Printhead assembly with symmetrical tri-layer outer shell laminate

1. A printhead assembly for an inkjet printer, said assembly comprising:

an outer shell of a hot rolled tri-layer laminate of two different metals;

a core element within the shell, the core element defining four separate ink reservoirs;

a printhead constructed using MEMS techniques to provide ink nozzles, chambers and actuators; and

a micro molding for distributing ink from the ink reservoirs to the printhead,

wherein the tri-layer shell is configured such that the effective coefficient of thermal expansion of the shell as a whole is substantially equal to that of silicon, and

the outer layers of the tri-layer laminate are symmetrically disposed around a central layer thereof.

2. The printhead assembly of claim 1 , wherein the outer layers of the tri-layer laminate are made of Invar® metal having a coefficient of thermal expansion of 1.3×10 −6 m/° C.

3. The printhead assembly of claim 2 , wherein the central layer of the tri-layer laminate has a coefficient of thermal expansion of greater than 2.5×10 −6 m/° C.

4. The printhead assembly of claim 1 , wherein the ink reservoirs collectively lead to the micro molding which is configured to operatively receive the printhead.

5. The printhead assembly of claim 1 , wherein the core element is a plastic extrusion.

6. The printhead assembly of claim 5 , wherein the core element includes extruded membranes internally subdividing the element into the reservoirs.

7. The printhead assembly of claim 1 , having a support member for attaching the printhead assembly to the printer.