Phenol-formaldehyde resin for foundry applications

A no-bake foundry sand composition comprising:

• a. a foundry aggregate;
• b. between about 1 and about 5 parts by weight per 100 parts of aggregate of a phenolaldehyde resin made by:
• 1. heating phenol and an aldehyde in a mole ratio of aldehyde to phenol of between about 1.05 to 1 and about 1.5 to 1 in the presence of an alkaline catalyst until the free aldehyde content is less than one percent;
• 2. neutralizing the reaction product to a pH of about 5.5 to about 6.5 by adding an acid;
• and
• 3. dehydrating the resultant product to a viscosity of between about 1.5 and about 2.0 stokes and a water content of between about 10 and about 12 percent by weight, and
• c. between about 10 and about 60 parts by weight per 100 parts of resin of a curing catalyst.