Impact and sound absorbing material and sound absorbing structure
[Subject] The subject of the present invention is to provide a shock and sound absorbing material having a light weight, and demonstrating an excellent shock and sound absorbing performance. As a method for solving the subject, the present invention provides a shock and sound absorbing material 1 comprising a porous component 2 , and a surface material 3 which is laminated onto the porous component 2 , wherein the surface material 3 has at least one layer made of a stretchable paper material 5 . The shock and sound absorbing material 1 is installed on a cover panel 7 covering a sound source such as an engine cover, and the porous component 2 is set so as to face the cover panel 7 , with the surface material 3 being set so as to face the sound source, and form a cell structure between the cover panel 7 and the surface material 3.
1. A shock and sound absorbing material, comprising a porous component having a plural number of tubular open cells and a surface material which is laminated onto said porous component, wherein said surface material includes at least a first sound absorbing layer arranged on said porous component, a second sound absorbing layer laminated onto said first sound absorbing layer, and a surface skin layer, laminated onto said second sound absorbing layer, with said second sound absorbing layer being made of a stretchable paper material which is selected from the group consisting of creped paper, embossed paper, and creped and embossed paper wherein fine wrinkles are formed on the surface of said creped paper or said creped and embossed paper and a large number of projections are formed on said embossed paper or said creped and embossed paper and each of said creped paper, said embossed paper or said creped and embossed paper has a unit weight in the range of between 10 and 50 g/m 2 , and an airflow resistance of between 0.06 and 3.0 kPa·s/m, so as to adjust an air flow resistance of said surface material between 0.4 and 5.0 kPa·s/m.
2. A shock and sound absorbing material in accordance with claim 1 , wherein said first sound-absorbing layer and said surface skin layer are made of an air-permeable porous material.
3. A shock and sound absorbing material in accordance with claim 1 , wherein said porous component is a panel component made from a thermoplastic resin, having a large number of apertures which form a wall structure.
4. A shock and sound absorbing material in accordance with claim 1 , wherein a synthetic resin is coated onto at least one of the surface and the backside of said stretchable paper material, so as to adjust the airflow resistance of said stretchable paper material.
5. A sound absorbing structure, wherein said shock and sound absorbing material in accordance with claim 1 is installed on a cover panel covering a sound source, with said shock and sound absorbing material being arranged so that said surface material faces said sound source, and said porous component faces said cover panel.