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:
Mar. 28, 1978
Filed:
Feb. 23, 1976
Applicant:
Inventors:
David R Lankard, Columbus, OH (US);
Walter A Hedden, Worthington, OH (US);
Assignee:
PMCMA Research Group, Dayton, OH (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B28B / ;
U.S. Cl.
CPC ...
106 383 ; 106 389 ; 106109 ; 106110 ; 106315 ; 106D / ;
Abstract
A fibrous talc-free plaster molding composition comprises by weight approximately 50-70% gypsum plaster, 5-20% fibrous wollastonite, 5-25% fine expanded perlite, and 0-40% of a filler selected from the group consisting of sand, fly ash, pyrophyllite and mixtures thereof. The composition of this invention has good dry blending properties, slurry characteristics, and wet and dry mold features, making it a suitable replacement for fibrous talc-containing molding compositions for low fusion metal casting molds.