| abstract |
The invention relates to a phenolic resin composition for use in the polyurethane cold-box and/or no-bake process. The phenolic resin composition comprises an ortho-fused phenolic resol having etherified and/or free methylol groups in a total amount of 40 to 60 wt%, with respect to the total mass of the phenolic resin composition, free formaldehyde in an amount of less than 0.1 wt%, with respect to the total mass of the phenolic resin composition, one or more products of the reaction of formaldehyde with one or more C-H-acidic reactant compounds, and other constituents in a total amount of at least 38 wt%, wherein the amount of water in the phenolic resin composition is not greater than 1.0 wt%, in each case with respect to the total mass of the phenolic resin composition. The invention further relates to a two-component binder system for use in the polyurethane cold-box and/or no-bake process, to the use of a C-H-acidic compound as a formaldehyde scavenger for producing a phenolic resin composition for use in the polyurethane cold-box and/or no-bake process, to a process for producing a phenolic resin composition, to a process for producing a two-component binder system, to a process for producing a feeder, a foundry mold, or a foundry core from a mold material mixture, and finally to corresponding feeders, foundry molds, and foundry cores. |