| 摘要 |
<p>An improved high speed cast process for fusing fasteners, with strips of film at their base, to separately extruded film or sheet stock for making containers with integral closure means. The process makes available multiple sets of male and female fastener elements, with variable spacing, in a single extrusion operation. The apparatus includes a forming die (16) for extruding the film (46) through a film forming slot (56) in the die, a die block (22) positioned adjacent to the forming die (16) for extruding a fastening element (48) through a channel (44) thereof at a predetermined angle with respect to the extruded film (46) for joining the fastening element (48) to the film (46), a chill roll (28) for cooling the combined film and fastening element, the chill roll being positioned with respect to the film forming die (16) and the die plate (52) to provide a predetermined distance (h) between a horizontal line extending tangentially from an outer circumferential surface of the chill roll (28) and a die lip (62) on the film forming die (16) and a predetermined distance (d) between a vertical line extending from the die lip (62) on the film forming die (16) and a predetermined distance (d) between a vertical line extending from the die lip (62) to said outer circumferential and tangential surface of the chill roll (28). The apparatus is configured so that adhesion between the fastener elements and the film or sheet occurs very close to the die lips before significant cooling of the extrudate occurs. Containers with improved profiles are obtained because the base permits the profiles to remain relatively rigid during closing and opening.</p> |
