FIELD: measuring equipment.
SUBSTANCE: method for determining the age of printed texts of paper-based documents using Raman spectroscopy. When implementing the method on a sheet of paper with the text under study, toner is removed from the elements of the printed text on at least three points. The radiation is focused on the points from which the toner has been removed and on at least three points on the paper free of toner, and the Raman spectra are measured. Based on the ratios of the characteristic peaks of toner-free paper, the conventional production date of toner-free paper is determined. Then, based on the ratios of the characteristic peaks of the paper that was under the toner, the conventional manufacturing date of the paper that was under the toner from which the toner was removed is determined. Based on the average statistical values of the intensity ratio of the 280 cm-1 peak in the spectra of the paper that was under the toner, to a similar peak in the spectra of the paper free of toner, the date range for applying the printed text is determined.
EFFECT: extending the deadline for determining how long ago a document was created, as well as reducing the likelihood of an expert error.
1 cl, 11 dwg, 1 tbl, 1 ex
