Manufacturing process, such as three-dimensional printing, including solvent vapor filming and the like

• US 7,815,826 B2
• Filed: 05/12/2005
• Issued: 10/19/2010
• Est. Priority Date: 05/12/2004
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Sachs, Emanuel M., Serdy, James G.
• Primary Examiner(s): Theisen; Mary Lynn F
• Application Number:
  US11/579,783
• Publication Number:
  US 20080032083A1
• Time in Patent Office: 1,986 Days
• Field of Search: None
• US Class Current: 264/49
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30225 Flat cylinders, i.e. discs
• CPC Class Codes: A61F 2002/30785 parallel
• CPC Class Codes: A61F 2002/30985 using three dimensional printing [3DP]
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00353 Bone cement, e.g. polymethylmethacrylate or PMMA
• CPC Class Codes: A61L 2300/412 Tissue-regenerating or healing or proliferative agents
• CPC Class Codes: A61L 2300/434 of enzymes
• CPC Class Codes: A61L 2300/602 Type of release, e.g. controlled, sustained, slow
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: Y10T 428/15 Sheet, web, or layer weakened to permit separation through thickness
• CPC Class Codes: Y10T 428/24273 including aperture
• CPC Class Codes: Y10T 428/31504 : Composite [nonstructural laminate]

Abstract

Methods of manufacturing an article use three-dimensional printing for a portion of the manufacturing. Three-dimensionally printing is conducted onto a powder bed which contains both organic-solvent-soluble, water-insoluble particles and water soluble, organic-solvent-insoluble particles. The water-soluble particles which may be selected for properties such as size and may include more than one substance. The organic-solvent-insoluble particles may further include at least one substantially insoluble substance such as a member of the calcium phosphate family. Printing may be done using an aqueous binder liquid. After removal of unbound powder, the preform may be exposed to the vapor of an organic solvent which causes the particles of organic-soluble-polymer to fuse to each other. This may further be followed by dissolving out the water-soluble particles, if such particles were present in the powder. Solvent vapor fusing together with the use of porogen particles may also be used in manufacturing methods other than 3DP. Rather than using organic solvent, heat responsive particles can be used, and can be filmed by elevated temperatures. Articles that may be produced by the described methods exhibit features such as a high porosity and an ability to undergo large deformations without breaking, and by at least partial springback from such deformation. The springback may be substantially instantaneous or may be time-dependent involving a time period of at least several seconds.

Claims

1. A method of fabricating an article of manufacture, the method comprising:

a. forming at least one particle mixture by mixing particles of an organic-solvent-soluble, water-insoluble material and particles of a water-soluble, organic-solvent-insoluble material;

b. manufacturing an article by causing particles of the water-soluble, organic-solvent-insoluble material in the particle mixture to bind to other particles of the water-soluble, organic-solvent-insoluble material to form a water-soluble, organic-solvent-insoluble structure that also binds particles of the organic-solvent-soluble, water-insoluble material;

c. forming a film of the organic-solvent-soluble, water-insoluble material by causing particles of the organic-solvent-soluble, water-insoluble material to soften and at least partially flow to form a film adjacent to surfaces of the water-soluble, organic-solvent-insoluble material; and

d. providing conditions such that the organic-solvent-soluble, water-insoluble material hardens.

2. The method of claim 1, the step of forming a film comprising forming a film of the organic-solvent-soluble, water-insoluble material that substantially conforms to surfaces of the water-soluble, organic-solvent-insoluble material.

3. The method of claim 1, further wherein the step of causing particles of the water-soluble, organic-solvent-insoluble material in the particle mixture to bind to other particles of the water-soluble, organic-solvent-insoluble material comprises contacting the particle mixture with an aqueous solution of a water-soluble, organic-solvent-insoluble material.

4. The method of claim 1, further comprising, after the filming of the organic-solvent-soluble, water-insoluble material, exposing the article to water under conditions suitable to dissolve at least some of the water-soluble, organic-solvent-insoluble structure.

5. The method of claim 1, wherein the water-soluble, organic-solvent-insoluble material comprises at least one substance selected from the group consisting of salts and sugars.

6. The method of claim 1, wherein the water-soluble, organic-solvent-insoluble material comprises at least one substance selected from the group consisting of sodium chloride, sucrose, fructose and lactose.

7. The method of claim 1, wherein the water-soluble, organic-solvent-insoluble material comprises a substance having a relatively higher rate of dissolution in water and a substance having a relatively lower rate of dissolution in water.

8. The method of claim 7, further wherein the relatively higher dissolution rate substance has a rate of dissolution in water, by weight at room temperature, which is at least two times a rate of dissolution in water, by weight at room temperature, of the relatively lower dissolution rate substance.

9. The method of claim 7, wherein the relatively lower dissolution rate substance is present in the particle mixture in particle sizes that correspond to a specified pore size in the article.

