METHOD FOR DESIGNING PEARL PIGMENT AND MAKEUP COSMETIC

PROBLEM TO BE SOLVED: To determine constitution and a film thickness when a pearl pigment of a desired color is designed without depending on trial and error or experiences of a craftsman. SOLUTION: The pearl pigment is designed by selecting a composite refractive index, a thickness and a desired reflected light wavelength of flaky powder, applying the selected items, determining a multi-layered film reflectance R of the pearl pigment and determining the film thickness of each coating layer so that the multi-layered film reflectance R is the maximum or minimum at a desired wavelength. Thereby, the pearl pigment is designed so that the value of the determined film thickness is obtained. Furthermore, the average reflectance F in consideration of the thickness distribution of the flaky powder is determined and utilized in place of the multi-layered film reflectance R. Otherwise, the Torrance-Sparrow model is applied to determine coated surface reflectance RC in consideration of the tilt of the pearl pigment for the coated surface when coating a rough surface with the pearl pigment. The resultant coated surface reflectance RC is utilized in place of the multi-layered film reflectance R or the average reflectance F. Thereby, simulation in consideration of the thickness distribution of the flaky powder and coating roughness for the rough surface can be carried out. COPYRIGHT: (C)2008,JPO&INPIT