Inkjet printhead assembly with an ink reservoir in a multi-layered shell

1. A printhead assembly that comprises

a carrier;

an integrated circuit (IC) configured to eject ink and mounted on the carrier, the carrier defining a plurality of ink passages each in fluid communication with the IC;

an elongate ink reservoir defining a recess in which the carrier can be received and a plurality of ink supply chambers which can each be located in fluid communication with a respective ink passage; and

a multi-layered shell in which the ink reservoir can be received.

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

3. A printhead assembly as claimed in claim 1 , wherein the ink reservoir is molded from a plastics material.

4. A printhead assembly as claimed in claim 1 , wherein the ink reservoir defines a neck portion and an enlarged head which is supported by the neck portion.

5. 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.

6. A printhead assembly as claimed in claim 5 , 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.

7. A printhead assembly as claimed in claim 6 , wherein the first co-efficient of thermal expansion is greater than the second co-efficient of thermal expansion.

8. A printhead assembly as claimed in claim 7 , wherein the second co-efficient of thermal expansion is about 1.3×10 −6 m/° C.

9. A printhead assembly as claimed in claim 7 , wherein the first co-efficient of thermal expansion exceeds 2.5×10 −6 m/° C.