Method for controlling the thickness of polymeric film structures
Abstract
Abstract A method is provided for manufacturing film structures of organic thermoplastic polymeric materials of improved thickness uniformity across the width thereof. Briefly, the method comprises measuring the thickness of a film structure at any location across the width thereof before stretching, measuring the thickness of said film structure at any location across the width thereof after stretching, computing the cumulative mass values of said film structure across the width thereof before and after stretching, and adjusting the thickness of said film structure at any point across the width thereof before stretching responsive to deviation from a preselected value in thickness of said film structure after stretching corresponding to the cumulative mass value of said film structure before and after stretching.
Inventors
- 👤 Frederick Lynn Knowles
Bibliographic Details
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