Engineering-grade consumable materials for electrophotography-based additive manufacturing system

• US 10,061,221 B2
• Filed: 11/29/2016
• Issued: 08/28/2018
• Est. Priority Date: 07/17/2013
• Status: Active Grant

• Current Assignee: Evolve Additive Solutions, Inc.
• Original Assignee: Evolve Additive Solutions, Inc.
• Inventors: Orrock, James E., Chillscyzn, Steven A., Martin, Trevor I.
• Primary Examiner(s): Rodee, Christopher D
• Application Number:
  US15/363,453
• Publication Number:
  US 20170075245A1
• Time in Patent Office: 637 Days
• CPC Class Codes: B29C 43/006 Pressing and sintering powders, granules or fibres
• CPC Class Codes: B29C 64/153 using layers of powder being selectively joined, e.g. by selective laser sintering or melting
• CPC Class Codes: B29C 67/24 characterised by the choice of material
• CPC Class Codes: B29K 2077/00 Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/0005 containing compounding ingredients releasing, lubricating or separating agents B29C33/56, fibers B29K2105/08, B29K2105/12; fillers B29K2105/16, recycled material B29K2105/26
• CPC Class Codes: B29K 2105/0023 improving electric conduction
• CPC Class Codes: B29K 2105/005 Heat sensitisers or absorbers
• CPC Class Codes: B29K 2105/251 Particles, powder or granules expandable particles B29K2105/046
• CPC Class Codes: B29K 2995/0094 Geometrical properties
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: G03G 13/08 using a solid developer, e.g. powder developer
• CPC Class Codes: G03G 13/16 of a toner pattern, e.g. a powder pattern
• CPC Class Codes: G03G 13/20 Fixing, e.g. by using heat
• CPC Class Codes: G03G 13/22 Processes involving a combination of more than one step according to groups G03G13/02 - G03G13/20 G03G13/01 takes precedence
• CPC Class Codes: G03G 15/08 using a solid developer, e.g. powder developer
• CPC Class Codes: G03G 15/1625 on a base other than paper
• CPC Class Codes: G03G 15/224 Machines for forming tactile or three dimensional images by electrographic means, e.g. braille, 3d printing
• CPC Class Codes: G03G 15/24 whereby at least two steps are performed simultaneously
• CPC Class Codes: G03G 2215/1695 at the second or higher order transfer point
• CPC Class Codes: G03G 9/0819 characterised by the dimensions of the particles
• CPC Class Codes: G03G 9/08757 : Polycarbonates
• CPC Class Codes: G03G 9/08764 : Polyureas; Polyurethanes
• CPC Class Codes: G03G 9/08766 : Polyamides, e.g. polyesteramides
• CPC Class Codes: G03G 9/08795 : characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants
• CPC Class Codes: G03G 9/08797 : characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature
• CPC Class Codes: G03G 9/09783 : Organo-metallic compounds
• CPC Class Codes: G03G 9/09791 : Metallic soaps of higher carboxylic acids

Abstract

A method of printing three-dimensional parts with an electrophotography-based additive manufacturing system, with a part material including a composition having an engineering-grade thermoplastic material and a charge control agent. The part material is provided in a powder form having a controlled particle size, and is configured for use in the electrophotography-based additive manufacturing system having a layer transfusion assembly for printing the three-dimensional parts in a layer-by-layer manner.

Claims

1. A method for printing a three-dimensional part with an electrophotography-based additive manufacturing system having an electrophotography engine, a transfer medium, and a layer transfusion assembly, the method comprising:

providing a part material to the electrophotography-based additive manufacturing system, the part material compositionally comprising a charge control agent, and a thermoplastic material having a heat deflection temperature ranging from about 100°

C. to about 150°

C., wherein the thermoplastic material comprises polycarpolactum (PA6), polyhexamethyleneadipamide (PA6,6), polyhexamethylenenonamide (PA6,9), polyhexamethylenesebacamide (PA6,10), polyamide 6/12 (PA6,12), polyenantholactum (PA7), polyundecanolactum (PA11), polylaurolactam (PA12), or mixtures thereof and has a powder form having a D90/D50 particle size distribution and a D50/D10 particle size distribution each ranging from about 1.00 to about 1.40, and wherein the D90/D50 particle size distribution and the D50/D10 particle size distribution are within about 10% of each other;

triboelectrically charging the part material to a Q/M ratio having a negative charge or a positive charge, and a magnitude ranging from about 5 micro-Coulombs/gram to about 50 micro-Coulombs/gram;

developing layers of the three-dimensional part from the charged part material with the electrophotography engine;

electrostatically attracting the developed layers from the electrophotography engine to the transfer medium;

moving the attracted layers to the layer transfusion assembly with the transfer medium; and

transfusing the moved layers to previously-printed layers of the three-dimensional part with the layer transfusion assembly.

