Silicone is a space-age material that has become increasingly popular as both a tool and medium for special effects.
Silicone has been popular as a medium for molding because it is a RTV (Room Temperature Vulcanizing) rubber, has high elasticity, and undergoes almost no distortion when returning to its initial form. It also has a high tear strength, an extremely long shelf life after curing, can withstand temperatures approaching 400 degrees F, and is non-sticking, avoiding the need for release agents. As resolution for film and TV became higher the lack of translucency in foam rubber became problematic and silicons and gelatins became prime candidates for more realistic looking effects.
Much of the pioneering work in the advancement of the use of silicone in the cosmetics industry is attributed to Gordon Smith. Gordon Smith was one of the earliest artists to commit to using silicone in major films. He and his crews worked out approaches to the problems of gel-filled appliances that many artists had worked on - his group was brave enough to use them where other proven techniques may have been safer. Ultimately, he made his silicone and matting powder available to other artists through Polytek.
Silicone may be divided into two categories, tin cure silicone and platinum cure silicone. Tin cure silicone gels and cures by pulling moisture from the air. Forms of tin cure silicone are readily available as bathroom caulking obtained from hardware stores. Platinum cure silicone is more expensive, but has a lower percentage of shrinkage during the cure phase. Platinum silicones are especially sensitive to contaminants that effect uniform gelling. Generally speaking, platinum silicone is preferred in Prosthetic makeup.