| 摘要 |
<p>1462941 Sack KONINKLIJKE EMBALLAGE INDUSTRIE VAN LEER BV 23 Dec 1974 [2 Jan 1974] 00112/74 Heading B8K A sack comprises an inner envelope of porous material, e.g. extensible paper, and an outer plastics envelope made of a laminate of two mono-axially stretched films, the orientation direction of one film being at an angle to that of the other film and the laminate being perforated. The arrangement allows escape of air as the sack is filled. The inner envelope may be of crÛpe paper of, e.g. 75, 90, or 110 g./m.<SP>2</SP> and the plastics films may be of polyethylene with a laminate thickness of 75 to 120 micron. The perforations may be of 0À1 mm. diameter spaced 5 mm. in one direction and 10 mm. in the perpendicular direction. The envelopes may be tube lengths spot glued together at the top and bottom using, e.g. starch or polyvinyl acetate glue. The sack may have a filling valve.</p> |
