| abstract |
A heat resistant resin bonded grindstone is prepared by heating under pressure a molded composition comprising 20 to 50 vol. % of a polyimide resin powder, 50 to 70 vol. % of a metal powder, and 10 to 30 vol. % of a diamond powder, so that the diamond powder can be dispersed in and supported by a binder phase comprising the polyimide resin powder and the metal powder, in which the polyimide resin powder has been produced from a diamine compound comprising p-phenylenediamine and a mixture of 85 to 97 mol. % of 3,3′,4,4′-biphenyltetracarboxylic acid or its dianhydride and 15 to 3 mol. % of 2,3,3′,4′-biphenyltetracarboxylic acid or its dianhydride. |