CONDUCTIVE INK COMPOSITIONS AND METHODS FOR PREPARATION OF STABILIZED METAL-CONTAINING NANOPARTICLES

• US 20140312284A1
• Filed: 04/19/2013
• Published: 10/23/2014
• Est. Priority Date: 04/19/2013
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Liu, Ping, Mokhtari, Mahya, Tahmoures-Zadeh, Tila, Gaynor, Roger, Wu, Yiliang, Hu, Nan-Xing
• Granted Patent: US 9,725,614 B2
• Time in Patent Office: Days
• US Class Current: 252/514
• CPC Class Codes: B22F 1/07 Metallic powder characterised by particles having a nanoscale microstructure nanosized particles B22F1/054
• CPC Class Codes: B22F 2009/245 Reduction reaction in an Ionic Liquid [IL]
• CPC Class Codes: B22F 2301/255 Silver or gold
• CPC Class Codes: B22F 2303/01 Main component
• CPC Class Codes: B22F 2304/05 Submicron size particles
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 9/24 starting from liquid metal compounds, e.g. solutions
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: H01B 1/02 mainly consisting of metals or alloys

Abstract

Processes for preparing stabilized metal-containing nanoparticles comprising silver and/or a silver alloy composite by reacting a silver compound with a reducing agent comprising a hydrazine compound at a temperature between about 20° C. and about 60° C. The reaction being carried out by incrementally adding the silver compound or a mixture of the silver compound and a stabilizer to a solution comprising the reducing agent, a stabilizer, and a solvent. Conductive ink compositions containing stabilized metal-containing nanoparticles prepared by such processes.

Claims

1. A conductive ink composition comprising:

a plurality of stabilized metal-containing nanoparticles comprising silver and/or a silver alloy composite, and

at least one ink vehicle,

wherein the plurality of stabilized metal-containing nanoparticles are dispersed in the ink vehicle, and

wherein the stabilized metal-containing nanoparticles are prepared by a first method comprising reacting a silver compound with a reducing agent comprising a hydrazine compound by incrementally adding the silver compound to a first mixture comprising the reducing agent, a stabilizer comprising an organoamine, and a solvent.

2. The conductive ink composition of claim 1, wherein the ink composition comprises greater than about 15 weight percent silver.

3. The conductive ink composition of claim 1, wherein the stabilized metal-containing nanoparticles have an increased dispersibility in the at least one ink vehicle as compared to stabilized metal-containing nanoparticles prepared by a second method comprising providing a second reaction mixture of the silver compound and the stabilizer, and adding the reducing agent to the second reaction mixture, and wherein the silver compound, the stabilizer and the reducing agent are the same in the first method and the second method.

4. The conductive ink composition of claim 1, wherein the silver compound is added to the first mixture as a dissolved component of a metal-containing solution or as a powder form.

5. The conductive ink composition of claim 1, wherein the stabilized metal-containing nanoparticle further comprises a metal selected from the group consisting of gold, platinum, palladium, copper, cobalt, chromium, nickel, and mixtures of two or more thereof.

6. The conductive ink composition of claim 1, wherein the stabilized metal-containing nanoparticle comprises a silver alloy composite selected from the group consisting of a silver-copper composite, a silver-gold-copper composite, silver-gold-palladium composite, and mixtures of two or more thereof.

7. The conductive ink composition of claim 1, wherein the silver compound comprises a silver salt selected the group consisting of silver acetate, silver trifluoroacetate, silver halide, silver sulfate, silver nitrate, silver hydrocarbylsulfonate, and a mixture of two or more thereof.

8. The conductive ink composition of claim 1, further comprising a resin.

9. The conductive ink composition of claim 1, wherein the hydrazine compound is selected from the group consisting of hydrazine or its corresponding salt, a hydrocarbylhydrazine, a hydrocarbylhydrazinium salt, a carbohydrazide, a semicarbazide, a sulfonohydrazide, and a mixture of two or more thereof.

10. The conductive ink composition of claim 1, wherein the organoamine comprises a hydrocarbylamine having at least 4 carbon atoms.

11. The conductive ink composition of claim 1, wherein the organoamine is selected from the group consisting of butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, hexadecylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, diaminopentane, diaminohexane, diaminoheptane, diaminooctane, diaminononane, diaminodecane, dipropylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, methylpropylamine, ethylpropylamine, propylbutylamine, ethylbutylamine, ethylpentylamine, propylpentylamine, butylpentylamine, tributylamine, trihexylamine and mixtures of two or more thereof.

12. The conductive ink composition of claim 1, wherein the mole ratio of the stabilizer to the silver compound is at least about 1:

1.

13. The conductive ink composition of claim 1, wherein the reaction of the silver compound with the reducing agent is carried out at a temperature between about 20°

C. and about 60°

C.

14. The conductive ink composition of claim 1, wherein the reducing agent is a phenylhydrazine and the stabilizer is dodecylamine.

15. The conductive ink composition of claim 1, wherein the stabilized metal-containing nanoparticles possess an annealing point of lower than about 125°

C., at which temperature the stabilized metal-containing nanoparticles form a metal framework with a conductivity of at least 3.0×

10⁴ S/cm.

16. A process for preparing stabilized metal-containing nanoparticles comprising silver and/or a silver alloy composite comprising:

reacting a silver compound and/or a silver complex with a reducing agent comprising a hydrazine compound at a temperature between about 20°

C. and about 60°

C.,

wherein the reaction is carried out by incrementally adding the silver compound and/or the silver complex to a mixture comprising the reducing agent, a stabilizer comprising an organoamine, and a solvent.

17. The process of claim 16, wherein the reaction mixture contains a substantially constant silver ion concentration during the period of incrementally adding the silver compound and/or silver complex.

18. The process of claim 16, wherein the stabilized metal-containing nanoparticles possess an annealing point of lower than about 125°

C., at which temperature the stabilized metal-containing nanoparticles form a metal framework with a conductivity of at least 3.0×

10⁴ S/cm.

19. A process for producing stabilized silver nanoparticles comprising:

(a) providing a mixture of a reducing agent, a stabilizer, and a solvent;

(b) (i) incrementally adding a silver compound to the mixture or (ii) incrementally adding a complex comprising a silver compound and an organoamine stabilizer to the mixture, wherein the temperature of the mixture is maintained below about 60°

C. as the mixture is reacted, and wherein a soluble silver ion concentration remains low in the mixture.

20. The process of claim 19, wherein the reaction is carried out at a temperature between about 30°

C. and about 50°

C.