| 摘要 |
1,262,882. Rigid laminated panel. LONZA Ltd. 11 Feb., 1969 [10 Jan., 1969], No. 7444/69. Heading B5N. In the manufacture of a rigid laminated panel having a foamed plastics core between two non- extensible outer sheets, the flexibility of the core layer is increased by forming lattice patterns of grooves in each surface whilst maintaining a continuous central core layer parallel to the outer faces. Preferably, the lattices are such as to form lands of squares. The foam may be heat-treated before bonding to the facing sheets. Specified foamed plastics are closed-cell polyurethane, vinyl chloride polymers, cellulose acetate, polystyrene, phenolic resin, epoxy resin, polyester, acrylic resin or methacrylic resin. Specified facing materials are metal, plastics, reinforced plastics, wood, glass and ceramics. The bonding adhesive may be unsaturated polyester, epoxy resin, neoprene-based contact adhesive or copolymers of vinyl chloride with vinyl acetate (optionally including methyl methacrylate). |
