▎ 摘　　要

NOVELTY - Solution comprises reduced graphene oxide powder and a reducing agent at a mixed ratio of (2:3)-(4:3). The solution has a concentration of 0.01-0.1 wt.%. USE - The solution is useful for a coating ink, which is useful in oxygen and moisture permeation prevention materials, antistatic materials, electromagnetic shielding materials, display devices (comprising light emitting device and organic LED), solar cells, thin film speakers, transistors (i.e. thin film transistors) and chemical sensors (all claimed). ADVANTAGE - The solution has high dispersion stability and electrical characteristics. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a coating ink prepared by mixing the solution and a secondary coating solution.