Pollution Concerns Drive Market for Air-Cleaning Coatings

Rising concerns about air pollution in Europe are accelerating a swing among the region’s consumers to favoring coatings which help provide cleaner air.

Combatting climate change through reductions in emissions  of carbon dioxide (CO2) remains a matter of primary importance in Europe.  But mounting anxieties about poor air quality are beginning to overshadow concerns related to the dangers of global warming.

Coatings which   promote lower  levels of CO2 and other global warming gases tend also to help keep the air clean.  As a result these  coatings  are seen as having a  two-pronged  advantage.

Politicians and NGOs in Europe  have been pressing for  decreases in CO2  emissions and in air pollutants  to be given an equal  priority.

”There is little doubt that terrible levels of air pollution being suffered by people in many countries and cities around the world is finally pushing this issue up the political agenda,” said James Thornton, chief executive of ClientEarth, London, an international  environmental lawyers group. “This is a very real public health emergency. It is simply not acceptable that pollution is not being tackled as a major health issue.  If the water we drink was causing so many early deaths, we’d take immediate and urgent steps. The same should happen for the air we breathe.”

While  CO2  levels  have been falling in the region, air pollution figures in some of Europe’s major cities have been worsening due mainly to contaminants from automobile and truck fuels and from industrial plants.

Statistics from the World Health Organisation (WHO)  show that  air pollution in Europe could be causing as many  as 400,000 early  deaths  from respiratory conditions, heart  disease and certain cancers.  

These are being linked to impurities  in  street air such  as  particulate matter (PM), sulphur dioxide (SO2), nitrogen oxides (NOx), ammonium ( NH3), ozone  and carbon monoxide (CO)  and CO2.  Some of these  and other contaminants  are fouling the air inside  homes, offices and  other buildings.

Coatings producers are having to concentrate more on the development of formulations which are free from chemicals posing risks to public health through air pollution. 

These priorities were evident at the recent  European Coatings Show  at Nuremberg, Germany, where exhibitors were giving a high profile to issues of air quality.  

“Consumer perception of eco-friendliness is changing the behaviour of the paints industry  more and more,” explained  Daniet Bruenink, director global marketing for decorative paints  at Evonik, the German-based additives producers.  “Paints are being identified  as a source of (for example) indoor air  pollution  and customers are demanding healthy and sustainable  solutions.”

Formulators  are seeking ways of giving coatings additional functionalities such as methods of keeping surfaces clean because leaching of dirt can contaminate air.
Silicone-based polymers with hydrophobic and oleophobic properties can provide easy-to-clean effects that ensure dust, oil pen marks and wine  and coffee spills can be easily removed from coated substrates, according to Altana’s Byk Additives & Instruments business.

There  is also a robust  demand for paints with low odor, which is a quality inherent  in paints with low emissions of volatile organic compounds or without any VOC discharge.

In fact, across much of Europe there have  been strong increases in sales of coatings and ingredients with low emissions of VOCs or their complete absence. This  is perhaps evidence of  a combination of  concerns about both climate change and poor  air quality.

A survey of people attending the ECS Congress  found that the highest proportion – 20 percent – considered that  VOC emissions was the most important current regulatory issue.

Companies have been reporting sudden surges in sales for their low VOC or emission-free products, some of which have been on the market for a relatively long time.
“Demand levels at the moment show  a major trend in favour of low emissions paints,” saie Tomas Espana, Celanese’s acetyl chain account manager in Europe.   One  of Celanese’s main low-emissions products in Europe is a vinyl-acetate-ethylene (VAE) dispersion with  low emissions both of VOCs  and also semi-VOCs (SVOCs)  which because of their slow evaporation produce  emissions over a longer period of  time in building interiors.

Sales of low emissions  products have been boosted in Europe  by stipulations by national governments that coatings  carry eco-labelling indicated their levels of  VOCs  or even SVOCs.

“The rules on eco-labeling have changed the market in some countries for household items  like furniture and other products with coatings  whose products can affect  interior  air quality,” explained Espana.  “If your product  doesn’t qualify for a  an eco-label because its  coatings breach an emissions threshold  it will not get into some markets.”

Another clean-air product which also appears to be enjoying a suddent rise in sales is photocatalytic paint with the catalytic  ingredient mainly being titanium dioxide.  Most  TiO2  producers  in the European market  supply  grades  of the pigment which are photocatalytic.

They accelerate the degradation of organic pollutants  such as NOx, which are precursors to the formation of the particulate matter regarded as the most hazardous of contaminants to human health.

“Demand for our TiO2-based photocatalysts  are going up at a double-digit rate,” said  Heinz-Christian Krempels, technical manager, pigments and TiO2  specialities, Kronos International, Leverkusen, Germany. “The growth is fastest in Europe where the photocatalysts  are being applied in paints for exterior use such as on pavements, walls  and roofs but they are also being used in interior coatings  as well.”

Studies on the effectiveness of  TiO2  photocatalysts  in tackling air pollution have had mixed results.   The UK’s  Air Quality Expert Group (AQEG)  concluded in a  report last year they did not achieve  “significant reductions” in nitrogen dioxide concentrations mainly because large volumes of air would have to interact with the coated surface.

However  technologies  which increase the catalytic  potential of  TiO2  may be more effective.  The   TiO2 photocatalysts of Kronos , for example, are coated with a carbon dopant.  This  results in a 4 percent reduction in the air polluting emissions from  motor vehicles, which Kronos  claims in higher  than that of other TiO2  photocatalysts.

New  dopant  technologies  on both TiO2  and other  substances  could give  photocatalytic coatings even greater potential in the fight against  air pollution.  They are an example of new opportunities  being opened up to coatings producers by the desire among consumers  for cleaner air.