Capillary devices for determination of surface characteristics and contact angles and methods for using same

• US 20040187565A1
• Filed: 11/06/2003
• Published: 09/30/2004
• Est. Priority Date: 11/06/2002
• Status: Active Grant

• Current Assignee: Stephen P. Sutton
• Original Assignee: Stephen P. Sutton
• Inventors: Sutton, Stephen P.
• Granted Patent: US 7,024,921 B2
• Time in Patent Office: Days
• US Class Current: 73/104
• CPC Class Codes: G01N 13/02 Investigating surface tension of liquids
• CPC Class Codes: G01N 2013/0208 by measuring contact angle

Abstract

Devices are presented which allow determination of unknown surface properties through the creation of a channel capillary, comprised in part of the subject surface or surfaces, and measurement of the capillary pressure created by a test fluid within the resultant channel. In various embodiments of the invention, a channel is created in a reference material which is bonded, through some mechanism, to the test surface in order to create a narrow capillary channel. In other embodiments of the invention, the capillary channel is created with test surfaces on either side of standoff strips which space the surfaces a precise distance from one another. Methods are presented for using these capillaries through immersion, along their length, in a bath of test fluid, such that the resultant fluid level provides a measure of capillary pressure. Being, in part, a consequence of the contact angle between the test fluid and the surface or surfaces under consideration, the capillary pressure is a convenient measure of surface properties inherently related to printability, affinity for adhesives, surface contamination by foreign substances, surface roughness, and the like. Devices are presented which allow measurement of test fluid height within the capillary, both in situations where a static equilibrium is achieved, and in situations where a dynamic contact angle is operative as the fluid rises or falls within the capillary.

Claims

1. A reference channel capillary device comprising:

an open capillary channel embedded within a surface of a supportive materials system, the capillary channel having a cross sectional geometry sufficient to create an open channel, the capillary device being configured to form a closed capillary against an adjacent surface.

2. A reference channel capillary device as defined in claim 1, wherein the surface in which the open capillary channel is embedded is configured to adhere to an adjacent surface.

3. A reference channel capillary device as defined in claim 2, wherein the surface in which the open capillary channel is embedded includes an adhesive coating.

4. A reference channel capillary device as defined in claim 2, wherein the supportive materials system comprises a polymer having adhesive properties that enables the surface of the supportive materials system to adhere to an adjacent surface.

5. A reference channel capillary device as defined in claim 1, wherein the open capillary channel is embedded within a planar surface.

6. A reference channel capillary device as defined in claim 1, wherein the open capillary channel is embedded within a curved surface.

7. A reference channel capillary device as defined in claim 1, wherein the open capillary channel is embedded within a planar surface and has a rectangular cross section with a depth of less than about 0.020 inches and a width greater than 10 times the depth.

8. A reference channel capillary device as defined in claim 1, wherein the supportive materials system is made from a polymer.

9. A reference channel capillary device as defined in claim 1, wherein the supportive materials system comprises glass.

10. A reference channel capillary device as defined in claim 1, wherein the supportive materials system comprises a ceramic material.

11. A reference channel capillary device as defined in claim 1, wherein the supportive materials system comprises a metal.

12. A reference channel capillary device as defined in claim 1, wherein the supportive materials system comprises a semiconductor.

13. A reference channel capillary device as defined in claim 1, wherein the supportive materials system comprises a thermoplastic elastomer.

14. A reference channel capillary device as defined in claim 1, wherein the device is transparent or translucent.

15. A reference channel capillary device as defined in claim 1, wherein a surface of the capillary channel is coated with a layer of material through electrodeposition, evaporation, sputtering, plasma treatment, or chemical vapor deposition.

16. A reference channel capillary device as defined in claim 1, wherein a surface of the capillary channel comprises a polymer which is bonded to the supportive materials system.

17. A reference channel capillary device as defined in claim 1, wherein the supportive materials system is made from a material comprising a styrene ethylene-butylene styrene block copolymer.

18. A reference channel capillary device as defined in claim 17, wherein the styrene ethylene-butylene styrene block copolymer is mixed with a mineral oil and a paraffin wax.

19. A reference channel capillary device comprising:

an open capillary channel embedded within a supportive materials system, the capillary channel having a cross sectional geometry sufficient to create an open channel, the capillary device being configured to form a closed capillary against an adjacent surface, the capillary device further being configured to be placed against a curved adjacent surface for forming the closed capillary, the supportive materials system being made from a material comprising a polymer, a glass, a semiconductor, a ceramic, a metal, a thermoplastic elastomer, or mixtures thereof.

20. A reference channel capillary device as defined in claim 19, wherein the device is transparent or translucent.

21. A reference channel capillary device as defined in claim 19, wherein a surface of the capillary channel is coated with a layer of material through electrodeposition, evaporation, sputtering, plasma treatment, or chemical vapor deposition.

22. A reference channel capillary device as defined in claim 19, wherein a surface of the capillary channel comprises a polymer which is bonded to the supportive materials system.

