Printhead assembly with multi-layered support structure

1. A printhead assembly comprising:

a printhead comprising a carrier which carries a integrated circuit (IC) configured to eject ink, the carrier defining a plurality of ink passages each in fluid communication with the IC; and

an elongate support which supports the printhead and defines a plurality of ink chambers each in fluid communication with a respective ink passage, the support comprising a core which defines the ink chambers and a multi-layered metal shell in which the core is received.

2. A printhead assembly as claimed in claim 1 , wherein the shell comprises a triplet of metal layers which together give the shell a coefficient of thermal expansion which is comparable to that of silicon material.

3. A printhead assembly as claimed in claim 2 , wherein one of the layers has a first co-efficient of thermal expansion and is located between a pair of layers each having a second co-efficient of thermal expansion.

4. A printhead assembly as claimed in claim 3 , wherein the first co-efficient of thermal expansion is greater than the second co-efficient of thermal expansion.

5. A printhead assembly as claimed in claim 4 , wherein the second co-efficient of thermal expansion is about 1.3×10−6 m/° C.

6. A printhead assembly as claimed in claim 4 , wherein the first co-efficient of thermal expansion exceeds 2.5×10−6 m/° C.

7. A printhead assembly as claimed in claim 1 , wherein the carrier is a micro molding.

8. A printhead assembly as claimed in claim 1 , wherein the core is molded from plastics material.