DOWSIL™ 904H Paint Additive for Exterior Facade Paints

Reduced surfactant leakage for better resistance to "slug trail" effect and improved surface water repellency.

DOWSIL ™ 904H Paint Additive Key Benefits • Reduced "Slug Trail" effect, • Improved water resistance, • Improved water repellency, • Improved water retention (Greater water contact angle [WCA]).

Enhanced Aesthetics for Exterior Facades

The aesthetics of building exterior facades are increasingly gaining importance worldwide. Architects and building owners are moving away from white/grey tones and using darker and striking bright colours as design elements. When these colours dry after application in cold and humid air conditions, surfactants and other water-soluble compounds can leach onto the surface and cause a visual effect known as "slug trail". "DOWSIL ™ 904H Paint Additive" addresses this problem and reduces the slug trail effect.

Better Surface Properties

DOWSIL™ 904H Paint Additive was tested in various exterior facade formulations where it demonstrated positive effects in reducing slug trails under different evaluation methods. Both the draw-down test and the cup test yielded positive results. At the same time, this silicone additive can also improve surface water repellency through improved water resistance and better water retention (greater water contact angle [WCA]). Compared with conventional water repellency, DOWSIL ™ 904H Paint Additive demonstrates superior performance in reducing slug trail effect.

A Major Contribution to Formulation Flexibility

There are many approaches to minimizing a paint's susceptibility to slug trail effect. The first option is to reformulate based on a special, often water-repellent binder. The second is to reconfigure the dispersing agent package to minimize the amount of water-soluble materials. Both approaches can be effective, but will likely be complex and time-consuming. A third option is to use additives. Adding 2 to 5% active level DOWSIL ™ 904H Paint Additive to an existing formulation offers a simple way to minimize slug trail effect.

Figure 1. Slug Trail Evaluation Using Draw-Down Test

2% active DOWSIL™ 904H Paint Additive was added to an exterior facade wall paint formulation based on PRIMAL™ SF-016 ER Acrylic Solution (51% PVC level).

Figure 2. Slug Trail Evaluation Using Cup Test

Exterior facade wall paint formulation (55% PVC level) with 5% active DOWSIL™ 904H Paint Additive added.

Figure 3. Improved Water Retention (WCA)

2% active DOWSIL™ 904H Paint Additive was added to an exterior facade wall paint formulation based on PRIMAL™ SF-016 ER Acrylic Solution (51% PVC level).

Figure 4. Improved Water Resistance – Early Water Absorption

1% active DOWSIL™ 904H Paint Additive was added to an exterior facade wall paint formulation based on acrylic-modified VAE solution (50% PVC level). Compiled by: Başak Nur Mert Sales Representative UnivarSolutions