Kevlar, with its composition para aramid (many types K29，K49，K49AP~~~) , is the brand name of DuPont which develop an aramid fiber material product since 1970s. With the different chemical structure, aramid is put into two kinds ----para aramid (PPTA) and meta aramid (PMIA).
Its main feature is with permanent flame retardant and high temperature resistance (Limit oxygen index>28), so it is usually applied in fire fighting field such as entry suit, fireproof blanket, fireproof hood and so on. The surface of the material will be thickened when the fire is burned, and the seal is strengthened, no broken, no poisonous gas and no melting.
With the other outstanding feature, para aramid material is with high tenacity(5 times higher than the same quality of steel) and bullet proof function, it is usually used for military and police guard. It is named “armoured guard” in military and police field. "para aramid composite armor" laminated plate and steel, aluminum, it has been widely used not only in tanks, armored vehicles, bulletproof vests, and also for nuclear powered aircraft carriers and missile destroyers.
In police guard, para aramid material is the most ideal material for bullet proof vests. Instead of nylon and glass fiber, para aramid materials have the excellent protection ability, also have good flexibility and is easy and comfortable to wear.