Hair dye , or dyeing hair , is a practice of changing hair color. The main reason for this is cosmetics: to cover gray or white hair, to turn into a color that is considered more fashionable or desirable, or to restore the natural hair color after it has been blackened with a hairdressing or sun whitening process.
Hair coloring can be done professionally by a hairdresser or independently at home. Currently, hair coloring is very popular, with 75% of women and 18% of men living in Copenhagen have reported using hair dye according to a study by the University of Copenhagen. Coloring at home in the United States reached $ 1.9 billion in 2011 and is expected to increase to $ 2.2 billion by 2016.
Video Hair coloring
Histori
Diodorus Siculus, a Greek historian, explains in detail how the Celtic people dyed their blond hair: "Their aspect is terrible... They are very tall, with muscles rippling under clean white skin, their hair is blond, but not naturally so: they whitened it, to this day, artificially, washed it with lime and combed it from their forehead.They look like wooden devils, their hair is thick and hairy like a horse mane Some of them are clean-shaved, but others- especially those of high rank - shave their cheeks but leave whiskers that cover the whole mouth... ". This practice continued in some parts of Britain shortly after the Fall of the Western Roman Empire, particularly in Wales, where Llywelyn Ap Gruffudd was depicted in elegant form by Gruffudd ab yr Ynad Coch has blonde hair: "... Not since Camlann has anyone like crying, Gone is our mainstay, his golden hair, stained with a death blow... ".
Hair dyeing is an ancient art that involves hair care with various chemical compounds. In ancient times, dyes were obtained from plants. Some of the most famous are boyfriend ( Lawsonia inermis ), indigo, Cassia obovata, senna, turmeric and amla. Others include katam ( buxus dioica ), black walnut canary, red ocher and spring onion. In 1661 Eighteen Secrets of Arts & amp; Nature , various methods of staining black, gold, green, red, yellow, and white hair are described. The development of synthetic dyes for hair is traced to the discovery of 1860s para-phenylenediamine reactivity (PPD) with air. EugÃÆ'¨ne Schueller, founder of L'Orà © Ã… al, was known for creating the first synthetic hair dye in 1907. In 1947, the German cosmetics company Schwarzkopf launched its first home color product, "Poly Color". Hair dyeing is now a multibillion-dollar industry that involves the use of synthetic and plant-derived dyes. Maps Hair coloring
Application techniques
Off-scalp
Hair color is traditionally applied to the hair as a whole color. The modern trend is to use multiple colors to produce gradations or gradations, but not all work on one base color. These are referred to as:
- Highlight , in which parts of the hair are treated with a lightener
- Lit up , where hair parts are treated with darker hair color
- Splashlighting hair ribbon turns horizontally from ear to ear
There is also a newer dyeing technique like ombrÃÆ'Â ©, where dark hair on the crown and little by little becomes brighter towards the tip.
This is an off-the-scalp technique, and can be applied with the following methods:
- Thwart , in which pieces of foil or plastic film are used to separate the colored hair, especially when applying more than one color (This ensures the color is only applied to the desired strands of hair, and protect hair strands that are not meant to be dyed.)
- Cap , when a plastic cap is placed firmly in the head and strands are drawn with a hook (This method is not often done, with the exception of highlighting short hair.)
- Balayage , in which hair color is painted directly to the hair parts without the layers used to maintain the existing color (This method is increasingly popular because of its ability to look more natural.)
- Dipping or dipping the ends , similar to balayage because the colors are painted directly on the hair (This results in a more solid coverage level on the ends of the hair.)
All coloring techniques can be used with any type of color. For lightening, hair sometimes must be bleached before coloring.
On-scalp
Hair dyeing can also be applied to the scalp for a more solid coverage level
- Root touch-up , where the color is only applied to the most recent part of the re-growth (usually the first inch of the hair closest to the scalp) The root of the touch is repeated every 4-6 weeks when natural colors grow and become clear. People who color their hair to disguise the gray color often have this root touch.
- Versatile colors , where people want all their hair to be different solid colors
- Block coloring , where people want two or more colors applied to their hair, resulting in dimensions and contrast
All coloring techniques can be used with any type of color. For lightening, hair sometimes must be bleached before coloring.
Type
The four most common classifications are permanent , demi-permanen (sometimes called deposits only ), semi-permanent , and temporary .
Permanent
Permanent hair color generally contains ammonia and must be mixed with a developer or oxidizing agent to permanently change the color of hair. Ammonia is used in permanent hair color to open the cuticle layer so that the developer and the dye together can penetrate into the cortex. The developer or the oxidizing agent has various volumes. The higher the volume of the developer, the higher the "elevator" will become a person's natural hair pigment. A person with black hair who wants to achieve two or three lighter colors may require a higher developer while someone with lighter hair who wants to get darker hair will not be as tall as hair. The time may vary with permanent hair coloring but usually 30 minutes or 45 minutes for those who want to achieve the maximum color change.
