MULTI LAYER BATTERY SEPARATOR WITH SUPERIOR PERMEABILITY

• Main Authors: PARK, SANG HYUN, KAN, TAE GYU, JO, BYOUNG CHEON, CHEONG, SANG BAE, JEON, MIN HO
• Format: Patent
• Language: English; Korean
• Published: 07.07.2015
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOSITIONS BASED THEREON; ELECTRICITY; GENERAL PROCESSES OF COMPOUNDING; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

The present invention may provide a multi-layered separation membrane and a method for manufacturing the same. The method includes the steps of: manufacturing a precursor film by co-extruding and molding a polypropylene based resin melted product having a melt index (2.16 kg, 230°C) of 0.3-5 g/10 min and a polypropylene based resin melted product having a melt index (2.16kg, 190°C) of 0.1-1.5 g/10 min so that the polypropylene based resin melted products can be alternately laminated; and treating the manufactured film with heat and then elongating the film. A melt index ratio (A/B) of the polypropylene based resin melted product (A) to the polypropylene based resin melted product (B) is 2-10. Therefore, inter-layer separation strength of the multi-layered separation membrane is increased; and, at the same time, the multi-layered separation membrane can have excellent permeability resulted from a high degree of orientation. 본 발명은 용융지수(2.16kg, 230℃)가 0.3 내지 5g/10분인 폴리프로필렌계 수지 용융물 및 용융지수(2.16kg, 190℃)가 0.1 내지 1.5g/10분인 폴리에틸렌계 수지 용융물을 서로 교번하여 적층되도록 공압출 및 성형 가공하여 전구체 필름을 제조하는 단계 및 상기 제조된 필름을 열처리 및 연신하는 단계를 포함하며, 상기 폴리프로필렌계 수지(A) 및 폴리에틸렌계 수지(B) 용융물의 용융지수 비(A/B)는 2 내지 10인 것을 포함하여 제조됨으로써 다층 분리막의 층간 박리강도를 향상시키고 동시에 높은 배향도에 따른 우수한 투과도를 발현할 수 있는 다층 분리막 및 이의 제조방법을 제공할 수 있다.