Fake nails

Artificial nails, also known as acrylics, fake nails, false nails, fashion nails, nail enhancements, nail wraps, or nail extensions, are coverings placed over fingernails as fashion accessories. Some artificial nails attempt to mimic the appearance of real fingernails as closely as possible, while other designs may deliberately stray in appearance from real fingernails. Artificial nails are made from a wide variety of materials. Unlike most manicures, Artificial Nails require constant up keeping, and is recommended that you get a "fill" every 2 weeks.

The artificial nails are not a replacement, but an extension for natural nails. There are two main approaches to creating artificial nails—tips and forms. Tips are made of lightweight plastic plates that are "nail"-shaped. They are glued on the end of the natural nail and acrylic or gel or a combination of both is then applied over the entire nail. Tips are now available in many different colors and designs, ranging from simple colors such as yellow or blue to flamboyant designs such as animal prints and mixed metallic colors. Forms are fitted over the nail and then an artificial nail is sculpted out of acrylic or gel and the form is removed and then properly shaped and buffed to a shine.

One popular material commonly called "Polymethyl methacrylate acrylics" is a mixture of a polymer powder and a liquid monomer (e.g. ethyl methacrylate). The mixture starts to harden in 20–30 seconds after application and continues to harden to final hardness typically within fifteen minutes. Powder and liquid acrylics can be removed by using a variety of solvents (usually acetone is used). Usually it takes 20 to 30 minutes to remove the nail while using a nail file to help take off each layer of the artificial nail.

Another material, commonly called "UV Top Coat" (in correct chemical terms a polymer resin) cures under ultraviolet light. Depending on brand these can show a broader variety of quality and properties (flexibility, strength, etc.) but may be more expensive. They generally cannot be removed by organic solvents, but only be removed by filing (or left to grow out with the natural nail). There are, however, a variety of soak off UV gels which can be quickly and easily removed using acetone.

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Wikipedia