Pressure sensing or force generating device

• US 8,479,585 B2
• Filed: 09/07/2011
• Issued: 07/09/2013
• Est. Priority Date: 09/08/2010
• Status: Active Grant

• Current Assignee: Micropen Technologies Corporation (Heico Corporation)
• Original Assignee: Micropen Technologies Corporation (Heico Corporation)
• Inventors: Shaw-Klein, Lori J.
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): DAVIS HOLLINGTON, OCTAVIA L
• Application Number:
  US13/227,262
• Publication Number:
  US 20120055257A1
• Time in Patent Office: 671 Days
• Field of Search: 737/77
• US Class Current: 73/777
• CPC Class Codes: G01L 1/142 using capacitors
• CPC Class Codes: G01L 1/16 using properties of piezoelectric devices
• CPC Class Codes: G01L 1/18 using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
• CPC Class Codes: H10N 30/074 by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing
• CPC Class Codes: H10N 30/077 by liquid phase deposition
• CPC Class Codes: H10N 30/10513 characterised by the underlying bases, e.g. substrates
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end
• CPC Class Codes: H10N 30/302 Sensors
• CPC Class Codes: H10N 30/306 Cantilevers
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

In one aspect, the present invention relates to a pressure sensing/force generating device comprising a non-planar substrate, a printed pressure sensitive element comprising (a) a piezoelectric material containing ink composition capable of producing a piezoelectric effect/piezoresistive effect and/or (b) a dielectric material containing ink composition capable of producing a capacitive effect. It also includes a first printed electrode comprising a conductive ink composition, and a second printed electrode comprising a conductive ink composition. The first and second electrodes are in electrical contact with the printed pressure sensitive element. The first and second printed electrodes and the printed pressure sensitive element collectively form a pressure sensitive junction, which is coupled to the non-planar substrate. The present invention further relates to medical devices comprising the pressure sensing/force generating device and methods of making such devices.

Claims

1. A pressure sensing/force generating device comprising:

a non-planar substrate;

a printed pressure sensitive element comprising;

a) a piezoactive material containing ink composition capable of producing a piezoelectric effect/piezoresistive effect; and

/or

b) a dielectric material containing ink composition capable of producing a capacitive effect;

a first printed electrode comprising a conductive ink composition; and

a second printed electrode comprising a conductive ink composition, wherein said first and second electrodes are in electrical contact with said printed pressure sensitive element, wherein said first and second printed electrodes and said printed pressure sensitive element collectively form a pressure sensitive junction which is coupled to said non-planar substrate.

2. The pressure sensing/force generating device according to claim 1, wherein the non-planar substrate has an irregular surface.

3. The pressure sensing/force generating device according to claim 1, wherein the non-planar substrate is flexible.

4. The pressure sensing/force generating device according to claim 1 further comprising:

electrical connectors electrically coupled to said first and second printed electrodes.

5. The pressure sensing/force generating device according to claim 4 further comprising:

a voltage reader operably coupled to the electrical connectors to measure or apply voltage between the first and second printed electrodes.

6. The pressure sensing/force generating device according to claim 4 further comprising:

an ohmmeter operably coupled to the electrical connectors to measure the resistance between the first and second printed electrodes.

7. The pressure/sensing force generating device according to claim 4 further comprising:

a capacitance measuring device to measure capacitance between the first and second printed electrodes.

8. The pressure sensing/force generating device according to claim 1 further comprising:

an overcoat layer covering the pressure sensitive junction.

9. The pressure sensing/force generating device according to claim 8, wherein the overcoat layer is formed from a material selected from the group consisting of epoxy, polyacrylate, natural rubber, polyester, polyethylene napthalate, polypropylene, polystyrene, polyvinyl fluoride ethyl-vinyl acetate, ethylene acrylic acid, acetyl polymer, poly(vinyl chloride), silicone, polyurethane, polyisoprene, styrene-butadiene, acrylonitrile-butadiene-styrene, polyethylene, polyamide, polyether-amide, polyimide, polyetherimide, polyetheretherketone, polyvinylidene chloride, polyvinylidene fluoride, polycarbonate, polysulfone, polytetrafuoroethylene, polyethylene terephthalate, polyhydroxyalkanoate, poly(p-xylylene), liquid crystal polymer, polymethylmethacrylate, polyhydroxyethylmethacrylate, polylactic acid, polyhydroxyvalerate, polyphosphazene, poly(∈

-caprolactone), and mixtures or copolymers thereof.

10. The pressure sensing/force generating device according to claim 1 further comprising:

an intermediate layer positioned between the non-planar substrate and the pressure sensitive junction.

