| 摘要 |
PURPOSE:To make it possible to manufacture vibration damping and sound absorbing material by a method wherein the material mainly consists of polyurethane foam and chips, flocks, waste plastic or the like may well be mixed with the chip, and a layer of mixture of the chips and urethane prepolymer and a layer of the chips, urethane prepolymer and asphalt are heated with steam. CONSTITUTION:The mixing ratio of chip to urethane prepolymer by weight is normally 90:10-50:50. In addition, asphalt is added to the mixture of chips and urethane prepolymer. The additional amount of asphalt is normally set so that the ratio of the mixture of chips and urethane prepolymer to asphalt by weight is about 90:10-30:70. The mixture of chips and urethane prepolymer (a mixture A) and the mixture of chips, urethane prepolymer and asphalt (a mixture B) are respectively applied in a mold having the predetermined shape. After that, steam is poured in the mold so as to bring the steam in contact with the urethane prepolymers in the mixtures A and B in order to heat them, resulting in solidifying the prepolymers and consequently bonding chips. Thus, a molded product, in which a sound absorbing layer consisting of the mixture A and a vibration damping layer consisting of the mixture B are made into an integral body, is obtained. |
