“Because low-VOC paints tend to leave the film surface sticky or tacky, we provide specialty surfactants that migrate to the film surface and provide excellent anti-blocking performance,” he said.
Griffin Gappert, new product leader, coatings specialties, Ashland Specialty Ingredients said that rheology modifiers, defoamers, surfactants, biocides are being used in water based coatings.
“Additives are increasingly being used to deliver properties that were previously the domain of binders and pigments, including improved film properties, surface appearance and hiding,” he explained.
According to Benjamin Dupnik, global segment manager, coatings, Cabot Corp, water-based coatings represent the majority of architectural coatings and continue to slowly gain share in traditionally solvent-based applications such as automotive and industrial coatings. For applications where coatings are applied in the field, one of the most important environmental requirements is VOC reduction.
“For industrial applications where solvent capture is feasible, many believe that solvent-based systems have lower environmental impact due to the reduced energy use associated with the cure step,” he said. “Water-based coatings tend to require a lot more energy to cure than solvent based coatings.
“At Cabot, we tailor products to excel in performance and efficiency in different systems. Our EMPEROR 1800 carbon black is tailored for water-based applications, while our EMPEROR 1200 and EMPEROR 1600 treated carbon blacks are tailored for solvent-based applications.”
According to Laura Bittle, product manager-Americas, advanced organics, OMG Americas, Inc., water brings problems in terms of wetting, therefore pigment dispersants and rheology modifiers are key areas that need attention.
“Water based systems create unique challenges for foam control which require newly formulated additives,” she said.
In formulation additives, Dr. Shailesh Shah, Global Strategic Marketing-Formulation Additives, BASF Corp., said that BASF has focused on developing rheology modifiers that are specifically designed to work with new low VOC latexes, on developing dispersants that make very low VOC colorants possible, on developing wetting agents that optimize wet-adhesion in waterbased industrial paints and on developing defoamers that are particularly effective in near zero VOC paints.
“We also recently developed a series of novel light stabilizers, which target the low VOC water-borne coating market,” Shah said. “The Tinuvin-DW product series uses novel encapsulation of super durable light stabilizers for water-borne wood and plastic coatings. The increase in outdoor durability, especially for wood coatings, is significant.
Lastly, we recently developed ultra durable light stabilizers (Tinuvin CarboProtect and Tinuvin 479), which are key to enhanced coatings for the automotive and aerospace industries. They are mainly used in top coatins to protect the beauty of the finished part. They also exemplify how one can do more with less, if the right performance additive is used. With the Tinuvin Carboprotect, for example, a carbon-fiber reinforced composite part can last many years longer than with conventional coating technologies. With Tinuvin 479, we see better durability of polycarbonate used for headlights.”
According to Sel Avci, business development manager, Solvay Novecare Coatings, Solvay offers a full range of anionic and non-ionic surfactants, as well as specialty monomer technologies and defoamers for emulsion polymerization.
“Additionally, Solvay Novecare is a leading producer of APE-free and zero-VOC waterborne paint additives, which includes defoamers, wetting and dispersing agents, and the multi-functional additives for freeze-thaw improvement and extended open time,” he said. “Solvay Novecare also offers specialty amines, such as ethoxylated grades that can be used for pigment dispersion and as emulsifiers; green alternative coalescents and solvents;and other performance additives for waterborne, solventborne and UV-curable paint, coatings, inks and adhesive systems.”
Waterborne formulations are becoming more important due to tightening regulations and increasing consumer demand for more environmentally friendly products.
“Matching the performance of traditional solvent borne alternatives requires some changes in the formulator’s approach, including the use of additives such as corrosion inhibitors, pigment dispersants, wetting agents, defoamers, rheology modifiers, and emulsifiers,” said Patricia van eE, sales development specialist, Croda. “Croda’s additives address the challenges faced when creating high-performance water borne formulations, such as water resistance, flow optimization and foam control, corrosion inhibition and pigment dispersion.”
Bob Ruckle, global marketing and sales manager, Siltech Corp., explained that, considering only silicones, flow and leveling as well as slip and mar resistance properties are well understood and there is little need for new products targeting these properties.
“The focus on new waterborne coatings additives, as it has been for awhile, is defoamers and de-aerators,” he said. “The trick has always been to do this without impacting the coating properties. Recent macro trends like sustainability are being talked about but not yet affecting the choice of additives in a major way. The use of additives in a coating generally allows less solvent and better performance all improving sustainability.”