| 摘要 |
PURPOSE:To obtain a lightweight, high elastic and high internal loss enclosure having excellent temperature resistant characteristics, by forming an acoustic equipment enclosure by using a kneaded material consisting essentially of polypropylene and flake graphite powder. CONSTITUTION:An enclosure for acoustic equipment is made of polypropylene alone or a mixture of polypropylene and polymethylmethacrylate PMMA and a mixture of a mixed material, obtained by mixing said synthetic resin with rubbery material, such as acrylonitrile butadiene rubber NBR, at need, and flake graphite powder. This graphite powder is oriented along the surface of the enclosure and preferably has a mean grain size of about 20mum and below. With regard to the compounding ratio of the graphite powder and resin, the improvement of the modulus of elasticity can be expected for example, when 10-90wt% graphite powder and 90-10wt% resin are used; moldability is not spoiled and the enbrittlement of moldings never occurs. The compounding ratio of PMMA and polypropylene is not important and 2-50wt% rubbery material is favorably mixed into the resin. |
