Brother MFC9100C Service Manual page 23

(2) Ink cartridge
The equipment uses four ink cartridges (black, yellow, cyan, and magenta) of disposable type to
supply ink to the print head. As shown below, an ink cartridge contains an ink-impregnated
urethane foam. If ink-jet print operation or purging operation takes place, ink comes out of the
urethane foam and is supplied to the print head through the ink room, filters, and manifold.
For the ink cartridge sensors on the carriage PCB, refer to Section 2.3.
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