KEVLAR, originally named Kevlar in English, is also translated as Kevlar or Kevlar. It is the brand name of an aramid fiber material product developed by DuPont Company in the United States. The original name of the material is "poly (p-phenylene terephthalamide)", and the repeating unit of the chemical formula is -[-CO-C6H4-CONH-C6H4-NH-]- the amide group attached to the benzene ring is para-structure (meta-structure is another product named Nomex, commonly known as fireproof fiber).

in 196s, DuPont company of the United States developed a new aramid fiber composite-aramid fiber 1414, which was commercialized in 1972 and registered as Kevlar. The models are divided into K29, K49, K49AP and so on.

because of its low density, high strength, good toughness, high temperature resistance, and easy processing and molding, this new material has attracted people's attention because its strength is five times that of steel with the same quality, but its density is only one-fifth of that of steel (Kevlar density is 1.44 grams per cubic centimeter, and steel density is 7.859 grams per cubic centimeter). Because Kevlar brand products are tough and wear-resistant, both rigid and flexible, they have the special ability of invulnerability. In the military, it is called "Zhuang Jia Wei Shi".