Antimony Trioxide

Antimony trioxide is a kind of fire retardant, which add to resin, synthetic rubber, canvas, paper and coating. It is white powder or  small cylinder. It dissolve in concentrated hydrochloric acid, sulfuric acid, aqueous alkali and hot tartaric acid solution.

Antimony Trioxide

Purity: 99.99%, 99.999%

CAS No.: 1309-64-4 EINECS No.: 215-175-0 Molecular Formula: Sb2O3 Molecular Weight: 291.50
Melting Point:656℃ Boiling Point: 1456℃ Density: 5.67 Refractive Index: 2.087


Antimony trioxide is additive flame retardant, which use with other flame retardant and antismoke agent. Its initial step is liquation when first ignition and form protective film to isolate the air on the surface of material. It through absorbing heat inside to reduce ignition temperature. In high temperature situation antimony oxide gasify and dilute oxygen concentration in air, which is the inflaming retarding.

Sb2O3 is raw material for mordant, opalizer and antimony salts. It is also an additive in enamelware industry, which can enhance opaqueness and surface gloss of enamel.  In glass industry, it replace arsenious acid as decolorising agent.

Antimony oxide is a common condensation catalyst for petrochemical engineering and synthetic fibre. Its usage in potassium diphenyl glycol is about 0.03%.

Sb2O3 is the earliest flame retardant, which fit for epoxy resin, polyurethane, polystyrene, polyvinyl chloride and polyester.