▎ 摘 要
NOVELTY - Aqueous based PTC conductive coating comprises PTC functional slurry and conductive slurry in mass ratio of (30-50): (50-70). The PTC functional slurry comprises 20-35 wt.% PTC functional components and 65-80 wt.% water. The PTC functional components includes 15-30 wt.% paraffin wax, 45-65 wt.% stearic acid, 10-25 wt.% emulsifier and 0.1-1 wt.% first defoamer. The conductive paste includes 30-40 wt.% adhesive, 0.3-1 wt.% second defoamer, 1-10 wt.% wetting and dispersing agent, 5-20 wt.% conductive carbon material and 40-60 wt.% water. USE - The aqueous based PTC conductive coating is useful in planar electric heating device (claimed). ADVANTAGE - The aqueous based PTC conductive coating has excellent self-limiting temperature performance; and is safe and environmentally friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing aqueous based PTC conductive coating comprising (a) mixing the components in PTC functional components to melt the paraffin and stearic acid under heating conditions to obtain a mixed liquid, mixing and emulsifying with water to obtain PTC functional slurry material, (b) mixing and grinding adhesive, second defoamer, wetting and dispersing agent and the conductive carbon material with water to obtain the conductive slurry and (c) mixing PTC functional paste with the conductive paste.