Bag for powder, has bag wall that is impermeable to dust and valve that allows gas to escape

摘要

The plastic bag wall is impermeable to dust. A pressure compensation valve (106) allows gas to escape from within the bag. A nonwoven fiber material (107) is in front of the escape valve (106), for the gas to pass through before it reaches the valve (106). Sealed bag (100) for holding powder, allows the contents to release gas when the bag is closed and sealed. The bag wall comprises a plastic film that is impermeable to dust. A pressure compensation valve (106) allows gas to escape from within the bag. A nonwoven fiber material (107) is in front of the escape valve (106), for the gas to pass through before it reaches the valve (106) to escape into the atmosphere, preferably using Tyvek (RTM) or Tyvek 1073D (RTM).