Abstract: There is provided a method for producing a wet friction plate that can improve the retention property of lubricating oils in a fine groove formed by laser light. In a method for producing a wet friction plate (200), a friction material (210) is produced by sheet making processing in a first step. Thereafter, in a second step, a fine groove (211) is formed on the friction material (210). The friction material (210) is produced such that thermosetting resin therein is in a semi-cured state. The cross-sectional shape of the fine groove (211) is formed into a V shape by laser light. Subsequently, in a third step, the friction material (210) is disposed on a core metal (201) via an adhesive agent including thermosetting resin. Subsequently, in a fourth step, the friction material (210) is pressed while heated to crush the fine groove (211). In this manner, unevenness is formed on an intra-groove surface (212), and the thermosetting resin is completely cured.

Abstract: Provided are a method for manufacturing a wet friction plate, whereby efficiency of the work of forming a fine groove on a friction material can be improved, the wet friction plate, and a wet multiple-plate clutch device having the wet friction plate. In the method for manufacturing a wet friction plate 200, a core metal 201 and a friction material 210 are prepared, a resin layer 203 is formed on the core metal, the friction material is attached onto the resin layer, and a fine groove 211 is formed in the friction material. Specifically, irradiation of a laser beam L is started on an exposed portion 205 of the core metal. A laser head 301 is displaced in an annular shape while continuously emitting the laser beam. Thus, annular fine grooves 204 and 211 are formed in the exposed portion of the core metal and the friction material.

Abstract: Provided are a method for manufacturing a wet friction plate, whereby efficiency of the work of forming a fine groove on a friction material can be improved, the wet friction plate, and a wet multiple-plate clutch device having the wet friction plate. In the method for manufacturing a wet friction plate 200, a core metal 201 and a friction material 210 are prepared in a first step. Thereafter, a resin layer 203 is formed on the core metal 201 in a second step. The resin layer 203 is formed on each of entire two plate surfaces of the core metal 201. Subsequently, the friction material 210 is attached onto the resin layer 203 of the core metal 201 in a third step. Subsequently, a fine groove 211 is formed in the friction material 210 in a fourth step. Specifically, irradiation of a laser beam L is started on an exposed portion 205 of the core metal 201. A laser head 301 is displaced in an annular shape while continuously emitting the laser beam L.