Dielectric Materials - The Dielectric Constant, Uses, Synthetic Dielectrics, Breakdown

Dielectric materials are substances that have very low conductivity. That is, they are electrical insulators through which an electrical current flows only with the greatest of difficulty. Technically, a dielectric can be defined as a material with electrical conductivity of less than one millionth of a mho (a unit of electrical conductance) per centimeter.

In theory, dielectrics can include solids, liquids, and gases, although in practice only the first two of these three states of matter have any practical significance. Some of the most commonly used dielectrics are various kinds of rubber, glass, wood, and polymers among the solids; and hydrocarbon oils and silicone oils among the liquids.