| abstract |
720,922. Making sheet material from thermoplastic material by rolling. UNION CARBIDE & CARBON CORPORATION. April 20, 1953 [May 3, 1952], No. 10822/53. Class 87 (2) Marbled sheet is made by feeding hot granular thermoplastic material, e.g. containing a copolymer of vinvl acetate and vinyl chloride at a temperature not less than 110‹C. to the first bite of a calender (Fig. 1) together with cold coloured slivers which are arranged with their axes parallel to the rolls, after which the sheet forms into folds at the second bite which exerts lateral pressure on the colour streaks to give a marble-like effect as in Fig. 5. The strip is cooled by passing over the bottom roller. |