Wet-type paper friction member

Abstract

[Problems]To provide a wet paper friction member with both excellent friction property and high frictional coefficient. [Solution Means]A wet paper friction member is produced by impregnating a paper body with thermosetting resin, curing it by heating and then forming it by pressure. The paper body comprises cellulose pulp and a filler and further comprises aramid pulp the drainability of which is adjusted to 200-400 ml and aramid pulp the drainability of which is adjusted to 450-700 ml, respectively at 10-30 wt % of a total weight of the paper body, and said whole aramid pulp the drainability of which is adjusted comprises 30-50 wt % of a total weight of the paper body. Its surface roughness before and after pressure forming is adjusted so that the load length ratio Rmr (30%)≧55% as the load length ratio is defined by Rmr(C) (C: cutting level %). Thus, high frictional coefficient, heat resistance and mechanical strength are realized simultaneously.

1  A wet paper friction member which is produced by impregnating a paper body with thermosetting resin, curing it by heating and then forming it by pressure, 
 characterized in that said paper body comprises cellulose pulp and a filler and further comprises aramid pulp the drainability of which is adjusted to 200-400 ml and aramid pulp the drainability of which is adjusted to 450-700 ml, respectively at 10-30 wt % of a total weight of the paper body, and said whole aramid pulp the drainability of which is adjusted comprises 30-50 wt % of a total weight of the paper body:    
     
     
         2  A wet paper friction member as claimed in  claim 1 , wherein its surface roughness before and after pressure forming is such that the load length ratio Rmr (30%)≧55% as the load length ratio is defined by Rmr (C) (C: cutting level %).