23. A reference channel capillary device comprising:

an open capillary channel defined by a planar surface of a supportive materials system, the capillary device being configured to form a closed capillary against an adjacent planar surface, the capillary channel having a rectangular cross section with a depth of less than about 0.02 inches and a width greater than about 10 times the depth, the supportive materials system being made from a material comprising a polymer, a glass, a semiconductor, a ceramic, a metal, a thermoplastic elastomer, or mixtures thereof.

24. A reference channel capillary device as defined in claim 23, wherein the device is transparent or translucent.

25. A reference channel capillary device as defined in claim 23, wherein a surface of the capillary channel is coated with a layer of material through electrodeposition, evaporation, sputtering, plasma treatment, or chemical vapor deposition.

26. A reference channel capillary device as defined in claim 23, wherein a surface of the capillary channel comprises a polymer which is bonded to the supportive materials system.

27. A spacer wall capillary device comprising a first spacer element spaced from a second spacer element, the spacer elements being configured to be attached to two opposing adjacent surfaces, the spacer elements holding the surfaces apart thereby producing a capillary.

28. A spacer wall capillary device, as defined in claim 27, wherein the spacer elements have a thickness of less than about 0.020 inches.

29. A spacer wall capillary device as defined in claim 27, wherein the two spacer elements are initially held some distance apart by a support to facilitate application and creation of a capillary between parallel surfaces.

30. A spacer wall capillary device as defined in claim 27, wherein the spacer elements are made from a material comprising sheets of a polymer, a metal, a ceramic, a glass, or a semiconductor.

31. A spacer wall capillary device as defined in claim 27, wherein the spacer elements comprise a thermoplastic elastomer.

32. A method for analysis of surface properties comprising:

providing a capillary device;

placing the capillary device adjacent to a surface;

contacting the capillary with a fluid; and

measuring the height to which the fluid rises in the capillary.

33. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized as a measure of surface printability.

34. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized as a measure of surface wettability.

35. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized as a measure of bondability.

36. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized as a measure of surface affinity for other substances.

37. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized as a measure of surface contamination by foreign substances.

38. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized as a measure of surface roughness.

39. A method for analysis of surface properties as defined in claim 32, wherein the height to which the fluid rises is utilized to characterize and identify surface coatings.

40. A method for analysis of surface properties comprising:

providing a capillary device;

placing the capillary device adjacent to a surface;

contacting the capillary with a fluid;

measuring the height to which the fluid rises in the capillary; and

determining a contact angle between the fluid and the surface from the amount the fluid rises in the capillary.

41. A method for analysis of surface properties comprising:

providing a capillary device;

positioning the capillary device adjacent a surface to form a capillary;

placing the capillary in a bath containing a fluid under dynamic conditions such that fluid flows into and out of the capillary due to relative motion of the capillary and the bath surface; and

measuring the height of fluid within the capillary relative to the level of fluid in the bath.

42. A method for analysis of surface properties, as defined in claim 41, wherein the height of fluid within the capillary, relative to the bath surface, is used to determine an advancing or receding contact angle.

43. A method for analysis of surface properties as defined in claim 41, wherein the height of fluid within the capillary, relative to the bath surface is used as a relative measure of how the advancement or recession of fluid over a given surface impacts fluid interaction with the surface.

44. A device for measurement of dynamic wetting effects at a surface comprising:

a capillary device defining an open capillary channel, the capillary device being configured to adhere to an adjacent surface for forming a closed capillary against the surface;

a reference bath for submersion of the closed capillary formed between the capillary device and the adjacent surface;

means for causing recession or advancement of a fluid within the capillary due to motion of the capillary relative to a fluid bath surface; and

means for measurement of fluid height within the capillary relative to the fluid bath surface.

45. A device for measurement of dynamic wetting effects at a surface as defined in claim 44, wherein the capillary moves on a mechanical stage.

46. A device for measurement of dynamic wetting effects at a surface as defined in claim 44, wherein the fluid height in the bath is altered by controlled flow of fluid into, or out of, the bath.

47. A device for measurement of the dynamic wetting effects at a surface as defined in claim 44, wherein the height of fluid within the capillary, relative to the bath surface, is measured using video imaging.

48. A device for measurement of the dynamic wetting effects at a surface as defined in claim 44, wherein the height of fluid within the capillary, relative to the bath surface, is measured using a device that measures electrical resistance or impedance.

49. A device for measurement of the dynamic wetting effects at a surface as defined in claim 44, wherein the height of fluid within the capillary, relative to the bath surface, is measured by an optical device.

50. A device for measurement of the dynamic wetting effects at a surface as defined in claim 44, wherein the height of fluid within the capillary, relative to the bath surface, is measured acoustically by an acoustic device.

51. A device for measurement of the dynamic wetting effects at a surface as defined in claim 45, wherein the rate of motion of the mechanical stage is controlled by a microprocessor.

52. A device for measurement of the dynamic wetting effects at a surface as defined in claim 46, wherein the height of fluid within the bath is controlled by a microprocessor.

53. A device for measurement of the dynamic wetting effects at a surface as defined in claim 44, wherein the height of fluid within the capillary, relative to the bath surface, is used to calculate dynamic contact angle.