Method for shaping a tubular film by liquid coagulation
Abstract
Abstract A TUBULAR FILM OF THERMOPLASTIC POLYMER HAVING ANY DESIRED DIAMETER IS SHAPED BY EXTRUDING IT DOWNWARDS IN A TUBULAR FORM AN ANNULAR DIE, WHILE APPLING GAS PRESSURE IN THE INSIDE OF THE TUBULAR FILM, BEFORE PASSING THE EXTRUDED FILM, SO AS TO EFFECT COMPLETE CONGULATION, THROUGH THE INSIDE OF A CYLINDRICAL NET PROVIDED IN CONTACT WITH A COAGULATION LIQUID WHICH IS SUPPLIED FROM THE TOP OF THE NET AND FLOWING DOWNWARDS ALONG THE SURFACE OF THE NET AND BY WITHDRAWING THE COAGULATED FILM FROM THE LOWER PART OF THE NET. BY ADJUSTING THE TENSION OF THE CYLINDRICAL NET, THE TUBULAR FILM IS ALWAYS IN LIGHT CONTACT WITH A TURBULENT STREAM OF THE COAGULATING LIQUID WITHOUT CHANNELLING OF THE STREAM, AND THE TUBULAR FILM OF ANY DESIRED DIAMETER AND THICKNESS CAN BE READILY PREPARED IN THE SAME APPARATUS.
Inventors
- 👤 Masahide Yazawa
Bibliographic Details
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