Abstract
As the flame-retardants for eco-wise and cables synthesis-Mg（OH）2 have been used widely. However this synthesis-Mg（OH）2 is less ecological and costly，because a lot of energy are consumed in the synthesis process. This time, author has tried to replace synthesis-Mg（OH）2 with natural-Mg（OH）2，and has succeeded in improving the characteristics of natural-Mg（OH）2 by crushing original stones to extremely small pieces and coating fatty acid onto those surfaces by dry method. And，by the detailed experimental results, it is clarified that the performance of the compound with natural-Mg（OH）2 is nearly equivalent to that of the compound with conventional synthesis-Mg（OH）2. In the next place，author has found out that it is possible to reduce the quantity of Mg（OH）2 which is necessary to keep the compound flame retardant，by adding small quantity of red phosphorus. And also，it was verified by the LCA analysis that a lot of CO2 emissions can be cut down by replacing synthesis-Mg（OH）2 with natural-Mg（OH）2 and reducing the quantity of Mg（OH）2 by half. Additionally，author has made sure that the PH3 gas from red phosphorus are harmless to the health，by researching the literature on that subject.
