received by the International Bureau on 22 September 2016 (22.09.16)

1. A printing system comprising:

a printer head configured to deposit ink on a substrate;

a first light source configured to only emit electromagnetic radiation of subtype C (UVC) (paras. [0031] and [0056]);

a second light source configured to emit electromagnetic radiation of subtype

A (UVA), subtype B (UVB), subtype V (UVV), or a combination thereof, wherein the ink deposited by the printer head on the substrate is predominantly exposed to the first light source prior to exposure to the second light source.

2. The printing system of claim 1 , wherein the ink is an ultraviolet energy curable ink.

3. The printing system of claim 1 , wherein the ink is a water-based diluted ink or a solvent-based diluted ink, and the diluted ink has 30% or less residual solid by weight.

4. The printing system of claim 3, further comprising:

a dryer that wholly or partially removes the water from the water-based diluted ink or the solvent from the solvent-based diluted ink prior to exposure to the first light source.

5. The printing system of claim 1 , wherein the ink is void of photoinitiator.

6. The printing system of claim 1 , wherein the relative amount of photoinitiator in the ink exceeds 5% by weight.

7. The printing system of claim 1 , wherein the ink comprises a first photoinitiator adapted to absorb a first range of wavelengths and a second photoinitiator adapted to absorb a second range of wavelengths.

8. The printing system of claim 1 , wherein the first light source and the second light source form a single mixed light source, the mixed light source including a first plurality of light emitting diodes configured to emit electromagnetic radiation of subtype C (UVC) and a second plurality of light emitting diodes configuted to emit electromagnetic radiation of subtype A (UVA), subtype B (UVB), subtype V (UVV), or the combination thereof, and wherein the first plurality of light emitting diodes and the second plurality of light emitting diodes are arranged such that newly deposited ink is predominantly exposed to the first plurality of light emitting diodes before the second plurality of light emitting diodes.

9. The printing system of claim 1 , wherein the first light source emits electromagnetic radiation of subtype C (UVC) from a flourescent bulb, a light emitting diode, a low pressure bulb, a medium pressure bulb, an excimer lamp, or an excimer laser.

10. The printing system of claim 1 , wherein the first light source is configured to emit electromagnetic radiation of subtype C (UVC) having a wavelength in a range of 250 to 260 nanometers.

1 1. The printing system of claim 1 , wherein the first light source is configured to emit electromagnetic radiation of subtype C (UVC) having a power density of greater than or equal to 50 milliwatts per square centimeter.

12. The printing system of claim 1 , wherein the printer head, first light source, and second light source are coupled together within a carriage.

29

13. The printing system of claim 12, wherein the first light source is directly adjacent to the printer head and the second light source is directly adjacent to the first light source.

14. The printing system of claim 12, wherein the printer head is located between two first light sources, each of the first light sources being adjacent to a second light source positioned opposite the printer head, such that ink deposited by the printer head is predominantly exposed to one of the first light sources prior to exposure to the adjacent second light source.

15. The printing system of claim 13, wherein the ink is exposed to the first light source and the second light source when the carriage moves in relation to the substrate.

16. The printing system of claim 13, wherein the ink is exposed to the first light source and the second light source when the substrate moves in relation to the carriage.

17. The printing system of claim 1 , wherein the printer head is substantially stationary and the substrate is transported relative to the printer head.

18. The printing system of claim 1 , further comprising:

filter means configured to reduce oxygen concentration in a region between the surface of the ink and the first light source, such that the region is between 1 % and 20% oxygen by volume.

19. A method comprising:

depositing ink on a substrate using a printer head; and

curing the ink by exposing the ink to a first light source and a second light source,

30 wherein the first light source is configured to only emit electromagnetic radiation of subtype C (UVC) (paras. [0031] and [0056]) and the second light source is configured to emit electromagnetic radiation of subtype A (UVA), subtype B (UVB), subtype V (UVV), or a combination thereof, and

further wherein the ink deposited by the printer head on the substrate is predominantly exposed to the first light source prior to the second light source.

20. The method of claim 19, further comprising:

drying the ink using one or more dryers attached to either side of a reciprocating carriage, one or more stationary dryers positioned downstream in the media feed direction, or any combination thereof,

wherein the ink deposited by the printer head on the substrate is predominantly exposed to the one or more dryers prior to the first light source.

21. The method of claim 19, wherein the ink is an ultraviolet energy curable ink.

22. The method of claim 19, wherein the ink is a water-based diluted ink or a solvent-based diluted ink, and the diluted ink has 30% or less residual solid by weight.

23. The method of claim 19, wherein the relative amount of photoinitiator in the ink exceeds 5% by weight.

24. The method of claim 19, wherein the first light source is configured to emit electromagnetic radiation of subtype C (UVC) having a wavelength in a range of 250 to 260 nanometers.

31

25. The method of claim 19, further comprising reducing oxygen concentration in a region between the surface of the ink and the first light source, such that the region is between 1 % and 20% oxygen by volume.

26. A method of manufacturing a printing system comprising:

providing a printer head configured to deposit ink on a substrate; and coupling the printer head to a first light source and a second light source, wherein the first light source is configured to only emit electromagnetic radiation of subtype C (UVC) (paras. [0031] and

[0056]) and the second light source is configured to emit electromagnetic radiation of subtype A (UVA), subtype B (UVB), subtype V (UVV), or a combination thereof, and

further wherein the first light source, the second light source, and the printer head are coupled such that ink deposited by the printer head on the substrate is exposed to the first light source prior to the second light source.

27. The method of claim 26, further comprising:

providing a storage medium containing compressed air; and

coupling the storage medium to a filter configured to remove oxygen from the compressed air, thereby creating filtered air,

wherein the filtered air is injected into a region between the surface of the ink and the first light source, thereby reducing oxygen concentration in the region.

28. The method of claim 27, wherein the oxygen concentration is between 1 % and 20% by volume.

29. A printing system comprising:

a printer head configured to deposit an ink layer on a substrate;

32 a light source configured to emit a first set of wavelengths of electromagnetic radiation of subtype C (UVC) having a wavelength not exceeding 250 nanometers (paras. [0024]-[0025] and [0034]);

wherein at least an upper portion of the ink layer deposited by the printer head on the substrate is cured by the first set of wavelengths.

30. The printing system of claim 29, further comprising:

a dryer configured to remove water or solvent from the ink prior to curing, the ink comprising a water-based ink formulation or a solvent-based ink formulation.

31. The printing system of claim 29, wherein the light source is further configured to emit a second set of wavelengths of electromagnetic radiation of subtype A (UVA), subtype B (UVB), subtype V (UVV), or a combination thereof to cure a lower portion of the ink layer, and wherein the ink layer is exposed to the first set of wavelengths and the second set of wavelengths simultaneously.

33