FABRICATION OF MINERAL SLABS WITH A PLASTICS SURFACES FINISH

摘要

1294320 Laminates INTERNATIONAL PATENT DEVELOPMENT CORP 25 Nov 1969 [26 Nov 1968] 57647/69 Heading B5N [Also in Division C3] Hard mineral fibre slabs with a plastics surface finish are produced by impregnating paper with an aqueous alcoholic solution containing a phenolformaldehyde resin, stearine, hexamethylenetetramine and a wetting agent and pressing it on to a web of resin impregnated mineral fibres. The solution with which the paper, which may be printed or unprinted, is impregnated may be prepared by dissolving in alcohol a phenolformaldehyde resin, and adding thereto an alcoholic solution of stearine and an aqueous solution of hexamethylenetetramine and a wetting agent, e.g. a condensation product of coconut oil fatty acids with diethanolamine. The impregnated paper may be dried at 80-110‹ C. before pressing. The mineral fibres used to make the web may be prepared by subjecting molten slag to a plurality of rollers having progressively increasing angular velocities, the fibres produced being driven by a flow of air from the fibre making equipment into a sedimentation chamber where they are impregnated with resin in fluid or powder form and deposited on to a moving continuous chain transporter with a negative pressure arranged underneath it so that even felting of the fibres is obtained. The web may be pre-dried to remove water from the aqueous solution of the resin and placed on a printed paper sheet impregnated with the phenolformaldehyde resin solution lying on a stainless steel sheet and if desired a second paper sheet impregnated with phenol-formaldehyde resin placed on top of the web with another stainless steel sheet mounted thereon. The slab may then be placed into a press where a pressure of 2-5 Kp./cm.2 and a temperature of 80-110‹ C. are applied.