Chemical discrimination of multilayered paint cross sections for potential forensic applications using time‐of‐flight secondary ion mass spectrometry

• DOI: 10.1002/sia.6509
• Publication Date: 2018-07-17T09:57:05Z
• Authors: Shin Muramoto; Greg Gillen; Eric S. Windsor
• Keywords: Time-of-Flight

Time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) equipped with a bismuth imaging source and an argon gas cluster beam (GCIB) was used to image polished cross‐sections of four automotive multilayer paint samples. Secondary chemical the individual layers possible after GCIB sputter dose (7 × 10 15 ) ions/cm 2 applied for removal polishing residue, at which point composition clear coats could be distinguished using principal components analysis. For differentiation coat chemistries, only peaks were necessary; C H 5 O + ( m/z 45.04), 9 NO 163.09), 11 177.10) that appeared fragments carbamate‐based coat, 7 95.09) strongly associated polyurethane‐based coat. Clear identification samples based on this short peak list highlights strength SIMS technique as potential forensic approach discriminate paints suggests many more variables included in multivariate statistical analysis differentiate wider range chemistries.