Hair coloring
Encyclopedia
Hair coloring is the practice of changing the color of hair
. Common reasons are to cover gray hair, to change to a color regarded as more fashionable or desirable, and to restore the original hair color after it has been discolored by hairdressing processes or sun bleaching. In the 1661 book Eighteen Books of the Secrets of Art & Nature, various methods of coloring hair black, gold, green, red, yellow, and white are explained.
(currently), a coupling agent, and an oxidant. The process is typically performed under basic conditions.
The mechanism of oxidation dyes involves three steps:
1) Oxidation of 1,4-diaminobenzene derivative to the quinone state.
2) Reaction of this diimine with a coupler (more detail below).
3) Oxidation of the resulting compound to give the final dye.
The preparation (dye precursors) is in the leuco (colorless) form. Oxidizing agents are usually hydrogen peroxide
, and the alkaline environment is usually provided by ammonia. The combination of hydrogen peroxide and the primary intermediate causes the natural hair to be lightened, which provides a blank canvas for the dye. Ammonia opens the hair shaft so that the dye can actually bond with the hair, and ammonia speeds up the reaction of the dye with the hair.
Various combinations of primary intermediates and couplers provide a spectrum of shades of hair colors. The primary intermediates are aromatic para compounds, such as 1,4-diaminobenzene or 4-aminophenol. The couplers are meta-substituted derivatives of aniline
. They come in three major classes based on the color that they produce when they react with the primary intermediate.
The first step shows the oxidation of p-phenylenediamine to the quinonediimine (C6H4(NH)2):
This species exists in equilibrium with the monoprotonated form (C6H4(NH)(NH2)+) (not shown). The second step involves the attack of this quinonediimine on the coupler. In organic chemistry
, this reaction is called electrophilic aromatic substitution
:
In the third and final step, the product from the quinonediimine-coupler reaction oxidizes to the final hair dye.
The resulting hair dye is also much larger than the precursor molecules, which causes the dye to bond to the hair.
ing is a chemical process for removal of some or all natural or synthetic color from hair
. Hydrogen peroxide
and ammonium hydroxide
are common bleachants. Any color treatment to change to a lighter color requires bleaching. Subsequent to bleaching, a light colored permanant or semi permanent dye or toner may be applied.
Bleaching has the side effect of raising of the cuticle, making the hair more porous.
or other such ingredients. The U.S. Environmental Protection Agency reported that in rats and mice chronically exposed to PPD in their diet, it simply depressed body weights, and no other clinical signs of toxicity were observed in several studies.
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, all over 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 grey/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-permanents are much more effective at covering gray hair than semi-permanents, but less so than permanents.
Demi-permanents have several advantages as compared with permanent color. Because there is essentially no lifting (i.e., removal) of natural hair color, the final color is less uniform/homogeneous than a permanent and therefore more natural looking; they are gentler on 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. Demi-permanent hair colors are, in essence, permanent color and the darker shades in particular may persist longer than indicated on the packet.
.
The pigment molecules in temporary hair color are large and cannot penetrate the cuticle layer. The color particles remain adsorbed (closely adherent) to the hair shaft and are easily removed with a single shampooing. Temporary hair color can persist on hair that is excessively dry or damaged in a way that allows for migration of the pigment to the interior of the hair shaft. It lasts for about a few hours to 1 day.
These can be applied by the following methods:
All application techniques can be used with any type of color. For highlights, the hair will usually have to be bleached before coloring.
These dyes are typically sold in punk
-themed stores (such as comic book
and music
stores), with brand names like "Beyond The Zone", "Splat", 'Fudge Paintbox' 'Crazy Colors' "Clairol Jazzing", "Manic Panic", "Special Effects", "Punky Colour", "Stargazer", "La Riche Directions". A permanent alternative in some colors (such as bold red and dark, inky purples and blues) are available from big haircare brands. Some alternative color shades are blacklight reactive, to show up under nightclub lighting.
The chemical formula of alternative color 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 has not been lightened enough can adversely affect results, especially with pinks, blues and greens. Although alternative colors are semi-permanent in the cases of some colors, such as blue and purple, it could take several months to fully wash the color from bleached or pre-lightened hair.
Additionally, there is ongoing debate regarding more serious health consequences of hair color usage, including lead poisoning.
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 48 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.
