Introducing material into a printhead enclosure

1. An apparatus comprising:

a jetting assembly including a plurality of nozzles for ejecting droplets of a droplet material on a substrate;

an enclosed print zone within which the jetting assembly prints on the substrate, the enclosed print zone having an inlet formed in a wall of the enclosed print zone, the inlet being different from the plurality of nozzles; and

a mechanism for introducing through the inlet into the enclosed print zone a vaporized environmental material different from the droplet material associated with controlling an environment of the print zone.

2. The apparatus of claim 1 , wherein the environmental material comprises water.

3. The apparatus of claim 1 , wherein the environmental material comprises alcohol.

4. The apparatus of claim 1 , wherein the environmental material comprises MEK.

5. The apparatus of claim 1 , wherein the environmental material comprises a sanitizing agent.

6. The apparatus of claim 1 , wherein the environmental material is adapted to suppress bacterial growth.

7. The apparatus of claim 1 , wherein the vaporized environmental material is soluble in the droplet material.

8. The apparatus of claim 1 , further comprising a sensor placed within the enclosure.

9. The apparatus of claim 8 , wherein the sensor is configured to provide a signal that is used to regulate the environment within the print zone.

10. The apparatus of claim 1 , further comprising a mechanism for removing the environmental material associated with controlling the environment of the print zone.

11. A method of printing comprising:

introducing a vaporized environmental material to an enclosed print zone through an inlet formed in a wall of the enclosed print zone, and

jetting droplets of a droplet material on a substrate from a nozzle within the print zone while the vaporized environmental material is present and in a vicinity of the nozzle to prevent the droplet material from drying in the nozzle.

12. The method of claim 11 wherein the environmental material comprises water.

13. The method of claim 11 wherein the environmental material comprises alcohol.

14. The method of claim 11 wherein the environmental material comprises MEK.

15. The method of claim 11 wherein the environmental material comprises a sanitizing agent.

16. The method of claim 11 wherein the environmental material is adapted to suppress bacterial growth.

17. The method of claim 11 further comprising selecting the environmental material to be soluble in the droplet material.

18. The method of claim 11 , further comprising placing a sensor within the enclosed print zone.

19. The method of claim 18 , further comprising configuring the sensor to provide a signal that is used to regulate an environment within the print zone.

20. The method of claim 11 , further comprising removing the environmental material from the print zone.

21. An apparatus comprising:

a jetting assembly including a plurality of nozzles to eject droplets of a droplet material to print on a substrate within an enclosed print zone,

an inlet formed in a wall of the enclosed print zone different from the plurality of nozzles, and

a mechanism to control an environment within the print zone by introducing a vaporized environmental material, different from the droplet material, through the inlet and into the print zone while the droplets are ejected.

22. The apparatus of claim 21 , wherein the vaporized environmental material is soluble in the droplet material.

23. The apparatus of claim 21 , further comprising a sensor placed within the enclosed print zone.

24. The apparatus of claim 21 , further comprising a mechanism for removing the environmental material associated with controlling the environment of the print zone.