Jornal de pesquisa forense

Non-Destructive Chemical Method and Simple Methods for Determining the Sequence of Intersecting Color Ballpoint Pen Stroke and Color Laser Printed Marking

Abstract

EL-Sabbah MMB, Gomaa AZ, El-Hefny DE, Ahmed S4

Non-destructive chemical method and simple methods for determining the sequence of intersecting color ballpoint pen stroke and color laser printed marking has been done. Different chemicals compounds such as pyridine, ethyl acetate, 2-phenoxyethanol, methanol, and ethyl alcohol are used to treatment glossy paper for lifting technique. These chemicals enhance the lifting technique in comparison with using glossy paper only especially with ethyl alcohol. Simple techniques such as side lighting technique depending on embossing phenomena, microscopically with both transmitted and external 45° light and absorbance/reflectance techniques are used. According to the results of the study and blind test, it is recommended that using the previous techniques should be done in the following order: lifting technique using ethyl alcohol treatment, lifting technique without treatment, side lighting (in case of presence embossing), and microscopically. Absorbance/reflectance techniques were excluded because the results obtained are misleading. All used techniques are simple, non-destructive and can be photographically demonstrated.