Nail polish, or nail varnish, is a lacquer applied to human fingernails or toenails to decorate and/or protect the nail plate.

Constituents



Pink nail polish and applicator.
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 that 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 (formalin) may cause allergic reactions and is unsafe for use by asthmatic people. It is a carcinogen.
Nail polish makers are under pressure to reduce or eliminate toxic ingredients, including phthalates, toluene, and formaldehyde. 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.Singer, Natasha. "Nail Polish Makers Yield on Disputed Chemical." New York Times (Sept. 7, 2006). Some makers eliminated formaldehyde from their products, others still use it.Nail polish manufacturers remove potentially harmful chemicals
Water-based nail polish 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 an environmentally-conscious product, since nail polish is considered a hazardous waste by some regulatory bodies (e.g. Los Angeles Department of Public Works).LA Dept of Public Works website 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.
[edit]Nail polish in fashion

Traditional colors for nail polish were red, pink and brown, but modern nail polish can now be found in any color. French manicures traditionally mimic the color of natural nails, using a clear, beige or soft pink polish on most of the nail with a white finish at the tips.
Black has been a popular color of nail polish with goths, emo and punks of both genders since the 1970s, However Black and dark nail colours were a huge trend as early on as the 1930's.
Nail polish forms and techniques have evolved beyond painting solid colors. One such example is the nail stamp products, which involve stamping colored polish designs to nails. Popular design examples include as cheetah prints, flowers, and animal characters. Youtube is booming with thousands of nail art tutorials. There are also polishes that give a "crackled," intricate design when applied. Another new nail trend is magnetic nail polish. Upon application you hold the magnet that comes with it over the varnish for a wavy effect. Another form of nail polish are nail polish strips, polished stickers for nails. There are also nail decorations, such as rhinestones.
Some types of polish are advertised to cause nail growth, make nails stronger, prevent nails from breaking, cracking and splitting, and to stop nail biting. Nail polish may be applied as one of several components in a manicure.
Clear varnish is a transparent and glossy layer which can make the nails appear clean and shiny. This type of nail polish can be used over other varnish for gloss or by itself, as can glitter nail polish. Similar to a clear varnish is an acrylic gel polish. This polish is much like the gel products used in nail salons, which is essentially a strong, clear top coat typically applied over a colored polish. The acrylic gel polish is more than just a glossy layer over nails; the polish gives the underlying color polish support and protection from being easily chipped.
[edit]Nail polish remover

Nail polish is removed with nail polish remover, which is 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 or cotton pad, and even containers filled with foam that can be used by inserting a finger into the container and twisting until the polish comes off.
The most common type of nail polish remover contains acetone. It is powerful and effective, but is harsh on skin and nails, which can even make them more brittle.[citation needed] Acetone is considered a volatile organic compound by the U.S. Environmental Protection Agency.U.S National Safety Council, Environment Writer, 2006 It can also be used to remove artificial nails, which are usually made of acrylic.
The common alternative is simply called "non-acetone nail polish remover", which usually contains ethyl acetate. This is a less aggressive solvent and can therefore be used to remove nail polish from artificial nails.