Europe
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 giv-
ing coatings additional functionalities
such as methods of keeping surfaces
clean because leaching of dirt can con-
taminate 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 combi-
nation 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 cat-
alytic ingredient mainly being titanium
dioxide. Most TiO2 producers in the
European market supply grades ofthe
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 pho-
tocatalysts are going up at a dou-
ble-digit rate,” said Heinz-Christian
Krempels, technical manager, pig-
ments 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) con-
cluded in a report last year they did not
achieve “significant reductions” in nitro-
gen dioxide concentrations mainly be-
cause 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 per-
cent reduction in the air polluting emis-
sions 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 po-
tential in the fight against air pollution.
They are an example of new opportuni-
ties being opened up to coatings produc-
ers by the desire among consumers for
cleaner air. CW
“Formulators are
seeking ways of
giving coatings
additional
functionalities such
as keeping surfaces
clean because
leaching of dirt can
contaminate air.”
