Enhanced transparent conductive coatings and methods for making them
Transparent conductive coated devices (films, three dimensional objects and others) produced through coating with a nano metal containing emulsion which forms a conductive pattern with enhanced electrical, optical and other properties.
1. A method of forming a transparent conductive coating on a substrate comprising;
a. admixing metal nanopowder in a solvent with at least one ingredient of the group consisting of binder, surfactant, additive, polymer, buffer, dispersant and/or coupling agent to form an homogenized mixture;
b. admixing the homogenized mixture with water or a water miscible solvent or mixture of solvents to form an emulsion;
c. applying the emulsion on a surface of a substrate to be coated;
d. evaporating the solvent from the coated emulsion;
e. sintering the coated layer to form a conductive pattern comprising a network of thin, interconnected metal traces defining openings on the substrate; and
electroplating the conductive pattern with an electrolyte composition containing metal ions
wherein the following steps are added before the electroplating step:
(i) depositing a photoresist material on the transparent conductive coating, filling the openings in the pattern and covering the conductive pattern;
(ii) irradiating the photoresist material through the substrate in a manner that only the photoresist material in the openings of the pattern is exposed; and
(iii) washing away the unexposed photoresist material;
and wherein the remainder of the photoresist is removed from the coating after electroplating.
2. The method of claim 1 wherein the metal ions comprise copper ions.
3. The method of claim 1 wherein the metal ions comprise nickel ions.