Method for determining parameters specific to the custom-made coloring of the hairs of a given individual

A method for determining at least one characteristic non-colorimetric parameter of hairs of a given individual, the method for determining the at least one characteristic non-colorimetric parameter comprising the steps of:

• receiving a colorimetric deviation parameter specific to the given individual, and,
• determining at least one characteristic non-colorimetric parameter of the hairs of the given individual from the colorimetric deviation parameter received;
• the colorimetric deviation parameter being able to be obtained by a method for determining at least one parameter specific to the custom-made coloring of hairs of the given individual, according to a colorimetric rendering model, the method for determining the at least one parameter specific to the custom-made coloring of hairs comprising an initialization phase corresponding to a first coloring of the hairs of the individual, the initialization phase comprising the steps of:
• receiving at least one magnitude representative of a first target color in a colorimetric space,
• receiving at least one magnitude representative of a first initial color in the colorimetric space, the first color being the color of the hairs to be colored of the individual,
• determining a cosmetic product composition according to the magnitudes representative of the first initial color and of the first target color and of the colorimetric rendering model,
• applying a cosmetic product having the determined composition on the hairs to be colored of the individual in order to obtain colored hairs,
• evaluating the color of the colored hairs in order to obtain at least one magnitude representative of a first final color in the colorimetric space, and
• determining at least one colorimetric deviation parameter specific to the individual according to the magnitudes representative of the first final color and of the first target color;
• wherein the determining of the at least one characteristic non-colorimetric parameter of the hairs is carried out to adapt the care provided to the hairs in order to color the hairs of the individual or the type of cosmetic products to be applied on the hairs in order to color the hairs;
• and the method for determining the at least one characteristic non-colorimetric parameter of hairs is implemented by a device;
• wherein the receiving of the at least one magnitudes representative of the first target color and of the first initial color are implemented via a man-machine interface;
• wherein the determining of the cosmetic product composition is implemented by a controller in interaction with a computer program product;
• wherein the evaluating of the color of colored hairs is implemented by a colorimetric measuring unit;
• and
• wherein the determining of the at least one colorimetric deviation parameter is implemented by the controller in interaction with the computer program product.