Temporary Tattoo

A temporary tattoo is a non-permanent image on the skin resembling a real tattoo. Temporary tattoos can be drawn, painted, airbrushed, or glittered as a form of body painting, but most of the time these tattoos are transferred to the skin. Temporary tattoos of any kind are used for numerous purposes including self-expression and identification. For example, actors who wish to add to their character's distinctiveness might take temporary tattoos painted on the skin by hand or using stencils as part of their cosmetic ritual.

Henna tattoos
Henna tattoos, also known as Mehndi (Figure 1), is another form of temporary tattoo. Coming from a south Asian tradition, henna uses a paste made from the powdered leaves of the Henna plant, Lawsonia inermis. Its active dye, Lawsone, binds with the keratin in skin, fingernails, and hair. Traditional henna is drawn in delicate patterns on the hands and feet, but modern henna is applied in all sorts of designs anywhere on the body. Unlike other forms of temporary tattoos, henna does not allow for a full range of colors but only shades of reds, browns, and near-blacks. The paste is applied and left on the skin for several hours to stain. The stain will gradually fade away as the skin sheds. Henna tattoos can last days to over a month depending on application and aftercare.
 

Figure 1  Mehndi or henna on a hand.
However, caution should be taken as many products labeled henna are misleading. Fast-staining "black henna" can contain para-phenylenediamine (PPD) which can cause allergic reactions and scarring.

Temporary transfer tattoos
Old fashioned temporary tattoos, which were first made popular as inserts in bubble gum, were poor quality ink transfers that often resulted in blurry designs and could easily be washed or rubbed off. A very identifiable brand would be the fruit flavored chewing gum Fruit Stripe which has been popular with American children for many years. Nonetheless, these lick-and-peel temporary tattoos became a well-known piece of North America.
Modern temporary transfer tattoos are made of ink and glue, and last much longer than older temporary tattoos. In this process, the tattoo is applied to the outer surface of the skin and remains until such time as the image fades away (typically after 3–5 days) or is removed.
Temporary tattoos usually consist of five main elements: the front of the sheet of paper, the back of the sheet of paper, ink, glue and a protective plastic sheet. The front of the sheet is covered with a special coating upon which the tattoo image is printed with special inks. A layer of glue is then applied on top of the image. A thin, transparent plastic sheet is placed over the front of the sheet to protect the image and glue layer. The back of the sheet is left untreated and has a list of ingredients and instructions printed on it.
Transfer temporary tattoos are usually applied by removing the plastic sheet, placing the image face down against the skin and moistening the backing by wetting it thoroughly. The backing can then be carefully removed, leaving the image in place.
In 1980, temporary tattoos were created using different and exotic ink systems. 3M designed and developed a special coating called Micro-Fragrance that made scratch-n-sniff technology possible. The temporary tattoo industry adopted the scratch-n-sniff concept and a few companies, such as Dallas-based Highgate Products, released scented tattoos.
Around this time advances in ink and screen printing were also developed. These advances made the tattoos last longer and look more realistic. As tattoos quality increased, so did demand. People began seeing temporary tattoos as a product that could last and could be used outside of inexpensive giveaways.
Today, temporary tattoos are sold everywhere from vending machines to check-out counters at mass retailers to high-end boutiques and can be customized and printed through a color laser printer using specialty color laser transfer paper. A variety of tattoo designs exist; everything from Marvel superhero tattoos, to glitter designs, to Ed Hardy temporary tattoos for trendy adults and clubbing designs for young people.

Temporary airbrush tattoos
Temporary airbrush tattoos (Figure 2) are another kind of temporary tattoo. Like other forms of temporary tattoos, they are applied to the surface of the skin and do no damage to the skin. Airbrush tattoos are created by placing a stencil to the skin and delivering the tattoo ink or tribal airbrush tattoo paint with an airbrush. Unlike temporary transfer tattoos, the artist can control delicate elements of the temporary tattoo while it is being produced, which is more similar to the true permanent tattoo experience.
 
Figure 2 Airbrush tattoos on arms.
Temporary airbrush tattoos have been in existence since about 1998 and are largely used in marketing, advertising and the entertainment industry. Because of the constant research and development of airbrush equipment and inks, airbrush tattoos today so closely resemble real tattoos that many people cannot tell the difference.

Temporary airbrush tattoo removal
Most airbrush tattoo inks/paints are alcohol-based. Applying baby powder several times during the day will extend the life of the tattoo. Removal is done by applying oil or alcohol based product. Baby oil, mineral oil and suntan lotion work best. Isopropyl alcohol (rubbing alcohol) also works, but should be used with caution as it can dry and irritate the skin. They last from a couple of days up to a week depending on how often the area is washed and taken care of.

Temporary glitter tattoos
It is another kind of temporary tattoo.  It is alcohol free unlike an airbrush one.  It is the newest concept in temporary tattoos. Something are more colorful and unique than henna. It is shinny, sparkling, colorful, lovely and fun.  The glitter size is special ultra fine, cosmetic grade glitter powder, as well as hypoallergenic cosmetic glue, in glitter tattoo applications.  Glitter tattoos usually use stencil patterns to make as a guideline or can be drawn by a painting brush.  It can be really complicated and nice depend on how good you are.  The tattoos last for 3-14 days depend on conditions usage and kinds of the skin they are on. 
 
Figure 3 Glitter tattoos on arms, hands and shoulders.
It can be removed by oil based products such as baby oil or nail remover.

Temporary variants of permanent tattoos
Some tattoos applied with a tattoo gun may be less permanent or easier to remove; however, as these involve insertion of pigments under the skin and do not involve the removal or degradation of all materials involved, they cannot be considered completely temporary.

Photo Tattoo Simulation
Online Tattoo Simulators realistically simulate tattoo designs on body photographs. They require no supplies or removal process so are a fast alternative of seeing what a tattoo looks like before getting any work done.

Semi-permanent tattoos
Some practitioners offer tattoos that they claim to be temporary, but will last for a period of years rather than days. These are applied using a tattoo gun, and are therefore the closest substitute for the permanent tattoo experience, including the discomfort. These tattoos are supposed to gradually fade away over time, leaving no trace. Some tattoo artists claim that the inks are inserted closer to the surface, allowing them to gradually slough off, while others claim to use special inks that naturally disperse over time.
There is some discrepancy as to whether these semi-permanent tattoos are in fact "temporary tattoos" at all. In practice, semi-permanent tattoos have had mixed results, and caution would say that any tattoo performed by inserting pigment under the skin should be considered permanent.

Source: http://en.wikipedia.org/wiki/Temporary_tattoo