11. The pressure sensing/force generating device according to claim 10, wherein the intermediate layer is formed from a material selected from the group consisting of epoxy, polyacrylate, natural rubber, polyester, polyethylene napthalate, polypropylene, polystyrene, polyvinyl fluoride ethyl-vinyl acetate, ethylene acrylic acid, acetyl polymer, poly(vinyl chloride), silicone, polyurethane, polyisoprene, styrene-butadiene, acrylonitrile-butadiene-styrene, polyethylene, polyamide, polyether-amide, polyimide, polyetherimide, polyetheretherketone, polyvinylidene chloride, polyvinylidene fluoride, polycarbonate, polysulfone, polytetrafuoroethylene, polyethylene terephthalate, polyhydroxyalkanoate, poly(p-xylylene), liquid crystal polymer, polymethylmethacrylate, polyhydroxyethylmethacrylate, polylactic acid, polyhydroxyvalerate, polyphosphazene, poly(∈

-caprolactone), and mixtures or copolymers thereof.

12. The pressure sensing/force generating device according to claim 10, wherein the intermediate layer can function as a sealing layer, insulating layer, adhesive layer, structural support layer, or a combination thereof.

13. The pressure sensing/force generating device according to claim 1, wherein the conductive ink compositions independently comprise materials selected from the group consisting of copper, silver, gold, palladium, platinum, nickel, graphite, carbon black, various forms of conductive carbon, conductive ceramics, tin oxide, vanadium pentoxide, doped versions of the tin oxide, doped versions of vanadium oxide, and conductive polymers of polypyrrole, polythiophene, polyaniline, and mixtures thereof.

14. The pressure sensing/force generating device according to claim 1, wherein the piezoactive material containing ink composition is a piezoresistive material or a piezoelectric material.

15. The pressure sensing/force generating device according to claim 14, wherein the piezoactive material containing ink composition is a piezoresistive material comprising a dielectric binder and a conductive filler particle selected from the group consisting of carbon and a metal.

16. The pressure sensing/force generating device according to claim 14, wherein the piezoactive material containing ink composition is a piezoresistive material selected from the group consisting of doped perovskites, zinc oxide, vanadium pentoxide, tin oxide, polypyrrole, polyaniline, polyethylenedioxythiophene, and derivatives or mixtures thereof.

17. The pressure sensing/force generating device according to claim 14, wherein the piezoactive material containing ink composition is a piezoelectric material.

18. The pressure sensing/force generating device according to claim 17, wherein the piezoelectric material is a crystalline ceramic with perovskite structures selected from the group consisting of barium titanate, lead zirconate titanate, lead titanate, bismuth titanate, strontium titanate, lithium niobate, potassium niobate, lithium tantalate, zinc oxide, quartz, and doped forms thereof.

19. The pressure sensing/force generating device according to claim 17, wherein the piezoelectric material is a piezoelectric polymer selected from the group consisting of polyvinylidene fluoride (PVDF), PVDF copolymers, PVDF-hexafluoropropylene (PVDF-HFP), PVDF-trifluoroethylene (PVDF-TrFE), copolymers vinylidene fluoride, odd-numbered polyamides, ferroelectric polymers, Nylon 9, Nylon 11, cellulose, cellulose derivatives, and derivatives or mixtures thereof.

20. The pressure sensing/force generating device according to claim 1, wherein the dielectric material containing ink composition comprises a dielectric material selected from the group consisting of polyurethanes, styrene-butadiene copolymers, acrylonitrile-styrene-butadiene terpolymers, silicones, polyacrylates, epoxies, polyvinyl chloride and derivatives or mixtures thereof.

21. The pressure sensing/force generating device according to claim 1, wherein the conductive ink composition independently comprises a binder selected from the group consisting of poly(vinyl chloride), silicone, polyurethane, polyisoprene, styrene-butadiene, acrylonitrile-butadiene-styrene, polyethylene, polyamide, polyether-amide, polyimide, polyetherimide, polyetheretherketone, polyvinylidene chloride, polyvinylidene fluoride, polycarbonate, polysulfone, polyethylene, polytetrafluoroethylene, polyethylene terephthalate, polyhydroxyalkanoate, poly(p-xylylene), liquid crystal polymer, polymethylmethacrylate, polyhydroxyethylmethacrylate, polylactide, polyglycolide, polyisoprene, poly(∈

-caprolactone), cyanoacrylates, polyvinyl butyral, polyvinyl formal, polyethylene oxide, polyvinyl alcohol, polyvinylpyrrolidone, cellulose esters, cellulose ethers, carrageenan, gelatin, chitosan, and mixtures or copolymers thereof.

