Hair coloring

A hairdresser colors a client's hair.

Hair coloring is used:

• to return gray hair to its previous color;
• to change hair color to a shade regarded as more fashionable or desirable;
• to return hair to its original color after chemicals (e.g. tints, relaxers, sun bleaching) have discolored it.

History

In the 1661 book Eighteen books of the secrets of art & nature, various methods of coloring hair black, green, red, yellow, and white are explained.

Types of hair color

Hair coloring products are typically categorized based on how long the color persists in the hair, and how much lifting occurs. The four most common classifications are 'temporary', 'semi-permanent', 'demi-permanent' (sometimes called 'deposit only') and "permanent".

Temporary hair color

A girl with purple colored hair.

Temporary hair color is available as rinses, shampoos, gels, sprays, and foams among others. This type of hair color is typically brighter and more vibrant than semi-permanent and permanent hair color. Temporary color is most often used to color hair for special occasions and is often used in unusual shades for events, parties and Halloween.

The pigment molecules in temporary hair color are large and cannot penetrate the cuticle layer. Instead, the color particles remain adsorbed (closely adherent) to the hair shaft and are easily removed with a single shampooing.

However, even temporary hair color can persist if the user's hair is excessively dry or damaged, allowing for migration of the pigments to the interior of the hair shaft.

Semi-permanent hair color

Semi-permanent hair dye has smaller molecules than temporary dyes, and is therefore able to partially penetrate the hair shaft. For this reason, the color will survive repeated washing, typically 4-5 shampoos. Semi-permanents contain no, or very low levels of developer, peroxide or ammonia, and are therefore safer for damaged or fragile hair. However, semi-permanents may still contain the toxic compound P-Phenylenediamine or other such ingredients.

The final color of each strand of hair will depend on its original color and porosity, so there will be subtle variations in shade across the whole head. This gives a more natural result than the solid, allover color of a permanent dye. However, it also means that gray or white hairs will not dye to the same shade as the rest of the hair. If there are only a few gray/white hairs, the effect will usually be enough for them to blend in, but as the gray spreads, there will come a point where it will not be disguised as well..

In this case, the move to permanent color can sometimes be delayed by using the semi-permanent as a base and adding highlights.

Semi-permanent color cannot lighten the hair.

Demi-Permanent hair color

Demi-permanent hair color is, in fact, permanent hair dye mixed with low volume (usually a 7 volume) developer that blows off the ammonia from the permanent tube so that only color molecules penetrate the hair shaft.

Demi-permanents are much more effective at covering gray hair than semi-permanents, but less so than permanents.

Demi-permanents have several advantages over permanent color. Because there is no lifting of natural hair color, the final color is less solid than a permanent and therefore more natural looking (although that also means they may be less effective on dark hair); they are gentler on the hair and therefore safer, especially for damaged hair; and they wash out over time (typically 20 to 28 shampoos), so root regrowth is less noticeable and if a change of color is desired, it is easier to achieve.

However, demi-permanent hair colors must be used with caution because they are, in essence, permanent color and the darker shades in particular may persist longer than indicated on the packet.

Permanent color

All "permanent" haircolor products and lighteners contain a developer, or oxidizing agent, and an alkalizing agent ammonia.

When the tint containing the alkalizing ingredient is combined with the developer (usually hydrogen peroxide), the peroxide becomes alkaline and diffuses through the hair fiber, entering the cortex, where the melanin is located. Lightening occurs when the peroxide breaks up the melanin and replaces it with new color.

The ammonia opens the cuticle of the hair to allow the color pigments to penetrate deep into the hair shaft.

Permanent color is truly permanent and will not wash out, although it may fade. New hair regrowth will obviously be in the hair's natural color, meaning that regular monthly or six-weekly coloring will be essential for as long as the hair color is maintained.

Permanent haircolor is the only way to dye dark hair into a lighter shade, and it must be done in two parts: First, the hair is bleached, then color is applied.

The only way to get rid of permanent color is to undergo a stripping process (which is not possible with all colors and can damage the hair) or color it back to its natural color (which can be difficult if the color change has been extreme).

