Granted Patent B2

US 9,233,533 · App. 14/018,403 · Granted Jan 12, 2016

Abstract

Claims (44)

1. An inkjet printhead comprising a front face having a polymer coating, the polymer coating comprising an oleophobic grafted polymer comprising:

a crosslinked fluoroelastomer; and

a perfluorinated polyether grafted to the crosslinked fluoroelastomer;

wherein the crosslinked fluoroelastomer is crosslinked with an aminofunctionalized silane, the aminofunctionalized silane comprising an aminoalkylsilane-modified polysiloxane.

2. The inkjet printhead of claim 1 , wherein the oleophobic grafted polymer has a structure of formula I:

wherein FE is a fluoroelastomer;

PFPE is a perfluorinated polyether;

L is a linker;

m, n, and o are independently an integer from 1 to 10;

each incidence of R 1 and R 2 is independently a substituted or unsubstituted C 1 -C 6 alkyl,

R 3 and R 4 are independently an optionally fluorinated C 1 -C 6 alkyl or an optionally fluorinated C 1 -C 6 alkoxy.

3. The inkjet printhead of claim 1 , wherein the polymer coating has an ink contact angle of at least about 50 degrees.

4. The inkjet printhead of claim 1 , wherein the polymer coating has an ink slide angle of less than about 30 degrees.

5. The inkjet printhead of claim 1 , wherein the polymer coating is characterized by being stable at 290° C. at 350 psi.

6. A process for making an oleophobic grafted polymer coating on a printhead comprising:

crosslinking a fluoroelastomer with an aminofunctionalized silane, wherein the aminofunctionalized silane comprises an aminoalkylsilane-modified polysiloxane

grafting an alkoxysilane-terminated perfluorinated polyether to the crosslinked fluoroelastomer to form a oleophobic grafted polymer; and

coating the oleophobic grafted polymer on a printhead front face.

7. The process of claim 6 , wherein the oleophobic grafted polymer has a final structure of formula I:

wherein FE is a fluoroelastomer;

PFPE is a perfluorinated polyether;

L is a linker;

m, n, and o are independently an integer from 1 to 10

each incidence of R 1 and R 2 is independently an optionally fluorinated C 1 -C 6 alkyl,

R 3 and R 4 are independently an optionally fluorinated C 1 -C 6 alkyl or an optionally fluorinated C 1 -C 6 alkoxy.

8. The process of claim 6 , wherein the crosslinking step is performed in the presence of the alkoxysilane-terminated perfluorinated polyether.

9. The process of claim 8 , wherein a ratio of the aminofunctionalized silane to the alkoxysilane-terminated perfluorinated polyether is in a range from about 0.5:1 to about 3:1.

10. The process of claim 9 , wherein an amount of the aminofunctionalized silane relative to the fluoroelastomer is in a range from about 2 pph to about 10 pph.

11. An inkjet printhead comprising a front face having a polymer coating, the polymer coating comprising a structure of formula I:

wherein FE is a fluoroelastomer;

PFPE is a perfluorinated polyether;

L is a linker;

m, and o are independently an integer from 3 to 8;

n is an integer from 1 to 10;

each incidence of R 1 and R 2 is independently a substituted or unsubstituted C 1 -C 6 alkyl,

R 3 and R 4 are independently an optionally fluorinated C 1 -C 6 alkyl or an optionally fluorinated C 1 -C 6 alkoxy.

12. The inkjet printhead of claim 11 , wherein the linker L comprises a C 1 -C 6 alkyl terminating in a functional group capable of covalently linking to a terminal hydroxyl functionality group of the perfluorinated polyether.

13. The inkjet printhead of claim 11 , wherein the fluoroelastomer (FE) is a polymer comprising a monomer unit selected from the group consisting of vinylidene fluoride, tetrafluorethylene, hexafluoropropylene, perfluoromethylvinylether and combinations thereof.

14. The inkjet printhead of claim 11 , wherein the fluoroelastomer (FE) has a fluorine content of at least about 65 percent.

15. The inkjet printhead of claim 11 , wherein the fluoroelastomer (FE) has a molecular weight in a range from about 50,000 to about 70,000 daltons as measured by gel permeation chromatography.

16. The inkjet printhead of claim 11 , wherein the perfluorinated polyether (PFPE) is an alkoxysilane-terminated perfluorinated polyether having an average molecular weight in a range from about 1,500 daltons to about 2,500 daltons.

17. The inkjet printhead of claim 11 , wherein the polymer coating has an ink contact angle of at least about 50 degrees.

18. The inkjet printhead of claim 11 , wherein the polymer coating has an ink slide angle of less than about 30 degrees.

19. The inkjet printhead of claim 11 , wherein the polymer coating is characterized by being stable at 290° C. at 350 psi.

Assignments (10)