MANUFACTURE OF EMBOSSED THERMOPLASTIC RESIN SHEET

PURPOSE:To manufacture embossed thermoplastic resin sheet with high thickness accuracy and surface roughness accuracy at high speed with high production stability by a method wherein embossing is applied to the sheet, which is prepared by extruding molten thermoplastic resin into the form of sheet and, after being cooled, the surface of which is heated so as to make the surface temperature higher than the internal temperature and which is in dry state. CONSTITUTION:Molten thermoplastic resin is extruded in the form of. sheet 3 from an extrusion port 2, which is provided facing downwards, and immediately introduced vertically downwards in a water bath 4, the water temperature in which is controlled to be 25-45 deg.C so as to be cooled through guide rolls 5 and 6 by water-bathing. After that, the resultant sheet is led upwards so as to be fully cooled to its core part in the direction of the thickness in order to be sent in the form of sheet 7 to water absorbing rolls 8, 9 and 10 for removing and reducing water content. Further, the sheet 7 is sent to temperature controlling rolls 11-15, the temperature of which is controlled to be constant, so as to make the surface temperature of the sheet is higher than its internal temperature and, at the same time, bring the sheet in dry state in order to be turned into the state being suitable for embossing with embossing rolls 16 and 17. Thus, embossing with high thickness accuracy and surface roughness accuracy of the resin sheet is realized.