Metal nanowire ink for the formation of transparent conductive films with fused networks
Fusing nanowire inks are described that can also comprise a hydrophilic polymer binder, such as a cellulose based binder. The fusing nanowire inks can be deposited onto a substrate surface and dried to drive the fusing process. Transparent conductive films can be formed with desirable properties.
1. A metal nanowire ink comprising an aqueous solvent, from about 0.001 wt % to about 4 wt % metal nanowires, from about 0.00025 to about 0.5 wt % metal ions, and fluoride anions.
2. The metal nanowire ink of claim 1 wherein the aqueous solvent comprises from about 5 wt % to about 60 wt % liquid alcohol.
3. The metal nanowire ink of claim 2 wherein the liquid alcohol is ethanol.
4. The metal nanowire ink of claim 1 wherein a pH of the ink is at least about 3 pH units.
5. The metal nanowire ink of claim 1 wherein a pH of the ink is from about 5.5 to about 7.5 pH units.
6. The metal nanowire ink of claim 1 further comprising from about 0.05 wt % to about 5 wt % solid hydrophilic polymer binder soluble in the aqueous solvent.
7. The metal nanowire ink of claim 1 wherein the hydrophilic polymer binder comprises a polymeric polyol.
8. The metal nanowire ink of claim 1 wherein the hydrophilic polymer binder comprises a polysaccharide.
9. The metal nanowire ink of claim 1 wherein the hydrophilic polymer binder comprises a cellulose based polymer or chitosan based polymer.
10. The metal nanowire ink of claim 1 wherein the metal nanowires comprise silver nanowires and the metal ions comprise silver ions.
11. The metal nanowire ink of claim 10 comprising from about 0.01 wt % to about 2 wt % of the silver nanowires, and from about 0.001 to about 0.2 wt % of the silver ions, and the metal nanowire ink further comprising from about 0.1 wt % to about 2 wt % of a polysaccharide polymer binder.
12. The metal nanowire ink of claim 1 wherein the metal ions and the fluoride anions are provided as silver fluoride.
13. The metal nanowire ink of claim 1 comprising about 0.0001 to about 0.1 wt % fluoride ions.
14. The metal nanowire ink of claim 1 wherein no visible settling can be observed after one hour of sitting without stirring.
15. The metal nanowire ink of claim 1 further comprising from about 0.01 wt % to about 2.5 wt % curable binder.