WESTCO™ ATO Twinkling Star Brand Antimony Trioxide CAS# 1309-64-4

WESTCO ATO is used as a fire retardant in rubber, plastics, wire & cable and other composites.  It must be used in conjunction with a halogen source, for example a chlorinated paraffin to be effective.

Packaging: 25 Kg woven plastic bags, Supersacks. Other packaging available

Storage: Keep cool and dry in closed original packaging with adequate ventilation. Avoid exposure to direct sunlight, 3 year shelf life.


Appearance: White crystalline powder

99.50% Min.


0.10% Max.


0.006% Max.


0.06% Max.


0.002% Max.

*325 mesh sieve residue

0.05% Max.

*Particle size

0.90 - 1.60 µm


93.0% Min.

Specific gravity at 20°C

5.20 typical

*Actual tech data / technical data values reported on Certificate of Analysis

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      • Western Reserve Chemicals
      • 60 S. Seiberling Street
      • Akron, OH 44305

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