 Antimony is mainly used as its trioxide in making flame @-@ <unk> compounds . It is nearly always used in combination with halogenated flame retardants , with the only exception being in <unk> @-@ containing polymers . The formation of halogenated antimony compounds is the cause for the flame <unk> effect of antimony trioxide , due to reaction of these compounds with hydrogen atoms and probably also with oxygen atoms and OH radicals , thus inhibiting fire . <unk> for these flame @-@ <unk> applications include children 's clothing , toys , aircraft and automobile seat covers . It is also used in the fiberglass <unk> industry as an <unk> to <unk> <unk> for such items as light aircraft engine covers . The resin will burn while a flame is held to it but will extinguish itself as soon as the flame is removed . 
