PURPOSE:To easy formation of oil films and to effectively suppress chattering sound by rolling a steel strip by using two pieces of rolls having straight projecting line parts and annular projecting line parts thereby forming grid-shaped grooves. CONSTITUTION:The steel strip 2 is rolled by 1st rolls 1 having the straight projecting line parts 10 by which the vertical groove groups 20 are formed thereon. The steel strip is then rolled by 2nd rolls 3 arrayed with the annular projecting line pars 30 to roll the horizontal groove groups 21, by which the grid-shaped grooves are formed. After such steel strip 2 is pinched by smooth rolls 4, the steel strip is subjected to blanking to form a grooved clutch plate. The clutch plate formed in the above-mentioned manner is not subjected to the conventional etching treatment; therefore, the surface parts has no protrusions and the noise (chattering sound) is effectively suppressed. Since the groove shape is tapered toward the deeper part of the plate, the oil flows readily on the surface and the oil films are easily formed.
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