Patent GB-1006294-A (GB)
Title: Prefabricated panel or sheet for use in building or for other purposes
Inventor: BUSBY WILLIAM
IPC: B29C67/24
Filed: 1962-07-13
Abstract: 1,006,294. Laminates and laminating. SHAWELL SAND & GRAVEL COMPANY Ltd. July 10, 1963 [July 13, 1962], No. 26959/ 62. Heading B5N. [Also in Division B2] A rigid panel or sheet comprises at least one layer 2, 5, 6, of hard particles 3, e.g. chippings of stone or marble, pebbles, or chippings or granules of glass or of a synthetic plastics material, embedded in a bonding mass of clear transparent or translucent synthetic resin, and at least one backing layer 4 of the resin reinforced by a fibrous material embedded therein and bonded to the mass of resin in which the particles are embedded. The fibrous material may be contained in the resin in which the particles are embedded. The panel or sheet may have a surface layer 1 of transparent synthetic resin. The fibrous material may be of glass fibre or any suitable natural or synthetic fibrous material, e.g. sisal, flax or nylon. At least part of the resin may be coloured. The particles may protrude through the surface that is remote from the backing layer or layers of the layer of resin in which the particles are embedded. The panel or sheet may be made (1) by arranging the particles in at least one layer, forming a bonding mass of the clear transparent or translucent synthetic resin around and between the particles, -forming on the layer or layers at least one backing layer of resin reinforced by fibrous material embedded therein, and allowing the resin in all the layers to cure and become bonded together; (2) by forming a first layer of synthetic resin containing fibrous reinforcing material, this being the backing layer, and a second layer of the clear transparent or translucent resin on the first layer, pressing a layer of the particles into the resin of the second layer such that the upper surfaces thereof protrude from the upper surface of the second layer, and allowing the resin of all layers to cure and become bonded together; and (3) feeding a bottom web 11 of thin sheet material, e.g. transparent cellulose film, on to a flat surface of a conveyer 10, feeding a first layer 13 of clear transparent or translucent synthetic resin on to the sheet material, feeding the particles, resin and fibrous material in at least one second layer 15 on the first layer, effecting vibration of the conveyer (at 17), feeding a final layer 18 of the resin on to the second layer or layers, feeding a top web 20 of thin sheet material, e.g. transparent cellulose film, on to the final layer of resin, compressing all the layers between the bottom and top webs of sheet material, e.g. by roller 22 to form a continuous laminated sheet, passing the laminated sheet on the conveyer to a curing region, cutting panels of desired length from the laminated sheet and finally stripping the top and bottom sheet material from the panel. The resin employed may be an unsaturated polyester resin, e.g. orthophthalic polyester resin or epoxy resin which has been mixed with a catalyst, e.g. methyl ethyl ketone peroxide, and may also contain an accelerator to effect atmospheric curing.