FLEXIBLE CIRCUITS HAVING INK-RESISTANT COVERCOATS

Abstract

A circuit article for use with an inkjet printer pen. The circuit article comprises a flexible circuit having a plurality of conductive traces disposed on a dielectric film, an adhesive film disposed adjacent the dielectric film of the flexible circuit, and a carrier film disposed adjacent the first adhesive film, opposite of the flexible circuit. The adhesive film is derived from a cross-linkable precursor comprising an epoxidized aromatic-diene block copolymer and a thermal-curing agent.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an inkjet printer pen.

FIG. 2 is an exploded view showing a rear portion of a flexible circuit and a covercoat, which are removed from the inkjet printer pen.

FIG. 3A is a sectional view of section 3-3 taken in FIG. 2, showing the interlayer orientations between a pen body, the flexible circuit, and the covercoat.

FIG. 3B is a first alternative embodiment of a sectional view of section 3-3 taken in FIG. 2, in which the covercoat does not include a tie layer.

FIG. 3C is a second alternative embodiment of a sectional view of section 3-3 taken in FIG. 2, in which the flexible circuit and the covercoat are inverted.

FIG. 4 is a flow diagram showing a method for forming the flexible circuit and the bonding component for use with the inkjet printer pen.

FIG. 5 is a graphical plot of an electrified ink immersion test for exemplary samples of the present invention and comparative examples.

Claims

1. A circuit article for use with an inkjet printer pen, the circuit article comprising: a flexible circuit having a plurality of conductive traces disposed on a dielectric film;an adhesive film disposed adjacent the dielectric film of the flexible circuit, the adhesive film being derived from a cross-linkable precursor comprising an epoxidized aromatic-diene block copolymer and a thermal-curing agent; anda carrier film disposed adjacent the adhesive film, opposite of the flexible circuit.

2. The circuit article of claim 1, wherein the epoxidized aromatic-diene block copolymer comprises an epoxidized styrene-butadiene block copolymer.

3. The circuit article of claim 2, wherein the epoxidized styrene-butadiene block copolymer comprises about 30% by weight to about 80% by weight epoxidized butadiene block.

4. The circuit article of claim 1, wherein the epoxidized aromatic-diene block copolymer has an epoxy equivalent weight ranging from about 100 to about 2,200.

5. The circuit article of claim 1, wherein the thermal-curing agent comprises a quaternary hexafluoroantimonate salt.

6. The circuit article of claim 1, wherein the carrier film comprises a material selected from the group consisting of poly(ethylene naphthalate), poly(ethylene terephthalate, polyaramids, polyimides, and combinations thereof.

7. The circuit article of claim 1, wherein the carrier film is treated with a treatment technique selected from the group consisting of flash lamp treatments, corona treatments, plasma treatments, flame treatments, chemical treatments, and combinations thereof.

8. The circuit article of claim 1, further comprising an adhesive tie layer disposed adjacent the carrier film, opposite the adhesive film.

9. The circuit article of claim 1 wherein the thermal curing agent is a cationic curing agent.

10. The circuit article of claim 9 wherein the thermal curing agent further comprises a free radical curing agent.

11. The circuit article of claim 10, wherein the free radical curing agent is a peroxide.

12. The circuit article of claim 10, wherein the free radical curing agent is dicumyl peroxide.

13. An inkjet printer pen comprising: a pen body configured to store and dispense ink;a carrier film adhered to the pen body;an adhesive film disposed adjacent the carrier film, opposite the body, wherein the adhesive film is derived from a cross-linkable precursor comprising an epoxidized aromatic-diene block copolymer and a thermal-curing agent;a flexible circuit having a plurality of conductive traces disposed on a dielectric film, the dielectric film being disposed adjacent the adhesive film.

14. The inkjet printer pen of claim 13, wherein the epoxidized aromatic-diene block copolymer comprises an epoxidized styrene-butadiene block copolymer.

15. The inkjet printer pen of claim 13, wherein the epoxidized aromatic-diene block copolymer has an epoxy equivalent weight ranging from about 100 to about 2,200.

16. The inkjet printer pen of claim 13, wherein the thermal-curing agent comprises a quaternary hexafluoroantimonate salt.

17. The inkjet printer pen of claim 13, wherein the carrier film comprises a material selected from the group consisting of poly(ethylene naphthalate), poly(ethylene terephthalate, polyimides, polyaramid, and combinations thereof.

18. The inkjet printer pen of claim 13, wherein the carrier film is treated with a treatment technique selected from the group consisting of flash lamp treatments, corona treatments, plasma treatments, flame treatments, chemical treatments, and combinations thereof.

19. The inkjet printer pen of claim 13 wherein the thermal curing agent is a cationic curing agent.

20. The circuit article of claim 19 wherein the thermal curing agent further comprises a free radical curing agent.

21. The inkjet printer pen of claim 20, wherein the free radical curing agent is a peroxide.

22. The inkjet printer pen of claim 20, wherein the free radical curing agent is dicumyl peroxide.

23. A method of forming a circuit article for use with an inkjet printer pen body, the method comprising: coating a cross-linkable precursor onto a carrier film, the cross-linkable precursor comprising an epoxidized styrene-diene block copolymer and a thermal-curing agent;laminating a flexible circuit adjacent the cross-linkable precursor, wherein the flexible circuit has a plurality of conductive traces that are encapsulated by the cross-linkable precursor; andthermal curing the cross-linkable precursor.

24. The method of claim 23, wherein the thermal curing is performed at a temperature of about 100° C. or less.

25. The method of claim 23, further comprising removing an excess portion of the cross-linkable precursor.

26. The method of claim 25, wherein removing the excess portion of the cross-linkable precursor comprises spraying the cross-linkable precursor with at least one solvent.

27. The method of claim 23, wherein the epoxidized aromatic-diene block copolymer comprises an epoxidized styrene-butadiene block copolymer.

28. The method of claim 23, wherein the carrier film comprises a material selected from the group consisting of poly(ethylene naphthalate), poly(ethylene terephthalate, polyimides, polyaramid, and combinations thereof.

29. The method of claim 23 wherein the thermal curing agent is a cationic curing agent.

30. The circuit article of claim 29 wherein the thermal curing agent further comprises a free radical curing agent.