Conditioner
Related Terms
Chemical hair straightening, conditioner, Japanese hair straightening, hair coloring, Henna hair dye, highlighting, keratin, shampoo, perm, permanents, thermal hair straightening,
Background
Hair color, texture and body vary significantly among humans and are determined primarily by genetics. Temperature, humidity, and exposure to the sun also have an affect on the texture and body of hair. Hair styling is very popular among both men and women across various cultures.
Hair is composed of strong structural protein called keratin. This is the same kind of protein that makes up the nails and the outer layer of skin.
Each strand of hair consists of three layers. The innermost layer or medulla is only present in large thick hairs. The middle layer known as the cortex provides strength and both the color and the texture of hair. The outermost layer is known as the cuticle, which is thin and colorless and serves as a protector of the cortex.
Chemical hair straightening and permanents (perms): Both relaxing and permanent waving utilize fairly strong chemicals that are applied directly to the hair shaft. While a perm is designed to add curls or waves, a relaxing treatment is designed to remove them. Hair texture and curl is determined by the arrangement of sulfide bonds in each strand. The arrangement of sulfide bonds is largely a product of genetics, although environmental factors such as humidity may also affect the hair. Chemical hair straightening and perms alter the number of sulfide bonds in a strand of hair, thus rendering a look of more or less curl.
Hair coloring: Hair colorings affect different parts of the hair. Temporary hair dyes simply coat the individual strands of hair, and wash out within a week. Semi-permanent dyes penetrate the strands of hair and bond to keratin. Permanent dyes penetrate to the core of the hair strand, and often make their way into the hair follicle on the scalp.
Hair straightening with heat (thermal hair straightening): In this treatment, dry or semi-dry hair is held up against a heat source, normally a hair iron. The treated hair will remain straight for a period of hours or days. This procedure also dries the hair, and may result in broken or split ends. This procedure usually involves no chemicals.
Henna hair dye: Henna is a mixture of natural dyes from plants, lemon juice, and water. The dye is rubbed into the hair. In this process, the dye molecule penetrates past the outside layer of the hair and bonds to the keratin molecules on the inside of the hair. Because this process occurs on the microscopic level, the result is an overall change in hair color. Many people prefer this process because the smell is not as adverse as commercially available products.
Highlighting: In this method, the entire head of hair is not treated. Instead, dye is only applied to particular parts of the hair, which is separated, usually by aluminum foil.
Japanese hair straightening: Chemical hair straightening makes fuzzy, curly, unmanageable hair appear soft and silky. This technique was originally developed in Japan for clients who wanted to smooth out their wavy, unruly hair. Japanese hair straightening uses chemicals similar to chemical hair straightening; however, this particular procedure takes extra care to apply chemicals that avoid the normal side effects of dry, brittle hair. It is a permanent treatment, which means the hair will not revert to its original texture. It will be straight until it grows out or is cut off.
Shampoo and conditioner: These products work to remove grease residue produced by hair follicles. However, nearly every shampoo and conditioner now includes a variety of other scents and chemicals.
Author information
This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Bibliography
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Chemical Hair Straightening. 30 May 2006.
Cosmetic, Toiletry, and Fragrance Association. 30 May 2006.
Hair Straightening Process. 30 May 2006.
Henna for Hair. 30 May 2006.
The Effects of Hair Straightening. 30 May 2006.