Ink cartridge, ink jet recorder, and method of mounting ink cartridge

摘要

An ink supply port (4) is sealed with a seal material (7) made up of two layers of at least a physical protective layer and an airtight hold layer and formed with slits in the physical protective layer. When an ink cartridge (1) is mounted, a tip (42a) of an ink introduction member (42) breaks the seal material (7) sealing the ink supply port (4) along the slits made in the seal member, and air is released to the atmosphere without raising pressure of a space of packing. Then, the ink introduction member penetrates the packing.