Polyethylene microporous film and process for producing the same
First Claim
Patent Images
1. A polyethylene microporous film having high strength and excellent heat resistance which has a crosslinked structure and has a porosity of 20-80%, a gel fraction of 1% or more and an average pore diameter determined by the permeation method of 0.001-0.1 μ
- m.
1 Assignment
0 Petitions
Accused Products
Abstract
A polyethylene microporous film excellent in mechanical strength, permeability and productivity and having a very high reliability such that the safety of a battery may be secured even under severe circumstances which film has a crosslinked structure and has a porosity of 20-80%, a gel fraction of 1% or more, and an average pore diameter determined by the permeation method of 0.001-0.1 μm, and a process for producing the polyethylene microporous film.
51 Citations
17 Claims
- 1. A polyethylene microporous film having high strength and excellent heat resistance which has a crosslinked structure and has a porosity of 20-80%, a gel fraction of 1% or more and an average pore diameter determined by the permeation method of 0.001-0.1 μ
- 7. A process for producing a polyethylene microporous film comprising the steps of preparing a hot solution consisting essentially of polyethylene and a plasticizer, cooling and solidifying the hot solution to form a sheet, stretching the sheet in at least a uniaxial direction to obtain an oriented film, and removing by extraction the plasticizer contained in the oriented film wherein at least one crosslinking treatment is applied to the sheet or film during any one of the process steps or after the process steps.
Specification