| 摘要 |
PURPOSE:To prevent the fray of fibers of a cut section and prevent the leakage of an electrolyte by melting the fibers of a non woven fabric made of polypropylene in a ring shape then cutting it to a predetermined size for use as a separator. CONSTITUTION:A part or all of fibers of a non woven fabric made of polypropylene are melted in a ring shape then cut to a predetermined size. Accordingly, the fibers are bound togeher instead of being merely entwined, thereby they are rarely frayed. As a means of melting, direct heating by use of a heated mold, et. or a means with ultrasonic waves can be considered. The width of the melted ring-shaped portion is desired to assure at least 0.5mm. or more for the width of the melted portion after cutting in view of strength. |
