The present invention provides a tyrosine derivative and a solid particulate material (and optionally melanin), and an effective time for impregnating at least one of the tyrosine derivative and the solid particulate material with the other of the tyrosine derivative and the solid particulate material. And applying a force to the tyrosine derivative and the solid particulate material under conditions. The present invention also provides a composition comprising at least one of a tyrosine derivative impregnated with a solid particulate material and a solid particulate material impregnated with a tyrosine derivative.本発明は、チロシン誘導体と固体粒状物質（及び任意にメラニン）を準備し、前記チロシン誘導体及び前記固体粒状物質の少なくとも一方に前記チロシン誘導体及び前記固体粒状物質の他方を含浸させるのに有効な時間及び条件下で、前記チロシン誘導体及び前記固体粒状物質に力を適用することを含む方法を提供する。本発明はまた、固体粒状物質を含浸させたチロシン誘導体及びチロシン誘導体を含浸させた固体粒状物質の少なくとも一つを含む組成物も提供する。
