Abstract: A heuristic process for color formula calculation of pigmented shades matched to a target shade, comprising the steps of i) using suitable calibration scales to compile an effect matrix for each of the ingredients included in a coloring system, ii) determining the optical materials parameters of the target shade, iii) selecting a suitable starting formula, iv) determining the color difference between the starting formula and the target shade, v) calculating a first matched color formula while taking account of the effect matrices, vi) repeating steps iv) and v) until an acceptable remaining color difference is reached, wherein the effect matrices are continually updated with shade-relevant information during ongoing operation, achieves an improvement on the existing processes for shade formula calculation, not only in terms of reducing the number of tinting steps needed but also in terms of minimizing the remaining color difference.

Abstract: A heuristic process for color formula calculation of pigmented shades matched to a target shade, comprising the steps of i) using suitable calibration scales to compile an effect matrix for each of the ingredients included in a coloring system, determining the optical materials parameters of the target shade, iii) selecting a suitable starting formula, iv) determining the color difference between the starting formula and the target shade, v) calculating a first matched color formula while taking account of the effect matrices, vi) repeating steps iv) and v) until an acceptable remaining color difference is reached, wherein the effect matrices are continually updated with shade-relevant information during ongoing operation, achieves an improvement on the existing processes for shade formula calculation, not only in terms of reducing the number of tinting steps needed but also in terms of minimizing the remaining color difference.

Abstract: A method of preparing effect pigment color formulas matched to a color original, comprising the steps of (a) producing a calibration series for each pigment included in the coloring system of an effect pigment color original, (b) experimentally determining the reflectances R? of the color original and of the calibration series, (c) calculating the optical parameters of the color original and of the constituents of the coloring system, (d) selecting a suitable starting formula, (e) determining the residual color difference between the starting formula and the color original, (f) producing a first matched color formula, (g) and repeating steps (e) and (f) until the residual color difference between the matched color formula and the color original is acceptable, which involves (i) transforming the reflectances R? of the color original and of the calibration series by means of a suitable mathematical function such that all of the transformed reflectances R?? lie between 0 and 1, and (ii) calculating the optical