Peri-permanent
The permanent hair color is a hair color containing alkaline agents other than ammonia (eg ethanolamine, sodium carbonate) and, while always used with the developer, the concentration of hydrogen peroxide in the developer may be lower than that used with permanent hair color. Because alkaline agents used in semi-permanent colors are less effective at removing natural hair pigments than ammonia, these products do not give light color to hair during immersion. As a result, they can not dye their hair to a lighter color than before coloring and less damaging the hair than their permanent counterparts.
Demi-permanents are much more effective in covering gray hair from semi-permanent, but less than permanent.
Demi-permanents has several advantages over permanent colors. Since there is essentially no removal (ie, removal) of natural hair color, the final color is less uniform/homogeneous than the permanent one and therefore more natural; they are softer on the hair and therefore safer, especially for damaged hair; and they wash from time to time (usually 20 to 28 shampoo), so root growth is less noticeable and if color change is desired, it is more easily achieved. Permanent permanent hair color is not permanent but darker color in particular can last longer than indicated on the package.
Semi permanent
Semi permanent hair coloring involves little or no developers, hydrogen peroxide or ammonia, and thus less damaging strands of hair. The number of reduced developers, whether peroxide or ammonia, means that previously damaged hair by applying permanent color or permanent rearrangement will likely not be damaged during the color application process.
The color of semi-permanent hair uses a compound with a lower molecular weight than that found in temporary hair dye. This dye penetrates the hair shaft only in part, because the number of developers used is reduced. For this reason, the color will survive repeated washing, usually 4-5 shampoos or several weeks, before experiencing significant fading or washing entirely.
Semi-permanent may still contain suspected carcinogenic p-phenylenediamine (PPD) or other related dyes. The US Environmental Protection Agency reports that in mice and rats that are chronically exposed to PPD in their diet, PPT appears to only weigh animal weight, with no sign of any other clinical toxicity observed in some studies.
The last color of each strand of hair will depend on its original color and porosity. Because of the hair color and porosity in the head and along the strands of hair, there will be subtle color variations throughout the head. It gives more natural-looking results than solid color, all colors are permanent. Because gray or white hair has a different initial color than other hairs, they will not appear as the same color as other hairs when treated with semi-permanent colors. If there is only a little white gray hair, the effect is usually enough for them to blend in, but when the gray spreads, a spot will appear where it will not be disguised as well. In this case, switching to permanent colors can sometimes be suspended by using semi-permanent as a base and adding highlights.
Semi permanent color can not brighten hair.
Temporary color
Temporary hair colors are available in various forms including rinsing, shampoo, gel, spray, and foam. Temporary hair color is usually brighter and more vibrant than semi-permanent and permanent hair color. It is most often used for hair coloring for special occasions such as costume parties and Halloween.
Pigments in hair color while high molecular weight and can not penetrate the cuticle layer. The color particles remain adsorbed (firmly attached) to the surface of the hair shaft and are easily removed with one shampoo. Temporary hair color can withstand hair that is too dry or damaged in a way that allows migration of pigments to the inside of the hair shaft.
Alternate colors
Alternative hair dye products are designed to create hair colors that are not usually found in nature. Available colors vary, such as green and fuchsia. A permanent alternative in multiple colors is available. Some of the shades of the colors are blacklight-reactive, and thus appear under the lighting of certain nightclubs, for example.
The chemical formula of alternative coloring dyes usually contains only color and has no developers. This means that they will only create the bright colors of the package if they are applied to bright blond hair. People with dark hair (medium to black brown) need to use a bleach before color application. Some people with blond hair can also benefit from previous bleaching. The golden, yellow and orange tones on the hair that are not bright enough can have an adverse effect on the results, especially with pink, blue and green. Although some alternate colors are semi-permanent, such as blue and purple, it may take several months to completely wash the color of the bleached or pre-bright hair.
Maintaining hair color
There are many ways that people can maintain their hair color, such as:
- Uses shampoo and color-protection conditioner
- Use a sulfate-free shampoo
- Use purple shampoos and conditioners to maintain or enhance blond color in their hair
- Uses UV absorbent signage
- Get deep-conditioning treatment to smooth and add luster
- Avoiding chlorine
- Uses heat shielding products before using style equipment
Alternative natural hair coloring
There are many natural ways to dye hair instead of having to use colors that contain some chemicals especially, some of which can cause skin irritation. Many natural hair coloring can be done at home. Alternative natural hair coloring can be done by using natural herbs such as henna. Different types of herbs can be used to achieve a certain color. Indigo or black walnut powder and dried gooseberry lead to black or dark color and chamomile and calendula leads to a darker blonde. Tea like black or hibiscus made of black tea leaves and shoemak flowers is also a natural way to dye hair, henna and derivatives are also used to dye hair, especially in Southeast Asia, to achieve a dark orange-reddish color. Although many natural hair colorings can be done at home, there are products in the market that come as purchased kits or salons that use natural ingredients in their hair color.
