High Performance at Low Use
Dow Corning® 67 Additive, Dow Corning® 500W Additive,
Dow Corning® 501W Additive and Dow Corning® 502W
Additive provide excellent wetting performance at low addition levels with
little or no influence on slip.
Achieving excellent wetting without affecting slip properties is particularly
important for wood floor coatings, and Dow Corning® brand
superwetter additives provide the necessary performance. In a waterborne
PUD-based flooring coating, for example, all four additives provide excellent
wetting performance versus competitive organic and silicone wetting additives
over different substrates. The toolbox approach also enables formulators to
choose the right product for a specific application, while at the same time
reducing the number of products they must maintain in their raw material
portfolios. The superior performance can be measured in multiple waterborne
coatings by the surface appearance and coefficient of friction (Figures 1 and
Figure 1: Surface appearance and slip properties of a waterborne, PUD-based
wood coating with the addition of Dow Corning® 67 Additive,
Dow Corning® 500W Additive, Dow Corning® 501W Additive
and Dow Corning® 502W Additive. Additives were added at 0.2 weight
percent in the total formulation.
Figure 2: Surface appearance and slip properties of a waterborne,
acrylic-based wood coating with the addition of Dow Corning® 67
Additive, Dow Corning® 500W Additive, Dow Corning® 501W
Additive and Dow Corning® 502W Additive. Additives were added at
0.2 weight percent in the total formulation.
Multiple Options for Foam
Because wetting agents are surfactants, they promote foam generation to some
extent. The chemistry of the surfactant and the total formulation dictate the
level of foam generated. Important to the formulator is that this foam can be
controlled using foam control additives.
Dow Corning offers a range of antifoam additives to control any foam
generated when using this new family of wetting agents.
Figure 3: Example of performance of Dow Corning® antifoams when
formulated with surfactants: Dow Corning® 67 Additive is added at
0.4 weight percent into a flexographic gravure ink formulation. Antifoams were
added at just 0.1 weight percent in the total formulation. Foam height is
measured after high-speed shearing and is clearly vastly reduced with the
addition of both Dow Corning® 62 Additive and
Dow Corning® 65 Additive*.
Stable Wetting Performance at
The chemistry of silicone surfactants can often mean they are not stable in
higher pH formulations and performance is lost during storage of the coating or
Dow Corning 500W Additive, however, is ideally suited for higher pH
formulations and shows good wetting performance initially and on longer-term
storage. Other additives show high surface tension at pH 11, indicating
instability. With Dow Corning 500W Additive, surface tension remains
Figure 4: Stability of Dow Corning® 500W Additive as
demonstrated by dynamic surface tension stability over time in a pH 11
solution. Static surface tension remains consistent even after 1 month of