Transparent conductors and methods for fabricating transparent conductors

• US 7,727,578 B2
• Filed: 12/27/2007
• Issued: 06/01/2010
• Est. Priority Date: 12/27/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Lem, Kwok-Wai, Yu, Lingtao, Guiheen, James V.
• Primary Examiner(s): Talbot; Brian K
• Application Number:
  US11/964,860
• Publication Number:
  US 20090166055A1
• Time in Patent Office: 887 Days
• Field of Search: 427/58, 427/98.4, 427/98.6, 427/99.2, 427/256, 427/377, 427/421.1, 427/428.01, 427/429, 427/430.1
• US Class Current: 427/58
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys

Abstract

Transparent conductors and methods for fabricating transparent conductors are provided. In one exemplary embodiment, a method for fabricating a transparent conductor comprises forming a dispersion comprising a plurality of conductive components and a solvent, applying the dispersion to a substrate in an environment having a predetermined atmospheric humidity that is based on a selected surface resistivity of the transparent conductor, and causing the solvent to at least partially evaporate such that the plurality of conductive components remains overlying the substrate.

Claims

1. A method for fabricating a transparent conductor having a predetermined first surface resistivity, the method comprising the steps of:

forming a dispersion comprising a first plurality of conductive components and a solvent;

determining a first atmospheric humidity in the range of about 50% to about 70%, the predetermined first surface resistivity based on the first atmospheric humidity;

applying the dispersion to a substrate in an environment having the first atmospheric humidity; and

causing the solvent to at least partially evaporate such that the first plurality of conductive components remains overlying the substrate.

2. The method of claim 1, further comprising the step of subjecting the substrate to a pretreatment before applying the dispersion to the substrate.

3. The method of claim 1, wherein the first atmospheric humidity is in the range of about 55% to about 60%.

4. The method of claim 1, wherein the first plurality of conductive components comprises a first plurality of silver nanowires, wherein the predetermined first surface resistivity is based on the first atmospheric humidity when the first plurality of silver nanowires comprises a first silver content, and wherein the first atmospheric humidity is higher than a second atmospheric humidity upon which is based a second surface resistivity equal to the predetermined first surface resistivity when a second plurality of nanowires has a second silver content that is greater than the first silver content.

5. The method of claim 1, wherein the step of applying the dispersion further comprises applying the dispersion by brushing, painting, screen printing, stamp rolling, rod or bar coating, inkjet printing, or spraying the dispersion onto the substrate, dip-coating the substrate into the dispersion, or rolling the dispersion onto the substrate.

6. The method of claim 1, wherein the dispersion comprises dispersants, surfactants, polymerization inhibitors, corrosion inhibitors, light stabilizers, wetting agents, adhesion promoters, binders, antifoaming agents, detergents, flame retardants, pigments, plasticizers, thickeners, viscosity modifiers, rheology modifiers, photosensitive materials, photoimageable materials, or mixtures thereof.

7. The method of claim 1, wherein the step of causing the solvent to at least partially evaporate results in the formation of a transparent conductive coating disposed on the substrate and wherein the method further comprises the step of subjecting the transparent conductive coating to a post-treatment after the step of causing the solvent to at least partially evaporate.

8. The method of claim 7, wherein the post-treatment step comprises subjecting the transparent conductive coating to an alkaline.

9. The method of claim 1, wherein the first plurality of conductive components comprises a plurality of metal nanowires.

10. The method of claim 1, wherein the first plurality of conductive components comprises a plurality of carbon nanotubes.

11. A method for fabricating a transparent conductor, the method comprising the steps of:

providing a substrate;

forming a dispersion comprising a first plurality of silver nanowires and a solvent;

applying the dispersion to the substrate in an environment having an atmospheric humidity within a range of about 50%to about 70%; and

at least partially evaporating the solvent such that the first plurality of silver nanowires remains overlying the substrate.

12. The method of claim 11, wherein the atmospheric humidity is within a range of about 55% to about 60%.

13. The method of claim 11, wherein the step of applying the dispersion to a substrate comprises the step of applying the dispersion to the substrate in the environment having a first atmospheric humidity, wherein a first resistivity of the transparent conductor is based on the first atmospheric humidity when the first plurality of silver nanowires comprises a first silver content, and wherein the first atmospheric humidity is higher than a second atmospheric humidity upon which is based a second resistivity equal to the first resistivity when a second plurality of nanowires has a second silver content that is greater than the first silver content.

14. The method of claim 11, wherein the step of applying the dispersion further comprises applying the dispersion by brushing, painting, screen printing, stamp rolling, rod or bar coating, inkjet printing, or spraying the dispersion onto the substrate, dip-coating the substrate into the dispersion, or rolling the dispersion onto the substrate.

15. The method of claim 11, wherein the dispersion comprises a dispersant, a surfactant, a polymerization inhibitor, a corrosion inhibitor, a light stabilizer, a wetting agent, an adhesion promoter, a binder, an antifoaming agent, a detergent, a flame retardant, a pigment, a plasticizer, a thickener, a viscosity modifier, a rheology modifier, a photosensitive material, a photoimageable material, or mixtures thereof.

16. The method of claim 11, wherein the step of causing the solvent to evaporate results in the formation of a transparent conductive coating disposed on the substrate and wherein the method further comprises the step of subjecting the transparent conductive coating to a post-treatment after the step of at least partially evaporating the solvent.