| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas-permeable packing that is effective to prevent a liquid or solid, in which a chemical change takes place so that a gas is produced, from rupturing its container, that prevents degradation of the liquid impermeability and gas-permeability of a porous film even if the container turns over and its porous film gets wet, and that prevents a leakage of the contents. SOLUTION: The water-impermeable, gas permeable, and porous film 2 formed from polyolefin having a limiting viscosity of 3 dl/g or larger is affixed to at least one side of packing base material 4 formed from polyolefin having a passage 3 defined therein. Thus, the permeable packing can allow passage of gases through it but can prevent a leakage of liquid or solid contents. |
