Method for determining the migration potential of an at least partially cured energy curing ink and/or varnish printed on a substrate, and especially of a printed food packing

The present invention relates to a method for determining the migration potential of an at least partially cured energy curing ink and/or varnish printed on a substrate comprising: -providing a substrate, which is printed with the ink and/or varnish, which comprises at least one extractable compound, which absorbs or emits radiation at at least one wavelength between 190 and 3,000 nm, -cutting at least one sample from the printed substrate, placing and incubating the sample in a solvent, in which the extractable compound is soluble, and removing the sample from the solvent to obtain a solvent extract, -quantitatively measuring a spectroscopic characteristic of the solvent extract at at least one wavelength between 190 and 3,000 nm, at which the extractable compound absorbs or emits radiation, so as to obtain a measured numeric value of the spectroscopic characteristic, and -comparing the measured numeric value of the spectroscopic characteristic with a calibration curve.