红外光谱结合化学计量学方法在激光打印原装黑色墨粉分析中的应用研究

目的 采用红外光谱比较分析不同原装黑色墨粉（31个样本）的差异,探讨化学计量学方法在墨粉种类识别中的适用性.方法 对打印样本纸张上的黑色墨粉进行烫熨提取后直接分析检测.IR分析条件：显微红外光谱仪,常温透射模式,扫描范围为4 000～400 cm-1,分辨率为16cm-1,累计扫描次数为64次.结果 墨粉树脂主要为聚苯乙烯/甲基丙烯酸甲酯和聚对苯二甲酸/环氧树脂.采用主成分析（Principal Component Analysis,PCA）与系统聚类法（Hierarchical Cluster Analysis,HCA）对不同种类墨粉进行聚类分析与建模预报.基于前两主成分得分值（53.3％）不同树脂成分的墨粉样本聚类效果明显,同时在第三个主成分方向上黑白与彩色激光墨粉样本获得良好区分.结论 红外光谱法结合化学计量学方法用于不同种类树脂及打印类型原装黑色墨粉的聚类分析与建模预报方法可行,结果准确可靠.

Analysis of Original Black Toner of Laser Printers by Infrared Spectroscopy Coupled with Chemometrics

Objective to compare the difference between 31 different original black toner samples using infrared spectroscopy （IR）. The applicability of chemometrics as a viable method in the discrimination of toners is explored. Method Toner samples were directly analyzed after being extracted from paper. Transmission spectra were collected using microscopic infrared spectrom- eter at room temperature, with a resolution of 16 cm-. The wave range was from 4000 to 400 cm- and 64 scans were accumulated for one spectrum. Results The toner samples are mainly composed of polystyrene methyl methacrylate and terephthalate/epoxy resin. The difference and relationship between the toner samples were analyzed with the principal component analysis （PCA）and hierarchical cluster analysis （HCA）. The samples containing different resins were classified into two groups with the first two principal components which explained approximately 53.3% of total variation of the spectral data. In the third principal compo- nent direction, the samples from monochrome and color laser printers were well distinguished. Conclusion It is demonstrated that the IR coupled with chemometric method is an effective tool for the rapid discrimination of black toner in forensic practice.