PFAs-Free surface finishing in the automotive sector: A comprehensive mapping of approaches for safety, sustainability, and functionality

Per- and polyfluoroalkyl substances (PFAs) have traditionally been used in automotive surface finishing applications due to their exceptional functional performance, particularly in the corrosion protection of metallic surfaces and in imparting easy-to-clean properties to plastics and glass. Increasing evidence of their environmental persistence, long-range transport potential and potential human and occupational health effects has intensified regulatory action and driven the search for safer alternatives. This ranges from existing REACH restrictions on specific PFAs, including PFOs, PFOA and long‑chain PFCAs, all of which belong to the PFAs class, to the ongoing broad PFAs restriction proposal.

Although OECD assessments indicate that PFAs-free coatings are commercially available, substantial gaps remain in understanding their hazard profiles, long-term stability, processability, and sustainability within automotive manufacturing. These information gaps hinder informed substitution and increase the risk of regrettable substitution.

The revised Safe and Sustainable by Design (SSbD) framework developed by the European Commission’s Joint Research Centre (JRC) provides a structured approach to integrating design and re-design, safety, sustainability, and functional performance in material and process development. However, explicit application of SSbD framework to PFAs-free coatings, particularly within the automotive coatings processes, remains limited in the literature.

This work provides a comprehensive overview of the current state of the art in PFAs-free alternatives for automotive surface finishing, with particular emphasis on methodologies (e.g., formulation strategies, application methods, and curing processes) that impact safety, sustainability, and technical performance, thereby influencing the feasibility of substitution. Existing literature and European initiatives were analysed to identify methodologies and strategies for the development and characterisation of PFAs-free alternatives, highlighting how these dimensions are addressed individually or in combination. Special attention is given to anti-corrosion coatings for metal substrates and easy-to-clean finishes for plastic and glass components, which represent high-impact applications where performance, safety, and sustainability intersect.

By mapping existing approaches and identifying knowledge gaps, this review aims to support future research and industrial development towards the design of safe, sustainable, and technically effective PFAs-free coatings. The findings underscore the need for holistic SSbD approaches that explicitly incorporate process-level considerations into the design and evaluation of next-generation automotive coatings.