Title:
HIGHLY POROUS SEPARATOR FOIL
Document Type and Number:
Japanese Patent JP2016196637
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a biaxially oriented single layer or multilayer porous foil with a Gurley value of less than 250 s, and a method for producing the foil by using a low transverse stretching velocity for the transverse orientation process.SOLUTION: The invention relates to a biaxially oriented, single layer or multilayer porous foil, the porosity of which is generated by transformation of β-crystalline polypropylene during stretching of the foil. The stretching of the foil is first performed in a longitudinal direction and then in a transverse direction. During longitudinal stretching, the neck-in ratio is 10% or less, the neck-in ratio being represented by the equation, neck-in ratio [%]=[(B0-B1)/B0]×100[%], where B0 is the width of the foil before the longitudinal stretching and B1 is the width of the foil after the longitudinal stretching. During transverse stretching, the foil is stretched by a transverse stretching velocity of 40%/sec or less. The foil comprises at least one porous layer containing at least one propylene polymer and β-nucleating agents, and has a Gurley value of less than 250 s. Preferably, the Gurley value of the foil is 10-200 Gurley.SELECTED DRAWING: None
Inventors:
DETLEF BUSCH
BERTRAM SCHMITZ
DOMINIC KLEIN
BERTRAM SCHMITZ
DOMINIC KLEIN
Application Number:
JP2016081076A
Publication Date:
November 24, 2016
Filing Date:
April 14, 2016
Export Citation:
Assignee:
TREOFAN GERMANY GMBH & CO KG
International Classes:
C08J9/00; H01G11/52; H01M50/406; H01M50/417; H01M50/449; H01M50/489; H01M50/491
Domestic Patent References:
| JP5955836B2 | 2016-07-20 |
Attorney, Agent or Firm:
Kurata Masatoshi
Nobuhisa Nogawa
Naoki Kono
Tadashi Inoue
Nobuhisa Nogawa
Naoki Kono
Tadashi Inoue