Hair lighteners and bleaches

"Hair lightening," referred to as "bleaching" or "decolorizing," is a chemical process involving the diffusion of the natural color pigment or artificial color from the hair plus the raising of the cuticle making the hair more porous.

Application techniques

Hair color was traditionally applied to the hair as one overall color. The modern trend is to use several colors to produce streaks or gradations, either on top of the natural color or on top of a single base color. These are referred to as:

• Highlighting, where sections of hair are treated with lighteners, usually to create blond streaks.
• Lowlighting, where sections of hair are treated with darker hair color.

These can be applied by the following methods:

• Foils, where pieces of foil or plastic film are used to separate off the hair to be colored; especially when applying more than one color.
• Cap, when a plastic cap is placed tight on the head and strands are pulled through with a hook.
• Balayage, where hair color is painted directly onto sections of the hair with no foils used to keep the color contained.

All application techniques can be used with any type of color. For highlights, the hair will usually have to be bleached before coloring.

Exotic hair colorants

Hair and beard colored blue.

A minority of hair coloring products are designed to create hair colors not typically found in nature. These are available in almost any color imaginable, including green or fuchsia.

These dyes are typically sold in punk-themed stores (such as comic book and music stores), with brand names like "Beyond The Zone", "Splat", "Clairol Jazzing", "Manic Panic", "Special Effects", "Punky Colour". A permanent alternative in some colors (such as bold infa-red reds and dark, inky purples and blues) is available in the U.S. under "Paul Mitchel: Inkworks" and "Chi: InfaReds". Some exotic color shades are blacklight reactive, to show up under nightclub lighting.

The chemical formulae of exotic colored dyes typically contain only tint, and have no developer. This means that they will only create the bright color of the packet if they are applied to light blond hair. People with darker hair (medium brown to black) will need to use a bleaching kit prior to tint application. Some people with fair hair may benefit from prior bleaching as well. Gold, yellow and orange undertones in hair that hasn't been lightened enough can adversely affect results, especially with pinks, blues, and greens.

Adverse effects of hair coloring

Hair coloring involves the use of chemicals capable of removing, replacing and/or covering up pigments naturally found inside the hair shaft. Use of these chemicals can result in a range of adverse effects, including temporary skin irritation and allergy, hair breakage, skin discoloration and unexpected hair color results.

Additionally, there is ongoing debate regarding more serious health consequences of hair color usage, including lead poisoning.

Skin irritation and allergy

In certain individuals, the use of hair coloring can result in allergic reaction and/or skin irritation.

Symptoms of these reactions can include redness, sores, itching, burning sensation and discomfort. If any of these symptoms occur, alert your hair colorist immediately so that they can remove the color. Symptoms will not always be present right at the application and processing of the tint but can also arise after hours or even a day.

To help prevent or limit allergic reactions, the majority of hair color products recommend that the client conduct a patch test before using the product. This involves mixing a small quantity of tint preparation and applying it directly to the skin for a period of 24 hours. If irritation develops, manufacturers recommend that the client not use the product. A skin patch test is advised before the use of every coloring process, since allergies can develop even after years of use with no reaction.

Adverse reactions can result from both at-home and salon hair coloring products, as similar chemicals are used in both settings.

In some cases, allergic reactions are caused by the aniline derivative and/or p-Phenylenediamine (PPD) found in permanent hair color.

Hair breakage

Hair that has been damaged by excessive exposure to chemicals is considered 'over-processed'. This results in dry, rough and fragile hair. In extreme cases, the hair can be so damaged that it breaks off entirely. This is especially true for Afro-textured hair, especially if used in combination with relaxers. Treatments are available but the only real solution is to stop the use of chemicals until the hair recovers.

It is advised that colored hair be deep conditioned regularly, and washed and conditioned with gentle products specifically designed for color-treated hair. This will help keep the hair intact, as well as ensuring that the color doesn't fade as quickly.

Skin discoloration

Skin and fingernails are made of the same type of keratinized protein as hair. That means that drips, slips and extra hair tint around the hairline can result in patches of discolored skin. This is more common with darker hair colors and persons with dry absorbent skin.