Note that although this is a natural way to dye hair, it is still important to wear gloves because the dye is being worked on.
Adverse effects
Hair coloration involves the use of chemicals capable of removing, replacing, and/or covering the pigments naturally found inside the hair shaft. The use of these chemicals can lead to various adverse effects, including temporary skin irritation and allergies, hair damage, discoloration and unexpected hair color. According to the International Agency for Research on Cancer (IARC), in vitro and in vivo studies (in exposed human populations) have shown that some hair dyes and many chemicals used in hair dyeing can be considered mutagenic and carcinogenic.
Skin irritation and allergies
In certain individuals, the use of hair dye may cause an allergic reaction and/or skin irritation. Individuals who are allergic to gluten for example, will need to be careful when buying hair color because of certain hair dyes including gluten. Gluten does not need to be digested to cause allergies. Skin contact with gluten may cause a reaction; therefore, cause allergies. The symptoms of this reaction may include redness, wounds, itching, burning sensations and discomfort. Symptoms are sometimes not immediately visible after application and color processing, but can also arise after hours or even days later.
To help prevent or limit allergic reactions, the majority of hair dye products suggest that clients perform patch tests before using the product. This involves mixing a small amount of color preparation and applying it directly to the skin for a period of 48 hours. If the irritation develops, the manufacturer recommends that the client not use the product.
European dermatologists, however, strongly advise against using such pre-use tests, as requiring additional risk (sensitization) and interpretation by ordinary people may not be accurate enough.
Hair Damage
Hair that has been damaged by excessive chemical exposure is considered over processed . It produces dry, rough and brittle hair. In extreme cases, the hair can be very damaged until broken. The main cases of hair loss are: Lack of moisture and oil, poor diet, stress, too much process or disease.
Skin discoloration
Skin and nails are made of a keratin protein similar to hair. That means that dripping, slipping and extra hair color around the hairline can produce patches of discolored skin. This is more common with darker hair color and those with dry absorbent skin. That is why it is recommended that latex or nitrile gloves are used to protect the hands.
This color change will disappear because the skin naturally renews itself and the top layer of skin is removed (usually takes several days or at most a week). How to prevent skin discoloration is to wear latex or nitrile gloves to protect the hands and also by applying a thin layer of petroleum oil or oil-based preparations around the hairline. Soft abrasives such as wet cake soda or toothpaste with a bit of toothpaste can also help remove the top layer of skin and dye (not just remove the dye). Removal of acetone and nail paints is not considered effective; laundry detergent can sometimes work just like a wet cigarette ash rubbed into a stained area.
Unwanted results
Several factors affect the final color of the hair after the staining process.
- For semi-permanent and permanent colors, the last color is a natural blend of hair color and dye color.
- Bleached hair often requires pre-pigmentation before color applications. Bleached brown hair immersion can produce gray hair or very pale (gray gray).
- Previously colored hair can react unexpectedly with subsequent color treatments.
- The use of an earlier shampoo that holds a plastic coating on the hair can block the action of the dye.
- The presence of minerals, salt, chlorine or other contaminants in the water used in the staining process
- Certain prescription drugs may alter hair chemistry
- Coloring dark hair to get the desired blond color requires bleaching, followed by secondary color treatment. Bleached hair can still have a yellow or copper color. Violet-based color can cancel yellow tone, and blue base color will cancel the orange color of copper.
- The hair porosity can affect the last color. Porous hair often absorbs more color, which sometimes results darker than expected.
Health issues
- Acetic lead salts (active ingredients in gradual evasion products such as the Greek formula) are toxic. Lead acetate trihydrate has also been shown to cause reproductive toxicity.
- Articles link the development of some forms of cancer (including leukemia, non-Hodgkin's lymphoma, bladder cancer, blood cancer, and multiple myeloma) with the use of hair color. More specifically, prolonged use of prolonged permanent hair dyes may double the risk of a person getting some type of blood cancer.
- In 2004 known human carcinogens, 4-aminobiphenyl or 4-ABP, were found in several commercial hair dyes. However, the evidence is limited and inconsistent for the relationship between cancer of hair dyes.
