Patterned electrospinning

• US 20050104258A1
• Filed: 10/18/2004
• Published: 05/19/2005
• Est. Priority Date: 07/02/2003
• Status: Abandoned Application

• Current Assignee: Physical Sciences Incorporated
• Original Assignee: Physical Sciences Incorporated
• Inventors: Lennhoff, John D.
• Application Number:
  US10/967,627
• Publication Number:
  US 20050104258A1
• Time in Patent Office: Days
• US Class Current: 264/465
• CPC Class Codes: D01D 5/0076 characterised by the collecting device, e.g. drum, wheel, endless belt, plate or grid D01D5/0046 takes precedence
• CPC Class Codes: D01D 5/0084 Coating by electro-spinning, i.e. the electro-spun fibres are not removed from the collecting device but remain integral with it, e.g. coating of prostheses
• CPC Class Codes: D01D 5/0092 characterised by the electrical field, e.g. combined with a magnetic fields, using biased or alternating fields

Abstract

A polymer is directed from a source electrode into an electric field that drives the formation of electrospun fibers that are deposited onto a collecting surface to thereby form a patterned polymer structure. The collecting surface can be a counterelectrode or a collecting surface that is between the source electrode and a counterelectrode. Apparatus employed to conduct the method include an electrospinning source that directs polymer into an electric field formed by source and counterelectrodes. A collecting surface, such as the counterelectrode or a surface interposed between the source and counterelectrodes, collects electrospun fibers. Articles of manufacture formed by the method of apparatus include, for example, a structure of patterned electrospun fibers comprising multiple aggregations of polymeric electrospun fibers.

Claims

1. A method for forming a patterned polymer structure, comprising the step of directing a polymer from a source electrode into an electric field that drives the polymer to form electrospun fibers and deposits the electrospun fibers onto a collecting surface in a pattern, thereby forming a patterned polymer structure.

2. The method of claim 1 wherein the electrospun fibers are deposited onto a collecting surface that is a counterelectrode.

3. The method of claim 1 wherein the electrospun fibers are deposited onto a collecting surface that is between the source electrode and a counterelectrode.

4. The method of claim 3 wherein the electrospun fibers are deposited onto a portion of the collecting surface.

5. The method of claim 3 wherein the counterelectrode forms a pattern of electric charge and the electrospun fibers are deposited on the collecting surface as the patterned structure.

6. The method of claim 1 wherein the patterned structure is formed by moving either or both the electric charge and the collecting surface relative to each other.

7. The method of claim 6 wherein the relative movement is intermittent.

8. The method of claim 6 wherein the relative movement is continuous.

9. The method of claim 4 wherein field lines of the electric field intersect the collecting surface and the electrospun fibers are deposited on the portion of the collecting surface at which the field lines intersect the collecting surface, whereby the patterned structure is formed.

10. The method of claim 9 further comprising moving the counterelectrode whereby the intersection of the field lines with the collecting surface is changed in relationship to the movements.

11. The method of claim 10 further comprising moving multiple counterelectrodes.

12. The method of claim 9 further comprising moving the collecting surface, whereby the intersection of the field lines with the collecting surface is changed in relationship to the movements.

13. The method of claim 4 wherein field lines of the electric field form an array of concentrations of electric charge at the collecting surface, whereby the electrospun fibers are deposited as a patterned structure that includes an array of aggregations of electrospun fibers.

16. The method of claim 12 wherein the collecting surface is interposed by moving the collecting surface in the electric field in a direction that is essentially parallel to the plane.

29. An article of manufacture produced by the method of claim 1.

14. A method for forming a patterned structure of electrospun fibers, comprising the steps of:

(a) electrically directing fiber-forming polymeric material from a spinning source in an electric field created by source and counterelectrodes, the counterelectrode forming concentrations of electrical charges which include a patterned array in a plane that traverses the electric field; and

(b) interposing a collecting surface at the plane, whereby the directed fibers are deposited on the collecting surface in aggregations that are essentially the same pattern as formed by the concentrations of electrical charge.

15. The method of claim 14 wherein the concentrations of electrical charge an moved to form the patterned array.

17. A method for forming a patterned structure of electrospun fibers, comprising the steps of directing a polymer stream into an electric field created by source and counterelectrodes, the electric field including a pattern of electric charge at a collecting surface between the source and counterelectrodes, whereby the polymer stream splays to form electrospun fibers that deposit onto the collecting surface as a structure having the pattern of electric charge at the collecting surface.

18. Apparatus for forming a patterned array of electrospun fibers, comprising:

(a) means for electrically directing fibers from a spinning source in an electric field created by one or more source and counterelectrodes, the one or more counterelectrodes producing at least one concentration of electrical charge; and

(b) a collecting surface between the source and counterelectrodes.

19. The apparatus of claim 18 wherein the means for electrically directing fibers is movable relative to the collecting surface.

20. The apparatus of claim 18 wherein the means for electrically directing fibers moves the one or more counterelectrodes such that the movements of the concentration of electrical charge form a structure in essentially the same pattern as the pattern formed by the movements of the concentrations of electric charge.

21. The apparatus of claim 18 wherein each of the concentrations of electrical charges is essentially circular.

22. Apparatus of claim 18 wherein the means for electrically directing electrospinning fibers comprises one or more counterelectrodes, the concentration of electrical charge of which form a patterned array.

23. Apparatus of claim 18 wherein the collecting surface is polymeric film.

24. Apparatus of claim 18 further comprising means to move the collecting surface.

25. An article of manufacture, comprising multiple aggregations of polymeric electrospun fibers defining at least one area between the aggregations.

26. The article of manufacture of claim 25 further comprising a planar member upon which the multiple aggregations are positioned, thereby forming a composite structure.

27. The article of manufacture of claim 25 wherein the planar material is a film.

28. The article of manufacture of claim 25 wherein the electrospun fibers include multiple essentially circular aggregations.