Transparent films with control of light hue using nanoscale colorants
Nanoscale colorants are introduced to adjust the hue of transparent conductive films, such as to provide a whiter film. The transparent conductive films can have sparse metal conductive layers, which can be formed using silver nanowires. Color of the film can be evaluated using standard color parameters. In particular, values of color parameter b* can be reduced with the nanoscale colorants without unacceptably changing other parameters, such as haze, a* and transparency.
1. A transparent conductive film comprising a substrate, a transparent conductive layer supported by the substrate, a coating and one or more nanoscale colorants, wherein a value of b* for the film is reduced at least about 0.1 units and total transmittance of visible light in percent is not decreased by more than about 2 relative to the corresponding film without the nanoscale colorants, wherein the nanoscale colorants comprise a metal nanoplate having an average thickness of no more than about 100 nanometers (nm) wherein the nanoscale colorants in a dilute dispersion have a peak absorption between 525 nm and 675 nm.
2. The transparent conductive film of claim 1 wherein the transparent conductive layer comprises a sparse metal conductive layer.
3. The transparent conductive film of claim 1 wherein the transparent conductive layer comprises a fused metal nanostructured network.
4. The transparent conductive film of claim 1 wherein the haze in percent units does not increase by more than 0.5 relative to the corresponding film without the nanoscale colorant.
5. The transparent conductive film of claim 1 having a total transmittance of visible light of at least about 85% and a haze of no more than about 1.2%, wherein the transparent conductive layer has a sheet resistance of no more than about 100 ohms/sq.
6. The transparent conductive film of claim 5 wherein the absolute value of b* and a* in the color scale are each no more than about 1.
7. The transparent conductive film of claim 1 wherein the nanoscale colorants are in the coating at a concentration from about 0.001 wt % to about 10 wt %.
8. The transparent conductive film of claim 1 wherein transparent conductive film comprises a sparse metal conductive layer and wherein the nanoscale colorants and a polymer binder are in the sparse metal conductive layer and the nanoscale colorants are at a concentration in the layer from about 0.1 wt % to about 50 wt %.
9. The transparent conductive film of claim 1 wherein the coating has from about 0.1 wt % to about 5 wt % nanoscale colorants.
10. The transparent conductive film of claim 1 wherein the coating comprises polysiloxanes, polysilsesquioxanes, polyurethanes, acrylic resins, acrylic copolymers, cellulose ethers and esters, nitrocellulose, other water insoluble structural polysaccharides, polyethers, polyesters, polystyrene, polyimide, fluoropolymer, styrene-acrylate copolymers, styrene-butadiene copolymers, acrylonitrile butadiene styrene copolymers, polysulfides, epoxy containing polymers, copolymers thereof, and mixtures thereof.
11. The transparent conductive film of claim 1 wherein the film is hue adjusted as expressed as an absolute value of the color scale a* being adjusted by at least about 0.1 relative to the equivalent film without the nanoscale colorants.
12. The transparent conductive film of claim 1 having a total transmittance of visible light of at least about 85% and a haze of no more than about 1.2%.
13. The transparent conductive film of claim 1 having a thickness from about 5 microns to about 1 mm.
14. A transparent conductive film comprising a substrate and a transparent conductive layer comprising a sparse metal conductive element and a polymer binder, wherein the transparent conductive layer comprises metal nanostructures having an absorption at 580 nm at least about 2 times the absorption at 475 nm, wherein the transparent conductive film has a value of b* lowered by at least about 0.1 and a value of % TT lowered by no more than about 2 relative to an equivalent transparent conductive layer without the metal nanostructures.
15. The transparent conductive film of claim 14 wherein the sparse metal conductive element comprises a fused metal nanostructured network and wherein the metal nanostructures may or may not be fused into the fused metal nanostructured network.
16. The transparent conductive film of claim 14 wherein the metal nanostructures comprise metal nanoplates, metal nanoshells or combinations thereof, which may be fused into the fused metal nanostructured network.
