The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 19, 1982
Filed:
Oct. 29, 1980
David A Hutchings, Stow, OH (US);
Consolidated Foundries and Mfg. Corp., Chicago, IL (US);
Abstract
A process is disclosed for curing a sand-furan resin mixture used in foundry practice to form cores and molds by the use of sulfur dioxide gas without forming sulfuric acid. Curing occurs when the furan resin, that is one containing a predominant amount of a furan moiety, is intermixed with a minor amount of a diisopropylbenzene monohydroperoxide (DIPBMHP) or diisopropylbenzene dihydroperoxide (DIPBDHP), or a mixture thereof. In addition to reacting with gaseous sulfur dioxide without forming sulfuric acid, these specific alkaryl hydroperoxides of which the monohydroperoxides have at least one alkyl ring substituent, have the peculiar characteristic of curing the resin in such a way that the DIPBMHP or DIPBDHP moiety becomes chemically bound in the cured resin. The result is a cured core or mold having a novel composition and superior physical properties compared to prior art cores and molds made with furan resins, in which the reaction with sulfur dioxide produces sulfuric acid. Cores and molds made by the instant process perform as well as, or better than those made with hexamethylene tetramine initiated thermally polymerized phenol-formaldehyde novolac resins, when used under comparable shell casting conditions.