| 摘要 |
892,366. Laminates. AKERLUND & RAUSING A.B. March 21, 1960 [March 31, 1959], No. 9961/60. Class 140. A deep drawn laminate article, such as disposable service ware comprises a body formed of at least three layers of comparatively thin and easily worked cardboard material, laminated by deep-drawing under heat and pressure, the outer surface of one outer body layer being preformed with a coating or layer of material of limited extensibility resistant to penetration of moisture, fats and the like. The cardboard body layers may be laminated together by means of a thermosetting binding agent, the intermediate body layer or layers being impregnated with this agent. Suitable agents are water-glass or urea resin. As shown, Fig. 1 illustrates a service plate according to the invention having a central depression 1, with reinforcing bead 3 and embossing lines 4 and 5 to strengthen the structure. Fig. 2 shows a sectional view along line II-II in Fig. 1. Fig. 3 shows apparatus for making the plate, and Figs. 4 and 5 show the mandrel and drawing die of the deep drawing head. The plate comprises 4 layers, 6, 7, 8 and 9 (Fig. 2). Layer 6 forms the upper surface of the plate and consists of a film of extensible material, e.g. polyethylene or aluminium foil, resistant to penetration of moisture, oil and fat. Layers 7, 8 and 9 consist of cardboard. Layer 8 may be completely impregnated with the binding agent prior to lamination. Film 6 may be applied to layer 7 by extrusion or calendering laminating. Fig. 3 shows webs 11 and 12 corresponding to body layers 8 and 9, and web 10 corresponding to body layer 7 and film 6 prelaminated together, drawn from rolls 14, 15 and 13. Web 11 passes over rollers 16, 17 and 20, through liquid binder 18 in bath 19, past doctor blades 30, 31 and 32 and into the nip between rolls 21 and 22. Webs 10 and 12 are also drawn into the same nip and these combined with web 11 to form combined web 23 which passes over roller 33 and is then conveyed by intermittent feed mechanism 34 to the drawing head comprising movable mandrel 35 and stationary drawing die 36. Die 36, Fig. 5, comprises a flat steel plate 52 with a recess having a substantially cylindrical wall 53 forming a cutting edge 54. The hole accommodates steel matrix 55 whose bottom portion 56 is vertically movable in relation to the remainder of the matrix and is spring biased from beneath by spring 57 (Fig. 3). Mandrel 35 (Fig. 4) comprises steel plate 72 having projecting cutting and creasing rim 73. Patrix 63 is accommodated in hole 62 (Fig. 3) of plate 72 and comprises steel body 64 and an elastically yielding operative rubber facing 65. Upon closing the drawing head, cutting edges 61 and 54 punch out of the web 23 a piece corresponding to the service plate to be formed. The drawing head is maintained closed under heat and pressure until the laminating adhesive sets. |
