| 摘要 |
Magnesium hydroxide, in the form of fine powder, suitable as a filling agent for plastic materials having a capability to prevent ignition, containing particles or a thin coating material closed to the surface active agent, while the article size measured based on the laser rays diffraction,is less than 10 micrometers, the average size is greater than 0,8 micrometers and the content of ion type water soluble impurities is described by the following values when talking about the weight parts: Ca++ less than 1 000 ppm, Na+ less than 20 ppm, K+ less than 20 ppm, SO4- less than 1 500 ppm, Cl- less than 1000 ppm and the content of Mn, Cu and Ni closed to the values in the weight parts is as follows: MnO less than 100 ppm and CuO less than 10 ppm. The production of this material is based on that principle, that magnesium oxide gained as a result of hydropyrolysis of magnesium chloride solution, while the foreign substances are removed, is mixed with water, when a hydration is passing and the created magnesium hydroxide is removed with use of filtration, however the filter cake is being washed with the use of water containing no salts, and then this cake is dried.
|
