| 摘要 |
PROBLEM TO BE SOLVED: To balance the required property such as weight, elastic rate and internal loss with a shape effect by configuring the cabinet through the forming of a forming material containing an ultra-high crystalline polypropylene whose specific weight is a specific value or over and whose crystalline degree is a specific rate. SOLUTION: The ultra-high crystalline polypropylene used for the speaker cabinet has progressed stereoscopic regularity polymerization and a density of 0.91 or over and a degree of crystalline in excess of 70%, an elastic rate of about 40% and an improved bending strength by about, 25%. Since the crystalline speed is fast and uniform and fine crystal structure is obtained from the ultra-high crystalline polypropylene, the material withstands thermal deformation and excellent size stability is realized. The speaker cabinet with a sufficient strength and internal loss is obtained without addition of filler for property change. |