2. The method of claim 1, wherein the powder form of the part material has a D50 particle size ranging from about 5 micrometers to about 30 micrometers.

3. The method of claim 1, wherein the part material further comprises a heat absorber, wherein the charge control agent constitutes from about 0.1% by weight to about 5% by weight of the part material, and wherein the heat absorber constitutes from about 0.5% by weight to about 10% by weight of the part material.

4. The method of claim 1, wherein the part material further comprises a flow control agent constituting from about 0.1% by weight to about 10% by weight of the part material.

5. The method of claim 1, wherein the polyamide comprises PA6;

PA6,6;

PA6,12;

PA11;

polylaurolactam (PA12), or mixtures thereof.

6. The method of claim 1, wherein providing a part material to the electrophotography-based additive manufacturing system comprises providing an interchangeable cartridge to the electrophotography-based additive manufacturing system, wherein the interchangeable cartridge comprises a supply of the part material.

7. The method of claim 1, wherein triboelectrically charging the part material comprises mixing the part material with carrier particles.

8. The method of claim 1, and further comprising:

electrostatically attracting developed layers of a support material to the transfer medium;

moving the attracted layers of the support material to the layer transfusion assembly along with the attracted layers of the part material; and

transfusing the moved layers of the support material along with the moved layers of the part material with the layer transfusion assembly.

9. A method for printing a three-dimensional part with an electrophotography-based additive manufacturing system having an electrophotography engine, a transfer medium, and a layer transfusion assembly, the method comprising:

providing a part material to the electrophotography-based additive manufacturing system, the part material compositionally comprising a charge control agent, and a thermoplastic material having a heat deflection temperature ranging from about 100°

C. to about 150°

C., wherein the thermoplastic material comprises polycarpolactum (PA6), polyhexamethyleneadipamide (PA6,6), polyhexamethylenenonamide (PA6,9), polyhexamethylenesebacamide (PA6,10), polyamide 6/12 (PA6,12), polyenantholactum (PA7), polyundecanolactum (PA11), polylaurolactam (PA12), or mixtures thereof and has a powder form having a D90/D50 particle size distribution and a D50/D10 particle size distribution each ranging from about 1.00 to about 1.40 and wherein the D90/D50 particle size distribution and the D50/D10 particle size distribution are within about 10% of each other;

triboelectrically charging the part material to a Q/M ratio having a negative charge or a positive charge, and a magnitude ranging from about 5 micro-Coulombs/gram to about 50 micro-Coulombs/gram;

developing a layer of the three-dimensional part from the charged part material with the electrophotography engine;

electrostatically attracting the developed layer from the electrophotography engine to the transfer medium;

moving the attracted layers to the layer transfusion assembly with the transfer medium;

heating the developed layer on the transfer medium to a temperature that exceeds the glass transition temperature of the part material; and

transfusing the heated layer to previously-printed layers of the three-dimensional part with pressure over time with a nip roller.

10. The method of claim 9, wherein the powder form of the part material has a D50 particle size ranging from about 5 micrometers to about 30 micrometers.

11. The method of claim 9, wherein the part material further comprises a heat absorber, wherein the charge control agent constitutes from about 0.1% by weight to about 5% by weight of the part material, and wherein the heat absorber constitutes from about 0.5% by weight to about 10% by weight of the part material.

12. The method of claim 9, wherein the part material further comprises a flow control agent constituting from about 0.1% by weight to about 10% by weight of the part material.

13. The method of claim 9, wherein the polyamide comprises PA6;

PA6,6;

PA6,12;

PA11;

polylaurolactam (PA12), or mixtures thereof.

14. The method of claim 9, wherein providing a part material to the electrophotography-based additive manufacturing system comprises providing an interchangeable cartridge to the electrophotography-based additive manufacturing system, wherein the interchangeable cartridge comprises a supply of the part material.

15. The method of claim 9, wherein triboelectrically charging the part material comprises mixing the part material with carrier particles.

16. The method of claim 9, and further comprising:

developing, electrostatically attracting, moving, heating and transfusing additional layers to form a stack of layers until the three-dimensional part is printed.