Catalyst ink for three-dimensional conductive constructs

Patent metadata

Field	Value
Publication number	US-10619059-B1
Application number	US-201916447277-A
Country	US
Kind code	B1
Filing date	Jun 20, 2019
Priority date	Jun 20, 2019
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

A method of constructing conductive material in arbitrary three-dimensional (3D) geometries, such as 3D printing. The method may include selective application of an aerosol-based colloidal solution containing a catalytic palladium nanoparticle material onto a substrate and then immersion of the coated substrate into an electro-less plating bath for deposition of conductive copper material. The above steps may be repeated to create arbitrary 3D geometric constructs containing conductive metallic patterns.

First claim

We claim:

1. A method of forming a three-dimensional construct comprising
i. preparing a catalyst ink comprising a colloidal solution comprising a solvent and palladium nanoparticles; and
ii. depositing the catalyst ink from step (i) onto a surface of a substrate using aerosol jet printing;
iii. subjecting the substrate to electro-less plating to plate the palladium nanoparticles with copper; and
iv. repeating steps ii and iii until the three-dimensional construct is formed.

2. The method of claim 1 further comprising sonicating solvent in step i to disperse the palladium nanoparticles and to reduce aggregation of the palladium nanoparticles.

3. The method of claim 1 wherein the solvent is selected from toluene, dimethylformamide, tetrahydrofuran, xylenes, and combinations thereof.

4. The method of claim 1 wherein the catalyst ink further comprises a binder selected from poly-vinyl alcohol and carboxy-methyl cellulose or combinations thereof.

5. The method of claim 1 wherein the palladium nanoparticles have an average particle size of from about 15 to about 400 nm.

6. The method of claim 1 wherein the palladium nanoparticles are present in the solution in an amount of from 0.1 to 2.2 wt. % based on total weight of the solution.

7. The method of claim 1 wherein the substrate is selected from glass, plastic, ceramic, or metal.

8. The method of claim 1 further comprising
v. applying a non-conductive layer prior to or after repeating steps ii and iii.

9. The method of claim 1 wherein the palladium nanoparticles have an average particle size of from about 15 to about 100 nm.

10. The method of claim 1 wherein the palladium nanoparticles have an average particle size of from about 200 to about 400 nm.

11. A method of forming a three-dimensional construct comprising
i. preparing a catalyst ink comprising a colloidal solution comprising palladium nanoparticles and a solvent selected from toluene, dimethylformamide, tetrahydrofuran, xylenes, and combinations thereof;
ii. sonicating the catalyst ink to disperse the palladium nanoparticles and to reduce aggregation of the palladium nanoparticles;
iii. depositing the catalyst ink from step (ii) onto a surface of a substrate using aerosol jet printing;
iv. subjecting the substrate to electro-less copper plating to plate the palladium nanoparticles with copper; and
v. repeating steps iii and iv until the three-dimensional construct is formed.

12. The method of claim 11 wherein the palladium nanoparticles have an average particle size of from about 15 to about 400 nm.

13. The method of claim 11 wherein the palladium nanoparticles are present in the solution in an amount of from 0.1 to 2.2 wt. % based on total weight of the solution.

14. The method of claim 11 wherein the catalyst ink further comprises a binder selected from poly-vinyl alcohol and carboxy-methyl cellulose or combinations thereof.

15. The method of claim 11 wherein the substrate is selected from glass, plastic, ceramic, or metal.

16. The method of claim 11 further comprising
vi. applying a non-conductive layer prior to or after repeating steps iii and iv.

17. The method of claim 11 wherein the palladium nanoparticles have an average particle size of from about 15 to about 100 nm.

18. The method of claim 11 wherein the palladium nanoparticles have an average particle size of from about 200 to about 400 nm.

Assignees

• Science Appl Int Corp

Inventors

• Morris David
• Timler John
• Schipp Jason

Classifications

• C23C18/38 Primary

  Coating with copper · CPC title

• C23C18/2053

  only one step pretreatment · CPC title

• C23C18/1879

  Use of metal, e.g. activation, sensitisation with noble metals · CPC title

• C23C18/1831

  Use of metal, e.g. activation, sensitisation with noble metals · CPC title

• C23C18/1608

  from pretreatment step, i.e. selective pre-treatment · CPC title