Patent ID: 6886928
Filing Date: 2005-05-03
Classification: B41J

Abstract:
1. An ink cartridge, comprising: a main case including an ink-holding portion for holding ink, the ink-holding portion having an indented surface portion and an open side, at least a portion of the indented surface portion having a semi-spherical shape with cross-sectional surface area that decreases with distance from the open side of the ink-holding portion, the main case further including an edge portion that encompasses the open side of the ink-holding portion, the edge portion having an inner edge that has one of a circular or ellipsoidal shape and that defines a boundary between the open side and the indented surface portion of the ink-holding portion; a flexible film that covers the open side of the ink-holding portion, the flexible film being attached to the edge portion so as to cover the open side of the ink-holding portion, the flexible film having a shape that substantially follows a shape of the indented surface portion when substantially no ink is held in the ink-holding portion; and a lid for engaging with the main case, the lid having a portion to encompass a bulge of the flexible film.