Process for creating a polymer filament suitable for use in three-dimensional printing

Patent metadata

Field	Value
Publication number	US-11001945-B2
Application number	US-201615081048-A
Country	US
Kind code	B2
Filing date	Mar 25, 2016
Priority date	Mar 27, 2015
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

A thermoplastic filament comprising multiple polymers of differing flow temperatures in a regular geometric arrangement, and a method for producing such a filament, are described. Because of the difference in flow temperatures, there exists a temperature range at which one polymer is mechanically stable while the other is flowable. This property is extremely useful for creating thermoplastic monofilament feedstock for three-dimensionally printed parts, wherein the mechanically stable polymer enables geometric stability while the flowable polymer can fill gaps and provide strong bonding and homogenization between deposited material lines and layers. These multimaterial filaments can be produced via thermal drawing from a thermoplastic preform, which itself can be three-dimensionally printed. Furthermore, the preform can be printed with precisely controlled and complex geometries, enabling the creation of monofilament and fiber with unique decorative or functional properties.

First claim

We claim:

1. A process for creating a polymer filament suitable for use in three-dimensional printing, said process comprising:
associating a first thermoplastic polymer and a second thermoplastic polymer in a regular geometric arrangement to create a preform;
heating said preform to a drawing temperature;
pulling said preform under tension to draw said preform down to a filament such that said regular geometric arrangement is preserved
and further comprising the step of manufacturing said first thermoplastic polymer, said second thermoplastic polymer, or both by three-dimensional printing.

2. The process of claim 1 , in which said preform has a diameter of 1-1000 millimeters.

3. The process of claim 1 , wherein said filament has a filament diameter of 0.01-100 millimeters.

4. The process of claim 1 , wherein a flow temperature of said first thermoplastic polymer is 10 degrees Celsius or more higher than a flow temperature of said second thermoplastic polymer.

5. The process of claim 1 , wherein said first thermoplastic polymer is a single continuous body throughout a preform cross-section.

6. The process of claim 1 , wherein a geometry of said first thermoplastic polymer at least partially confines said second thermoplastic polymer so that said second thermoplastic polymer cannot freely release from a filament structure.

7. A process for creating a polymer filament suitable for use in three-dimensional printing, said process comprising:
associating a first thermoplastic polymer and a second thermoplastic polymer in a regular geometric arrangement to create a preform;
heating said preform to a drawing temperature;
pulling said preform under tension to draw said preform down to a filament such that said regular geometric arrangement is preserved
where said first thermoplastic polymer, said second thermoplastic polymer, or both comprise one or more of a thermoplastic material selected from the group consisting of: PLA, ABS, PC, or nylon.

8. A process for creating a polymer filament suitable for use in three-dimensional printing, said process comprising:
associating a first thermoplastic polymer and a second thermoplastic polymer in a regular geometric arrangement to create a preform;
heating said preform to a drawing temperature;
pulling said preform under tension to draw said preform down to a filament such that said regular geometric arrangement is preserved
wherein said regular geometric arrangement is a periodic geometric arrangement.

9. A process for creating a polymer filament suitable for use in three-dimensional printing, said process comprising:
associating a first thermoplastic polymer and a second thermoplastic polymer in a regular geometric arrangement to create a preform;
heating said preform to a drawing temperature;
pulling said preform under tension to draw said preform down to a filament such that said regular geometric arrangement is preserved
where at least a portion of said first thermoplastic polymer and said second thermoplastic polymer is present on an outer surface of said preform.

10. The process of claim 9 , where the proportions of the outer surface in which each polymer is present are approximately equal and spaced periodically.

11. The process of claim 1 , wherein said preform comprises a cross-sectional shape that varies non-randomly along a length of said preform.

12. A process for creating an article, said process comprising:
associating a first thermoplastic polymer and a second thermoplastic polymer in a regular geometric arrangement to create a preform;
heating said preform to a drawing temperature;
pulling said preform under tension to draw said preform down to a filament such that said regular geometric arrangement is preserved;
heating said filament to form a heated filament; and
depositing said heated filament to build a three dimensional object.

13. The process of claim 12 , further comprising subjecting said three dimensional object to a temperature sufficient for annealing to improve the physical cohesion between printed polymer lines and layers.

14. The process of claim 13 , in which said elevated temperature is lower than a flow temperature of a highest flow temperature polymer in the preform, but higher than a flow temperature of a lowest flow temperature polymer in the preform.

15. The process of claim 7 , in which said preform has a diameter of 1-1000 millimeters.

16. The process of claim 7 , wherein said filament has a filament diameter of 0.01-100 millimeters.

17. The process of claim 7 , wherein a flow temperature of said first thermoplastic polymer is 10 degrees Celsius or more higher than a flow temperature of said second thermoplastic polymer.

18. The process of claim 7 , wherein said first thermoplastic polymer is a single continuous body throughout a preform cross-section.

19. The process of claim 7 , wherein a geometry of said first thermoplastic polymer at least partially confines said second thermoplastic polymer so that said second thermoplastic polymer cannot freely release from a filament structure.

20. The process of claim 7 , wherein said preform comprises a cross-sectional shape that varies non-randomly along a length of said preform.

21. The process of claim 8 , in which said preform has a diameter of 1-1000 millimeters.

22. The process of claim 8 , wherein said filament has a filament diameter of 0.01-100 millimeters.

23. The process of claim 8 , wherein a flow temperature of said first thermoplastic polymer is 10 degrees Celsius or more higher than a flow temperature of said second thermoplastic polymer.

24. The process of claim 8 , wherein said first thermoplastic polymer is a single continuous body throughout a preform cross-section.

25. The process of claim 8 , wherein a geometry of said first thermoplastic polymer at least partially confines said second thermoplastic polymer so that said second thermoplastic polymer cannot freely release from a filament structure.

26. The process of claim 8 , wherein said preform comprises a cross-sectional shape that varies non-randomly along a length of said preform.

27. The process of claim 9 , in which said preform has a diameter of 1-1000 millimeters.

28. The process of claim 9 , wherein said filament has a filament diameter of 0.01-100 millimeters.

29. The process of claim 9 , wherein a flow temperature of said first thermoplastic polymer is 10 degrees Celsius or more higher than a flow temperature of said second thermoplastic polymer.

30. The process of claim 9 , wherein said first thermoplastic polymer is a single continuous body throughout a preform cross-section.

31. The process of claim 9 , wherein a geometry of said first thermoplastic polymer at least partially confines said second thermoplastic polymer so that said second thermoplastic polymer cannot freely release from a filament structure.

32. The process of claim 9 , wherein said preform comprises a cross-sectional shape that varies non-randomly along a length of said preform.

Assignees

• U S Army Res Laboratory Attn Rdrl Loc I
• Us Army

Inventors

• Wetzel Eric D
• Holmes Jr Larry R
• Rodriguez Ricardo X
• Toal Jr Patrick M

Classifications

• Y10T428/2975

  Tubular or cellular · CPC title

• Y10T428/2929

  Bicomponent, conjugate, composite or collateral fibers or filaments [i.e., coextruded sheath-core or side-by-side type] · CPC title

• D01F8/00 Primary

  Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B29D11/00721 Primary

  involving preforms for the manufacture of light guides · CPC title