Patent ID: 7845780

Claim:
An ink cartridge having at least one ink container, which has an ink outlet with an ink outlet opening which extends from the inside to the outside, in the ink outlet opening a differential pressure valve is mounted which comprises a valve seat and a valve body which can move relative to the valve seat, the valve seat has a through valve opening which has a peripheral sealing surface, a spring means is attached between the movable valve body and the ink outlet, the valve body is pressed by the spring means with a predetermined closing force against the sealing surface of the valve seat from the outside to form a seal and can be moved against the closing force to the outside from the sealing surface, the valve seat being made deformable so that the sealing surface can be moved relative to the ink outlet opening, wherein the differential pressure valve opens when a pressure difference between an inside of the cartridge and an outside of the ink outlet opening exceeds a predefined pressure differential and wherein the spring means has a first permanent magnet which is mounted on the valve body, and a second permanent magnet which is attached securely in the ink outlet opening relative to the sealing surface and which is opposite the first permanent magnet with the same pole so that the repulsion force between the first and second permanent magnets acts as a closing force on the valve body.