显微红外光谱分析热敏可擦签字笔字迹

Micro-infrared Spectroscopy Analyzing Writings about Their Componential Identity from Thermosensitive Erasable Signing Pens

目的探索显微傅里叶变换衰减全反射红外光谱(ATR-FTIR)技术鉴别热敏可擦签字笔书写字迹的可行性。方法收集了市场上常见5个品牌不同颜色和批次的49种热敏可擦签字笔和5种普通签字笔,运用显微红外光谱ATR方法对其书写字迹进行检验,同时考察了纸张对字迹红外谱图的影响。结果49种可擦笔字迹样本均在2916、2850、1729、1513、1455、1254、1214、1170、830、739、698cm-1附近有较强吸收峰;不同品牌相同颜色可擦笔字迹的红外吸收峰的位置和强度存在明显区别;同一型号不同颜色字迹样本的红外吸收峰和吸收强度亦存在明显差异。结论显微红外光谱ATR方法分析可疑字迹,既可鉴别其是否为伪造字迹,又可认定伪造所用的可擦笔品牌。该方法具有快速、无损和准确的优势,为伪造文件中可擦笔字迹的检验提供了一种有效的技术手段。

Objective To explore the feasibility of identifying the writings with their componential identity from thermosensitive erasable signing pens using microscopic attenuated total internal reflectional Fourier transform infrared spectroscopy(ATR-FTIR).Methods With a collection of 49 kinds of thermosensitive erasable signing pens(from color-and batch-different products of 5 various brands)and 5 brand-discrepant common signing pens,the writings were tested from the collected pens via microscopic ATR-FTIR.At the same time,the infl uence of paper was investigated on the infrared spectrum of writing.Results All the 49 erasable writing samples had one strong infrared absorption peak near the respective 2916,2850,1729,1513,1455,1254,1214,1170,830,739 and 698cm-1,revealing that those brand-different yet color-same erasable pens were shown of their writings into the peaks of obvious difference at both position and intensity.For those model-same yet color-different pens,their writing samples were also found of obvious difference with their infrared absorption peak and intensity.Conclusions The microscopic ATR-FTIR can identify not only whether one suspicious writing has been forged about its componential identity but also the brand of erasable pen used for forging.This method is of fast,lossless and accurate advantages,capable of providing effective means for the inspection of forged documents.