Steel Sheet Having Coating Containing Self Healing Microcapsule Encapsulating Inorganic Compound and Coating Composition Comprising the Micro Capsule

摘要

A microcapsule is provided to ensure excellent self healing property and corrosion resistance by coating an inorganic salt compound at a metal part damaged by elution an encapsulated inorganic compound when applying external shock. A microcapsule(1) is included in a self-healing surface treatment composition for surface-treating a steel sheet(5) and comprises an inorganic compound inside a polymer shell as a core material. The inorganic compound is selected from the group consisting of cerium, magnesium, vanadium, zirconium, lanthanum, cobalt and their mixture. A method for manufacturing the microcapsule comprises the steps of: dispersing a core construction material of an inorganic compound in the form of small droplets stable to a medium solution by using a dispersion stabilizer having a micelle structure; injecting a liquid shell configuration material of low molecular weight in the media solution; and growing the shell configuration material of low molecular weight to form a microcapsule.