Dermatological topical agent composition containing useful component-including taurine crystals

A method for producing a fine needlelike taurine crystal including a useful component in the crystal, the method comprising a step of growing a crystal in an environment in which an aqueous solution (A) containing taurine dissolved is mixed with or held in contact with a liquid substance (B) having low solubility of taurine, wherein the useful component is dissolved or dispersed in the aqueous solution (A) or the liquid substance (B), whereby the useful component is included in the crystal along with the growth of the crystal.

A method for producing an external-use skin preparation composition comprising a fine needlelike taurine crystal including a useful component in the crystal, the method comprising the following steps:

• a step of growing a crystal in an environment in which an aqueous solution (A) containing taurine dissolved is mixed with or held into contact with a liquid substance (B) having low solubility of taurine, wherein a useful component is dissolved or dispersed in the aqueous solution (A) or the liquid substance (B), whereby the useful component is included in the crystal along with the growth of the crystal;
• and
• blending the fine needlelike taurine crystal including the useful component in the crystal, which is obtained in the step of growing a crystal, into an external-use skin preparation composition.