Resin binders for chipboard - of phenolic or urea type contg alkaline earth halides

摘要

The binder compsns. contain, in addition to phenol or urea resin, hydrophobising agent, retarder (e.g. NH3) and water, an alkali(ne earth) halides (esp. NaCl) in aq. soln. P ref. compsns. contain 60 - 75% phenol or urea resin, 2.9 - 3.6% paraffin emulsion, 23 - 29% water, 1.3 - 1.7% NH3 add 2.1 - 2.4 (esp. 2.25%) halide, esp. NaCl. The binders are suitable for making chip- or fibre-board sheet, esp. the outer layers of laminates. A denser, more solid outer surface is obtd. after compacting under heat and pressure and the need to grind off the loose surface layer is avoided.