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 and minimize color fading.
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 or nitrile gloves be worn to protect the hands.
Professional hair colorists have a number of products to correct or deemphasize unintended hair coloring outcomes.
(Lawsonia inermis), indigo
, Cassia obovata, senna, turmeric
and amla
. Others include katam, black walnut hulls
, red ochre and leeks. The development of synthetic dyes for hair is traced to the 1860's discovery of the reactivity of PPD with air. Hair dying is now a multibillion dollar industry that involves the use of both plant-derived and synthetic dyes.
is an orange dye commonly used as a deposit-only hair color whose active component, lawsone
, binds to keratin
. It is therefore considered semi-permanent to permanent, depending on a person's hair type. Most people will achieve a permanent color from henna, especially after the second dye. With repeated use the orange color builds up into red and then auburn. While "natural" henna is generally a red color, variations exist. These variations usually contain ingredients from other plants and even synthetic dyes.
Indigo is natural dye from a plant (Indigofera tinctoria, suffructicosa, or arrecta) that can be added to henna or layered on top of it to create brown to black colors in the hair. On the color wheel, henna is orange, and indigo is blue, so the two colors work together to create brown tones. Like henna, indigo may fade after one application, but it becomes permanent on the hair with repeated use.
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 if the hair is later colored. 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 dyeing is attempted and an unpleasant, permanent orange color results.
Hair
Hair is a filamentous biomaterial, that grows from follicles found in the dermis. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class....
. Common reasons are to cover gray hair, to change to a color regarded as more fashionable or desirable, and to restore the original hair color after it has been discolored by hairdressing processes or sun bleaching. In the 1661 book Eighteen Books of the Secrets of Art & Nature, various methods of coloring hair black, gold, green, red, yellow, and white are explained.
Types of hair coloring
The four most common classifications are permanent, demi-permanent (sometimes called deposit only), semi-permanent, and temporary.Permanent hair color
The most popular way to achieve permanent hair coloring is through the use of oxidation dyes. The ingredients of these products include 1,4-diaminobenzene (historically) or 2,5-diaminotoluene2,5-Diaminotoluene
2,5-Diaminotoluene is an organic compound with the formula C6H32CH3. It is one isomer of six with this formula. 2,5-Diaminotoluene is a colorless crystalline solid that is commonly used in hair coloring.- Formation and use:...
(currently), a coupling agent, and an oxidant. The process is typically performed under basic conditions.
The mechanism of oxidation dyes involves three steps:
1) Oxidation of 1,4-diaminobenzene derivative to the quinone state.
2) Reaction of this diimine with a coupler (more detail below).
3) Oxidation of the resulting compound to give the final dye.
The preparation (dye precursors) is in the leuco (colorless) form. Oxidizing agents are usually hydrogen peroxide
Hydrogen peroxide
Hydrogen peroxide is the simplest peroxide and an oxidizer. Hydrogen peroxide is a clear liquid, slightly more viscous than water. In dilute solution, it appears colorless. With its oxidizing properties, hydrogen peroxide is often used as a bleach or cleaning agent...
, and the alkaline environment is usually provided by ammonia. The combination of hydrogen peroxide and the primary intermediate causes the natural hair to be lightened, which provides a blank canvas for the dye. Ammonia opens the hair shaft so that the dye can actually bond with the hair, and ammonia speeds up the reaction of the dye with the hair.
Various combinations of primary intermediates and couplers provide a spectrum of shades of hair colors. The primary intermediates are aromatic para compounds, such as 1,4-diaminobenzene or 4-aminophenol. The couplers are meta-substituted derivatives of aniline
Aniline
Aniline, phenylamine or aminobenzene is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the prototypical aromatic amine. Being a precursor to many industrial chemicals, its main use is in the manufacture of precursors to polyurethane...
. They come in three major classes based on the color that they produce when they react with the primary intermediate.
-
- Blue couplers include 1,3-diaminobenzene and its derivatives.
- Red couplers include phenols and naphthols, such as 3-aminophenol (CAS#591-27-5), 5-amino-2-methylphenol (CAS#2835-95-2) and 1-naphthol (CAS#90-15-3). The combination of 2,5-diaminotoluene with the coupler 3-aminophenol gives a magenta-brown dye, while the combination of 2,5-diaminotoluene with the coupler 1-naphthol gives a purple dye.
