Classification of ToF-SIMS detected chemicals causing nearly 1000 automotive paint craters

Abstract

When paint is applied to a substrate, the formation of paint craters is generally due to dewetting caused by a low surface energy substance present, such as siloxanes or perfluorocarbons, either on the substrate or in the paint that is applied to the substrate. As paint cratering is a surface phenomenon, the causing chemicals can be minimal both in size and quantity, or more precisely, below the detection limit of many analytical techniques. In order to identify the chemical responsible for paint craters, a technique that is extremely surface sensitive, chemically selective and capable of imaging is required. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) perfectly fits all these analysis requirements, and for the past decade we have used ToF-SIMS to identify automotive paint cratering chemicals. This article categorizes the paint cratering chemicals for the past decade and their distributions in terms of the four seasons. The information presented is expected to benefit both painting engineers and defect analysts in understanding possible/potential chemicals causing automotive paint craters, which is a costly failure in car manufacturing.