Ink-jet printing apparatus and ink cartridge therefor

The present invention relates to an ink cartridge detachably mounted on an ink jet printing apparatus for supplying ink to a printhead (5; 6) of the printing apparatus through an ink supply needle (6, 7), the ink cartridge comprising: a housing (4', 5') containing in therein having a first external wall and a second external wall intersecting said first external wall; an ink supply port (44, 54) formed on said first wall of said housing for receiving the ink supply needle and directing ink in said housing to the printhead; a circuit board (31) mounted on said second wall of said housing; and a semiconductor storage device (61) disposed on said circuit board for storing information about the ink carried by the ink cartridge; and a plurality of contact electrodes (60) arranged on said circuit board for electrically connecting said semiconductor storage device to the ink jet printing apparatus, said electrodes comprising at least one electrode (60-2) for contacting and grounding at least two contact forming members (29) of the printing apparatus when the ink cartridge is installed on the printing apparatus.