- Phenylenediamine is known to cause health problems, such as skin irritation. Exposure to phenylenediamine may occur during manufacture or during the use of hair dyes. According to the DuPont Product Safety Summary Sheet, Para-Phenyenediamine (PPD) is labeled as toxic and may cause adverse effects on aquatic organisms and may cause long-term effects in the aquatic environment.
Chemical permanent hair coloring
Permanent hair coloration requires three components: (1) 1,4-diaminobenzene (historically) or 2.5-diaminotoluene (current), (2) coupling agent, and (3) oxidant. This process is usually done under basic conditions. The oxidation dye mechanism involves three steps: 1) Oxidation of 1,4-diaminobenzene derivatives into the quinone state. 2) This diimin reaction with the coupler compound (more details below). 3) Oxidation of the resulting compound to produce the final dye.
Preparation (precursor dye) is in leuco (colorless) form. Oxidizers are usually hydrogen peroxide, and the alkaline environment is usually provided by ammonia. The combination of hydrogen peroxide and ammonia causes natural hair to become brighter, providing "empty canvas" for dye. Ammonia opens the pores of the hair shaft so that the dye can actually spread inside the fibers. These intermediates and couplings may undergo oxidation and coupling reactions as shown in the scheme below to form high molecular weight products, which are trapped in the hair matrix and can not be easily removed by washing.
Various combinations of primary intermediate and coupler compounds provide a spectrum of shades of hair color. Primary intermediates are aromatic compounds, such as 1,4-diaminobenzene or 4-aminophenol. The coupler compound (coupler) is a meta-substituted derivative of aniline. They come in three main classes based on the colors they produce when they react with the main intermediary.
- The blue coupler includes 1,3-diaminobenzene and its derivatives. Red couplers include phenol and naphthol, 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 a 3-aminophenol coupler provides a magenta-brown dye, while a 2.5-diaminotoluene combination with a 1-naphthol coupler provides purple dye.
- The green-yellow screw includes resorcinol, 4-chlororesorcinol, and benzodioxoles. These compounds produce a wide band absorption when they react to form a dye, allowing for a more natural hair color. The combination of 2.5-diaminotoluene with resortarol coupler provides a greenish brown dye.
The first step shows oxidation of p-phenylenediamine to quinonediimine (C 6 H 4 (NH) 2 ):
This species exists in equilibrium in the form of monoprotonate (C 6 H 4 (NH) (NH 2 ) not shown). The second step involves this quinonediimine attack on the coupler. In organic chemistry, this reaction is called electrophilic aromatic substitution:
In the third and final step, the product of the quinonediimine-coupler reaction oxidizes to the final hair dye.
It used to be believed that the dye forms the above reaction bond on the hair permanently. He then points out that the main reason that this reaction imparts a permanent color to the hair by producing larger dye molecules, which are locked in the hair.
Plant-based dye
Henna is an orange dye commonly used as a hair color deposits that its active component, lawone, binds to keratin. It is therefore considered semi-permanent for permanent, depending on the type of hair of a person. Most people will get a permanent color from the girlfriend, especially after the second dye. With repeated use the orange color accumulates to red and then redness. While "natural" girlfriends are generally red, variations exist. These variations usually contain ingredients from other plants and even synthetic dyes.
Indigo is a natural dye of the plant (Indigofera tinctoria, suffructicosa, or arrecta) which can be added to the girlfriend or layered on it to create a brown to black color in the hair. Henna is orange, and indigo is blue, so as a complement to the standard color wheel, the combined effect of two colors is to make a brown tone. Like henna, indigo may fade after one application, but become permanent in hair with repeated use.
Using plant-based colors like girlfriends can cause problems later when trying to do perm or permanent hair color. Some store-bought henna contains metallic salts that react to the hydrogen peroxide used in the hair brighteners. This can lead to unpredictable results, such as green or blue in hair. Henna is a healthy way to dye hair, as long as no metal salt is used.
Legal restrictions
Hair dye is a cosmetic compound that makes contact with skin during application. Due to this skin contact, there are several health risks associated with the use of hair dye. Thus, hair dye is set in the commercial market and, since new toxicity data is generated for some hair dyes and health risks found, some of these hair dyes are legally constrained from the cosmetic market.
The European Union is very strict with regards to health regulations. To ensure that hair dyes contain only safe substances, the European Commission adopted the Directive 2012/21/EU to limit the use of about 45 chemicals in hair dyes. The coloring instructions are part of a comprehensive set of rules and regulations, EU Cosmetics Directive 76/768/EC.
See also
- Human physical appearance
- Hairstyle
- Highlighting hair
- Punk Mode
- Chapatsu
References
Source of the article : Wikipedia
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