bearing having a structure shown in fig1 in the production process of the plain bearing at first metal powder 120 mesh or less made from cu and 10 weight sn is scattered on a back metal 1 so as to attain a thickness of 0 3 mm the back metal 1 is made of a steel sheet plated with copper and has a thickness of 1 2 mm thereafter the metal powder is heated at a temperature of 750 to 900 u00b0 c for 10 to 30 minutes for sintering so that a porous metal layer 2 made from cu sn is formed on the back metal 1 after the sintering the metal layer 2 is impregnated and coated with one of resins of samples 1 to 7 and comparison samples 1 to 4 shown in table 1 the base resin of which is ptfe and thereafter cured at 350 to 400 u00b0 c and subjected to rolling so as to form a resin layer 3 whereby a composite plate having a thickness of 1 5 mm is obtained the metal powder used in the resin layer 3 is bismuth particles having an average particle size of 15 u03bcm moreover the metal powder used in sample 6 is bismuth alloy particles including 10 weight silver and the metal powder used in sample 7 is bismuth alloy particles including 10 weight tin the composite plate is cut into a predetermined size and then formed into a cylindrical shape having an inner diameter of 20 mm and a width of 20 mm so as to form a test sample which comprises the back metal 1 the porous metal layer 2 sintered on the back metal 1 and the resin layer 3 provided on the inner.