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D ETECTING the arrangement of intersecting stamp-pad ink and the toner of laser printing strokes is an excellent method of examining the documents originality. In this study, different six brands of stamp-pad inks, toner of five laser printers of various brands and models, three types of paper surfaces, two kinds of seal materials and three methods of seal manufactures were utilized to produce the samples of heterogeneous intersecting strokes. A combination of the microscopic method as a digital microscope and analytical instrumental technique as Raman spectroscopy were performed to determine the arrangement of intersecting strokes. The digital microscope succeeds in the detection of the arrangement of intersecting strokes of some stamp-pad inks and fails in detection the others depending on their brands and colors through notation four physical properties at intersection point the specular reflection, the ink and toner glosses, gaps and spreading. The Raman spectroscopy determined the ink or toner stamped or printed later by comparison the spectra of pure ink, toner, and their intersections and succeeds in detection all samples through the spectral data such as peak location and peak intensity. The combination of a digital microscope and Raman spectroscopy which applied successfully discriminates the arrangement of intersecting strokes of toner and all brands of stamp-pad inks regardless of their brands and color.

D ETERMINATION the sequence of intersecting strokes is great evidence in the field of the authentication of documents. Two types of the intersection utilized in preparing the samples of gel ink and toner. The effect of the brands and models of a laser printer, the brands, and colors of gel pen, the nature of the paper surface and the time gap were studied. The samples were examined by two nondestructive techniques., the digital microscope and Raman spectroscopy. The ink properties observed under the digital microscope succeed in determining the sequence of intersection except in case of some colors of some pen brands. Raman spectroscopy combines with a digital microscope to analyze the samples which indistinguishable by the digital microscope. The combination of a digital microscope and Raman spectroscopy is an excellent forensic base to full discrimination the sequence of intersecting strokes regardless of the brands or colors of gel ink.

I N THE forensic document examination, the decision of the historical order of intersection strokes between the toner and ballpoint inks is paramount a challenge issue. Two kinds of intersections are produced on three different kinds of papersheets. The digital microscope and Raman spectroscopy are two non-destroy techniques used to decide, these sequences via cross lines. Four physical properties obtained at the crossing point under the digital microscope were, specular reflection, ink gloss, ink spreading and gap. The results of the digital microscope detect that the two kinds of crossing strokes except the red color of ink crossed over the toner. The results of Raman spectroscopy manifested that the crossing point similar to the pure ink executed later. The complementary techniques of Raman spectroscopy and the digital microscope were necessary to achieve a complete determination of the stroke's intersection sequences of the toner and ballpoint ink.