▎ 摘　　要

NOVELTY - Aqueous ink comprises 15-40 pts. wt. deionized water, 15-35 pts. wt. graphene slurry, 0.5-1.5 pts. wt. Carbon black, 5-15 pts. wt. positive temperature coefficient (PTC) functional materials, 2-6 pts. wt. organic additives and 30-65 pts. wt. emulsion. USE - Aqueous ink used in heating film (claimed). ADVANTAGE - The ink uses modified graphene to increase its stability in solvents and emulsions, and forms a stable conductive path with carbon black, so that insulating substrate polyethylene terephthalate film has excellent adhesion, and addition of PTC functional materials makes electrothermal film having excellent self-limiting temperature resistance, which effectively improves the safety of electrothermal film. The preparation is simple and highly efficient. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of aqueous ink, which involves adding emulsion and deionized water to reaction kettle and mixing for 20 minutes, adding graphene and carbon black and stirring for 30 minutes, adding PTC functional materials, 10-25 %mass dispersant, 15-20 %mass leveling agent, 15-25 %mass wetting agent and 20-25 %mass defoaming agent to reaction kettle and stirring for 30 minutes, grinding in sand mill to particle size of less than 25 mu m, and adding 20-25 %mass thickener and stirring evenly; and (2) use of aqueous ink in heating film.