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:
Jul. 28, 1998
Filed:
Jun. 06, 1996
Kenneth R Kurple, Anchorville, MI (US);
Other;
Abstract
A process for making foundry cores and molds is disclosed as well as the core and molds which are produced as well as a sand binder. The binder is a resin which includes a lignin dissolved in a suitable solvent reacted and/or cured with an isocyanate material. The lignin used contains no more than 2% sodium ions. A polyether polyol may be added which has a functionality of greater than 3 and preferably at least 6. A tin catalyst is disclosed for use in the system which has a valence of +4 and one soluble in the system. A material is added to the system to give the mold or core a resistance to the water in core and mold washes. Suitable materials are propylene oxide derivatives of bis phenol A.