METHOD FOR DETERMINING REMOTENESS OF WRITING OF WRITTEN TEXTS AND OTHER WRITING MATERIALS Russian patent published in 2007 - IPC G01N21/31 

FIELD: expertise of documents, possible use in investigation, forensics, criminalistics and court practice, and also during technical expertise when determining authenticity and age of various sorts of accounting, banking, legal, historical and other written texts and documents, made by inks of ball-pens, capillary, gel pens, imprints, and other writing materials.

SUBSTANCE: method includes producing two samples of researched writing material, one of which is extracted by solvent, another one is first subjected to heating, and then extracted under same conditions. Both samples are subjected to spectrum-photometry and ratio of optical densities of solutions are produced in area of their maximum for unit of stroke length in area ranging from 400 to 1100 nanometers. Determining of remoteness of researched document is performed by comparing these values to analogical parameters of documents with manufacture data known in advance, represented in graphical or table form.

EFFECT: increased detection precision.

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