Nail polish
Nail polish (nail varnish) is a lacquer applied to toenails or fingernails for appearance, but also as nail protection. Polishing afterward without adding another chemical layer is called nail buffing.
History
The Chinese used a colored lacquer, made from a combination of Arabic gum, egg whites, gelatin and beeswax. They also used a mixture consisting of mashed rose, orchid and impatiens petals combined with alum.[citation needed] This mixture, when applied to nails for a few hours or overnight, leaves a color ranging from pink to red. The Egyptians used reddish-brown stains derived from henna to color their nails as well as the tips of their fingers. Henna dyes are used to draw intricate, temporary designs on hands in Mehndi. Chou Dynasty of 600 B.C., Chinese royalty used gold and silver to enhance their nails. A fifteenth-century Ming manuscript cites red and black as the colors chosen by royalty for centuries previous.[citation needed] The Egyptians used nail color to signify social order, with shades of red at the top. Queen Nefertiti, the wife of the king Akhenaton, colored her finger and toe nails ruby red; Cleopatra favored a deep rust red.[citation needed] Women of lower rank who colored their nails were permitted only pale hues. Incas decorated their fingernails with pictures of eagles.[citation needed] Some Native Americans had colorful nails. It is unclear how the practice of coloring nails progressed following these beginnings. Portraits from the 17th and 18th centuries include shiny nails.[1] By the turn of the 19th century, nails were tinted with scented red oils and polished or buffed with a chamois cloth, rather than simply painted.[2] In addition, English and US 19th century cookbooks contained directions for making nail paints. In the 19th and early 20th centuries, women still pursued a polished, rather than painted, look by massaging tinted powders and creams into their nails, then buffing them shiny.[2] One such polishing product sold around this time was Graf’s Hyglo nail polish paste.[2] Some women during this period painted their nails using a clear, glossy varnish applied with camel-hair brushes.[2] When automobile paint was created around 1920, it inspired the introduction of colored nail enamels.[2] Nail polish contains nitrocellulose which is available in many different grades and is measured by viscosity. Nail grade nitrocellulose should be used for nail polish, as opposed to industrial grade which is available for use in furniture finishes, auto-paints and other various non-cosmetic lacquer finishes. Nail polish manufacturers are known to use industrial grade nitrocellulose covertly to save money, as it is half the price of the nail grade nitro.[citation needed]
Constituents
Most nail polishes are made of nitrocellulose dissolved in a solvent (e.g. butyl acetate or ethyl acetate) and either left clear or colored with various pigments. Basic components included are: film forming agents, resins and plasticizers, solvents, and coloring agents. Adhesive polymers (e.g. tosylamide-formaldehyde resin) ensure the nitrocellulose adheres to the nail's surface. Plasticizers (e.g. camphor) are chemicals that link between polymer chains, spacing them to make the film sufficiently flexible after drying. Pigments and sparkling particles (e.g. mica) add desired color and reflecting characteristics. Thickening agents (e.g. stearalkonium hectorite) are added to maintain the sparkling particles in suspension while in the bottle. Ultraviolet stabilizers (e.g. benozophenone-1) resist color changes when the dry film is exposed to direct sunlight. Nail polish ingredients often include toluene. Solvents such as toluene and xylene are petroleum-based products that have been linked to cancer. Formaldehyde (also called formalin) may cause allergic reactions in some people and is unsafe for use by asthmatic people. It is a carcinogen.
Nail polish makers are under pressure to reduce or eliminate potentially toxic ingredients, including phthalates, toluene, and formaldehyde.[3][4] In September 2006, several makers agreed to phase out dibutyl phthalate, which has been linked to testicular problems in lab animals and humans, in updated formulations.[4] Though some makers recently agreed to eliminate formaldehyde from their products, others still use the chemical.[3]
A recent development (ca. 2003) is water-based nail polish, which is based on an acrylic polymer emulsion (e.g. styrene-acrylate copolymer), and pigments similar to those used in watercolor paints.[citation needed] This is marketed as a more environmentally-conscious product, since nail polish is considered a hazardous waste by some regulatory bodies (e.g. Los Angeles Department of Public Works).[5] In this application, the solvent (water) does not completely evaporate as in the case of the traditional nail polish; part of the water is absorbed through the fingernail.
Nail polish in fashion
Nail polish is traditionally worn by women, but is now gaining in popularity for men as well. Traditional colors for nail polish were red, pink and brown, and now can be found in most any color. French manicures traditionally mimic the color of natural nails, with a clear, beige or soft pink polish on most of the nail and a white finish at the tips. Now, Reverse French Manicure is popular too. Black (and other dark nail polish shades) has been popular with goths and punks of both genders since the 1970s, but has recently gained acceptance as a very chic color. Other colors that are popular in fashion are bright colors, such as: hot pinks and purples. OPI, the nailpolish company, produces many of the brighter colors.
Some types of polish are advertised to cause nail growth, make nails stronger, prevent nails from breaking, cracking and splitting and stop nail biting. Nail polish may be applied as one of several components in a manicure. However, some nail treatments contain ingredients such as ammonium hexafluorophosphate.
Nail polish remover
Nail polish is easily removed with nail polish remover, which is basically an organic solvent but may also include oils, scents and coloring. Nail polish remover packages may include individual felt pads soaked in remover, a bottle of liquid remover that can be used with a cotton ball, and even containers filled with foam and remover that can be used by inserting a finger into the container and twisting until the polish comes off.
The base solvent in nail polish remover is usually acetone or ethyl acetate. Acetonitrile has been used, but is more toxic: two cases have been reported of accidental poisoning of young children by acetonitrile-based nail polish remover, one of which was fatal.[6][7] Acetonitrile has been banned in cosmetics (including nail polish removers) in the European Economic Area since 17 March 2000.[8]
See also
References
- ^ Chemical & Engineering News, August 11, 2008, p. 42, "Nail Polish"
- ^ a b c d e "History of Nail Care." Originally published in Nails magazine, 2007.
- ^ a b Nail polish manufacturers remove potentially harmful chemicals
- ^ a b Singer, Natasha. "Nail Polish Makers Yield on Disputed Chemical." New York Times (Sept. 7, 2006).
- ^ LA Dept of Public Works website
- ^ Caravati, EM (1988). "Pediatric cyanide intoxication and death from an acetonitrile-containing cosmetic". J. Am. Med. Assoc. 260 (23): 3470–73. doi:10.1001/jama.260.23.3470. PMID 3062198.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ International Programme on Chemical Safety (1993), Environmental Health Criteria 154. Acetonitrile, Geneva: World Health Organization
- ^ Twenty-Fifth Commission Directive 2000/11/EC of 10 March 2000 adapting to technical progress Annex II to Council Directive 76/768/EEC on the approximation of laws of the Member States relating to cosmetic products. OJEC L65 of 14 March 2000, pp. 22–25.
- Charles Panati , Extraordinary Origins of Everyday Things Harper & Row Copyright 1987
- Vanni Contingo, Article published in COSMO Magazine, copyright 2007
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