| abstract |
(57) [Summary] [PROBLEMS] In a technology for producing a microporous polyethylene membrane, Provided is a manufacturing method for improving permeable performance by adjusting porosity to a wide range by a simple process. SOLUTION: In the method for producing a microporous polyethylene membrane, a rate of change R represented by the following formula (1) is 0.80 to 1.0. It is stretched before extraction so that it becomes 20. R = P รท P O (1 ) ( wherein, P is the porosity after stretching, P O represents the porosity before stretching.) |