22. The pressure sensing/force generating device according to claim 1, wherein the substrate is formed from a material selected from the group consisting of polyester, polyethylene napthalate, polypropylene, polystyrene, polyvinyl fluoride ethyl-vinyl acetate, ethylene acrylic acid, acetyl polymer, poly(vinyl chloride), silicone, polyurethane, polyisoprene, styrene-butadiene, acrylonitrile-butadiene-styrene, polyethylene, polyamide, polyether-amide, polyimide, polyetherimide, polyetheretherketone, polyvinylidene chloride, polyvinylidene fluoride, polycarbonate, polysulfone, polytetrafuoroethylene, polyethylene terephthalate, polyhydroxyalkanoate, poly(p-xylylene), liquid crystal polymer, polymethylmethacrylate, polyhydroxyethylmethacrylate, polylactide, polyglycolide, poly(∈

-caprolactone), and copolymers or mixtures thereof.

23. The pressure sensing/force generating device according to claim 1, wherein the first and second printed electrodes and the printed pressure sensitive element collectively have a thickness of 1 to 500 microns.

24. The pressure sensing/force generating device according to claim 23, wherein the first and second printed electrodes and the printed pressure sensitive element collectively have a thickness of 20 to 100 microns.

25. The pressure sensing/force generating device according to claim 1, wherein said pressure sensing device comprises a plurality of the pressure sensitive junctions.

26. A medical device comprising the pressure sensing/force generating device according to claim 1.

27. The medical device according to claim 26, wherein said medical device comprises a plurality of the pressure sensitive junctions.

28. The medical device according to claim 26, wherein the pressure sensing/force generating device is operably connected to another device to control or monitor the another device'"'"'s function.

29. The medical device according to claim 26, wherein the medical device is selected from the group consisting of endotracheal tubes, endobronchial tubes, cannulae, catheters, balloons, stents, airways, sensors, stimulators, implants, intraocular or contact lenses, cochlear implants, and orthopedic implants or prostheses.

30. A method of forming a pressure sensing/force generating device, the method comprising:

providing a non-planar substrate; and

applying a pressure sensitive junction to said non-planar substrate, said pressure sensitive junction comprising;

a) a printed pressure sensitive element capable of producing a piezoelectric/piezoresistive effect and comprising a piezoactive material containing ink composition; and

/or

b) a printed pressure sensitive element capable of producing a capacitive effect and comprising a dielectric material containing ink composition;

a first printed electrode comprising a conductive ink composition; and

a second printed electrode comprising a conductive ink composition, wherein said first and second electrodes are in electrical contact with the printed pressure sensitive element to collectively form the pressure sensitive junction.

31. The method according to claim 30, wherein said applying the pressure sensitive junction comprises:

applying the printed pressure sensor element to the non-planar substrate;

applying the first printed electrode to the printed pressure sensor element; and

applying the second printed electrode to the printed pressure sensor element.

32. The method according to claim 30, wherein said applying the pressure sensitive junction comprises:

applying the first printed electrode to the non-planar substrate;

applying the printed pressure sensor element to the first printed electrode; and

applying the second printed electrode to the printed pressure sensor element.

33. The method according to claim 30, wherein said applying the pressure sensitive junction comprises:

applying the first printed electrode to the non-planar substrate;

applying the second printed element to the non-planar substrate; and

applying the printed pressure sensor element such that it is in electrical contact with the first and the second printed electrode.

34. The method according to claim 30, wherein said applying the pressure sensitive junction comprises:

applying the first printed electrode to the non-planar substrate;

applying the printed pressure sensor element to the non-planar substrate such that it is in electrical contact with the first printed electrode; and

applying the second printed electrode to the printed pressure sensor element.

35. The method according to claim 30, wherein said applying is carried out by direct writing.

36. The method according to claim 30, wherein said applying is carried out by screen printing, jetting, laser ablation, pressure driven syringe delivery, inkjet or aerosol jet droplet based deposition, laser or ion-beam material transfer, tip based deposition techniques, or flow-based microdispensing techniques.

37. The method according to claim 30 further comprising:

applying an overcoat layer covering the pressure sensitive junction.

38. The method according to claim 30, wherein the non-planar substrate has an irregular surface.

39. The method according to claim 30, wherein the non-planar substrate is flexible.

40. The method according to claim 30 further comprising:

providing an intermediate layer between the non-planar substrate and the pressure sensitive junction.

41. The method according to claim 30, wherein the conductive ink composition, the piezoactive material containing ink composition, and dielectric material containing ink composition independently comprise a solvent selected from the group consisting of paraffinic hydrocarbons, aromatic hydrocarbons, halohydrocarbons, ethers, ketones, aldehydes, esters, nitrogen-containing solvents, sulfur containing solvents, alcohols, polyhydric alcohols, phenols, water, and mixtures thereof.