Crodacor OME FE Maximize the corrosion defense of your waterborne coatings

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1 Crodacor OME FE Maximize the corrosion defense of your waterborne coatings Croda Coatings & Polymers your natural choice

2 Crodacor TM OME FE Maximize the corrosion defense of your waterborne coatings Maximize your corrosion defense The trends of moving from solvent to waterborne paints and reducing the number of coatings on mild steel have brought new issues regarding corrosion resistance. Protection against flash rust and long term corrosion currently requires multiple additives. Crodacor OME FE is a novel additive that combines corrosion and flash rust protection for mild steel acrylic and alkyd coatings, simplifying aqueous formulations. Features and Benefits l Superior long term corrosion resistance and flash rust protection l No negative effect on other performance properties l Addition at different stages in production l Excellent environmental profile (no HAPS, no VOC) Flash rust performance - Acrylics Flash rust is the development of corrosion within minutes after application of a waterborne paint onto a steel substrate and migration of the corrosion products through the paint to the surface. Flash rust is a common problem associated with waterborne direct-to-metal (DTM) paints. Figure 1 shows that panels coated with a direct-to-metal (DTM) acrylic paint plus Crodacor OME FE (at 2% weight loading) exhibits no flash rusting throughout the panels. The control DTM paint and the DTM paint with a competitive corrosion inhibitor showed flash rusting throughout the panels, with minor differentiation between the two. All panels were 3 mil drawdowns. Control Competitive corrosion inhibitor (2%) Crodacor OME FE (2%) Figure 1: Flash rust results of a DTM paint after 1 hour Croda Coatings & Polymers your natural choice

3 Long term corrosion performance - Acrylics General purpose DTM paint A DTM general purpose acrylic paint was sprayed (5.0 mils) on mild steel Q panels. Other panels were made (3.2 mils) with the same paint containing 2% of either Crodacor OME FE or a traditional corrosion inhibitor. After 370 hours of continuous 5% salt fog exposure, the panels with 2% Crodacor OME FE showed fewer corrosion products and less blistering than the control and the competitive material. Figure 2 shows the results of these tests. Control Traditional corrosion inhibitor (2%) Crodacor OME FE (2%) Figure 2: DTM general purpose acrylic paint after 370 hours of continuous 5% salt fog exposure DTM primer Panels unscribed and scribed with a DTM acrylic primer were subjected to 500 hours of continuous 5% salt fog exposure. As seen in figure 3, the unscribed panel with Crodacor OME FE showed almost no corrosion products and no blistering compared to the panel with the traditional corrosion inhibitor. The scribed panels in figure 4 demonstrate that the primer with Crodacor OME FE showed fewer corrosion products and less blistering compared to the primer with the traditional corrosion inhibitor. Traditional corrosion inhibitor Crodacor OME FE Traditional corrosion inhibitor Crodacor OME FE Figure 3: Unscribed DTM primer spray-applied panels after 500 hours 5% salt fog exposure Figure 4: Scribed DTM primer spray-applied panels after 500 hours 5% salt fog exposure

4 Improved corrosion protection - Alkyds The results in figure 5 were obtained with waterborne alkyd formulations. Tests were done on cold rolled steel with an average paint thickness of 3 mil. Photos were taken after 672 hours in a 5% salt fog chamber. Formulation details are shown in figure 6. Competitive product (6%) (Recommended level) Crodacor OME FE (6%) Crodacor OME FE (3%) (Recommended level) Figure 5: Waterborne alkyd formulations after 672 hours 5% salt fog exposure The scribed panel with the competitive product shows more blistering than both Crodacor OME FE formulations. Crodacor OME FE at 6% shows less red rust in the scribed area, but more blistering than Crodacor OME FE at 3%. Less blistering on the panel is preferred over less red rust, as blistering indicates delamination and corrosion of the substrate under the paint, i.e. filiform corrosion. Red rust in the area of the scirbe indicates corrosion only in the area of the scribe and not under the paint. Therefore, the recommended use level of Crodacor OME FE is 3% on total formulation - which is 2% on actives, as Crodacor OME FE is 63% active. No need for additional flash rust inhibitor None of the panels had flash rust issues. The formulations in figure 6 show that Crodacor OME FE can replace the strontium zinc phosphate corrosion inhibitor and the flash rust inhibitor, giving improved short and long term corrosion protection to formulators with only one additive instead of two.

5 Starting Formulation The formulation in figure 6 is an alkyd emulsion corrosion resistant paint based on Pigmentan s WB-60-2 formulation ( Crodacor OME FE can be used at a 50% decreased use rate compared to the industry standard corrosion inhibitor. Furthermore, an additional flash rust inhibitor is not needed when using Crodacor OME FE. Ingredient Formulations (in grams) Competitive (6%) (Recommended level) Crodacor OME FE (6%) Crodacor OME FE (3%) (Recommended level) Grind DiH 2 O Zephrym PD Byk Acrysol RM Strontium zinc phosphate corrosion inhibitor 18.0 Crodacor OME FE Kronos TiO Letdown Beckosol AQ Co Drier Zr Drier Ca Drier Nitrite based flash rust inhibitor 1.0 Acrysol RM Figure 6: Formulations of DTM Alkyd Emulsion Paint Zephrym is a trademark of Croda. BYK is a trademark of BYK-Chemie. Acrysol is a trademark of The Dow Chemical Company. Kronos is a trademark of Kronos. Beckosol is a trademark of Reichhold.

6 Europe Asia Pacific Latin America USA For more information please visit: The information in this publication is believed to be accurate and is given in good faith but no representation or warranty as to its completeness or accuracy is made. Suggestions for uses or applications are only opinions. Users are responsible for determining the suitability of these products for their own particular purpose. No representation or warranty, express or implied, is made with respect to information or products including without limitation warranties of merchantability or fitness for a particular purpose or non-infringement of any third party patent or other intellectual property rights including without limit copyright, trademark and designs. Any trademarks identified herein are trademarks of the Croda group of companies C&P/US/01-14/DD