Shrink films produced from PVC are ideal display packaging materials. Their excellent mechanical strength and tear resistance not only offer good protection, but also make tight wrapping over virtually all types of shapes possible. High gloss and trasparency greatly contribute to enhance product attractiveness. They can be extruded easily with minimum and maximum MD/TD Shrink ratios of 10:50 and shrink at very low temperatures. Material waste during production is almost inexistent because the bubble can be adjusted to final film width requirements. PVC shrink films work excellently with all manual, semi-automatic, and high speed automatic shrink tunnels. Their main packaging applications based on specific built-in features during extrusion, are toys, perfume, video cassettes, computer supports, stationery, cosmetic and toilet articles, electronic accessories, and a multitude of other products.
PVC - SHRINK |
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Single screw extruder model | TR80 | TR100 |
Production output (kg/h) | 100 | 120 |
Maximum layflat width (mm) | 1200 | 1450 |
Film thickness (µ mm) | 15-40 | 15-40 |
N° centre folder reels | 2/4 | 2/4 |
Width centre folder reels (min/max) | 150-600 | 150-700 |
The melt is extruded through a circular die and istantly cooled by an air ring to obtain the primary tubular film. This tube is subsequently heated until it reaches a temperature at which the inflation of the secondary bubble is possible. Bi-axial orientation is obtained in both directions simultaneously by the air quantity and the differential speed ratio between the nip rollers before and after the ovens. The secondary bubble is cooled by air, laid flat and then goes into the rotating rewinding unit with two station placed back to back. The standard plant gives an output of 120 kg/h producing a lay flat width of 1450 mm and permits film gauges between 15-60 microns. The final product can either be edge trimmed and rewound as two reels of single film or, as is mainly demanded by the market, slit and rewound to obtain 4 reels of centre-folded film directly off the extrusion plant without additional handling.