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:
Sep. 19, 1989
Filed:
Mar. 06, 1989
Robert E Downing, Toledo, OH (US);
Farley, Inc., Chicago, IL (US);
Abstract
The coatings are for an expendable sand core for die casting dies, which sand core has spaces between its contacting sand grains at least partially filled with resin binder. The first, base, hard, or refractory coating for this core is applied from an aqueous suspension comprising a finely ground refractory of fused silica, a refractory binder, and at least two different compounds selected from the groups of compounds or additives consisting of: (1) a suspension agent, (2) a dispersant, (3) a wetting agent, and (4) an anti-skinning agent. The refractory in the first coating may also include a minor amount, i.e. less than 50%, of another refractory oxide. The amount of binder in the first coating is less than about 15% by weight of the total liquid suspension, and the amount of additives is less than about 1.5% and usually less than 1% by weight of the total liquid suspension. The second, top, soft, or release coating is an organic liquid suspension containing between about 5% and 60% by weight of the whole suspension of particles of a release material selected from the group consisting of anhydrous powdered aluminum, graphite, talc, titanium dioxide, and zircon, and less than about 10% by weight of the total suspension of a resinous binder, less than 15% of at least two additives or different compounds selected from the groups additives and compounds consisting of a suspension agent, a dispersant, and an anti-setting agent.