Zero Rust dries to touch in 30 minutes and is tack-free within one hour, depending on the relative humidity and temperature. Drying time can also be affected by film thickness, flash off time between coats, amount of thinning, and temperature. Normally, commercial topcoats may be applied within 24 hours or after solvents have evaporated. Zero Rust is compatible with a wide variety of commercial topcoats. For particular applications, contact your technical representative.
Urethanes containing acetone, however, make top coating air-dry finishes more difficult.
Our testing shows that, because acetone is an aggressive paint stripper, it can soften and wrinkle or lift the undercoat, thus shortening the lift-free window. It requires more precise timing when topcoating with low viscosity urethanes that contain acetone or that are thinned with acetone. A 4 mil wet film of Zero Rust can be topcoated within 3 to 6 hours with minimal solvent trap problems. If you are unable to apply the topcoat within this time frame, it is advisable to wait 24 hours before top coating. Additionally, applying a light bridge coat of the urethane before the flood coat will help stop solvent dive-in, which can cause lifting and wrinkling of the Zero Rust.