Printhead incorporating rows of ink ejection nozzles

1. A printhead for an inkjet printer, the printhead comprising:

a wafer assembly defining rows of spaced apart ink supply channels; and

rows of ink ejection nozzle groups extending from the wafer assembly, each nozzle group including a pair of rows of ink ejection nozzles, each ink ejection nozzle including an ink ejection head from which an elongate actuator tail extends, all of the ink ejection heads of each group being in fluid communication with a respective ink supply channel, wherein

in each nozzle group, the actuator tails of one pair of rows of ink ejection nozzles extend in an opposite direction to the actuator tails of the other pair of rows of ink ejection nozzles, and

the actuator tails from adjacent rows of ink ejection nozzle groups are interleaved.

2. A printhead as claimed in claim 1 , wherein the rows of ink supply channels and rows of ink ejection nozzle groups are stepped rows.

3. A printhead as claimed in claim 1 , wherein each row of ink ejection nozzles is straight.

4. A printhead as claimed in claim 1 , in which electronic circuitry is positioned on the wafer assembly between the rows of ink ejection nozzle groups and circuit bond pads.

5. A printhead as claimed in claim 4 , wherein the electronic circuitry forms an elongate strip and the actuator tails extend obliquely relative to the strip.