Rubber Composition And Pneumatic Tire Using The Same

Abstract

This invention provides a rubber composition comprising 1-10 parts by mass of sulfur and 0.1-10 parts by mass of a compound represented by the following general formula (1) or a composition containing the compound as a main component based on 100 parts by mass of a rubber component as well as a pneumatic tire in which at least one of a carcass (4) and a belt (6) includes a layer composed of steel cords covered with a coating rubber, characterized in that the above rubber composition is used as the coating rubber covering the steel cords in at least one of the carcass (4) and the belt (6): (wherein R represents a divalent aliphatic group having a carbon number of 1-16 or a divalent aromatic group).

1 . A rubber composition comprising 1-10 parts by mass of sulfur and 0.1-10 parts by mass of a compound represented by the following general formula (1) based on 100 parts by mass of a rubber component: 
     
       
         
         
             
             
         
       
       (wherein R represents a divalent aliphatic group having a carbon number of 1-16 or a divalent aromatic group). 
     
   
   
       2 . A rubber composition according to  claim 1 , wherein the compound represented by the general formula (1) is a compound represented by the following general formula (2): 
     
       
         
         
             
             
         
       
       (wherein R represents a divalent aliphatic group having a carbon number of 1-16 or a divalent aromatic group). 
     
   
   
       3 . A rubber composition comprising 1-10 parts by mass of sulfur and 0.1-10 parts by mass of a composition containing 60-100 wt % of the compound represented by the general formula (2), 0-20 wt % of a compound represented by the following general formula (3) in which n is 2, 0-10 wt % of a compound represented by the following general formula (3) in which n is 3 and 0-10 wt % of a compound represented by the following general formula (3) in which n is 4-6 based on 100 parts by mass of a rubber component: 
     
       
         
         
             
             
         
       
       (wherein R is a divalent aliphatic group having a carbon number of 1-16 or a divalent aromatic group, and n is an integer of 2-6). 
     
   
   
       4 . A rubber composition according to  claim 1 , wherein R in the general formula (2) is an alkylene group having a carbon number of 2-10 or phenylene group. 
   
   
       5 . A rubber composition according to  claim 1 , wherein R in the general formulae (2) and (3) is an alkylene group having a carbon number of 2-10 or phenylene group. 
   
   
       6 . A rubber composition according to  claim 1 , which further contains 0.03-1 part by mass as a cobalt amount of an organic acid cobalt salt based on 100 parts by mass of the rubber component. 
   
   
       7 . A rubber composition according to  claim 1 , wherein the rubber component is at least one of natural rubber and polyisoprene rubber. 
   
   
       8 . A rubber composition according to  claim 1 , wherein the rubber component comprises not lower than 50 mass % of natural rubber and the remainder being a synthetic rubber. 
   
   
       9 . An adhesion improver comprising the compound represented by the formula (2). 
   
   
       10 . An adhesion improver comprising a composition containing 60-100 wt % of the compound represented by the general formula (2), 0-20 wt % of a compound represented by the general formula (3) in which n is 2, 0-10 wt % of a compound represented by the general formula (3) in which n is 3 and 0-10 wt % of a compound represented by the following formula (3) in which n is 4-6. 
   
   
       11 . A pneumatic tire comprising a carcass comprised of at least one carcass ply and a belt disposed on the carcass outward in a radial direction of the tire and comprised of at least one belt layer, wherein at least one of the carcass and the belt includes a layer composed of steel cords covered with a coating rubber, characterized in that a rubber composition as claimed in  claim 1  is used as the coating rubber covering the steel cords in at least one of the carcass and the belt.