POROUS POLYIMIDE FILM, LITHIUM ION SECONDARY BATTERY SEPARATOR, LITHIUM ION SECONDARY BATTERY, AND ALL-SOLID BATTERY

• Main Authors: KAJIMA YASUNOBU, SUGAWARA HIROSHI, HIROSE EIICHI, YOSHIMURA KOSAKU
• Format: Patent
• Language: English; Japanese
• Published: 31.08.2020
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOSITIONS BASED THEREON; ELECTRICITY; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

To provide a porous polyimide film that has a good wettability and a high strength.SOLUTION: Provided is a porous polyimide film, in which the acid value of the porous polyimide film determined by acid-base titration is 7 mgKOH/g or more and 20 mgKOH/g or less, the total contained amount of metal groups consisting of alkali metal, alkaline earth metal and silicon excluding Li is 100 ppm or less for the porous polyimide film, and the moisture absorption percentage of the porous polyimide film is 0.5% or less.SELECTED DRAWING: None 【課題】濡れ性が良好で、高強度である多孔質ポリイミド膜を提供すること。【解決手段】酸塩基滴定により求めた多孔質ポリイミド膜の酸価が７ｍｇＫＯＨ／ｇ以上２０ｍｇＫＯＨ／ｇ以下、Ｌｉを除くアルカリ金属、アルカリ土類金属、およびケイ素からなる金属群の合計含有量が、多孔質ポリイミド膜に対して１００ｐｐｍ以下、多孔質ポリイミド膜の吸湿率が０．５％以下である多孔質ポリイミド膜である。【選択図】なし