| 摘要 |
A valve sack having a collapsible filling valve. A flattened tubular blank is formed by folding a second flap over a first flap to form a longitudinal seam. A valve is placed between the flaps transverse to the seam to provide communication with the interior of the sack, and is preferably located near one end of the sack. The valve may be formed in a variety of configurations, including a reinforcing projecting strip.
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