Patent ID: 8523338

Claim:
An ink cartridge, comprising: a flat ink bag that has flexibility and has an ink supply port on one end thereof, the ink bag comprising two resin films welded together along opposed side edge portions thereof; an ink end detection plate adhered to the ink bag so that the ink end detection plate moves in accordance with a change of capacity of ink in the ink bag; a case that receives the ink bag while fixing one flat surface of the ink bag thereto so that ink can be supplied to outside from the ink supply port, the case having a recessed portion between a planar portion of the case and an inclined portion of the case; and regulation members which control deformation of the ink bag so that another flat surface of the ink bag can be deformed at a deformable position opposite the recessed portion of the case when the ink is consumed from the ink bag and the ink bag contracts, the regulation members comprising elastic film members adhered to the another surface at positions sandwiching the deformable position therebetween on the another surface of the ink bag, the regulation members extending to positions which cover the welded side edge portions of the ink bag in a lateral direction of the ink bag and being adhered the full width of the ink bag in the lateral direction thereof, one of the elastic film members being opposed to the planar portion of the case and another of the elastic film members being opposed to the inclined portion of the case.