- Yellow-green couplers include resorcinol, 4-chlororesorcinol, and benzodioxoles. These compounds produce broad-band absorption when they react to form dyes, allowing for more natural-looking hair colors. The combination of 2,5-diaminotoluene with the coupler resorcinol gives a greenish brown dye.
The first step shows the oxidation of p-phenylenediamine to the quinonediimine (C6H4(NH)2):
This species exists in equilibrium with the monoprotonated form (C6H4(NH)(NH2)+) (not shown). The second step involves the attack of this quinonediimine on the coupler. In organic chemistry
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...
, this reaction is called electrophilic aromatic substitution
Electrophilic aromatic substitution
Electrophilic aromatic substitution EAS is an organic reaction in which an atom, usually hydrogen, appended to an aromatic system is replaced by an electrophile...
:
In the third and final step, the product from the quinonediimine-coupler reaction oxidizes to the final hair dye.
The resulting hair dye is also much larger than the precursor molecules, which causes the dye to bond to the hair.
Bleaching
BleachBleach
Bleach refers to a number of chemicals that remove color, whiten, or disinfect, often via oxidation. Common chemical bleaches include household chlorine bleach , lye, oxygen bleach , and bleaching powder...
ing is a chemical process for removal of some or all natural or synthetic color from hair
Hair
Hair is a filamentous biomaterial, that grows from follicles found in the dermis. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class....
. Hydrogen peroxide
Hydrogen peroxide
Hydrogen peroxide is the simplest peroxide and an oxidizer. Hydrogen peroxide is a clear liquid, slightly more viscous than water. In dilute solution, it appears colorless. With its oxidizing properties, hydrogen peroxide is often used as a bleach or cleaning agent...
and ammonium hydroxide
Ammonium hydroxide
Ammonia solution, also known as ammonium hydroxide, ammonia water, ammonical liquor, ammonia liquor, aqua ammonia, aqueous ammonia, or simply ammonia, is a solution of ammonia in water. It can be denoted by the symbols NH3...
are common bleachants. Any color treatment to change to a lighter color requires bleaching. Subsequent to bleaching, a light colored permanant or semi permanent dye or toner may be applied.
Bleaching has the side effect of raising of the cuticle, making the hair more porous.
Semi-permanent hair dye
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 or a few weeks. 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-phenylenediamineP-Phenylenediamine
p-Phenylenediamine is an organic compound with the formula C6H42. This derivative of aniline is a colorless solid, but typically samples can contain yellowish impurities arising from oxidation. It is mainly used as a component of engineering polymers and composites. It is also an ingredient in...
or other such ingredients. The U.S. Environmental Protection Agency reported that in rats and mice chronically exposed to PPD in their diet, it simply depressed body weights, and no other clinical signs of toxicity were observed in several studies.
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, all over 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 grey/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 permanent hair color that contains an alkaline agent other than ammonia (e.g., ethanolamine, sodium carbonate) and, while always employed with a developer, the concentration of hydrogen peroxide in that developer may be lower than used with a permanent hair color. Since the alkaline agents employed in demi-permanent colors are less effective in removing the natural pigment of hair than ammonia these products provide no lightening of hair's color during dying. As the result, they cannot color hair to a lighter shade than it was before dyeing and are less damaging to hair than their permanent counterpart.Demi-permanents are much more effective at covering gray hair than semi-permanents, but less so than permanents.
Demi-permanents have several advantages as compared with permanent color. Because there is essentially no lifting (i.e., removal) of natural hair color, the final color is less uniform/homogeneous than a permanent and therefore more natural looking; they are gentler on 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. Demi-permanent hair colors are, in essence, permanent color and the darker shades in particular may persist longer than indicated on the packet.
Temporary hair color
Temporary hair color is available in various forms including rinses, shampoos, gels, sprays, and foams. Temporary hair color is typically brighter and more vibrant than semi-permanent and permanent hair color. It is most often used to color hair for special occasions such as costume parties and HalloweenHalloween
Hallowe'en , also known as Halloween or All Hallows' Eve, is a yearly holiday observed around the world on October 31, the night before All Saints' Day...
.
