| 摘要 |
Thermoplastics fibres laid out in a random fleece arrangement are sprayed with latex, thus fixing them in position. Heat and pressure are then applied to form cross seams made up from molten or fused fleece material. Polyamide, polypropylene or polyester are used as thermoplastics, preferably 2 g dry latex per m2 surface area. A calendar stage at 135-165 degrees C can be interposed between spraying and seaming. The seam rupture strength obtained should be 8 kg/cm, with surface weight of the sack fleece between 50 and 200 g/m2. the sack can "breathe" and is thus suitable for perishables.
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