| 摘要 |
1,274,544. Producing corrugated laminates by extrusion. MITSUBISHI KASEI KOGYO K.K., and S. AKAMATSU. 14 July, 1969 [18 July, 1968; 26 Aug., 1968; 17 Sept., 1968 (2)], No. 35270/69. Headings B5A and B5N. To produce laminated plastics sheet material having a corrugated layer, a plastic sheet 10 is delivered from an extruder 11 to the nip between corrugating rollers 12, 13 and a second plastics sheet 14 delivered from an extruder 15 is brought into contact with the corrugated sheet by means of a roller 16, adhesion between the sheets being due to residual plasticity in newlyextruded sheet 14. Subsequently as shown, a second extruded sheet 23 may be applied to the corrugated sheet in a manner similar to that of sheet 14. A multi-layered product may be produced by initially bringing together a number of corrugated sheets with the corrugations of adjacent sheets crossing one another and then applying flat sheets to opposite sides of the assembly. The materials of the sheets may differ and in this case particles of a substance such as calcium carbonate may be sprinkled on the flat sheet material to aid adhesion. Plastics specifically mentioned are polyethylene, polypropylene, polystyrene, P.V.C. and polyvinylidene chloride. The sheets may be foamed. In the apparatus, corrugating rollers 12, 13 are temperature controlled, the temperature of roller 13 being maintained above that of roller 12. Such temperature control in effect cools sheet 10; this cooling may be supplemented by a water spray while sheet 10 is on roller 13. Sheet 14 is cooled by roller 17. Sheet 23 is brought into contact with corrugated sheet 10 by passage through the nip of rollers 20, 21 the former being maintained at a higher temperature than the latter. To prevent distortion when sheet 23 contracts on cooling a band 22 which applies tension to sheet 14 and roller 20, rotating as shown, increase the distance between the corrugations at the point of application of sheet 23. This sheet is cooled by an air jet from nozzle 27 and sheet 14 is further cooled by contact with a cooler 26. In a modification, Fig. 2 (not shown), the peripheral length of roller 21 in contact with the laminate is effectively increased by the provision of a guide roller 28. The sheet material used may be of film thickness. |
