| 摘要 |
Both walls of the plastics sleeve forming the valve in the cross bottom plastics bag or sack are folded over onto each other in the same direction at the end of the valve sleeve nearest the inside of the bag. The upper wall on the sleeve part not folded has a transverse slot spaced from the folding edge and sized to admit the nozzle of the filling machine. The slot is pref. a perforated line right across the sleeve to equal the largest nozzle used. |
