| abstract |
Prodn. of a heat-cured, filled, modified MF resin compsn. (I) with good flow properties comprises plasticising a mixt. of 20-70 wt.% MF resin, 20-79 wt.% mineral and/or fibre filler (ground to 0.001-0.1 mm), 0.1-15 wt.% glycols and urea and/or triazine derivs., and opt. dicyandiamide, by roll-milling for 1-30 mins. at 60-140 deg.C. Fillers are quartz powder, glass fibre and/or cellulose, amt. of MF resin is 30-60 wt.%, pref. glycol is ethylene glycol, and the mixt. is roll-milled at 80-110 deg.C. USE/ADVANTAGE - (I) is useful as a mould-cleaning compsn. which effectively removes residues of polymers and additives (lubricants, etc.), with minimal evolution of formaldehyde, from moulds used, e.g. for the prodn. of electronic components sealed with epoxy resin. |