Flexible printhead module incorporating staggered rows of ink ejection nozzles

1. A printhead module assembly comprising:

a printhead integrated circuit (IC) assembly having a plurality of ink ejection nozzles arranged to form staggered rows, and defining a plurality of ink channels for supplying ink to the ink ejection nozzles;

a flexible printed circuit board (PCB) electrically connected to supply both power and data to the IC assembly;

a support sheet defining a plurality of ink holes and to which the IC assembly is bonded so that the ink channels are aligned with the ink holes; and

a channel layer mounted to the support sheet adjacent to the IC assembly, the channel layer defining a plurality of slots aligned with respective air holes defined in the support sheet.

2. A printhead module assembly as claimed in claim 1 , wherein the support sheet defines a plurality of ink distribution channels extending from the ink holes.

3. A printhead module assembly as claimed in claim 2 , wherein another support sheet is mounted to the aforementioned support sheet and defines other ink holes which align with respective ones of the ink distribution channels.

4. A printhead module assembly as claimed in claim 3 , wherein the support sheets each further define a plurality of air holes which are aligned.

5. A printhead module assembly as claimed in claim 1 , wherein the slots are aligned with the IC assembly so that air from the air holes can be blown into the IC assembly via the slots.

6. A printhead module assembly as claimed in claim 5 , wherein a nozzle guard covers the nozzles and defines a plurality of air holes through which the blown air can exit the IC assembly.

7. A printhead module assembly as claimed in claim 1 , wherein the IC assembly is bonded by wires onto the PCB and the wires are encapsulated in an epoxy located between a dam wall mounted on the PCB and the IC assembly.