10. The method of claim 7, wherein the relatively higher dissolution rate substance is present in the particle mixture in particle sizes which are generally smaller than particle sizes of the relatively lower dissolution rate substance.

11. The method of claim 1, wherein forming the particle mixture comprises mixing particles of an organic-solvent-soluble, water-insoluble material, and particles of a water-soluble, organic-solvent-insoluble material, and particles of a substantially insoluble material.

12. The method of claim 11, wherein the particles of substantially insoluble material comprise a compound that comprises calcium and a group containing phosphorus and oxygen.

13. The method of claim 1, wherein the step of fabricating the article comprises molding the particle mixture to cause particles of the water-soluble, organic-solvent-insoluble material to bind to other particles of the water-soluble, organic-solvent-insoluble material.

14. The method of claim 1, wherein manufacturing the article comprises:

a. depositing a layer of particles comprising the particle mixture;

b. depositing onto the layer of particles in selected places an aqueous liquid suitable to cause particles of the water-soluble, organic-solvent-insoluble material to bind to other particles of the water-soluble, organic-solvent-insoluble material;

c. repeating the above steps a and b as many times as needed to create a shape; and

d. removing unbound particles.

15. The method of claim 14, wherein depositing the aqueous liquid comprises depositing water.

16. The method of claim 14, wherein depositing the aqueous liquid comprises depositing a solution of a binder substance in water.

17. The method of claim 14, wherein depositing the aqueous liquid comprises depositing a solution of the water-soluble, organic-solvent-insoluble material.

18. The method of claim 14, wherein depositing the aqueous liquid comprises depositing the aqueous liquid at a saturation parameter of less than approximately 20%.

19. The method of claim 14, wherein depositing the aqueous liquid comprises depositing the aqueous liquid at a saturation parameter of less than approximately 50%.

20. The method of claim 14, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture that comprises a first composition of organic-solvent-soluble, water-insoluble material and further comprises depositing a layer of a second particle mixture that comprises a second composition of organic-solvent-soluble, water-insoluble material.

21. The method of claim 14, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture which comprises a substantially insoluble material and also depositing a layer of a second particle mixture which is free of any substantially insoluble material.

22. The method of claim 14, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture which comprises a first composition of water-soluble, organic-solvent-insoluble material, and also depositing a layer of a second particle mixture which comprises a second composition of water-soluble, organic-solvent-insoluble material.

23. The method of claim 14, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture which comprises a first average particle size, and depositing a layer of a second particle mixture which comprises a second average particle size.

24. The method of claim 1, wherein the organic-solvent-soluble, water-insoluble material comprises a polymer or copolymer.

25. The method of claim 1, wherein the organic-solvent-soluble, water-insoluble material comprises a substance selected from the group consisting of:

polycaprolactone, members of the poly lactic co-glycolic acid family, polymethyl methacrylate, and comb polymers.

26. The method of claim 1, wherein forming the film of the organic-solvent-soluble, water-insoluble material comprises exposing the article to a vapor of an organic solvent in which the organic-solvent-soluble, water-insoluble material is soluble, under suitable conditions and for a suitable duration to cause organic-solvent-soluble, water-insoluble material in the article to soften and form a film.

27. The method of claim 26, wherein exposing the article to the vapor of an organic solvent comprises exposing the article to the vapor of a halogenated hydrocarbon.

28. The method of claim 26, wherein exposing the article to the vapor of an organic solvent comprises exposing the article to the vapor of chloroform.

29. The method of claim 1, wherein causing the organic-solvent-soluble, water-insoluble material to flow comprises exposing it to an organic solvent, and providing conditions such that the organic-solvent-soluble, water-insoluble material hardens comprises causing enough of the organic solvent to escape from the organic-solvent-soluble, water-insoluble material so that the organic-solvent-soluble, water-insoluble material hardens.

30. The method of claim 1, wherein the forming the film of the organic-solvent-soluble, water-insoluble material comprises heating the article to a suitable temperature for a suitable duration to cause organic-solvent-soluble, water-insoluble material in the article to soften and form a film.

49. The method of claim 18, the step of establishing the first condition comprising contacting water with the particle mixture, and the step of establishing the second condition comprising heating the particle mixture including the bound particles of the first material to a temperature at which the particles of the second material form a film bound to the particles of the first material.

