A solid cosmetic soap is prepared by disposing a microcapsule in a material for alkaline solid makeup soap containing sodium bicarbonate, wherein an organic acid such as citric acid is pressed into the porous silica and the porous silica contains citric acid or the like Of organic acids to form microcapsules that produce carbon dioxide when using the solid makeup soap. In a material for solid makeup soap having a weight percentage of 88.0% to 98.0%, a mixed amount of 1.0% to 7.0% by weight of sodium bicarbonate A composition for use in an alkaline solid make-up soap, and in which a microcapsule having a weight percentage of 1.0% to 5.0% is prepared to produce a solid make-up soap in which the organic acid is pressed into the porous silica and So that the porous silica contains an organic acid to form a microcapsule, and carbon dioxide is produced when the solid makeup soap is used.
