| 摘要 |
PROBLEM TO BE SOLVED: To easily improve the functionality of powder at a low cost by composing at least one layer of coating of a coating-coated powder having coating on the surface of fundamental particles of the one formed by reaction from metal salt in an aq. solvent under a specific pH condition. SOLUTION: By using an aq. solvent under a specific pH condition as a coating producing reactive solvent, solid phase coating can uniformly be formed on the surface of substrate particles while the flocculation of the particles are suppressed without precipitating only the solid phases into the liq. phases. In this case, at the time of using a buffer soln. as the solvent and precipitating them at a specific pH and at a suitable rate, the precipitation of the solid phases which are not formed into coating can be suppressed, and coating with a uniform thickness can be formed in a desired thickness. Moreover, by regulating the pH to specific one, the electric charges in the surface are simultaneously maintained to specific ones, so that the dispersed particles can be obtd. without flocculation in the coating-coated powder owing to the operation of electric double layers. Thus, the coating formation can satisfactorily be executed with water as the solvent without depending on an expensive alkoxide method. |
