In the last few years, aromatic polyamides (aramides) have be- come increasingly important. These are made from terephthalic or isophthalic acid, and m- or p-phenylenediamine. Du Pont developed two aramide fibers, Kevlar@ and Nomex@, and began production in the late 1960s. Since then, other production facilities have been started by other firms in the USA, Western Europe, Japan, and the CIS. Aramides are mainly used in the rubber industry. The properties of the aramides are so different from those of the aliphatic polyamides, e. g., heat resistance and low flammability, that they are not classified as nylons.