Adhesive microstructure and method of forming same

• US 20050181170A1
• Filed: 03/14/2005
• Published: 08/18/2005
• Est. Priority Date: 05/13/2002
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Fearing, Ronald S., Setti, Metin
• Granted Patent: US 7,691,307 B2
• Time in Patent Office: Days
• US Class Current: 428/85
• CPC Class Codes: A44B 18/0003 Fastener constructions A44B18/0023, A44B18/0046 take precedence
• CPC Class Codes: A44B 18/0049 obtained by moulding processes compression moulding or articles of indefinite length characterised by the shape of the surface B29C43/222; screen moulding B29C67/08
• CPC Class Codes: A44B 18/0061 Male or hook elements A44B18/0053 takes precedence
• CPC Class Codes: B08B 1/00 Cleaning by methods involving the use of tools cleaning hollow articles by methods or apparatus specially adapted thereto B08B9/00
• CPC Class Codes: B08B 7/0028 by adhesive surfaces
• CPC Class Codes: B29C 33/42 characterised by the shape of the moulding surface, e.g. ribs or grooves
• CPC Class Codes: B29L 2031/756 Microarticles, nanoarticles
• CPC Class Codes: B81B 2203/0361 Tips, pillars
• CPC Class Codes: B81B 3/0059 Constitution or structural means for controlling the movement not provided for in groups B81B3/0037 - B81B3/0056
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C09J 2301/31 the adhesive effect being based on a Gecko structure
• CPC Class Codes: C09J 7/00 Adhesives in the form of films or foils
• CPC Class Codes: F16B 2/005 Means to increase the friction-coefficient
• CPC Class Codes: F16B 5/07 by means of multiple interengaging protrusions on the surfaces, e.g. hooks, coils,
• CPC Class Codes: Y10S 977/84 Manufacture, treatment, or detection of nanostructure
• CPC Class Codes: Y10T 24/27 including readily dissociable fastener having numerous, protruding, unitary filaments randomly interlocking with, and simultaneously moving towards, mating structure [e.g., hook-loop type fastener]
• CPC Class Codes: Y10T 24/2742 having filaments of varied shape or size on same mounting surface
• CPC Class Codes: Y10T 428/23943 Flock surface
• CPC Class Codes: Y10T 428/24008 including fastener for attaching to external surface
• CPC Class Codes: Y10T 428/24174 including sheet or component perpendicular to plane of web or sheet
• CPC Class Codes: Y10T 428/24355 : Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/28 : Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2913 : Rod, strand, filament or fiber
• CPC Class Codes: Y10T 428/2973 : Particular cross section
• CPC Class Codes: Y10T 428/2976 : Longitudinally varying
• CPC Class Codes: Y10T 428/2978 : Surface characteristic
• CPC Class Codes: Y10T 428/298 : Physical dimension

Abstract

A fabricated microstructure comprising at least one protrusion capable of providing an adhesive force at a surface of between about 60 and 2,000 nano-Newtons. A stalk supports the protrusion at an oblique angle relative to a supporting surface. The microstructure can adhere to different surfaces.

Claims

1-29. -29. (canceled)

30. A method of fabricating an adhesive microstructure comprising:

molding a structure having shafts supporting a plurality of stalks at an oblique angle;

removing said structure to provide a template;

molding the template with a polymer; and

separating the template from the polymer to form the microstructure.

31. The method of claim 30 wherein the shafts comprise micro-scale, high aspect ratio members and the stalks comprise nano-scale, high aspect ratio members.

32. The method of claim 30 wherein the polymer is a liquid polymer or a sputtered polymer.

33. A method of fabricating an adhesive microstructure comprising:

joining a first template having a first set of pores that have a first diameter and that are at an oblique angle relative to a surface of the first template to a second template having a second set of pores that have a second diameter less than the first diameter, the second set of pores forming an oblique angle relative to said first set of pores;

molding the first and second templates; and

removing the templates to form the microstructure.

34. The method of claim 33 wherein the first set of pores have a diameter between about 1 and 10 microns, and a length between about 1 and 500 microns, and wherein the second set of pores have a diameter between about 50 nanometers and 2.0 microns, and a length between about 0.50 and 20 microns.

35. The method of claim 33 wherein the first and second templates are molded with a polymer.

36. The method of claim 33 wherein the first and second templates are joined by bonding.

37. A method of fabricating an adhesive microstructure comprising:

self-assembling a nano-pore array including two different polymers; and

shearing the array and removing one of the polymers to form a microstructure having an array of stalks with the stalks able to support at least one protrusion at an oblique

angle wherein the protrusion provides an adhesive force at a surface by intermolecular forces.