Chemical Hair Straightening Faqs By Karen M. Shelton

When you have naturally curly hair you basically have two options. You can accept it "as is" or you can straighten it. If you decide to straighten it you can do it chemically or you can do it with products that promise to tame the curls on a day by day basis.

If you decide to straighten your hair, both the chemical and day to day versions have positive and minus considerations. The purpose of this article is not to discuss the pros and cons of chemical vs non chemical straightening. The goal of this article is to present as much information as possible on the chemical process. This article is neither for nor against straightening. It only presents the faqs.

Karen M. Shelton
The Hair Boutique

The most common reason that people decide to have their hair straightened is to eliminate curls. Sometimes this process will be used also to soften or eliminate wavy hair. Chemical hair straightening, also known as relaxing, involves a process where the basic structure of overly curly or wavy hair is changed into a straight form.

Both relaxing and permanent waving utilize fairly strong chemicals that are applied directly to the to the hair shaft. However, their objectives are reversed. While a perm is designed to add curls or waves, a relaxing treatment is designed to remove them.

Consult A Professional

Chemical hair straightening is not a difficult procedure, but it does require a thorough technical knowledge of the relaxing process. Therefore it should always be performed by a hair care professional with a track record of success with straightening.

It is best to have the relaxing process performed by a professional so that they can perform a strand test to determine the recommended strength of the relaxer that should be used. The stylist will also need to evaluate current hair texture, porosity, elasticity and the presence or absence of any hair damage.

Fine, chemically lightened, or colored hair generally requires a very mild relaxing formula. Normal, medium-textured virgin hair can tolerate regular strength relaxers. Coarse virgin hair may require a strong or super relaxing formula. The professional will be able to determine the best type of relaxing formula based on the results of a strand test and by looking at and touching the hair to be treated.

A good professional will also keep detailed records of any chemical relaxing treatments that have been performed on the hair and can use those written records to determine the best course of treatment.

Hair Strand Test

A professional hair stylist that is well versed in chemical straightening will always do a strand test on any hair that is to be treated. This not only protects the client's hair but helps the stylist determine the best type of formula to use, whether to use a conditioner-filler on the hair before applying the chemicals and whether a base petroleum protection layer is needed or not.

A strand test can be done in a variety of ways which include:

Products Used During Chemical Hair Relaxing

The following products are generally used in chemical hair relaxing procedures:

Overly curly hair that contains damage from ongoing use of heat appliances or other chemicals may need to be conditioned before relaxer can be applied. In the case where the hair is severely damaged, it may be best not to apply a chemical relaxer until the hair has had a chance to recover.

In other cases a conditioner-filler is required before the chemical relaxer can be applied to dry hair. These fillers protect hair that may be overly porous or hair that is slightly damaged from being over-processed.

Sodium Hydroxide, Guanidine Hydroxide & Ammonium Thioglycolate

There are three basic types of hair relaxers. These are sodium hydroxide and guanidine hydroxide which may or may not require pre-shampooing, and ammonium thioglycolate, which may require a pre-shampooing.

Sodium Hydroxide

Sodium hydroxide is the strongest of the three relaxers and will provide the most dramatic results. Sodium hydroxide is a caustic type of chemical that actually softens hair fibers. The chemical also causes the hair to swell at the same time. As the sodium hydroxide solution is applied to the hair, it penetrates into the cortical layer and breaks the cross-bonds.

The cortical layer is actually the middle or inner layer of the hair shaft that provides the strength, elasticity and shape of the curly hair.

Depending on various factors and the condition of the hair to be straightened, the strength of the sodium hydroxide solution may vary anywhere from 5 to 10 percent. The pH faction may vary from 10 to 14. The higher the strength of sodium hydroxide, the higher the pH and the faster the straightening solution will take hold.

Also, the stronger the solution, the more potential damage can occur to the hair. Sodium hydroxide contains a high alkaline content and so special care should always be used when applying this chemical.

Guanidine Hydroxide

Guanidine hydroxide relaxers are referred to as the "no-lye" relaxers and they tend to be less damaging than sodium hydroxide relaxers. These products, however, still may do some damage to the hair. It can definitely de-fat the scalp.

Guanidine hydroxide relaxers usually require conditioning treatments before and after. These relaxers are a mixture of calcium hydroxide cream with guanidine carbonate "activator" solution.

Ammonium Thioglycolate

Ammonium thioglycolate (nicknamed "thio relaxer") is much less drastic in its action than the sodium hydroxide and even, in some cases, the guanidine hydroxide. It acts a little differently by softening and relaxing overly curly hair through changes to the hair's cystine linkage.

Thio works on the same formulation principles as thioglycolate permanent waves. With a pH of 9-9.5, these are also considered to be less damaging, yet still require a neutralization step. Thioglycolate relaxers are usually in cream or gel form and can be preceded by a pre-softener.

Since thio relaxers are considered much milder, the risk of hair damage is also reduced by comparison to the sodium hydroxide.

Petroleum Cream/Base Cream

A protective base of petroleum cream is usually applied to the scalp and other areas of the hair that have been previously straightened to prevent over processing, hair breakage or burning and/or irritation of the scalp and skin.

The protective base is applied freely to the entire scalp with the fingers. The hairline around the forehead, nape of the neck and over and under the ears must be completely covered. The base should actually lay on the scalp and should not be spread or rubbed into the skin or scalp.

The relaxer formula must never come in contact with sores or abrasions on the scalp of the skin and should never make contact with the eyes.

The cream that is used as a base for relaxing is lighter than regular petroleum jelly and is designed to melt at body temperatures. As the cream melts is provides a complete protective covering over the scalp and other desired areas with a oily film. This film acts as a barrier against the straightening chemicals.

Some relaxing solutions are mild enough that they do not require the protective petroleum base application. The petroleum creme may or may not be required for the thio type of softening process. However, it would be more likely required for sodium hydroxide relaxing treatments.

Whether a relaxing formula requires the petroleum cream or not, it is always best to use a protective cream around the hairline and over the delicate ear areas. It is also best to apply a base during any chemical "retouching". It is advisable not to reapply a straightening formula to hair that has been previously straightened since there is a high risk of breakage or damage.

Karen M. Shelton is the founder of HairBoutique.com which has been featured in numerous magazines including 101 Celebrity Hairstyles, Today's Dallas Woman Magazine, WE-Women's Enterprise, The National Enquirer, American Salon Magazine and Self magazine, as well as international publications.

Karen M. Shelton was featured in DFW Tech Biz as winner of the Emerging CEO - Tech Titan award. In 2001 Ms. Shelton joined 101 Celebrity Styles & Short Cuts magazine as consumer hair editor.