红外辐射法与茚二酮法显现纸张表面汗潜手印的比较研究

Comparison of infrared radiation method and 1,2-indanedione method for the development of fingerprints on paper

本研究分别使用红外辐射法和茚二酮法对报纸、打印纸、牛皮纸、热敏纸、卫生纸等常见纸张表面的汗潜手印进行显现,并从手印与客体之间的反差以及手印的清晰连贯程度两个角度对手印显现效果进行评价,最终得到不同纸张表面手印显现的最佳方法。实验结果表明,对于牛皮纸、卫生纸、打印纸、热敏纸表面的新鲜汗潜手印,使用两种方法显现手印的效果均较为理想,但对于遗留时间较长的汗潜手印,茚二酮法和红外辐射致碳化阶段显现要优于红外辐射致荧光阶段显现;对于报纸表面的汗潜手印,红外辐射致碳化阶段显现的效果最佳。本研究提出的两种方法可以有效显现常见纸类客体表面的汗潜手印,为纸张类客体表面潜在手印的高质量显现提供有益的参考。

In this study,infrared radiation method and 1,2-indanedione method were used to develop latent fingerprints on surface of common paper(i.e.newspaper,printing paper,kraft paper,thermo-sensitive paper and toilet paper).The developing results using above two methods were then evaluated in two aspects including the contrast between the fingerprint and the substrate,as well as the clearness and the coherence of the friction ridges.Finally,the appropriate methods for fingerprint development on common paper were obtained.The experimental results showed that,in the case of kraft paper,toilet paper,printing paper and thermo-sensitive paper,both 1,2-indandione and infrared radiation method could achieve satisfactory results for fresh fingerprint development,while 1,2-indanedione and infrared radiation carbonization method showed better results than infrared radiation fluorescence method for old fingerprint development;in the case of newspaper,infrared radiation carbonization method could exhibit better results than others for both fresh and old fingerprint development.Our proposed two methods can be used as an effective way to develop the latent fingerprints on common paper with high quality,which will provide benefit references for latent fingerprint development on common paper.