Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
MICROPOROUS MEMBRANE, LITHIUM ION SECONDARY BATTERY, AND MICROPOROUS MEMBRANE PRODUCTION METHOD
Document Type and Number:
WIPO Patent Application WO/2018/043331
Kind Code:
A1
Abstract:
The present invention addresses the problem of minimizing the rate of film thickness change and the rate of air permeability resistance change after compression at 60℃ or 80℃. For stretching performed before solvent extraction, the present invention employs a method that involves stretching at least twice in at least two different axial directions, the stretching being performed to satisfy (i) and/or (ii). (i) Step (c) is a primary stretching step in which a sheet-shaped molded object is stretched at least once in each of a sheet transport direction (an MD direction) and a sheet width direction (a TD direction), and, in step (c), an MD stretching ratio and a TD stretching ratio satisfy (TD stretching ratio≥MD stretching ratio−2). (ii) The stretching temperature (T1) for first axis stretching that is performed first in step (c) and the maximum stretching temperature (T2) for second axis stretching that is performed second or later satisfy (T1−T2≥0).

Inventors:
ISHIHARA, Takeshi (Toray Industries Inc., 1190-13, Iguchi, Nasushiobara-sh, Tochigi 63, 〒3292763, JP)
Application Number:
JP2017/030538
Publication Date:
March 08, 2018
Filing Date:
August 25, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
TORAY INDUSTRIES, INC. (1-1 Nihonbashi-Muromachi 2-chome, Chuo-ku Tokyo, 66, 〒1038666, JP)
International Classes:
C08J9/26; C08J9/00; H01M2/16
Download PDF: