Shell molding composition containing thermosetting resin and method for making same

Claim 1

A FREE FLOWING BLOWABLE MOLD FORMING COMPOSITION CONSISTING ESSENTIALLY OF A MAJOR PROPORTION OF SAND, A MINOR PROPORTION BUT AT LEAST 1% OF A POWDERED THERMOSETTING PHENOL-FORMALDEHYDE RESIN, AND A LIQUID COATING AGENT ON THE SURFACE OF THE SAND PARTICLES CAUSING THE RESIN TO FORM A SUBSTANTIALLY UNIFORM COATING ABOUT EACH SAND PARTICLE, SAID COATING AGENT BEING AN ORGANIC ESTER OF AN ORGANIC ACID SELECTED FROM THE GROUP CONSISTING OF PHTHALIC ACID, SEBACIC ACID, BENZOIC ACID, MALEIC ACID, ADIPIC ACID, AND MIXTURES THEREOF, SAID COATING AGENT BEING A LIQUID AT A TEMPERATURE OF ABOUT 20*C, HAVING A BOILING POINT OF AT LEAST 100*C, AND BEING SUFFICIENTLY SOLUBLE IN SAID RESIN TO SOFTEN IT TO SUCH A DEGREE AS TO ENABLE IT TO FORM A UNIFORN COATING ABOUT TH E SAND PARTICLES AS A RESULT OF MIXING AND WITHOUT APPLICATION OF EXTERNAL HEAT, THE RATIO OF SAID COATING AGENT TO SAID RESIN BIENG IN THE RANGE OF 1:10 TO 4:10 BY WEIGHT.