| 摘要 |
1,182,812. Laminates; forms of wood. M. EBNOTHER. 21 March, 1967 [25 March, 1966], No. 13080/67. Headings B5L and B5N. [Also in Divisions B6 and E1] In a method of producing a bonded joint between two surfaces, before the joint is closed the first surface is coated with an aqueous solution or dispersion of an adhesive which bonds by penetration of water or water-borne adhesive, whilst the second surface is coated with a substantially anhydrous adhesive coating which is adapted to absorb water from the aqueous adhesive on the first surface. Plastic laminate surfaces may be joined to chipboard; P.V.C. floor coverings may be laid; small plywood sheets may be laid on concrete floors, and wood fibre-panels may be joined to a wooden slat framework. The aqueous adhesive may be applied as a dispersion or solution and may comprise polyvinyl chloride, polyacrylic acid, water soluble copolymers, or aqueous urea-formaldehyde pre-condensates. The anhydrous coating may comprise polyvinyl alcohol, cellulose derivatives, polyacrylic acid, co-polymers of maleic anhydride and styrene or ethylene, polyvinyl pyrrolidone or co-polymers of vinyl pyrrolidone with vinyl acetate, or gluten and casein glues. Substances may be added to the aqueous adhesive which react with the anhydrous coating, e.g. calcium hydroxide for reaction with polyacrylic acid and boric acid or formaldehyde for reaction with polyvinyl alcohol. Quantitative examples are given. |
