How We Investigate: Paints and Polymers Subunit
Paints and Polymers Subunit
A visual comparison was made between the paint chips from the scene and the paint from the motorcycle. The Paints and Polymers Subunit (PPSU) of the Chemistry Unit attempted to physically refit the paint chips to the damaged area. This was done much in the same way as a jigsaw puzzle where pieces fit in a specific way. A microscope was used to evaluate the minute details of this “physical refit” between the paint chip and the paint on the motorcycle.
If there had not been a “physical refit,” the PPSU would have taken a paint sample from the motorcycle part near the area of damage and viewed the samples under a microscope to determine what the paint “looked” like. But, since the paints were consistent, the PPSU began to examine each layer of the paint from the scene and the motorcycle using various analytical methods. Every type of paint is made up of various components or “ingredients,” and two paints that are of similar color may not be of similar chemistry or make-up.
Because no discrepancies were noted between the two paints upon completion of the exams described above (visual, microscopic, instrumental), a positive result was reported. If at any point the paints were inconsistent, examinations would have been discontinued.