26/10/2023
Water-borne industrial coatings are more environmentally friendly alternatives to traditional solvent-based coatings. Their popularity has gradually increased in industrial painting, where it is essential to minimize VOC emissions. Water-borne industrial coatings designed for metal surfaces offer users several advantages.
Water-borne industrial coatings are more environmentally friendly than traditional solvent-based coatings because they contain significantly fewer volatile organic compounds (VOCs). For example, the VOC content of a 50 vol-% solvent-based epoxy coating is approximately 450 g/L, but the VOC content of a counterpart (50 vol-%) water-borne epoxy coating is approximately 60 g/L. The use of water-borne coatings reduces air pollution and helps companies comply with established emission limits.
The low VOC content also makes water-borne coatings safer to use. With solvents replaced by water, the health risks of the products are significantly lower, and the fire hazard is substantially reduced. This is especially important for the health and safety of workers during the painting process.
The technology and formulation of water-borne coatings have evolved over the years, improving product performance and making them competitive alternatives to solvent-based coatings. Nor-Maali’s product development has noted that the technical performance of water-borne industrial coatings is at least on the same level with solvent-based products. Some products even surpass their solvent-based counterparts.
Water-borne coatings achieve the same corrosion protection properties as solvent-based coatings. For example, the ISO 12944-5 C3M category is achieved with the same 120 µm DFT with a water-borne epoxy coating as with its solvent-based counterpart.
When studying the weatherability of the water-borne coatings it can be stated that water-borne polyurethane coating withstands UV radiation at least as well as its solvent-based equivalent. This property is more influenced by the type of polyol and/or mixing ratio than by the thinner type of the coating.
Nor-Maali has developed and expanded its range of water-borne solutions in recent years. Currently, there is a diverse range of water-borne epoxy, polyurethane, and acrylic products suitable for paint systems in corrosivity categories C1-C5.
Nor-Maali has three water-borne epoxy coatings: the matt primer Epocoat Aqua Primer and semi-gloss direct-to-metal coating Norepox Aqua DTM for steel surfaces, and the semi-gloss Normafloor Aqua for concrete surfaces.
Epocoat Aqua Primer is suitable as a primer under both water-borne and solvent-based topcoats, and Norepox Aqua DTM can be used either as a single-coat or topcoat with both water-borne and solvent-based primers. Together, these coatings can build a paint system that fulfills the requirements of C5M corrosivity category with a 180 µm DFT.
Epocoat Aqua Primer is a water-borne epoxy primer with first-class technical features. The product is intended as a primer for painting systems in corrosivity categories C2-C5 and can be used with both water-borne and solvent-based topcoats. Epocoat Aqua Primer has 5 hours pot-life and can be overcoated with itself after just three hours and with polyurethane coatings after four hours (+23 °C).
Norepox Aqua DTM is a water-borne epoxy single- and topcoat. The product is recommended for use as a direct-to-metal coating in corrosivity categories C2-C4. Norepox Aqua DTM has 1.5 hours pot-life, and the paint surface is extremely smooth and stylish. Norepox Aqua DTM can be overcoated with polyurethane coatings. Norepox Aqua DTM has the environmental product declaration (EPD), and the product is approved as belonging to emission class M1 for building materials.
Normafloor Aqua is a water-borne epoxy coating intended for concrete floors. With this coating the applied surface is walk-on-dry on after just six hours (+23 °C). Working with Normafloor Aqua is pleasant because the product is almost odorless. Normafloor Aqua is a CE marked product, so it can be used as a concrete coating for all construction sites. The coating is also approved as belonging to emission class M1 for building materials, making it an excellent option for projects where building materials must be low-emission. The product has a pot-life of 1.5 hours. Recommended applications include floors of public places, warehouses, basements, garages, ice rinks, factories and paper machine halls.
In the range of water-borne polyurethane coatings, Nor-Maali’s product offering is represented by the glossy direct-to-metal coating Normadur Aqua DTM. Additionally, the product development department is currently finalizing a semi-gloss version of the coating.
Normadur Aqua DTM is a polyurethane single- and topcoat, with an aliphatic isocyanate as the hardener. The product is used as a direct-to-metal coating in corrosivity categories C2-C3 and as a topcoat in corrosivity categories C2-C5. Both water-borne and solvent-based products are suitable as primers. For example, a weather-resistant, low-VOC solution can be achieved in corrosivity category C4M together with Epocoat Aqua Primer. Normadur Aqua DTM’s blister-free thickness is about 200 µm DFT and it has a pot-life of 3 hours. Normadur Aqua DTM has been tested according to standard ACT Volvo STD 423-0014 (rev. 6) and it fulfills the requirements.
Nor-Maali offers both one- and two-component acrylic coatings. The one-component products include the matt primer Akvanor 81 Primer and the semi-gloss direct-to-metal coating Akvanor 100 SG. Nor-Maali’s latest water-borne product is the two-component semi-gloss direct-to-metal coating Norecryl Aqua DTM.
Akvanor 81 Primer is a water-borne, acrylic based anti-corrosion primer. As a one-component product, it is easy to use. Akvanor 81 Primer is suitable for corrosivity categories C1-C3 as a primer and it can also be applied on clean and undamaged shop primer or on old paint. Akvanor 81 Primer meets the Marine Equipment Directive 2014/90/EU quality requirements, and it is approved as belonging to emission class M1 for building materials.
Akvanor 100 SG is a water-borne, one-component acrylic based single- and topcoat. The product is suitable as a direct-to-metal coating for corrosivity categories C1-C3. Akvanor 100 SG has been tested according to standard ACT Volvo STD 423-0014 (rev. 6) and it fulfills the requirements. Additionally, the product meets the Marine Equipment Directive 2014/90/EU quality requirements, and it is approved as belonging to emission class M1 for building materials.
Norecryl Aqua DTM is a 2-component acrylic single-coat which combines the corrosion resistance of epoxies and the weather resistance of polyurethanes. This environmentally friendly direct-to-metal coating also ensures user safety as it contains no isocyanates. Norecryl Aqua DTM is designed as a direct-to-metal coating for corrosivity categories C2-C3. The product reaches corrosivity category C3M with a 120 µm DFT, making it an excellent choice for painting machinery and equipment and general steel structures. The paint has 8 hours pot-life, which is long compared to many polyurethane coatings.
Nor-Maali’s water-borne industrial coatings represent a new generation of surface treatment technologies that combine environmental friendliness, user safety, and excellent performance.
For more information on water-borne coatings, contact Nor-Maali sales.