This discoloration will disappear as the skin naturally renews itself and the top layer of skin is removed (typically takes a few days or at most a week). A good way to prevent dye discoloration is to put a thin layer of Vaseline or any oil-based preparation around the hairline. It is recommended that latex gloves be worn to protect the hands.

Unpredictable color results

Several factors influence the final color of the hair following the coloring process.

• For semi-permanent and demi-permanent color, the final color is always a blend of the natural color of the strand and the dye color.

• Bleached blond hair will not absorb certain colors (for instance, dying blond hair brunette can result in bright red or green hair).

• Previous use of henna and "color restorers" can react unpredictably with hair dyes.

• Previous use of some volumizing shampoos, which deposit a layer of plastic on the hair can block the action of the dye.

• Presence of minerals, salts, chlorine or other environmental contaminants usually from residential water supplies or sea water

• Certain prescription drugs can alter hair chemistry

• Dying dark hair blond requires knowledge of color theory. Once the hair is bleached, it will have a yellow or coppery shade. A violet-based color must be used to cancel out yellow tones, and a blue-based shade will cancel out coppery orange.

Professional hair colorists have a number of products which can correct or reduce the impact of unintended hair coloring outcomes.

Health concerns

There is ongoing debate regarding more serious health consequences that may result from use of hair coloring.

Recent publications regarding the dangers of hair tints include:

• An FDA study that found lead acetate (the active ingredient in gradual darkening products such as Grecian formula) to be potentially toxic.
• Articles that link the development of some forms of cancer (including leukemia, non-Hodgkin's lymphoma, bladder cancer, blood cancer, and multiple myeloma) with use of hair color. More specifically, prolonged use of permanent dark hair dyes can actually double a person's risk of getting various types of blood cancer.

• Recently a known human carcinogen, 4-ABP, was found in some hair dyes that you can get off the shelf.

Alternatives to industrial tints

Ancient civilizations dyed their hair using plants. Some of the most well known are henna, indigo, Cassia obovata, senna, turmeric and amla. Others include katam, black walnut hulls, and leeks.

Presently, there are companies that do sell alternate-based dyes for people that are sensitive to PPD, a chemical found in most hair colors.

There are also said to be safer products that avoid the side-effects of most industrial tints. The safer alternatives generally contain fewer potentially toxic compounds or are plant based, and do also have temporary, semi-permanent and permanent options with the same persistence as the industrial versions - however in practice, these products often do not last as long as industrial tints. Users should be cautioned that allergic reactions are possible even from "natural" vegetable dyes.

Henna is a plant used for ayurvedic hair coloring. The red dye is commonly used as a deposit-only hair color whose active component, lawsone, binds to keratin and is therefore semi-permanent (i.e., it will wash out with time, generally a couple of months) to permanent, depending on a person's hair type. Most will achieve a permanent color after the second dye. While "natural" henna is generally a deep red-color, variations exist. These variations, however, usually contain ingredients from other plants and even synthetic dyes.

Using a plant-based color such as henna, can cause problems later when trying to do a perm or permanent hair color. Pure imported body art quality henna is claimed not to cause such problems, but most store-bought henna is mixed with additives which can lead to unpredictable results. Although it may not be visible on darker hair, the staining from henna will remain for several months and this may only be realized when dying is attempted and an unpleasant, permanent orange color results.

A new patented (USP7,55,014) technology combines mineral dietary supplements, such as iron, with very pure vegetable dyes to provide a complete line of permanent hair colors with the intensity of PPD-based colors without the problems of henna. http://www.treehugger.com/files/2008/11/natural-hair-dye-from-act-naturals.php.

See also

• Human physical appearance
• Hairstyle
• Hair highlighting
• Punk fashion
• Chapatsu

External links

• How Stuff Works "How Hair Coloring Works"
• How To Go Brunette - marie claire magazine Australia
• How To Go Blonde - marie claire magazine Australia
• Hair Colour Decoder - marie claire magazine Australia
• Hair Colour How To - marie claire magazine Australia
• How to Go From Black Hair to Bright Blonde - wikiHow