Catalyst Selection for Two-Component (2K) Polyurethane Automotive Refinish Clearcoats: A Comprehensive Review Abstract: Two-component (2K) polyurethane clearcoats are widely utilized in automotive refinishing due to their superior durability, gloss retention, and resistance to environmental factors. The performance of these clearcoats is critically dependent on the catalyst employed to accelerate the isocyanate-polyol reaction. This article provides...