Curable thermally ejectable printing fluid

1. A curable printing fluid composition for a thermal fluid ejection device, comprising:

a curable liquid-phase monomer;

a substantially nonaqueous volatile driver fluid capable of being vaporized by a thermal fluid ejection printhead;

an initiator;

a phosphate ester resistor protectant; and

a colorant comprising a dispersed pigment.

2. The composition of claim 1 , wherein the liquid-phase monomer comprises an acrylic monomer.

3. The composition of claim 2 , wherein the liquid-phase monomer further comprises a mixture of two or more acrylic monomers, wherein at least one of the acrylic monomers is a monofunctional monomer and wherein at least one other of the acrylic monomers is a difunctional monomer.

4. The composition of claim 1 , wherein the monomer is the driver fluid.

5. The composition of claim 1 , wherein the driver fluid comprises at least one of methanol, ethanol, acetone, methyl acetate and ethyl acetate.

6. The composition of claim 5 , wherein the composition comprises approximately 50% or less driver fluid by total composition volume.

7. The composition of claim 5 , wherein the composition comprises approximately 15-35% driver fluid by total composition volume.

8. The composition of claim 1 , wherein the phosphate ester resistor protectant has a general formula of (R—O-E x ) y PO (4-y) H (3-y) , wherein R is a branched hydrocarbon, unbranched hydrocarbon, or perfluorinated hydrocarbon moiety with at least eight carbons, E is CH 2 CH x O or C(CH 3 )HCH 2 O, x is zero or an integer greater than zero, and y is an integer from 1 to 3.

9. The composition of claim 1 , wherein the composition comprises approximately 1-6% resistor protectant compound by total composition volume.

10. The composition of claim 1 , further comprising an oligomer.

11. The composition of claim 10 , wherein the oligomer is selected from epoxies, polyesters, acrylics, and acrylic urethanes.

12. The composition of claim 10 , wherein the composition comprises approximately 0.1-80 weight percent of oligomer by total composition weight.

13. The composition of claim 1 , wherein the composition is UV-curable and wherein the initiator comprises a photoinitiator.

14. The composition of claim 13 , wherein the photoinitiator comprises at least one of benzophenone, trimethylbenzophenone, methylbenzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzyl dimethyl ketal, isopropyl thiooxanthone, 1-hydroxy-cyclohexyl-phenyl-ketone, ethyl 4-(dimethylamino)benzoate, 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2,2-dimethoxy-1,2-diphenylethan-1-one, phosphine oxide, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-dimethylamino-2-(4-methyl-benzy)-1-(4-morpholin-4-yl-pheny)-butan-1-one), amine acrylate, acrylic ester, trimethylbenzoyldiphenylphosphine oxide, a-hydroxyketones, and benzophenone derivatives).

15. The composition of claim 1 , wherein the composition comprises 0.1-20 percent photoinitiator by total composition weight.

16. The composition of claim 1 , further comprising an adhesion promoter.

17. The composition of claim 16 , wherein the adhesion promoter comprises a 1,2 butyl glycol diacrylic ester.

18. The composition of claim 16 , wherein the composition comprises 0.1 to 20 percent adhesion promoter by total composition weight.

19. The composition of claim 1 , wherein the composition has a viscosity of less than or equal to approximately 20 cps under conditions of use in a thermal fluid ejection device.

20. The composition of claim 1 , wherein the monomer has a viscosity of approximately equal to or less than 15 cps under conditions of use in a thermal fluid ejection device.

21. The composition of claim 1 , wherein the composition has a surface tension of between approximately 20-50 dyne/cm.

22. A thermal inkjet printing cartridge comprising a printhead and a UV-curable printing fluid composition for a thermal fluid ejection device, the printing fluid composition comprising:

at least one di-functional acrylic monomer;

at least one substantially nonaqueous driver fluid present in an amount of 0.1-50 weight percent by total composition weight;

at least one photoinitiator and at least one amine present in a combined amount of 0.1-18 weight percent by total composition weight;

a dispersed pigment; and

at least one phosphate ester resistor protectant present in an amount of 0.1-10 weight percent by total composition weight.

23. The cartridge of claim 22 , wherein the composition has a viscosity equal to or less than approximately 20 cps.

24. The cartridge of claim 22 , wherein the composition has a surface tension of between approximately 20-50 dyne/cm.

25. The cartridge of claim 22 , further comprising a mono-functional acrylic monomer present in an amount of 0.1-90 weight percent by total composition weight.

26. The cartridge of claim 22 , wherein the di-functional acrylic monomer is present in an amount of 0.1-90 weight percent by total composition weight.

27. The cartridge of claim 22 , wherein the substantially nonaqueous driver fluid comprises at least one of a lower alcohol, a lower acetate, and acetone.

28. The cartridge of claim 22 , wherein the substantially nonaqueous driver fluid is present in an amount of 5-40 weight percent by total composition weight.

29. The cartridge of claim 22 , wherein the photoinitiator is present in an amount of 5-20 weight percent by total composition weight.

30. The cartridge of claim 22 , wherein the phosphate ester resistor protectant has a general formula of (R—O-E x ) y PO (4-y )H (3-y) , wherein R is a branched hydrocarbon, unbranched hydrocarbon, or perfluorinated hydrocarbon moiety with at least eight carbons, E is CH 2 CH x O or C(CH 3 )HCH 2 O, x is zero or an integer greater than zero, and y is an integer from 1 to 3.

31. The cartridge of claim 22 , wherein the resistor protectant is present in an amount of 2-6 weight percent by total composition weight.

32. The cartridge of claim 22 , wherein the composition further comprises a colorant.

33. A curable, thermally-ejectable printing fluid composition, comprising:

at least one liquid-phase monomer;

at least one substantially nonaqueous driver fluid vaporizable by a thermal fluid ejection printhead;

one or more photoinitiators;

one or more amine coinitiators, wherein the one or more photoinitiators and the one or more amine coinitiators are included in the printing fluid at a concentration of 12-18 parts per total composition weight;

a pigment dispersion stabilized by the one or more amine coinitiators; and

at least one phosphate ester resistor protectant, wherein the composition is curable by exposure to at least one of electromagnetic energy and particle energy, and wherein the composition has a viscosity of approximately 1-20 cps under conditions of use in a thermal fluid ejection device and a surface tension of approximately 20-50 dyne/cm.

34. The composition of claim 33 , wherein the at least one monomer comprises an acrylic monomer.

35. The composition of claim 34 , wherein the acrylic monomer comprises a mono-functional acrylic monomer and a di-functional acrylic monomer.

36. The composition of claim 33 , wherein the at least one driver fluid comprises at least one of methanol, ethanol, a propanol, a butanol, acetone, methyl acetate, and ethyl acetate.

37. The composition of claim 33 , wherein the at least one phosphate ester resistor protectant has a general formula of (R—O-E x ) y PO (4-y) H (3-y) , wherein R is a branched hydrocarbon, unbranched hydrocarbon, or perfluorinated hydrocarbon moiety with at least eight carbons, E is CH 2 CH x O or C(CH 3 )HCH 2 O, x is zero or an integer greater than zero, and y is an integer from 1 to 3.

38. The composition of claim 33 , further comprising a colorant.

39. The composition of claim 33 , wherein the coinitiator is present in an amount of 4 percent by total composition weight.

40. The composition of claim 33 , further comprising an adhesion promoter.