Fouling Analysis on Surfaces
Cleaning processes are indispensable in the production of almost all industrial goods. Complex cleaning processes are often used to remove contamination from surfaces. The contamination may be present in the form of spots, films or particles and is generally known under the term “fouling”. For the manufacturing process of various goods and components, the removal of fouling is of great importance to ensure the quality of either subsequent processes (e.g. paint coating, electroplating, and hardening) or the purity of the end products. In order to check the success of cleaning processes, surface analysis tests are required. In the Tascon laboratory, we use fouling analysis to identify, localize and quantify contaminations such as particulate contamination or contaminant films on components.
In the following, the surface analysis of an optical filter is used to illustrate the contribution that modern surface analysis methods can make when optimizing cleaning processes and in the analysis of fouling.
Fouling analysis using ToF-SIMS imaging
Optimization of cleaning processes
The result of cleaning processes that take place in the course of the production of optical filters was investigated with the help of secondary ion mass spectrometry (ToF-SIMS). Static ToF-SIMS analyses were carried out to determine the chemical composition of the glass surfaces before and after cleaning. Before cleaning organic contaminations such as triglycerides and dodecyl benzene sulphonate were identified with ToF-SIMS on the specialty glasses in this fouling analysis. After wiping the optics with acetone at the end of the cleaning, the proportion of these substances was significantly reduced. Nevertheless, adhesion problems were observed in the subsequent coating of the glass surfaces. Therefore, the lateral distribution of organic residues on cleaned glass surfaces was analyzed in a second analysis step by imaging on fields of view of 60x60 mm² ("macro scan").
The secondary ion images shown here demonstrate that salts of dodecyl benzene sulphonate and oxygen-containing hydrocarbons can be detected locally even after the cleaning procedure. Based on this and other data, the dripping and wiping with acetone was identified as a weak point and replaced by a more effective cleaning step. Thus, the cause of the contamination could be clarified at Tascon in the laboratory for fouling analysis.
Tascon - your partner for professional fouling analysis
Do you need support with the fouling analysis of your surfaces? Contact Tascon. We support you in discussions with customers and suppliers. Let our experts advise you.