| 摘要 |
1,240,233. Granular aminoplast moulding compositions. H. RÍMMLER G.m.b.H. 29 April, 1969 [6 June, 1968], No. 21825/69. Heading C3R. Granular aminoplast moulding compositions are prepared by forming a dry homogeneous mixture of fillers, pigments and hardening agents in an intensive mixer, adding a lubricant to this mixture and transferring it when again homogeneous to a slowly rotating kneader, wherein it is impregnated with an aminoplast resin solution, and drying and grinding the product. The intensive mixer is one rotating at 500 r.p.m. or more, particularly with a propeller mixing element. The kneader may rotate at, e.g. 20-50 r.p.m. In Examples 5-7 mixtures of cellulose flour, with or without wood flour, TiO 2 , barytes, melamine and melamine phthalate are mixed intensively, Zu stearate is added and intensive mixing continued, then the mixture is kneaded with 50% aqueous UF, MF or melamine phenol formaldehyde resin under evaporation, and finally dried and ground. |
