| 摘要 |
A narrow tape of high strength and low elongation to break for use for example as a tear tape or packaging tape is formed by extruding continuously from preferably polypropylene a strip of tape and applying to the strip an adhesive layer on one surface. After extrusion and after application of the adhesive strip, the tape is drawn longitudinally by an amount sufficient to substantially fully orient the tape in the longitudinal direction to provide the required low elongation to break and high strength. The tape is extruded in a width so that when drawn the width of the drawn tape is equal to the required width of the finished tape. Instead of slitting the tape from a wide web, therefore, the tape is extruded directly in tape width without slitting or trimming thus obviating any waste. In addition the longitudinal drawing of the tape reduces the thickness of the adhesive to a thickness just sufficient to provide the required level of pressure sensitive adhesion without use of excess materials.
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