▎ 摘　　要

NOVELTY - Preparing a carbon electrode, involves adding and dissolving Polyvinyl butyral (PVB) and anhydride in a solvent, introducing the anhydride-derived acid into the PVB contained in the precursor solution, and washing and drying the modified polyvinyl butyral. USE - The method for preparing a carbon electrode for use in sensor such as air filter among a mask, an air purifier, and a heat exchanger (all claimed). ADVANTAGE - The method provides real-time monitoring of the fine dust content is possible through a change in resistance according to the fine dust content adsorbed to the carbon electrode, and also has a replacement time confirmation function. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a carbon dispersion, which comprises modified polyvinyl butyral, carbon and a solvent; (2) a carbon electrode, which comprises a carbon coating layer formed by coating the carbon dispersion; (3) an energy storage device, and sensor, which comprises the carbon electrode; (4) an application product having a replacement time confirmation function, which comprisesthe sensor; and (5) a fine dust adsorbent, which comprises a carbon coating layer formed by coating the carbon dispersion.