Flame retardants, as the name suggests, are things used to stop burning, which are generally chemicals. There are many types of flame retardant mechanisms of flame retardants, mainly including endothermic effect, covering effect, inhibition of chain reaction, and non-combustible gas suffocation. The flame retardant mechanism of endothermic action is simply that it absorbs the heat of the burning material and reduces the momentum of the combustion. The covering effect is to cut off the contact between the combustible substance and the oxygen in the air through the flame retardant, so as to prevent the combustion. The suffocation effect of incombustible gas is that when burning, the flame retardant emits incombustible gas to replace the combustible gas, so that the combustible material cannot be burned.