POLYOL COMPOSITION OF THE TWO-PART SYSTEM FOR FOAM GRINDSTONE, TWO-PART CURABLE COMPOSITION FOR FOAM GRINDSTONE, FOAM GRINDSTONE, AND PROCESS FOR PRODUCTION THEREOF

摘要

A polyol composition obtained by dissolving homogeneously a polyaminochlorophenylmethane mixture (A) consisting of 50 to 70 wt% of a specific binuclear polyaminochlorophenylmethane compound, 20 to 40 wt% of a specific trinuclear polyamino- chlorophenylmethane compound, and 5 to 10 wt% of a specific tetranuclear polyaminochlorophenylmethane compound in a polyol (B) at an (A)/(B) weight ratio of 30/70 to 60/40 is excellent in compatibility and solution stability and exhibits liquid properties, thus enabling the production of foam for grindstone by foam casting with a simple casting machine of two-solution mixing type. According to the invention, water serving as a blowing agent can be added to an MBOCA- containing polyol composition and the two-part curable composition for foam grindstone can be controlled at a temperature of the boiling point of water or below, which leads to no scattering of water in the foam casting step and thus enables the production of a foam grindstone having a uniform density distribution and excellent mechanical characteristics. Thus, the invention also provides a process for the production of excellent foam grindstone.