Analysis of External Plastic Protective Sleeve of Wire by FTIR

21 plastic wire sleeve samples of 5 different colors were analyzed by FTIR.The characteristic peaks of samples including peak numbers, peak positions, and relative peak area ratios were observed in the spectra, they can be merged into two categories. In the FTIR spectra, different samples of the same color also reflect different information. This suggests that in the cases of plastic sleeves with vary close exterior colors using this method identification and comparison of various plastic products left on the crime scene can be effectively provided.