WET TYPE FRICTION MATERIAL AND PRODUCING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a wet type friction material and producing method therefor capable of achieving a high frictional coefficientμand an improvedμ-V positive gradient with the usage of diatomaceous earth as an additive for improving the frictional coefficientμ. SOLUTION: When the diatomaceous earth having a diameter of 1 to 50μm is added as the additive so as to make paper for the wet type friction material, paste as a chemical showing delayed falling characteristic is added and papermaking is performed. The fine diatomaceous earth hardly sinks, a sinking speed gets slower by the delayed falling characteristic of the paste, and thereby paper is made on which surface the diatomaceous earth is concentrated. The wet type friction material is produced so that the surface becomes a friction surface. A friction examination is performed for thus produced wet type friction material in order to compare with a conventional wet type friction material whereon the diatomaceous earth is evenly dispersed. The friction examination is performed in a condition that a surface pressure is 980 kPa and an oil temperature is 80°. As a result, it is found out that this wet type friction material shows the enhanced friction coefficientμand the improvedμ-V positive gradient compared to the conventional wet type friction material. COPYRIGHT: (C)2003,JPO