The pigment molecules in temporary hair color are large and cannot penetrate the cuticle layer. The color particles remain adsorbed (closely adherent) to the hair shaft and are easily removed with a single shampooing. Temporary hair color can persist on hair that is excessively dry or damaged in a way that allows for migration of the pigment to the interior of the hair shaft. It lasts for about a few hours to 1 day.
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:
- Foiling, 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.
Alternative hair colorants
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 and fuchsia.These dyes are typically sold in punk
Punk subculture
The punk subculture includes a diverse array of ideologies, and forms of expression, including fashion, visual art, dance, literature, and film, which grew out of punk rock.-History:...
-themed stores (such as comic book
Comic book
A comic book or comicbook is a magazine made up of comics, narrative artwork in the form of separate panels that represent individual scenes, often accompanied by dialog as well as including...
and music
Music
Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...
stores), with brand names like "Beyond The Zone", "Splat", 'Fudge Paintbox' 'Crazy Colors' "Clairol Jazzing", "Manic Panic", "Special Effects", "Punky Colour", "Stargazer", "La Riche Directions". A permanent alternative in some colors (such as bold red and dark, inky purples and blues) are available from big haircare brands. Some alternative color shades are blacklight reactive, to show up under nightclub lighting.
The chemical formula of alternative color 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 has not been lightened enough can adversely affect results, especially with pinks, blues and greens. Although alternative colors are semi-permanent in the cases of some colors, such as blue and purple, it could take several months to fully wash the color from bleached or pre-lightened hair.
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 sometimes not be apparent immediately following the application and processing of the tint, but can also arise after hours or even a day later. To help prevent or limit allergic reactions, the majority of hair colorHair color
Hair color is the pigmentation of hair follicles due to two types of melanin: eumelanin and pheomelanin. Generally, if more melanin is present, the color of the hair is darker; if less melanin is present, the hair is lighter...
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 48 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.
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-Caribbean hair, especially if used in combination with relaxers. Treatments are available but the only real solution is to stop the use of chemicals until new hair grows and the damaged hair is cut off.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 and minimize color fading.
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 or nitrile 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 a blend of the natural color of the hair and the dye color.
- Bleached hair will often require pre-pigmentation before a color application. Dyeing bleached hair brown can result in grey or very ashy (grey sheen) hair.
- Previously color treated hair can react unpredictably with subsequent color treatments.
- Previous use of shampoos which deposit a layer of plastic on the hair can block the action of the dye.
- Presence of minerals, salts, chlorine or other contaminants in the water used in the coloring process
- Certain prescription drugs can alter hair chemistry
- Coloring dark hair to achieve a desirable shade of blond requires bleaching, followed by a secondary color treatment. Bleached hair can still have a yellow or coppery shade. A violet-based color can cancel out yellow tones, and a blue-based shade will cancel out coppery orange.
- Porosity of hair can affect the final shade. Usually porous hair 'soaks' up the color more, therefore often turning out darker than expected.
Professional hair colorists have a number of products to correct or deemphasize unintended hair coloring outcomes.
Health concerns
- A PPD lead acetateLead acetateLead acetate can refer to:* Lead acetate , Pb4* Lead acetate , Pb2...
(the active ingredient in gradual darkening products such as Grecian formulaGrecian formulaGrecian Formula is a popular men's hair coloring product in the United States. It is made by Combe Incorporated in White Plains, New York, and is also known as Grecian Formula 16. It is available as a clear liquid, cream and a foam...
) is toxic if ingested. - Articles link the development of some forms of cancerCancerCancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
(including leukemiaLeukemiaLeukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases...
, 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 double a person's risk of getting some types of blood cancer. - In 2004 a known human carcinogen, 4-aminobiphenyl4-Aminobiphenyl4-Aminobiphenyl is an amine derivative of biphenyl. It is used to manufacture azo dyes. It is a known human carcinogen and so it has been largely replaced by less toxic compounds. It is similar to benzidine....
or 4-ABP, was found in some hair dyes that one can get off the shelf. However, evidence is limited and inconsistent for the link between cancer from hair dye.
History
The dying of hair is an ancient art. In ancient times, the dyes were obtained from plants. Some of the most well known are hennaHenna
Henna is a flowering plant used since antiquity to dye skin, hair, fingernails, leather and wool. The name is also used for dye preparations derived from the plant, and for the art of temporary tattooing based on those dyes...
