| 摘要 |
The valve element for attachment to a flexible bag may include one or more flexible layers intended to extend over a hole disposed through a sidewall of the bag. In its normal condition, the layer or layers are in adjacent contact to each other or to the bag sidewall and thereby cover and seal the hole. During evacuation, the layer or layers displace to provide a collapsible and expandable channel that allows air to move from the hole to an exit point. To facilitate sealing of the valve element, a tacky surface is included in the valve element. The tacky surface can have a tackiness quality that normally holds the layers and/or sidewall together but that can be overcome during evacuation to expand the channel. |