17. The transparent conductive film of claim 14 having a total transmittance of visible light of at least about 85% and absolute value of b* of no more than about 1.2 and a haze of no more than about 1.2%, and wherein the sparse metal conductive layer has a sheet resistance of no more than about 100 ohms/sq.
18. A coating solution comprising from about 0.02 wt % to about 80 wt % non-volatile polymer binder precursor compounds, from about 0.0001 wt % to about 2.5 wt % metal nanostructures, from about 0.01 wt % to about 1 wt % metal nanowires and solvent wherein the metal nanostructures have an absorption at 580 nm at least about 2 times the absorption at 475 nm.
19. The coating solution of claim 18 wherein the metal nanostructures comprise metal nanoplates, metal nanoshells, or metal nanoribbons or combinations thereof and wherein metal nanostructures in a dilute dispersion in water have a peak absorption between 525 nm and 675 nm.
20. The coating solution of claim 18 wherein the polymer comprises polysiloxanes, polysilsesquioxanes, polyurethanes, acrylic resins, acrylic copolymers, cellulose ethers and esters, nitrocellulose, other water insoluble structural polysaccharides, polyethers, polyesters, polystyrene, polyimide, fluoropolymer, styrene-acrylate copolymers, styrene-butadiene copolymers, acrylonitrile butadiene styrene copolymers, polysulfides, epoxy containing polymers, copolymers thereof, and mixtures thereof.
21. The coating solution of claim 18 wherein the solution can be coated to dry into a film with a thickness of no more than about 1 mm while having a total transmittance of visible light of at least 85% while adjusting the hue of the dried film as expressed as an absolute value of the color scale b*, a* or both being adjusted by at least about 0.1 relative to the equivalent film without the metal nanostructures.
22. A transparent conductive film comprising a substrate, a transparent conductive layer supported by the substrate, a coating and one or more nanoscale colorants, wherein a value of b* for the film is reduced at least about 0.1 units and total transmittance of visible light in percent is not decreased by more than about 2 relative to the corresponding film without the nanoscale colorants, wherein the transparent conductive layer comprises a fused metal nanostructured network.
23. The transparent conductive film of claim 22 wherein the nanoscale colorants comprise a metal nanoshell with a ceramic core having an average diameter of the primary particles of no more than about 100 nm.
24. The transparent conductive film of claim 22 wherein the haze in percent units does not increase by more than 0.5 relative to the corresponding film without the nanoscale colorant.
25. The transparent conductive film of claim 22 having a total transmittance of visible light of at least about 85% and a haze of no more than about 1.2%, wherein the transparent conductive layer has a sheet resistance of no more than about 100 ohms/sq.
26. The transparent conductive film of claim 25 wherein the absolute value of b* and a* in the color scale are each no more than about 1.
27. The transparent conductive film of claim 22 wherein the nanoscale colorants are in the coating at a concentration from about 0.001 wt % to about 10 wt %.
28. The transparent conductive film of claim 22 wherein the nanoscale colorants comprise metal nanoribbons.
29. The transparent conductive film of claim 22 wherein the coating has from about 0.1 wt % to about 5 wt % nanoscale colorants.
30. The transparent conductive film of claim 22 wherein the coating comprises polysiloxanes, polysilsesquioxanes, polyurethanes, acrylic resins, acrylic copolymers, cellulose ethers and esters, nitrocellulose, other water insoluble structural polysaccharides, polyethers, polyesters, polystyrene, polyimide, fluoropolymer, styrene-acrylate copolymers, styrene-butadiene copolymers, acrylonitrile butadiene styrene copolymers, polysulfides, epoxy containing polymers, copolymers thereof, and mixtures thereof.
31. The transparent conductive film of claim 22 wherein the film is hue adjusted as expressed as an absolute value of the color scale a* being adjusted by at least about 0.1 relative to the equivalent film without the nanoscale colorants.