Silver-organo-complex ink with high conductivity and inkjet stability

Patent metadata

Field	Value
Publication number	US-10597547-B2
Application number	US-201615779363-A
Country	US
Kind code	B2
Filing date	Dec 13, 2016
Priority date	Dec 14, 2015
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

A robust formulation of silver-organo-complex (SOC) ink and method of making same are provided. In an aspect, the complexing molecules act as reducing agents. The silver loaded ink can be printed and sintered on a wide range of substrates with uniform surface morphology and excellent adhesion.

First claim

Therefore, the following is claimed:

1. An ink composition for making a silver structure, the ink composition comprising a silver-organo-complex, a solvent, an anion of acetic acid and an anion of formic acid;
wherein the silver-organo-complex comprises a silver cation complexed with a first complexing agent and a second complexing agent;
wherein the first complexing agent is an alkyl amine and the second complexing agent is an alkanolamine.

2. The ink composition of claim 1 , wherein the alkyl amine is selected from the group consisting of methylamine, ethylamine, propylamine, butylamine, and amylamine.

3. The ink composition of claim 1 , wherein the alkanolamine is selected from the group consisting of methanolamine, ethanolamine, propanolamine, and butanolamine.

4. The ink composition of claim 1 , wherein the ink composition has a pH of 9-14.

5. The ink composition of claim 1 , wherein said ink composition further comprises an additive selected from the group consisting of 2-hydroxyethylcellulose (2-HEC), 2,3-butanediol, glycerol, ethylene glycol, and combinations thereof.

6. The ink composition of claim 5 , wherein the ink composition comprises 2-HEC having a molecular weight of 90,000.

7. The ink composition of claim 1 , wherein said solvent is selected from the group consisting of water, short chain alcohols having an alkyl chain of 1-3 carbon atoms, and a combination thereof.

8. The ink composition of claim 1 , wherein the ink composition has a viscosity of about 4.95 mPa·s to about 5.97 mPa·s.

9. The ink composition of claim 1 , wherein the ink composition has a surface tension of about 30.7 mN/m to about 33.08 mN/m.

10. The ink composition of claim 1 , wherein the ink composition has a sintering temperature of about 80° C. to about 150° C.

11. The ink composition of claim 1 , wherein the alkyl amine is ethylamine and the alkanolamine is ethanolamine.

12. A method of forming a conductive silver structure, comprising:
depositing an ink composition according to claim 1 onto a surface using a nozzle of an inkjet printing head; and
reducing said ink composition deposited on said surface.

13. The method of claim 12 , wherein the conductive silver structure is a Radio-Frequency (RF) electronic device.

14. The method of claim 13 , wherein said nozzle is a 1 pL to a 10 pL piezoelectric nozzle.

15. The method of claim 14 , wherein said surface is selected from the group consisting of polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), glass, and 3D printed substrates.

16. The method of claim 15 , wherein said reducing is sintering at a temperature of about 80° C. to about 150° C.

17. The method of claim 16 , further comprising:
depositing a second layer of the ink composition on the sintered ink composition;
and sintering the second layer of the deposited ink composition.

18. The method of claim 16 , wherein ink composition further comprises an additive selected from the group consisting of 2-HEC having a molecular weight of 90,000 and 2,3-butanediol.

19. A method of making an ink composition, comprising:
combining a first complexing solution, a second complexing solution, and a silver salt to form a silver-organo-complex, wherein the first complexing solution comprises an alkyl amine, and the second complexing solution comprises an alkanolamine and a carboxylic acid, and the silver-organo-complex comprises a silver cation complexed with the alkyl amine and the alkanolamine; and
filtering the ink composition to produce a clear and transparent solution.

20. The method of claim 19 , further comprising preparing the second complexing solution by adding the carboxylic acid to the alkanolamine to adjust the pH to 9-10.5.

Assignees

• Univ King Abdullah Sci & Tech

Inventors

• Vaseem Mohammad
• Mckerricher Garret
• Shamim Atif

Classifications

• C09D11/52 Primary

  Electrically conductive inks · CPC title

• H05K2203/121

  Metallo-organic compounds · CPC title

• H05K2203/125

  Inorganic compounds, e.g. silver salt · CPC title

• H05K1/095

  for polymer thick films, i.e. having a permanent organic polymeric binder · CPC title

• C09D11/38

  characterised by non-macromolecular additives other than solvents, pigments or dyes · CPC title