Abstract：In order to detect the road marking paint from the trace evidence in traffic accident scene, and to differentiate their brands, we use Tri-level infrared spectroscopic identification, which employs the Fourier transform infrared spectroscopy(FTIR), the second derivative infrared spectroscopy(SD-IR), two-dimensional correlation infrared spectroscopy(2D-IR) to identify three different domestic brands of hot melting reflective road marking paints and their raw materials in formula we Selected. The experimental results show that three labels coatings in ATR and FTIR spectrograms are very similar in shape, only have different absorption peak wave numbers, they have wide and strong absorption peaks near 1 435 cm-1, and strong absorption peak near 879, 2 955, 2 919, 2 870 cm-1. After enlarging the partial areas of spectrograms and comparing them with each kind of raw material of formula spectrograms, we can distinguish them. In the region 700～970 and 1 370～1 660 cm-1 the spectrograms mainly reflect the different relative content of heavy calcium carbonate of three brands of the paints, and that of polyethylene wax(PE wax), ethylene vinyl acetate resin (EVA), dioctyl phthalate (DOP) in the region 2 800～2 960 cm-1. The SD-IR not only verify the result of the FTIR analysis, but also further expand the microcosmic differences and reflect the different relative content of quartz sand in the 512～799 cm-1 region. Within the scope of the 1 351 to 1 525 cm-1, 2D-IR have more significant differences in positions and numbers of automatically peaks. Therefore, the Tri-level infrared spectroscopic identification is a fast and effective method to distinguish the hot melting road marking paints with a gradually improvement in apparent resolution.
[1] LU Chun-qing, HE Hong-yuan, JIA Yan-chao, et al(路春清, 何洪源, 贾艳超，等). Journal of Chinese People’s Public Security University Science and Technology)(中国人民公安大学学报·自然科学版), 2009，1: 18. [2] CHEN Qi, GAO Pei-bang, JANG Zheng-qin, et al(陈 祺, 高培邦, 蒋政勤，等). Forensic Science(刑事科学), 2011, 70: 59. [3] YUAN Xin-qiang(袁新强). New Chemical Materials(化工新型材料), 2014, 42(1): 59. [4] FENG Ji-min(冯计民). Application of Infrared Spectroscopy in the Analysis of Trace Material Evidence(红外光谱在微量物证分析中的应用). Beijing: Chemical Industry Press(北京: 化学工业出版社), 2010. 37. [5] SUN Su-qin, ZHOU Qun, CHEN Jian-bo(孙素琴, 周 群, 陈建波). ATC009 Infrared Spectral Analysis Technology(ATC009红外光谱分析技术). Beijing: Quality of China Publishing House, China Standard Publishing House(北京: 中国质检出版社, 中国标准出版社), 2013. 19. [6] ZHANG Yu-ting, NAN Jun, YU Hai-bin(张玉婷, 南 军, 于海斌). Tianjin Chemical Industry(天津化工), 2010, 24(5): 4. [7] WENG Shi-fu(翁诗甫). Fourier Transform Infrared Spectroscopy·Second Edition(傅里叶变换红外光谱分析·第2版). Beijing: Chemical Industry Press(北京: 化学工业出版社), 2010. 291. [8] WANG Yu, HE Qin-ling, LIN Zhong-xiang(王 宇, 何琴玲, 林中祥). Paint & Coatings Industry(涂料工业), 2010, 40(4): 73.
