Among the constituents of the earth's surface layer, silicon (Si) is the next most element of oxygen. Since silicon has strong affinity for oxygen, it is not present in nature alone as a single substance, and usually exists as silica stone (sand, quartz, quartz). This silicone is reduced to make metallic silicon (metallic compound composed only of silicon atoms = silicon), and a complicated chemical reaction is added to produce synthetic resin "silicone" which combines inorganic and organic properties "is. Silicone has a siloxane bond (Si - O - Si) in which silicon and oxygen are alternately bonded as a main skeleton, and an organic group is bonded thereto, and it is resistant to high temperature and low temperature, and is not easily deteriorated even when exposed to ultraviolet rays , Water repelling, etc., various characteristics are exhibited. There are silicone in various conditions such as oil, resin, rubber, etc. It is utilized in all industrial fields such as aircraft, electronic equipment, chemistry, fiber, food, cosmetics, construction.