| abstract |
The invention relates to benzyl ether-type phenolic resins with reduced formaldehyde content, containing at least one formaldehyde scavenger in the form of a beta-dicarbonyl compound, and also an alpha-carbonyl-carboxyl compound, particularly glyoxylic acid, binders based on these phenolic resins, and isocyanate compounds comprising at least two isocyanate groups for use in a phenolic resin polyurethane cold-box process (PUCB process) and/or a phenolic resin polyurethane no-bake process (PUNB process). The invention also relates to moulding material blends containing said binder, and a method for producing cores, moulds or feeders. |