Patent ID: 6040355
Filing Date: 2000-03-21
Classification: B22C

Abstract:
A process for producing a sand core which has been previously coated with resin, said resin being mixture of an isocyanate and a component selected from the group consisting of lignin, liquid protein, starches, epoxy ester, polyester polyols, polyether polyols, and epoxy resins, said process further utilizing heated air as a catalyst, said heated air having a temperature in the range of 180.degree. F. to 1000.degree. F., comprising the steps of:filling a mold with said sand which has been previously coated with a resin, said resin being a mixture of an isocyanate and a component selected from the group consisting of lignin, liquid protein, starches, epoxy ester, polyester polyols, polyether polyols, and epoxy resins; and,heating said sand core with air having a temperature in the range of 180.degree. F. to 1000.degree. F.