| 摘要 |
996,399. Laminates and laminating. R. MOORMAN. Aug. 26, 1963 [Sept. 20, 1962], No. 33671/63. Drawings to Specification. Heading B5N. A sandwich-type or multi-layer low-density laminate is prepared by placing a first lamina, e.g. of impregnated fabric, on the surface of a mould, applying a mixture of hardenable resin with microparticulate aggregate dispersed therein as a coating layer upon the lamina surface, applying additional dry microparticulate aggregate to the surface of the mixture so that it is consolidated therewith and thereafter applying a second lamina, either before or after the consolidated mixture has hardened to form a rigid core having a density in the range 25-40 1b. per cu. ft. The second lamina may be the same as the first. The mixture may be applied as a pasty mass and spread over the surface with a serrated trowel to form a layer about # inch thick; it is then dusted with dry particles which may be lightly impacted with a flexible spatula to hasten their incorporation and consolidation. Thick layers may be built up by repeating the process but the final thickness should not exceed ¢ inch. The mixture may comprise a polyester resin containing phenolformaldehyde microballoons of about 5 to 20 microns dia., as aggregate, additional dry aggregate being added until no more can be consolidated with the resin. The size of particles should not exceed 500 microns. The second lamina may be pressed on to the core using a roller; further layers of core mixture, each followed by a lamina may be applied to build up a multi-layer laminate of any desired thickness. Alternative examples of resins are epoxy and phenolic and the fabric layer is preferably of glass fabric impregnated with hardenable resin. |
