alumina trihydrate

noun

: the trihydrate of alumina Al(OH)₃ used primarily for its flame-retardant properties

The influence of the inorganic flame retardants, including alumina trihydrate (ATH) and borax … on the mechanical properties and flammability of high density polyethylene has been studied.

—Journal of Technology and Science, 9 May 2010

Note: At approximately 350 degrees Fahrenheit, Al(OH)₃ decomposes to Al₂O₃·3H₂O, absorbing heat and releasing water vapor.

—abbreviation ATH compare aluminum hydroxide

Word History

First Known Use

1898, in the meaning defined above

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