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:
Feb. 23, 1982
Filed:
Oct. 16, 1980
Applicant:
Inventor:
Horacio E Bergna, Wilmington, DE (US);
Assignee:
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B28B / ;
U.S. Cl.
CPC ...
106 3835 ; 106 / ; 106 388 ; 106 81 ; 106 83 ; 1061 / ; 260 / ; 260 / ; 260 / ; 260 4213 ;
Abstract
Binder solution for preparing sand cores of initial high strength but with essentially no strength after casting metals above 700.degree. C., said binder solution comprising an aqueous solution of sodium, potassium or lithium silicate having an overall molar ratio of SiO.sub.2 /alkali metal oxide from 3.5:1 to 10:1, and containing sufficient amorphous silica so that the fraction of the total silica in the binder solution which is present as amorphous silica is from 2 to 75%, the amorphous silica having a particle size in the range from about 2 nanometers to 500 nanometers.