GB1270110A - Improvements in or relating to pressing processes - Google Patents

Abstract

1,270,110. Diaphragm presses; laminating press. IMPERIAL CHEMICAL INDUSTRIES Ltd. 22 July, 1969 [5 Aug., 1968], No. 37304/68. Headings B5A, B5F and B5N. A resilient pressure applying and heating cushion plate for use in a laminating, moulding, or the like press comprises a flexible metal sheet sealed about its periphery to a backing plate, hot vapour being introduced into the interior of the cushion plate during pressing via an inlet and an outlet, the pressure of the vapour being such that it condenses within the plate during pressing. In one embodiment, in which the plate is located as a separate entity between the platens of a press along with the material to be worked, the plate consists of a pair of steel or copper sheets 21 welded to each other and provided with an inlet 22 and an outlet 23 located below the level of the inlet so that condensed vapour may be removed. In a second embodiment, in which the cushion plate forms the press plate itself, a steel sheet 25 is welded to a press plate 24 having an inlet 26 and an outlet 27 and a sloping surface 28, the surface facilitating drainage of any condensed liquid. In a third embodiment (see Fig. 5, not shown) the outlet and inlet, instead of being located in the press plate are located in the steel sheet. Where the plate is to be used as an upper platen, the surface of the press plate need not be inclined and drainage is facilitated by locating the outlet adjacent the surface of the sheet. Alternatively drainage may be effected by using the plates on the slant. The press plates may be used in the lamination of plywood, blockboard, plastics sheets such as P.V.C., or resin impregnated layers.