| 摘要 |
<p>PROBLEM TO BE SOLVED: To recycle the hard urethane foam, and reduce weight of a powdered vacuum heat insulating material and the scattering of the coarse particulate, by using a mixture of the urethane foam powder and a fiber material as a core material. SOLUTION: A vacuum heat insulating material 1 comprises, for example, a core material 2, a nonwoven fabric 3 having the air permeability, and a covering material 4 formed of a plastic laminate film. The core material 2 is prepared by adding the wet silica powder into the powder obtained by grinding the hard urethane foam for the surface reforming, and then adding and mixing a fiber material. Then the core material is filled in the nonwoven fabric 3 having the air permeability, and then dried, and further it is filled in the covering material, and evacuated under the reduced pressure to obtain the vacuum heat insulating material 1. In the vacuum heat insulating material manufactured as mentioned in the above, the hard urethane foam can be recycled, whereby the recycling of the heat insulating material used in a refrigerator becomes possible. Further the used paper mixed in the fiber material acts as a binder, so that the scattering of the coarse particulate can be reduced.</p> |
