Patent ID: 11912009
Assignee: ARCHEM INC.
Field: Surface technology, coating (Chemistry)
Classification: CPC B  G | IPC B  G

Claim 0:
1. A sound insulation material comprising
a first layer constituted by a polyurethane foam,
a second layer that is laminated on a surface of the first layer, the surface being located on a first side, and that is constituted by a sheet-shaped member made from a material other than polyurethane,
a third layer that is laminated on a surface of the second layer, the surface being located on the first side, that comprises a polyurethane foam, and that, over its entirety, has a higher density than a density of at least a portion of the first layer,
wherein at least a portion of the first layer has a density of 15 kg/m3 or less,
the minimum value of the density of the third layer is 300 kg/m3 or more,
the second layer is constituted by a non-woven fabric, and
a thickness of at least a portion of the first layer is 10 to 50 times a maximum value of a thickness of the third layer.