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Water-borne cavity preservation optimised for dip application
A Bachelor’s thesis explores the adaptation of a water-based cavity preservation system for use in dip coating processes. Rheological measurements and formulation changes form the basis for further development.
In a Bachelor’s thesis submitted at Esslingen University of Applied Sciences, a water-based cavity preservation product was reformulated for use in dip-coating processes. Originally designed for spray application, the new formulation aims to replicate the optical, tactile and protective properties of a hotmelt reference system while enabling thick-film formation in submerged parts.
The study focused on formulation modifications and method development. Various dip trials on sheet metal were carried out to evaluate film formation, which is critical for subsequent corrosion protection tests. The researchers examined the material’s rheology to better understand how different ingredients influence film integrity.
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Impact of thixotropy and formulation components
Four experimental series were conducted, assessing the effects of wax-based metallic soaps, corrosion protection additives, additional formulation changes and thickening strategies. The results indicated that the time-dependent structural build-up—or thixotropy—of the formulation had a substantial influence on film retention during the dip process.
Metallic soaps were identified as the key thixotropic agents within the system. Formulations with slower structural recovery exhibited greater sliding and poor layer formation on the metal surface. Based on the test results, a baseline formulation was created to serve as the foundation for ongoing development.
The study provides a solid foundation for further adaptation of the water-based cavity preservation product for dip applications. The validated rheological data will support future optimisation work.
Source: Isabelle Kopp, Bachelor’s thesis, Esslingen University of Applied Sciences, 27 January 2025 (embargoed until 27 January 2030)