31. A method of fabricating an article of manufacture, comprising the steps of:

a. depositing a layer of particles comprising a particle mixture of particles of an organic-solvent-soluble, water-insoluble material and particles of a water-soluble, organic-solvent-insoluble material;

b. depositing onto the layer of particles in selected places an aqueous liquid suitable to cause particles of the water-soluble, organic-solvent-insoluble material to bind to other particles of the water-soluble, organic-solvent-insoluble material, thereby causing particles of the water-soluble, organic-solvent-insoluble material to bind to other particles of the water-soluble, organic-solvent-insoluble material to form a water-soluble, organic-solvent-insoluble structure that also binds particles of the organic-solvent-soluble, water-insoluble material;

c. repeating the above steps a and b to create a shape;

d. removing unbound particles;

e. forming a film of the organic-solvent-soluble, water-insoluble material by causing particles of the organic-solvent-soluble, water-insoluble material to soften and at least partially flow to form a film adjacent to surfaces of the water-soluble, organic-solvent-insoluble material; and

f. providing conditions such that the film of organic-solvent-soluble, water-insoluble material hardens.

32. The method of claim 31, wherein the step of depositing aqueous liquid comprises depositing water.

33. The method of claim 31, wherein depositing the aqueous liquid comprises depositing a solution of a binder substance in water.

34. The method of claim 31, wherein depositing the aqueous liquid comprises depositing the aqueous liquid at a saturation parameter of less than approximately 20%.

35. The method of claim 31, wherein depositing the aqueous liquid comprises depositing the aqueous liquid at a saturation parameter of less than approximately 50%.

36. The method of claim 31, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture that comprises a first composition of organic-solvent-soluble, water-insoluble material and further comprises depositing a layer of a second particle mixture that comprises a second composition of organic-solvent-soluble, water-insoluble material.

37. The method of claim 31, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture which comprises a substantially insoluble material and also depositing a layer a second particle mixture which is free of any substantially insoluble material.

38. The method of claim 31, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture which comprises a first composition of water-soluble, organic-solvent-insoluble material, and also depositing a layer of a second particle mixture which comprises a second composition of water-soluble, organic-solvent-insoluble material.

39. The method of claim 31, wherein depositing the layers of particles comprises depositing a layer of a first particle mixture which comprises a first average particle size, and depositing a layer of a second particle mixture which comprises a second average particle size.

40. A method of fabricating an article of manufacture, the method comprising:

a. forming at least one particle mixture by mixing particles of water-insoluble material having a relatively low softening temperature and particles of a water-soluble material having a relatively higher softening temperature;

b. manufacturing an article by causing particles of the water-soluble material in the particle mixture to adhere to other particles of the water-soluble material to form a water-soluble structure that also holds particles of the water-insoluble material;

c. forming a film of the water-insoluble material by heating the water-soluble structure to a temperature sufficient to causing particles of the water-insoluble material to soften and at least partially flow to form a film adjacent to surfaces of the water-soluble material, at a temperature below that which would cause particles of the water-soluble material to soften and flow; and

d. providing conditions such that the water-insoluble material hardens.

41. The method of claim 40, further comprising the step of applying water to the water-soluble structure, so that the water-soluble particles dissolve into the water, leaving a water-insoluble film adjacent to locations previously occupied by water soluble particles.

42. A method of fabricating an article of manufacture, the method comprising:

a. forming at least one particle mixture by mixing particles of first material that is responsive to a first condition by binding with adjacent particles of the first material and not responsive to a second condition, and particles of a second material that is responsive to the second condition by filming with adjacent particles of the second material and not responsive to the first condition;

b. manufacturing an article by establishing the first condition, thereby causing particles of the first material in the particle mixture to bind to other particles of the first material to form a structure that is responsive to the first condition and that also binds particles of the second material;

c. establishing the second condition, thereby forming a film of the second material by causing particles of the second material to soften and at least partially flow to form a film adjacent to surfaces of the particles of the first material, while particles of the first material remain bound to each other; and

d. providing conditions such that the film formed from particles of the second material hardens.

43. The method of claim 42, further comprising the step of establishing again the first condition to the bound structure of particles of the first material, so that the first material particles separate from each other and from the film formed from the particles of the second material, leaving a film adjacent to locations previously occupied by particles of the first material.

44. The method of claim 42, further comprising the step of establishing a third condition to the bound structure of particles of the first material, the particles of the first material being responsive to the third condition and the particles of the second material not being responsive to the third condition, so that the first material particles separate from each other and from the film formed from the particles of the second material, leaving a film adjacent to locations previously occupied by particles of the first material.

45. The method of claim 42, the particles of the first material comprising organic-solvent-soluble, water-insoluble material and the particles of the second material comprising water-soluble, organic-solvent-insoluble material.

46. The method of claim 42, the particles of the first material comprising first-solvent-soluble-second-solvent-insoluble material and the particles of the second material comprising second-solvent-soluble-first-solvent-insoluble material.

47. The method of claim 46, the step of establishing the first condition comprising contacting the first solvent in liquid form with the particle mixture, and the step of establishing the second condition comprising contacting the second solvent in vapor form with the particle mixture including the adhered particles of the first material.

48. The method of claim 42, the particles of the first material comprising water-soluble, high-melting-temperature material and the particles of the second material comprising low-melting-temperature, water-insoluble material.