Transparent conductive coating with filler material
An article is disclosed comprising a network-like pattern of conductive traces formed of at least partially-joined nanoparticles that define randomly-shaped cells that are generally transparent to light and contain a transparent filler material. In a preferred embodiment, the filler material is conductive such as a metal oxide or a conductive polymer. In another preferred embodiment, the filler material is an adhesive that is can be used to transfer the network from one substrate to another. A preferred method of forming the article is also disclosed wherein an emulsion containing the nanoparticles in the solvent phase and the filler material in the water phase is coated onto a substrate. The emulsion is dried and the nanoparticles self-assemble to form the traces and the filler material is deposited in the cells. An electroluminescent device is also disclosed wherein the article of the invention forms a transparent electrode in the device.
1. A process of forming an article comprising:
a. applying a liquid emulsion to the surface of a first substrate, wherein the liquid emulsion comprises (i) a discontinuous liquid phase and (ii) a continuous liquid phase that includes conductive nanoparticles and that evaporates more quickly than the discontinuous liquid phase;
b. drying the emulsion and subsequently forming a transparent conductive coating comprising a network of traces formed of at least partially-joined nanoparticles defining randomly-shaped cells transparent to light; and
c. applying a transparent filler material to at least partially fill at least some of the cells of the coating.
2. The process of claim 1 wherein the filler material is an adhesive.
3. The process of claim 2 further comprising the step of adhering a second substrate to the side of the article opposite the first substrate in contact with the adhesive.
4. The process of claim 3 further comprising the step of removing the first substrate from the article.
5. The process of claim 1 wherein the transparent filler material is an adhesive, the process comprising:
i. providing a second substrate having a surface coated with the adhesive;
ii. contacting the adhesive-coated surface of the second substrate with the transparent conductive coating to form a laminate; and
iii. removing the first substrate to at least partially fill at least some of the cells of the transparent coating with the adhesive.
6. The process of claim 1 wherein the filler material is conductive.
7. The process of claim 1 wherein the filler material is abrasion-resistant, scratch-resistant, moisture-resistant, or any combination thereof.