Patterned Coatings Having Extreme Wetting Properties and Methods of Making

• US 20070166513A1
• Filed: 09/11/2006
• Published: 07/19/2007
• Est. Priority Date: 11/08/2005
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Cohen, Robert, Rubner, Michael, Zhai, Lei, Sheng, Xiaoxia
• Granted Patent: US 8,153,233 B2
• Time in Patent Office: Days
• US Class Current: 428/141
• CPC Class Codes: B05D 1/18 performed by dipping
• CPC Class Codes: B05D 5/04 to obtain a surface receptive to ink or other liquid B05D5/02, B41M5/52 take precedence
• CPC Class Codes: B05D 5/06 to obtain multicolour or other optical effects B05D5/02 takes precedence
• CPC Class Codes: C03C 17/3405 with at least two coatings of organic materials C03C17/36, C03C17/42 take precedence
• CPC Class Codes: C03C 2217/42 consisting of particles only
• CPC Class Codes: C03C 2217/425 consisting of a porous layer
• CPC Class Codes: C03C 2217/478 Silica
• CPC Class Codes: C03C 2217/75 Hydrophilic and oleophilic coatings
• CPC Class Codes: C08L 33/02 Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• CPC Class Codes: C09D 139/00 Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen; Coating compositions based on derivatives of such polymers
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/24372 Particulate matter
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

A surface with superhydrophobic and hydrophilic or superhydrophilic regions can be made. The hydrophilic or superhydrophilic regions can selective collect water on the surface.

Claims

1. A patterned surface comprising a substrate supporting a coating including polyelectrolyte multilayer, wherein the surface includes a superhydrophilic region and a superhydrophobic region.

2. The surface of claim 1, wherein the polyelectrolyte multilayer includes a superhydrophilic region.

3. The surface of claim 2, wherein the polyelectrolyte multilayer includes a superhydrophobic region.

4. The surface of claim 1, wherein the polyelectrolyte multilayer includes a nanoparticle.

5. The surface of claim 1, wherein the superhydrophobic region has a water contact angle of greater than 150°

.

6. A patterned surface comprising:

a substrate supporting a superhydrophobic coating, the superhydrophobic coating including a high-roughness polyelectrolyte multilayer, a nanometer-scale feature associated with the high-roughness polyelectrolyte multilayer, and a hydrophobic material; and

a region of reduced hydrophobicity superimposed on a predetermined region of the superhydrophobic coating.

7. The surface of claim 6, wherein the high-roughness polyelectrolyte multilayer includes a first organic polyelectrolyte.

8. The surface of claim 7, wherein the high-roughness polyelectrolyte multilayer includes a second organic polyelectrolyte.

9. The surface of claim 8, wherein the nanometer-scale feature includes a nanoparticle.

10. The surface of claim 9, wherein the hydrophobic material includes a fluoropolymer.

11. The surface of claim 10, wherein the region of reduced hydrophobicity further includes a third organic polyelectrolyte.

12. The surface of claim 11, wherein the superhydrophobic coating has an advancing water contact angle of greater than 150°

.

13. The surface of claim 12, wherein the region of reduced hydrophobicity is a hydrophilic region.

14. The surface of claim 13, wherein the region of reduced hydrophobicity is a superhydrophilic region.

15. The surface of claim 6, further comprising an antibacterial agent.

16. The surface of claim 15, wherein the antibacterial agent includes a silver nanoparticle or a quaternary amine.

17. The surface of claim 11, wherein the region of reduced hydrophobicity includes a polyelectrolyte multilayer supported by the superhydrophobic coating.

18. A method of forming a patterned surface comprising:

forming a superhydrophobic coating on a substrate; and

contacting a predetermined region of the superhydrophobic coating with a wetting agent, wherein the predetermined region is rendered less hydrophobic.

19. The method of claim 18, wherein the superhydrophobic coating includes a high-roughness polyelectrolyte multilayer, a nanometer-scale feature associated with the high-roughness polyelectrolyte multilayer, and a hydrophobic material.

20. The method of claim 19, wherein the wetting agent includes water, an organic solvent, and an electrolyte.

21. The method of claim 20, wherein the electrolyte is a polyelectrolyte.

22. The method of claim 21, wherein the polyelectrolyte includes an organic polymer.

23. The method of claim 22, wherein the polyelectrolyte includes an inorganic nanoparticle.

24. The method of claim 22, further comprising forming a polyelectrolyte multilayer in the predetermined region.

25. The method of claim 24, wherein the polyelectrolyte multilayer in the predetermined region is hydrophilic.

26. The method of claim 25, wherein the polyelectrolyte multilayer in the predetermined region is superhydrophilic.