Molded sonic absorber

Abstract

The present invention provides a molded sonic absorber excellent in sound absorption action for a sound with a wavelength in a human audible range. More specifically, the present invention provides a molded sonic absorber obtained by mixing: a chip of a cellulose acetate fiber as a component (A) ; a chip of a polyurethane foam as a component (B); and a urethane resin-based adhesive as a component (C), followed by compression molding.

1 . A molded sonic absorber comprising: 
 (A) a chip of one of an organic fibrous body and an inorganic fibrous body; and    (B) a chip of one of an organic porous body and an inorganic porous body.    
   
   
       2 . A molded sonic absorber comprising: 
 (A) a chip of one of an organic fibrous body and an inorganic fibrous body;    (B) a chip of one of an organic porous body and an inorganic porous body; and    (C) a binding agent.    
   
   
       3 . The molded sonic absorber according to  claim 1 , wherein the organic fibrous body as the component (A) contains a polymer fiber that is not thermoplastic.  
   
   
       4 . The molded sonic absorber according to  claim 1 , wherein the organic fibrous body as the component (A) contains a cellulose acetate fiber.  
   
   
       5 . The molded sonic absorber according to  claim 1 , wherein the component (A) contains at least one of a short fiber and a continuous fiber and the chip has a maximum length of 20 mm or less.  
   
   
       6 . The molded sonic absorber according to  claim 1 , wherein the organic fibrous body as the component (A) contains a cellulose acetate fiber and the cellulose acetate fiber is derived from a cigarette filter.  
   
   
       7 . The molded sonic absorber according to  claim 1 , wherein the component (A) contains paper.  
   
   
       8 . The molded sonic absorber according to  claim 7 , wherein the paper is derived from a cigarette filter.  
   
   
       9 . The molded sonic absorber according to  claim 1 , wherein the porous body as the component (B) contains a foaming polymer.  
   
   
       10 . The molded sonic absorber according to  claim 1 , wherein the porous body as the component (B) contains a polyurethane foam.  
   
   
       11 . The molded sonic absorber according to  claim 1 , wherein the chip of the porous body as the component (B) has a maximum length of 20 mm or less.  
   
   
       12 . The molded sonic absorber according to  claim 1 , wherein the chip of the porous body as the component (B) comprises one of a trim in urethane foaming and a recycled product of a wasted heat-insulating material.  
   
   
       13 . The molded sonic absorber according to  claim 1 , wherein the component (A) accounts for 80 to 20% by mass and the component (B) accounts for 20 to 80% by mass.  
   
   
       14 . The molded sonic absorber according to  claim 13 , wherein the component (A) contains paper at a content of less than 80% by mass.  
   
   
       15 . The molded sonic absorber according to  claim 1 , wherein a content of the binding agent as the component (C) is 10 to 30 parts by mass with respect to 100 parts by mass of the total of the component (A) and the component (B).  
   
   
       16 . The molded sonic absorber according to  claim 1 , wherein the molded sonic absorber has a density of 0.05 to 0.2 g/cm 3 .  
   
   
       17 . The molded sonic absorber according to  claim 1 , wherein a vertical incidence sound absorption coefficient at 630 Hz measured according to the vertical incidence sound absorption measurement method (JIS A1405) is 0.2 or more.  
   
   
       18 . The molded sonic absorber according to  claim 1 , wherein a vertical incidence sound absorption coefficient at 630 Hz measured according to the vertical incidence sound absorption measurement method (JIS A1405) is 0.4 or more.  
   
   
       19 . The molded sonic absorber according to  claim 1 , wherein a vertical incidence sound absorption coefficient in a frequency range of 400 to 1,000 Hz measured according to the vertical incidence sound absorption measurement method (JIS A1405) is 0.4 or more.  
   
   
       20 . The molded sonic absorber according to  claim 1 , wherein a vertical incidence sound absorption coefficient in a frequency range of 550 to 800 Hz measured according to the vertical incidence sound absorption measurement method (JIS A1405) is 0.4 or more.  
   
   
       21 . A laminated sonic absorber comprising two or more layers including a molded sonic absorber according to  claim 1  and a foam in a form of a laminate.  
   
   
       22 . The laminates sonic absorber according to  claim 21 , further comprising at least one of a support layer and a protective layer on one or both sides of the laminate of the two or more layers including the molded sonic absorber and the foam.  
   
   
       23 . The laminated sonic absorber according to  claim 22 , wherein the foam serves as an intermediate layer with molded sonic absorber layers on both sides of the intermediate layer.  
   
   
       24 . An interior material for an automobile using one of the molded sonic absorber and the laminated sonic absorber according to  claim 21 .  
   
   
       25 . A building material using one of the molded sonic absorber and the laminated sonic absorber according to  claim 21 .  
   
   
       26 . A sound absorption structure using one of the molded sonic absorber and the laminated sonic absorber according to  claim 21.