Friction material

Abstract

To provide a friction material with an excellent balance for both service brake and parking brake usage that satisfies the required performance for the service brake and improves the static coefficient of friction for the parking brake. The friction material comprising a fibrous base material, a friction modifier, and a binder, wherein said friction modifier comprises 2-20 volume % of cashew dust, 10-25 volume % of a rubber composition, and 2-5 volume % of a solid lubricant, a total volume of the cashew dust and the rubber composition is 30 volume % or less, and said friction modifier does not use graphite because it can cause the reduction of the coefficient of friction during the parking brake operation.

1 . A friction material comprising:
 a fibrous base material, a friction modifier, and   a binder, wherein   said friction modifier includes 5-20 volume % of cashew dust, 10-25 volume % of a rubber composition, and 2-5 volume % of a solid lubricant, a total volume of said cashew dust and said rubber composition is less than 30 volume %, and said friction modifier is without graphite.   
   
   
       2 . The friction material according to  claim 1 , wherein
 said cashew dust is manufactured using furfural as a curing agent.   
   
   
       3 . The friction material according to  claim 1 , wherein
 a part of said rubber composition is a vulcanized acrylic rubber powder, and said friction material includes at least 5 volume % or more of a vulcanized acrylic rubber powder as said rubber composition.   
   
   
       4 . The friction material according to  claim 2 , wherein
 a part of said rubber composition is a vulcanized acrylic rubber powder, and said friction material includes at least 5 volume % or more of a vulcanized acrylic rubber powder as said rubber composition.   
   
   
       5 . The friction material according to  claim 1 , wherein
 said solid lubricant is molybdenum disulfide.   
   
   
       6 . The friction material according to  claim 2 , wherein
 said solid lubricant is molybdenum disulfide.   
   
   
       7 . The friction material according to  claim 3 , wherein
 said solid lubricant is molybdenum disulfide.   
   
   
       8 . The friction material according to  claim 4 , wherein
 said solid lubricant is molybdenum disulfide.