| abstract |
Described herein are polyurethane systems to be used as binders innadmixture with sand, or similar granular substances, for the production of mouldsnor cores for foundry use; in more detail, the invention relates to thenpolyisocyanate-based component that can be used in such binder compositions.nSaid component has the following percentage composition:n (a) a polyisocyanate in an amount of 50-95% by weight; (b) vegetable oil in an amount of 5-40% by weight; (c) an aprotic organic polar solvent in an amount of 2.5-30% by weight. |