MAGNESIUM HYDROXIDE, METHOD FOR PRODUCTION THEREOF AND FLAME-RETARDER COMPRISING THE MAGNESIUM HYDROXIDE, AND FLAME-RETARDANT RESIN COMPOSITION CONTAINING THE MAGNESIUM HYDROXIDE

摘要

A magnesium hydroxide material having a great specific surface area is provided. A method for producing the above magnesium hydroxide material, which comprises immersing a magnesium-containing material in an acidic solution to thereby decompose chemically, adding an alkali solution to the resultant acid solution to prepare a primary alkali solution being weakly alkaline, removing impurities in the primary alkaline solution, adding an alkaline solution to the resultant primary alkaline solution, to prepare the secondary alkaline solution being strongly alkaline, and precipitating magnesium hydroxide in the secondary alkaline solution.