Foundry binder of epoxy resin, acrylated polyisocyanate and acrylic

A cold-box process for preparing a foundry shape comprising:

• A. preparing a foundry mix comprising:
• (1) a major amount of foundry aggregate;
• and
• (2) an effective bonding amount of the foundry binder system comprising:
• (a) from 5 to 80 weight percent of an epoxy resin;
• (b) from 15 to 80 weight percent of an acrylated organic polyisocyanate;
• (c) from 5 to 75 weight percent of a reactive unsaturated acrylic monomer, polymer, or mixtures thereof;
• and
• (d) an effective amount of an oxidizing agent comprising a hydroperoxide,
• where (a), (b), (c), and (d) are separate components or mixed with another of said components, provided (b) or (c) is not mixed with (d), and where said weight percents are based upon the total weight of the (a), (b), (c), and (d);
• B. introducing the foundry mix obtained from step (a) into a pattern;
• C. hardening the foundry mix in the pattern to become self-supporting;
• and
• D. curing with a gaseous amine, thereby obtaining a hard, solid, cured foundry shape.