Paint & Coatings Industry - November 2008 - (Page 46)

Novel, UV-Curable ovel coatings were derived from a new approach to the selection of 100% solids polymerizable oligomers and monomers together with specific nano-material additives. The coatings exhibit unique property combinations and dramatically reduce water transmission and gas permeability on low-cost porous substrates. For example, gas transmission was reduced up to 200 times and water transmission was virtually eliminated on filter paper. In addition to many uses on current OEM products, the technology provides a platform for new products in electronic, packaging and label materials. Nanotechnology- N Background Formulation Alternatives In comparing the potential of various systems, each presents basic features that need to be considered in selecting the optimal target. Specifically, liquid systems of any kind are broadly composed of a combination of a film former (resin or latex), pigments (for color and hiding), additives (viscosity control, anticorrosion, etc.) and a vehicle (water or hydrocarbon solvents) to disperse the former, as shown in Figure 1. Since many resins are not compatible with water, their use as a vehicle is limited to emulsions such as latex or waterreducible systems that use a co-solvent (organic) to achieve water compatibility with limited resins. In all cases, a compromise is required between application and film performance requirements that can lead to high-viscosity (difficultto-apply) products requiring heating of the coating (and pump lines) for proper use. This occurs since relatively high-molecular-weight resins such as polysilanes, epoxies and polyurethanes that incorporate functional groups are commonly used to achieve the requisite combination (hardness, flexibility, moisture or chemical resistance, etc.) of cured film properties. An alternative is provided with two-package reactive systems that allow lower viscosity for ease-ofapplication. However, these systems commonly use crosslinking materials in a second package that may pose inhalation hazards requiring personal protection with air-supplied respirators during use. Solvent emissions are often associated with the great majority of the above-mentioned systems. Many require elevated temperature baking cycles to force dry the coatings in order to avoid the long production lags common with air drying. Moreover, any solvents emitted usually require afterburners for incineration. Incineration creates a secondary source of carbon emissions in the form of carbon dioxide; such emis- The great majority of the coatings supplied to the $6 billion global OEM product finish market are comprised of solvent-based coatings, water-soluble (latex or water-reducible) coatings, electrodeposited coatings, and powder coatings. A substantial number of the formulation changes in these systems since the 1970s has been driven by legislated requirements to substantially reduce VOC emissions. Powder coating use has grown dramatically since that approach eliminates VOC emissions. High-solids, solvent-based systems were developed along with improvements in water-based coatings to reduce VOC levels. UV-cured coating systems were emerging and taking significant market positions in wood flooring, fiber optic cable and photo-lithographic applications. Nevertheless, while these advances served to mitigate VOC emissions, none provided the advantages in terms of both VOC elimination and substantially lower energy requirements. For example, although powder coatings eliminate solvent emissions, substantial energy is required to fuse the powders, and the substrate must have enough conductivity to allow electrostatic application of powder. The research that culminated in the development of the technology described herein was originated in the early 1990s when the founder of the company (Sally Ramsey) began the search for an alternative to the conventional coatings of the day. The original development premise, which is still true today, was to (1) use no solvents except reactive components, (2) use no HAPs, (3) minimize energy requirements and (4) minimize plant floor space use. By F. Thomas Krotine and Sally J. W. Ramsey | Ecology Coatings Inc., Akron, OH 44 NOV EMBER 2008 | W W W . P C I M A G . C O M http://WWW.PCIMAG.COM

Table of Contents Feed for the Digital Edition of Paint & Coatings Industry - November 2008

Paint and Coatings Industry - November 2008 Contents Viewpoint Industry News Calendar of Events Company News Mergers and Acquisitions Names in the News HiTone Resins for Enhanced Pigment Affinity of Powder Coatings New Water-Based Interior Coatings Combine Innovation and Quality With Respect for the Environment Novel, UV-Curable Nanotechnology-Enabled Coatings Highly Weather-Resistant Radiation-Curable Monomers and Oligomers for Exterior Applications Konica Minolta — Sensing Success for Viracon Self-Crosslinkable Thermosetting Acrylics for Use in Water-Dilutable Coatings Paint and Criminal Forensic Science Supplier and Application/Curing Showcases Materials Watch Classifieds Advertiser Index

Paint & Coatings Industry - November 2008

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