Tire with chafer

Abstract

The present invention relates to a pneumatic tire having a pair of spaced apart bead components, a connecting carcass between said bead components, and a rubber chafer positioned around at least a portion of each of said bead components and intended for contacting a rigid rim of a wheel, wherein said chafer comprises a self lubricating rubber composition, the self lubricating rubber composition comprising at least one rubber and from 1 to 50 phr of at least one additive selected from alcohols of formula I, esters of formula II, or amides of formula III wherein R 1 and R 2 are independently selected from C 12 -C 36 alkyl, C 12 -C 36 alkenyl, or C 12 -C 36 alkadienyl.

1 . A pneumatic tire comprising a pair of spaced apart bead components, a connecting carcass between said bead components, and a rubber chafer positioned around at least a portion of each of said bead components and intended for contacting a rigid rim of a wheel, wherein said chafer comprises a self lubricating rubber composition, the self lubricating rubber composition comprising at least one rubber and from 1 to 50 phr of an amide of formula III  
     
       
         
         
             
             
         
       
     
     wherein R 1  and R 2  are independently selected from C 12 -C 36  alkyl, C 12 -C 36  alkenyl, or C 12 -C 36  alkadienyl.  
   
   
       2 . (canceled)  
   
   
       3 . (canceled)  
   
   
       4 . (canceled)  
   
   
       5 . (canceled)  
   
   
       6 . (canceled)  
   
   
       7 . The pneumatic tire of  claim 1  wherein the an amide is selected from caprylamide, laurylamide, palmitylamide, stearylamide, oleamide, and myristylamide.  
   
   
       8 . The pneumatic tire of  claim 1  wherein the composition further comprises 10 to 250 phr of a filler selected from carbon black and silica.  
   
   
       9 . The pneumatic tire of  claim 8  wherein said filler comprises silica.  
   
   
       10 . The pneumatic tire of  claim 8  wherein said filler comprises carbon black.  
   
   
       11 . The pneumatic tire of  claim 8  wherein the composition further comprises from 0.5 to 20 phr of a sulfur containing organosilicon compound of the formula:  
       Z-Alk—S n -Alk-Z  
     in which Z is selected from the group consisting of  
     
       
         
         
             
             
         
       
     
     where R 5  is an alkyl group of 1 to 4 carbon atoms, cyclohexyl or phenyl; R 6  is alkoxy of 1 to 8 carbon atoms, or cycloalkoxy of 5 to 8 carbon atoms; Alk is a divalent hydrocarbon of 1 to 18 carbon atoms and n is an integer of 2 to 8.  
   
   
       12 . The pneumatic tire of  claim 11  wherein said composition is thermomechanically mixed at a rubber temperature in a range of from 140° C. to 190° C. for a total mixing time of from 1 to 20 minutes.  
   
   
       13 . The pneumatic tire of  claim 1  wherein the rubber is selected from the group consisting of polybutadienes, styrene-butadiene rubbers, synthetic polyisoprenes, and natural polyisoprenes.  
   
   
       14 . The pneumatic tire of  claim 1  wherein the amide is present in an amount ranging from 2 to 25 phr.  
   
   
       15 . The pneumatic tire of  claim 1  wherein the tire is a heavy tire having a tread with a tread cross section of at least 4 centimeters thick.  
   
   
       16 . (canceled)  
   
   
       17 . (canceled)  
   
   
       18 . The pneumatic tire of  claim 8  wherein the tire is a heavy tire having a tread with a tread cross section of at least 4 centimeters thick.  
   
   
       19 . (canceled)  
   
   
       20 . (canceled)  
   
   
       21 . A pneumatic tire comprising a pair of spaced apart bead components, a connecting carcass between said bead components, and a rubber chafer positioned around at least a portion of each of said bead components and intended for contacting a rigid rim of a wheel, wherein said chafer comprises a self lubricating rubber composition, the self lubricating rubber composition comprising at least one rubber and from 2 to 5 phr of an amide selected from the group consisting of stearamide and oleamide, wherein the rubber composition has a coefficient of friction ranging from 1.35 to 2.61 as measured by ASTM D-1894, and wherein the tire is a heavy tire having a tread with a tread cross section of at least 4 centimeters thick.  
   
   
       22 . The pneumatic tire of  claim 21 , wherein the amide is stearamide and the rubber composition has a coefficient of friction ranging from 1.58 to 2.61 as measured by ASTM D-1894.  
   
   
       23 . The pneumatic tire of  claim 21 , wherein the amide is oleamide and the rubber composition has a coefficient of friction ranging from 1.35 to 1.9 as measured by ASTM D-1894.