Outer sole and shoes

Abstract

The present invention provides an outer sole light in weight and excellent in abrasion resistance. The outer sole of the present invention is formed out of a polymer composition with a specific gravity of 0.95 or less, which contains an olefin resin and a styrene elastomer, wherein a storage elastic modulus [E′] and a loss coefficient [tan δ] in a dynamic viscoelasticity measurement (20±3° C., 10 Hz) are 100 MPa to 500 MPa and 0.2 or less respectively, and a maximum tensile stress is 30 MPa or more. The olefin resin contains an ethylene polymer and a propylene polymer, for example. The styrene elastomer contains an α-methyl styrene.butadiene copolymer, for example. A flaw is hardly occurred on the outer sole in use, so that the outer sole is excellent in abrasion resistance.

1 . An outer sole being disposed on the bottom face of shoes, comprising:
 a polymer composition with a specific gravity of 0.95 or less which contains an olefin resin and a styrene elastomer;   wherein a storage elastic modulus [E′] and a loss coefficient [tan δ] in a dynamic viscoelasticity measurement (20±3° C., 10 Hz) are 100 MPa to 500 MPa and 0.2 or less respectively, and a maximum tensile stress is 30 MPa or more.   
   
   
       2 . The outer sole of shoes according to  claim 1 , wherein the olefin resin and the styrene elastomer are blended by 40 parts by mass to 60 parts by mass and 40 parts by mass to 60 parts by mass respectively with respect to 100 parts by mass of a total amount of the olefin resin and the styrene elastomer. 
   
   
       3 . The outer sole of shoes according to  claim 1 , wherein the olefin resin contains a mixture of an ethylene polymer and a propylene polymer. 
   
   
       4 . The outer sole of shoes according to  claim 3 , wherein the blending ratio (mass ratio) of the ethylene polymer and the propylene polymer is 1:5 to 4:1. 
   
   
       5 . The outer sole of shoes according to  claim 1 , wherein the styrene elastomer contains an α-methyl styrene.butadiene copolymer. 
   
   
       6 . The outer sole of shoes according to  claim 1 , wherein a convex stud portion is formed on the front face. 
   
   
       7 . Shoes being provided with the outer sole according to  claim 1 .