US Patent 7530665 Printhead assembly with ink leakage containment walls

A printhead assembly includes a substrate defining a plurality of ink inlets. A plurality of nozzle assemblies is positioned on the substrate. Each nozzle assembly defines a nozzle chamber in fluid communication with a respective ink inlet and a nozzle opening from which ink can be ejected. A plurality of endless containment walls extend from the substrate and each surround a respective nozzle assembly so that leakage ink from the nozzle assemblies can be contained within the containment walls surrounding them.