Flexible polyurethane foam for tires, noise reducing device and tire

Abstract

The present invention is to provide a flexible polyurethane foam for tires that can effectively suppress damages, such as chips and cracks, and deformation, such as compression (permanent set in fatigue), even when attached to an inner face of a tire by using a band member. A flexible polyurethane foam for tires 5 which is attached to a gap between a tire and a wheel rim, wherein a density is in the range from 7 to 40 kg/m 3 and a tear strength (N/cm) per unit density (kg/m 3 ) is 0.30 or more, a noise reducing device with the flexible polyurethane foam for tires 5 fixed to a ring-shaped band member, and a tire 10 with the noise reducing device attached thereto.

1 . A flexible polyurethane foam for tires which is attached to a gap between a tire and a wheel rim, wherein a density is in the range from 7 to 40 kg/m 3  and a tear strength (N/cm) per unit density (kg/m 3 ) is 0.30 or more. 
   
   
       2 . The flexible polyurethane foam for tires of  claim 1 , wherein the number of cells is 25 cells/25 mm or more. 
   
   
       3 . The flexible polyurethane foam for tires of  claim 1 , which is attached to an inner face of a tire by using a band member. 
   
   
       4 . The flexible polyurethane foam for tires of  claim 1 , wherein the tear strength (N/cm) per unit density (kg/m 3 ) is 0.35 to 0.90. 
   
   
       5 . A noise reducing device, comprising the flexible polyurethane foam for tires of  claim 1  which is fixed to a ring-shaped band member. 
   
   
       6 . A tire, comprising the noise reducing device of  claim 5 .