first relaxers were developed around 1940. They were crude concoctions of sodium hydroxide (lye) or potassium hydroxide mixed into potato starch, and were highly irritating to the scalp. However, chemical relaxers did offer a more permanent way to straighten the hair, addressing the problem of "reversion" associated with hair pressing.

Relaxer formulation: The formulation and manufacturing of relaxers tend to be quite complicated because the marketplace has come to demand that relaxer formulas meet these minimum criteria:

>Must effectively straighten a range of excessively curly hair textures-fine, medium, coarse

>Must have adequate oils and petrolatum to protect against scalp irritation

>Must be stable at 45 degrees C

>Must be a smooth, "fluffy" cream for ease of application

>Must not become pasty when applied, otherwise application and smoothing would be hindered.

>Must be very easy to rinse from hair using tepid water

>Must not damage or dehydrate hair beyond acceptable