For a time, the U.S. lagged behind Europe and other parts of the world in developing eco-friendly coatings. In 2005, however, the House of Representatives passed the Green Chemistry Research & Development Act. Though the bill did not ultimately become law, it increased awareness of green chemistry practices and foretold an era of environmental consciousness in the industry. If green coatings are becoming the new normal, it’s due as much to consumers’ increasing savvy as to federal policy. Together, these forces continue to drive innovation.
Green coatings are nothing new, of course. Ancient Egyptian, Asian, and European cultures mixed raw natural pigments like turmeric with plant oil or egg yolk to make paint. Then, as now, its function was twofold: decoration and protection. The early 1900s saw the dawn of mass production, which involved not only pigments and binders but also additives and solvents, which inevitably included volatile organic compounds (VOCs). VOCs can lead to smog formation in cities and nausea, headaches, and even long-term health problems in people. Until 1960, paint could theoretically contain as many VOCs, and as much lead, as manufacturers preferred to use.
Paint’s unregulated status began to change in the mid-’60s. In 1966, in an effort to battle rampant air pollution, Los Angeles instituted Rule 66, a policy limiting VOCs in coatings and solvents. This was followed in 1967 by the Clean Air Act, a federal measure that echoed L.A.’s groundbreaking law. The government updated the CAA in 1990, adding a list of 189 toxins that had to be reduced in the environment. At the same time, the Environmental Protection Agency listed pollution sources by area and indicated which carbon compounds didn’t produce smog, and were thus exempt from VOC regulations.
While government restrictions are often thought to stunt creativity, the aforementioned laws prompted a great deal of new, forward-thinking research. The coatings industry’s four main avenues of exploration were water-based, powder, high-solid, and radiation-curable coatings. Of these, water-based coatings became and remain the most popular green coating type in the U.S.
In 1992, Glidden Company produced the first VOC-free coatings. They cost more than conventional coatings, and consumers largely ignored them. Other innovations weren’t far behind, however. Petroleum-based monomers – a key ingredient in paint film – could be replaced, it seemed, by monomers derived from castor or soy oil. And though vegetable oil sometimes produced paint that yellowed or didn’t weather well, it was at least inexpensive and abundant.
Since the government had no immediate plans to develop universal criteria for green coatings, nonprofits rose to the challenge. Green Seal is probably the best known; others include Environmental Home Center; Building Green, whose “Green Spec” directory lists eco-friendly products online; and the U.S. Green Building Council, creator of LEED certification, which considers materials and indoor environmental quality, among other factors. Green Seal’s GS-11, a standard for regular paint, looks at a product’s overall environmental performance, not just its lifecycle. (More on that distinction shortly.) In addition, the EPA’s Green Chemistry Institute (GCI) works on eco-friendly initiatives and gives awards to other innovators in categories like “alternative solvent pathways.”
Europe’s VOC regulations differ from America’s in that they pay more attention to chemicals’ volatility than to their reactivity. Thus, some fast-evaporating solvents that pass muster in the U.S. are prohibited in the European Union, while substances with a boiling point above 250 degrees Celsius are exempt from regulation in the EU. The strictness of Europe’s policies puts pressure on the U.S. to enact similar measures. Due to the manpower, material and energy costs, and rising insurance premiums associated with conventional processes and products, the American coatings industry is also getting greener of its own volition.
One interesting recent trend-within-the-trend is sustainable chemistry. Whereas green chemistry demands total biodegradation of products (the “total environmental performance” perspective, referenced above), sustainable chemistry proposes recycling and/or reusing as solutions (the “lifecycle” approach). The chief advantage of the latter strategy? Lower costs. Currently, the International Center for Sustainable Chemistry is partnering with the EPA to look at cost-effective sustainable alternatives to traditional methods. The GCI, mentioned earlier, is also exploring sustainability.
In order to succeed in the marketplace, green coatings must perform as well as, and cost no more than, their conventional counterparts. Thanks to the sharp increase in consumer awareness during the last decade or so, many companies now develop eco-friendly products not because regulations require them to, but because it makes good business sense. The innovation certainly isn’t limited to our shores; in Brazil, a company called Braskem has invented a high-density polyethylene made from sugarcane-based ethanol. While green coatings clearly benefit the planet, they’re also a smart investment for manufacturers of every stripe.