Coatings for Africa, which took place from 21 to 23 May at Gallagher Estate, focused on the latest trends in the coatings industry. Technology and innovation was at the order of the day.
Coatings for Africa, which took place from 21 to 23 May at Gallagher Estate, focused on the latest trends in the coatings industry. Technology and innovation was at the order of the day. Walls & Roofs looks at key trends for environmentally-friendly water-based decorative paints.
In his presentation, “Formulation of environmentally-friendly paints”, Jay Udith from Sancryl Chemicals explained why some chemicals are hazardous. He also looked at eco-friendly paints that are commercially available, as well as ways to formulate a holistic eco-friendly water-based decorative paint.
With the emerging eco-friendly trend over the last ten years, the water-based decorative paint industry was forced to follow suit, he noted. Udith noted that the advent of the European Decopaint Directive of 2004 saw Western countries taking a leap towards eco-friendly compliance – but only in terms of volatile organic content (VOC).
Udith explained that in order to formulate the ideal environmentally-friendly water-based paint, the paint formulator must eliminate the use of raw materials that contain specific hazardous chemicals. “By understanding the true meaning of eco-friendliness, one can implement the practices that will lead to healthier living for the planet and its inhabitants, big and small,” he told delegates.
The true meaning of eco-friendly
“Eco-friendly literally means earth-friendly or not harmful to the environment,” Udith noted. This term most commonly refers to products that contribute to green living or practices that help to conserve resources like water and energy. Eco-friendly products also prevent contributions to air, water and land pollution, and do not have a negative impact on life.
Udith pointed out that environmentally-preferable coatings should:
• Have low toxicity levels.
• Be minimally polluting.
• Either be made with or offer energy-efficiency.
• Be safer and healthier for consumers, workers and the environment.
• Have a higher recycled content.
• Be packed in less packaging material.
• Be biodegradable.
Formulating a holistic eco-friendly paint
“When one wants to formulate a holistic eco-friendly paint, one must keep both environmental and human safety in mind. Current paint formulations contain various components that have been identified to be hazardous to the environment – termed grey products,” he said.
The number or type of these chemicals may differ, depending on the formulation used. “However, it is obvious that one cannot formulate an eco-friendly paint simply by removing just one of these component, but it must rather be a summation removal of all hazardous components,” he commented.
Alkyl-phenol ethylene oxide (APEO) free
Alkyl-phenol ethoxylate surfactants are usually made from a branched-chain nonylphenol or octylphenol reacted with ethylene oxide. These surfactants are used in a variety of industrial processes, including use in coatings as a wetting agent. The most common to our industry is the notorious NP 9 – now banned in most European countries.
Volatile organic compounds (VOC ) free
Volatile organic compounds emitted into the atmosphere have been associated with the production of tropospheric ozone and other gasses that have a negative impact on human health and agricultural production.
According to European legislation, a VOC is defined as any organic compound that has an initial boiling point less than or equal to 250ºC measured at a standard atmospheric pressure. The VOC’s in paints are normally attributed to the coalescent and solvents. A VOC has high vapour pressure and low water solubility. This participates in atmospheric photochemical reactions that contribute to atmospheric pollution. Furthermore, it is known to cause many respiratory diseases in humans.
Volatile organic compounds in paints and varnishes are restricted by the European Directive 2004/42/EC.
Heavy metal free
Heavy metals form poisonous soluble compounds and have no biological role – they are not essential minerals. Heavy metals, such as lead and mercury, are normally found in the pigments and additives of paint. Other metals, such as cobalt, cadmium, copper and zinc, are still useful in coating systems.
One of the largest problems associated with the persistence of heavy metals is the potential for bio-accumulation. Metals enter the bodies of animals and fish through the groundwater streams. Dry sanding of paints can also result in inhalation, where the metal enters the bloodstream through the lungs.
The heterocyclic chemical compounds, 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, are the active ingredients in biocide mixtures sold commercially. Studies have shown that CMIT and MIT are profoundly cytotoxic (cell-poisoning) to different types of cell lines, and MIT is reported to be a highly selective neurotoxin. Europe is leading the way with a number of environmental regulations, most notably the Biocidal Products Directive and new hazard labelling.
Formaldehyde is a colourless, flammable, strong-smelling chemical that is commonly used as an industrial fungicide, germicide and disinfectant in the coatings industry. Formaldehyde is an irritant of the eyes and respiratory tract – it causes both primary and sensitisation dermatitis. The International Agency for Research on Cancer has classified formaldehyde as a known human carcinogen. The no-effects level for formaldehyde is .018PPM, with minimal effects evident at exposure values approaching .05PPM.
Ammonia can take the form of a strong-smelling liquid or gas. Even in low concentrations, inhaling ammonia or exposure to it can cause burning, fainting or death. Ammonia interacts immediately upon contact with available moisture in the skin, eyes, oral cavity, respiratory tract and particularly mucous surfaces to form the very caustic ammonium hydroxide.
Best of both worlds
“A common misconception among many paint formulators is that caring for the environment must be at the expense of paint cost and performance,” Udith commented. It is also believed that environmentally-friendly alternatives are very expensive, he added. “When a paint formulator uses the range of products, it allows him to formulate paints to reduce the ecological footprint and helps developing sustainability of products for the future.”
Full thanks and acknowledgement are given to Coatings for Africa and “Formulation of environmentally-friendly paints” by Jay Udith for providing the information to write this article.