Gel nails

There are two types of gel, hard gel and soft gel.

Hard gel gets its name because, once cured, it is tough enough to be made into a nail extension. Nail extensions are artificial nails created by using a nail product to extend the nail past the edge of the natural nail.

Soft gel refers to the gel products that are too soft to create a nail extension. This includes gel polishes and thicker gels meant for gel-overlay services. Gel polishes are used for the increasingly popular gel polish manicures. These manicures, when done by caring, experienced, and trained professionals, are gentle to the natural nail and the polish stays intact on the nail for at least a couple of weeks with high shine and no cracking, peeling or chipping.

The product used to create nail extensions using gel or gel nails is gel, not to be confused with acrylic nails, which are created using liquid monomer and polymer powder. All gel services are performed using some form of gel, which usually comes in pots of gel or bottles of gel polish. Gel also comes in a variety of colors. All forms of gel require curing, or hardening, under a UV (ultraviolet) light, which can be either a conventional bulb or LED lamp.

UV curing refers to the chemical process that occurs when photoinitiators within the gel itself are exposed to the UV or blue light. The energy from the light causes certain bonds in the initiator molecules to break, forming free radicals. The radicals begin attacking double bonds in the gel's component molecules, beginning a polymerization reaction which eventually encompasses all the molecules of the gel. Gels usually contain a mixture of acrylic monomers and oligomers, which combine to form long, interlocking chains during the polymerization, a process known as cross-linking. These long, bonded chains make the gel hard and chemically resistant. Usually, once the nail extension and/or gel manicure has been finished, there is a residual tacky layer, referred to as the "inhibition layer," that is removed by wiping with a preferably lint-free wipe soaked in high concentrate alcohol.

The process typically ends with an application of cuticle oil on all fingers, to bring back nourishment into the cuticle after harsh alcohol application.

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Wikipedia