An ink cartridge of the present invention has a storage element, in which plural pieces of specific information relating to an ink cartridge are stored at specific addresses that respectively occupy minimum bits required for storage. Namely the storage capacities required for storing the respective pieces of specific information are different from one another. For example, a piece of information on the year of manufacture is registered in a data length of 7 bits, a piece of information on the month of manufacture is registered in a data length of 4 bits, and a piece of information on the date of manufacture is registered in a data length of 5 bits. A piece of information on the time (hour) of manufacture is registered in a data length of 5 bits, and a piece of information on the time (minute) of manufacture is registered in a data length of 6 bits. A piece of information on the validity term of ink is registered in a data length of 6 bits, and a piece of information on the after-unsealed validity term is registered in a data length of 5 bits. This arrangement enables the specific information relating to the ink cartridge, for example, pieces of information on the manufacture of the ink cartridge and those on remaining quantities of the respective inks, to be stored efficiently into the storage element, while reducing the manufacturing cost of the ink cartridge.