Hydrophobic nozzle plate structures for micro-fluid ejection heads

1. A nozzle plate for a micro-fluid ejection head, the nozzle plate comprising a photoimageable hydrophobic polycyclic polyolefin layer derived from an epoxy functionalized polynorbornene attached to an ejection head structure.

2. The nozzle plate of claim 1 , wherein the hydrophobic layer has a thickness ranging from about 0.02 to about 50 microns.

3. The nozzle plate of claim 1 , the nozzle plate comprises a material selected from the group consisting of polyimide and a negative photoimageable polymer, and the hydrophobic layer is applied to the nozzle plate material.

4. The nozzle plate of claim 1 , wherein the nozzle plate consists essentially of the hydrophobic layer comprising polynorbornene and the nozzle plate is attached to a thick film layer on a substrate providing the ejection head structure.

5. The nozzle plate of claim 4 , wherein the thick film layer comprises a material derived from a hydrophilic functionalized polynorbornene.

6. The nozzle plate of claim 1 , wherein the hydrophobic layer has a glass transition temperature of greater than about 150° C.

7. The nozzle plate of claim 1 , wherein the hydrophobic layer has a number average molecular weight ranging from about 40,000 to about 80,000.

8. The nozzle plate of claim 1 , wherein the hydrophobic layer, in the absence of fluorine or silicone groups, has a water contact angle of greater than 90 degrees.

9. The nozzle plate of claim 1 , comprising a dry film composite layer including a first comprising the hydrophobic layer and a second layer selected from the hydrophobic layer, a hydrophilic polycyclic polyolefin layer derived from an epoxy functionalized polynorbornene, and a photoimageable epoxy resin layer wherein the dry film composite has an overall thickness ranging from about 2 to about 50 microns.