Shell mold composition and method of making same

Claim 1

COATED SAND COMPOSITION FOR THE FABRICATION OF SHELL MOLDS AND THE LIKE WHICH CONSISTS ESSENTIALLY OF AT LEAST ABOUT 86 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE COMPOSITION, OF SAND; BETWEEN ABOUT 1 AND 10 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE COMPOSITION, OF AN AQUEOUS PHENOLIC LIQUID RESIN, SAID PHENOLIC LIQUID RESIN BEING AN AQUEOUS PHENOL-FORMALDEHYDE LIQUID RESIN THAT HAS A GREATER THAN 1:1 MOLE RATIO OF FORMALDEHYDE TO PHENOL, RESPECTIVELY, A SOLIDS CONTENT IN THE AQUEOUS VEHICLE OF AT LEAST 50 PERCENT BY WEIGHT, A PH BETWEEN 5 AND 9 AND A VISCOSITY AT 77*F. BETWEEN ABOUT 100 AND 1000 CENTIPOISES; BETWEEN ABOUT 0.5 AND 3.0 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE COMPOSITION, OF A FLOW-ASSISTING RESIN THAT IS SELECTED FROM THE GROUP CONSISTING OF A "NOVOLAK TYPE" PHENOL-FORMALDEHYDE RESINOUS CONDENSATION PRODUCT, SAID NOVOLAK RESIN BEING A PHENOLFORMALDEHYDE CONDENSATION PRODUCT THAT CONTAINS FROM 3 TO 10 PHENOLIC UNITS IN ITS MOLECULE AND HAS A LESS THAN 1:1 MOLE RATIO OF ALDEHYDE TO PHENOL, RESPECTIVELY, AND A THERMOPLASTIC "LIGNIN TYPE" RESIN DERIVED FROM WOOD, SAID LIGNIN TYPE RESIN BEING A THERMOPLASTIC MATERIAL THAT IS DERIVED FROM WOOD AND CONTAINS METHOXYL AND HYDROXYL GROUPS IN ITS MOLECULE; BETWEEN ABOUT 0.5 AND 2.0 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE COMPOSITION, OF A CATALYST SELECTED FROM THE GROUP CONSISTING OF POWDERED MAGNESIUM OXIDE HAVING A SETTING TIME OF LESS THAN ABOUT 6 HOURS, AQUEOUS SLURRIED MAGNESIUM OXYCHLORIDE, AQUEOUS SLURRIED MAGNESIUM OXYSULFATE AND MIXTURES THEREOF.