| 摘要 |
PURPOSE:To produce a wet-type frictional material for clutch, usable in oil, by making a paper sheet from an aqueous dispersion containing cellulose and a filler, embossing the surface of the paper sheet with an embossing plate, pressing the sheet to form a layer having different porosity and impregnating and curing a thermosetting resin in the sheet. CONSTITUTION:In the cource of making a paper sheet from an aqueous dispersion 30 containing cellulose 20 and a filler 26, the embossing cylinder 32 is made to contact with the paper sheet 35 to form an embossed surface, and the surface of thesheet 35 is flattened by pressing with press rolls 37a, 37b to form the layer 16, 17 having different porosity. The paper sheet 35 having the layers with different porosity is dried with driers 39, 41, 42, and the obtained paper substrate 48 is cut with a cutter 49 to a prescribed size. The objective frictional material can be produced by impregnating and curing a thermoplastic resin 51 in the sheet after embossing the surface of the paper sheet. |
