Core Functions and Technical Principles of Wetting and Leveling Agents in Waterborne Coatings

In waterborne coating systems, wetting and leveling agents are essential for preventing application defects. Chemi Tech’s agents utilize unique molecular designs to improve substrate wetting and film uniformity, with technical contributions spanning three areas:

Surface Tension Reduction & Substrate Wetting

Waterborne coatings exhibit high surface tension (～72 mN/m), causing cratering and edge retraction on substrates like plastics. Chemi Tech’s silicone-modified agents lower tension to 20–25 mN/m, achieving contact angles θ<90° for instant spreading. For low-energy substrates (e.g., PP), adding 0.1%–0.5% improves wetting efficiency by 40%, eliminating coating inhomogeneity.

Leveling Optimization & Defect Prevention

Dynamic surface tension control during application is critical:

Static Wetting: Rapid migration to interfaces within 20 seconds suppresses Benard vortices, avoiding orange peel;

Dynamic Wetting: Enhanced spreading under high shear (e.g., spraying) prevents fisheyes and pinholes. In PU systems, dynamic wetting efficiency exceeds conventional products by 30%.

Compatibility & Process Adaptability

Polyether-modified siloxane structures ensure compatibility with acrylics/epoxy resins without seeding or foam stabilization16. Short-chain designs (C8-C12) preserve intercoat adhesion for recoating. In high-solid coatings, 0.2%–0.8% additions balance leveling and slip properties7.

Chemi Tech offers tailored solutions:

Porous Substrates: Low-viscosity penetrants (<50 mPa·s) accelerate capillary action in wood grain;

High-Temperature Processes: Heat-stable variants maintain tension stability at 80°C for baked coatings.