Microchemical Testing on Paint Samples in Forensic Science

Microchemial testing has been used in forensic science since the 1930s but has not been very popular in the analysis of paint samples. However, it is expected that microchemical testing would be a very viable examination for paint because it is relativity inexpensive, requires a small amount of sample, and produces reproducible and reliable results. This paper discusses two different methods of microchemical testing of paint samples, one on automotive paint, and the other on artistic paint. The method used for automotive paint consists of treating the sample with three reagents; sulfuric acid, nitric acid, and alcoholic potash. Observations are made of the reaction. The method used for testing artistic paint sample is a flow chart, where the identification of the paint can be determined by observing the reaction of the sample and performing the particular steps in the flow chart that follow. Known and unknown samples were analyzed for both sample types and are discussed based on ease of testing, cost of examination, time required for analysis, accuracy of results, and the amount of sample required. The results of the research determined that the method that was used to test automobile samples was not very successful, due to the time required, cost of analysis, and no positive identification of unknown samples. The artistic paint samples method was very successful. This was due to the low time required for analysis, the cost of examination being low, the small amount of sample that is required and accurate results obtained