Methods and devices for thickness-limited electrospray additive manufacturing

Patent metadata

Field	Value
Publication number	US-12427717-B2
Application number	US-202017595341-A
Country	US
Kind code	B2
Filing date	May 15, 2020
Priority date	May 15, 2019
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

A method for simultaneous additive manufacturing and thickness-limited, electrospray deposition may include forming an electrically conductive target via additive manufacturing and exposing the electrically conductive target to an incident spray comprising a thermo-responsive polymer solution, in the presence of an electric field. The electrically conductive target may have a surface temperature, the thermo-responsive polymer solution may have a solution temperature, and the thermo-responsive polymer solution may include a non-conductive polymer. The method may further include allowing the solution temperature to deviate toward the surface temperature to a deposited temperature at which the non-conductive polymer is immobile. The method may further include allowing the non-conductive polymer to accumulate on the electrically conductive target to form a layer, having a thickness sufficient to repulse the incident spray.

First claim

What is claimed is:

1. A method of additive manufacturing and thickness-limited, electrospray deposition comprising:
ejecting an electrically conductive target, comprising an additive manufacturing material, from an additive manufacturing device;
exposing a first portion of the electrically conductive target to a first incident spray comprising a thermo-responsive polymer solution, in the presence of an electric field,
receiving, at a computing device, first data from one or more components configured to measure a parameter of the ejecting;
receiving, at the computing device, second data from one or more components configured to measure a parameter of the exposing;
wherein the electrically conductive target has a surface temperature,
wherein the thermo-responsive polymer solution comprises a non-conductive polymer,
wherein the thermo-responsive polymer solution has a solution temperature;

allowing the solution temperature to deviate toward the surface temperature to a deposited temperature at which the non-conductive polymer is immobile; and
wherein the computing device is configured to use the first data and the second data to control one or more parameters of the ejecting and the exposing to allow the non-conductive polymer to accumulate on the electrically conductive target to form a layer, having a thickness sufficient to repulse the first incident spray.

2. The method according to claim 1 , wherein the steps of ejecting the electrically conductive target and exposing the electrically conductive target to the incident spray are performed simultaneously.

3. The method according to claim 1 , wherein the layer has a spherical shell surface morphology.

4. The method according to claim 3 , wherein the spherical shell surface morphology comprises a plurality of spheroidal particles comprising the non-conductive polymer, wherein each of the plurality of spheroidal particles has at least one dimension less than 100 micrometers.

5. The method according to claim 1 , wherein the layer has a nanowire surface morphology.

6. The method according to claim 5 , wherein the nanowire surface morphology comprises a plurality of elongated strands comprising the non-conductive polymer, wherein each of the plurality of elongated strands has at least one dimension less than 100 micrometers.

7. The method according to claim 1 , wherein the thermo-responsive polymer solution further comprises a plurality of filler particles.

8. The method according to claim 7 , wherein the filler particles are conductive filler particles, and wherein the method further comprises thermally densifying the layer to at least partially remove the non-conductive polymer to form a continuous network of the conductive filler particles.

9. The method according to claim 7 , wherein the layer has a particle volume content of from about 50 to about 99 percent.

10. The method according to claim 7 , wherein each of the plurality of filler particles has at least one dimension less than 10 micrometers.

11. The method according to claim 1 , wherein, when the electrically conductive target is exposed to an incident spray consisting of any individual component of the thermo-responsive polymer solution, in the presence of an electric field, a film surface charge produced by deposition of any individual component of the thermo-responsive polymer solution is not able to accumulate on the electrically conductive target sufficiently to allow formation of a layer, having a thickness sufficient to repulse the incident spray.

12. The method according to claim 1 where the thickness of the layer is between 100 nm and 100 μm.

13. The method according to claim 1 , further comprising exposing, in the presence of the electric field, a second portion of the electrically conductive target to a second incident spray, the second incident spray having a different composition than the first incident spray, the second incident spray comprising a second thermo-responsive polymer solution.

14. The method according to claim 13 where a transition between the first and second spray occurs over a region of 100 nm to 100 μm.

15. The method according to claim 13 where a transition between the first and second spray occurs continuously from the thermo-responsive polymer solution of the first incident spray to the second thermo-responsive polymer solution of the second incident spray.

16. The method according to claim 15 where the transition from the thermo-responsive polymer solution of the first incident spray to the second thermo-responsive polymer solution of the second incident spray is created by microfluidic mixing.

17. An apparatus comprising an additive manufacturing device, a spraying device, and a computing device programmed to control the additive manufacturing device and the spraying device to perform a method of additive manufacturing and thickness-limited, electrospray deposition, the method comprising:
ejecting an electrically conductive target, comprising an additive manufacturing material, from the additive manufacturing device;
exposing a first portion of the electrically conductive target to a first incident spray from the spraying device, the first incident spray comprising a thermo-responsive polymer solution, in the presence of an electric field,
receiving, at the computing device, first data from one or more components configured to measure a parameter of the ejecting;
receiving, at the computing device, second data from one or more components configured to measure a parameter of the exposing;
wherein the electrically conductive target has a surface temperature,
wherein the thermo-responsive polymer solution comprises a non-conductive filler particle or polymer,
wherein the thermo-responsive polymer solution has a solution temperature;

allowing the solution temperature to deviate toward the surface temperature to a deposited temperature at which the non-conductive polymer is immobile; and
wherein the computing device is configured to use the first data and the second data to control one or more parameters of the ejecting and the exposing to allow the non-conductive polymer to accumulate on the electrically conductive target to form a layer, having a thickness sufficient to repulse the first incident spray.

18. The apparatus according to claim 17 , wherein the one or more components configured to measure the parameter of the exposing comprises one selected from a group consisting of:
a spray flowrate meter adapted to measure and optionally to record a flowrate of a spray material ejected from the spraying device,
a spray conditioner adapted to control the temperature of the spray material ejected from the spraying device,
a spray current meter adapted to measure and optionally to record a current of the spray material ejected from the spraying device,
a spray flowrate controller adapted to control a flowrate of the spray material ejected from the spraying device,
a spray voltage meter adapted to measure optionally to record voltage of the spray material ejected from the spraying device, and
a spray voltage controller adapted to control the voltage of the spray material ejected from the spraying device,
a focusing ring held at a voltage of the same polarity as the spray material,
a first spray current monitor to monitor a current of the spray material arriving at the printed material,
a second spray current monitor to monitor a current of the spray material arriving at a secondary target,
a camera to monitor stability of the spray,
wherein the one or more components configure

Assignees

• Univ Rutgers

Inventors

• Singer Jonathan P
• Lee Howon

Classifications

• B05D1/04

  involving the use of an electrostatic field {(B05D1/025 and B05D1/14 take precedence)} · CPC title

• B05B5/0255 Primary

  spraying and depositing by electrostatic forces only · CPC title

• B33Y70/00

  Materials specially adapted for additive manufacturing · CPC title

• B33Y30/00

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title