(Lawsonia inermis), indigo
Indigofera tinctoria
Indigofera tinctoria bears the common name True indigo. The plant was one of the original sources of indigo dye. It has been naturalized to tropical and temperate Asia, as well as parts of Africa, but its native habitat is unknown since it has been in cultivation worldwide for many centuries. Today...
, Cassia obovata, senna, turmeric
Turmeric
Turmeric is a rhizomatous herbaceous perennial plant of the ginger family, Zingiberaceae. It is native to tropical South Asia and needs temperatures between 20 °C and 30 °C and a considerable amount of annual rainfall to thrive...
and amla
Indian gooseberry
Phyllanthus emblica , the Indian gooseberry, or aamla, is a deciduous tree of the Phyllanthaceae family. It is known for its edible fruit of the same name.-Plant anatomy and harvesting:...
. Others include katam, black walnut hulls
Black Walnut
Juglans nigra, the Eastern Black walnut, is a species of flowering tree in the hickory family, Juglandaceae, that is native to eastern North America. It grows mostly in riparian zones, from southern Ontario, west to southeast South Dakota, south to Georgia, northern Florida and southwest to central...
, red ochre and leeks. The development of synthetic dyes for hair is traced to the 1860's discovery of the reactivity of PPD with air. Hair dying is now a multibillion dollar industry that involves the use of both plant-derived and synthetic dyes.
Plant-based dyes
HennaHenna
Henna is a flowering plant used since antiquity to dye skin, hair, fingernails, leather and wool. The name is also used for dye preparations derived from the plant, and for the art of temporary tattooing based on those dyes...
is an orange dye commonly used as a deposit-only hair color whose active component, lawsone
Lawsone
Lawsone , also known as hennotannic acid, is a red-orange dye present in the leaves of the henna plant as well as jewelweed . Humans have used henna extracts containing lawsone as hair and skin pigments for more than 5000 years...
, binds to keratin
Keratin
Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...
. It is therefore considered semi-permanent to permanent, depending on a person's hair type. Most people will achieve a permanent color from henna, especially after the second dye. With repeated use the orange color builds up into red and then auburn. While "natural" henna is generally a red color, variations exist. These variations usually contain ingredients from other plants and even synthetic dyes.
Indigo is natural dye from a plant (Indigofera tinctoria, suffructicosa, or arrecta) that can be added to henna or layered on top of it to create brown to black colors in the hair. On the color wheel, henna is orange, and indigo is blue, so the two colors work together to create brown tones. Like henna, indigo may fade after one application, but it becomes permanent on the hair with repeated use.
Using a plant-based color such as henna can cause problems later when trying to do a perm
Permanent wave
A permanent wave, commonly called a perm, involves the use of chemicals to break and reform the bonds of the hair. The hair is washed and wrapped on a perm rod and waving lotion is applied with a base. This solution creates a chemical reaction that softens the inner structure of the hair by...
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 if the hair is later colored. 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 dyeing is attempted and an unpleasant, permanent orange color results.
See also
- Human physical appearanceHuman physical appearanceHuman physical appearance refers to the outward phenotype or look of human beings. There are infinite variations in human phenotypes, though society reduces the variability to distinct categories...
- HairstyleHairstyleA hairstyle, hairdo, or haircut refers to the styling of hair, usually on the human head. The fashioning of hair can be considered an aspect of personal grooming, fashion, and cosmetics, although practical, cultural, and popular considerations also influence some hairstyles.-History of...
- Hair highlightingHair highlightingHair highlighting/lowlighting refers to changing a person's hair color, using lightener or haircolor to color strands of the hair in varying sizes. There are four basic types of highlights: foil highlights, hair painting, frosting, and chunking. Highlights can be done in natural or unnatural colors...
- Punk fashionPunk fashionPunk fashion is the clothing, hairstyles, cosmetics, jewelry, and body modifications of the punk subculture. Punk fashion varies widely, ranging from Vivienne Westwood designs to styles modeled on bands like The Exploited. The distinct social dress of other subcultures and art movements, including...
- ChapatsuChapatsuLiterally "brown hair", is the once-rebellious, once-trendy style of bleaching hair, found among Japanese teens.While the style itself began to show up in Tokyo streets during the early to mid-1990s, the word did not appear in Kōjien until 1998...