Antimony trioxide
CAS 1309-64-4
EC 215-175-0
Formula O3Sb2
MW 291.52 g/mol
Salts & Minerals Plastics & PolymersElectronicsBuilding & ConstructionTextile, Leather & PaperAutomotiveAerospace & Defense Flame Retardancy
Description
Antimony trioxide (CAS 1309-64-4, EC 215-175-0, Sb2O3) is an inorganic mineral compound sold under trade names including Timonox, Antox, and product codes a1530, a1582, and a1588lp. It carries no E-code designation and is classified within the salts and minerals category.
In flame retardant systems, antimony trioxide functions as a synergist rather than a standalone retardant, reacting with halogenated compounds during combustion to generate antimony halides that interrupt the radical chain reactions sustaining a flame. This mechanism is applied in PVC cable insulation, polyester textiles, and epoxy-based printed circuit board laminates across electronics, automotive, and aerospace manufacturing.
Antimony trioxide is available in standard and low-particle grades, including the fine-particle a1588lp grade suited to demanding polymer applications. It falls under REACH regulation and requires a current Safety Data Sheet for EU procurement. Packaging formats typically include 25 kg bags, with bulk options available depending on supplier and grade.
In flame retardant systems, antimony trioxide functions as a synergist rather than a standalone retardant, reacting with halogenated compounds during combustion to generate antimony halides that interrupt the radical chain reactions sustaining a flame. This mechanism is applied in PVC cable insulation, polyester textiles, and epoxy-based printed circuit board laminates across electronics, automotive, and aerospace manufacturing.
Antimony trioxide is available in standard and low-particle grades, including the fine-particle a1588lp grade suited to demanding polymer applications. It falls under REACH regulation and requires a current Safety Data Sheet for EU procurement. Packaging formats typically include 25 kg bags, with bulk options available depending on supplier and grade.
Physical Properties
| Melting Point | 655 °C |
| Boiling Point | 1425 °C |
| Density | 5.2 g/cm³ (solid) |
| Flash Point | 1550°C subl. |
| Appearance | White or gray mineral, sometimes pale red, white streak and adamantine or silky luster. Mohs hardness 2–3. |
| Color | White |
| Odor | wh. cubic or orthorhombic cryst., odorless |
| Form | powder |
| Water Solubility | Slightly soluble. <0.1 g/100 mL at 20 ºC |
| Vapor Pressure | 13.3 hPa (660 °C) |
Trade & Regulatory
| HS Code | 28258000 |
| Storage Class | 13 - Non Combustible Solids |
| WGK (Germany) | 2 |
Other Names
a1530Antoxa1582a1588lpTimonoxSB OXIDEExiteliteC.I. 77052Thermoguard S
Related Products
Raw Materials
Derivatives
Need a chemical? Get a quote within 24 hours.