Market Watch
Pigments
Blue sky thinking from
ultramarine producers
Penetration of ultramarine pigments into the coatings market continues
Contact:
Colin Marson
Lisergy Consulting
T: +44 (0) 1162160292
E-mail:
[email protected]
Colin Marson
In a short survey of producers of ultramarine
pigments, Colin Marson, Managing Consultant of
Lisergy Consulting, a specialist coatings consultancy,
talks to two ultramarine pigments producers to
understand how they are developing products to
specifically meet coatings producer’s requirements.
U
Source: Nubiola
ltramarine blue pigments are a well established inorganic pigment in plastics and other applications,
but in coatings they have remained stubbornly a
niche pigment. But are things starting to change? Discussions with the producers of ultramarine pigments, Nubiola, based in Barcelona, Spain and Holliday Pigments
based in Comines, France, provide some insights into the
product and its future in coatings.
The key producers of ultramarines for use in technical applications such as coatings and plastics are still European
in origin. Nubiola (owned by the Nubiola family) has a
capacity of 16,000 tonnes/year, with production facilities
at Llodio (Spain), Doicesti (Romania), Medellin (Colombia)
and Chennai (India). Holliday Pigments (previously Reckitts Colours) has been established for over 125 years and
now owned by Rockwood Holdings, Inc. The company
has one large ultramarine plant in Comines that services
all of its local and international business.
The use of ultramarine blue pigments in coatings has
previously been more of an aspiration than reality, with
fundamental issues of low colour strength and transparency (rather than hiding power), relegating it to a few
niche opportunities. But the key benefits of ultramarines
are now starting to be realized as new product developments are launched onto the market.
More than just a unique colour space
One of the key benefits of using ultramarine blue in
coatings is that it provides a unique red shade blue, unlike phthalocyanine, indanthrene or cobalt blues. So ultramarine blue provides an opportunity to give brands
or products a distinct and unique colour differentiation,
important in today’s highly competitive consumer and
industrial markets.
In other applications such as plastics, cosmetics and of
course artists paints, the use of ultramarine pigments is
fundamentally understood, with its unique colour shade
well established as part of the colour palette available to
designers, colourists and product developers.
High transparency
Another potential disadvantage of using ultramarine blue
is its transparency, but in some circumstances this can
be a considerable advantage. A perfect example is when
ultramarines are combined with effect pigments; you get
a combination that can exploit the unique shade as well
as its transparency.
The lack of hiding power is still an issue, but can of course
be compensated by use of titanium dioxide.
Whiter whites
More subtle uses of ultramarine blue are for whitening,
colour correction or shade alteration in greys. By absorbing yellow light creates “whiter whites”, in colour correction it can help achieve a match and in greys it can create
subtle blue undertones, that extend the shade options to
coatings producers.
From a technical perspective ultramarine blues (and violets) have excellent heat stability, light fastness and are
approved under food contact, toy and cosmetic regulations. By virtue of its inert raw materials and the high
temperatures it is exposed to during the production process, ultramarine blue has inherent heat stability.
This green profile is something Holliday Pigments and
Nubiola are keen to promote. Both have been active in
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Market Watch
Pigments
recent times registering ultramarines in compliance with EU Regulation 1907/2006, also known as REACH (Registration, Evaluation, and
Authorisation of Chemicals).
Alex Capuz,Global Marketing Manager of Nubiola states, “The “mild”
chemical nature of these pigments, i.e. a Sodium Aluminum SulphoSilicate, is definitively a guarantee of excellent “environmentallyfriendly” performance. We find this attribute has become more and
more important in today’s world.”
How is the use and perception of
ultramarine pigments changing in coatings?
The most popular uses of ultramarines in coatings currently are in
architectural (façade paints), decorative interior applications and
powder coatings. Other applications include motorbike/bike paints
and coil coatings.
Driving this change in perception are the two producers, Holliday
Pigments and Nubiola. Both these producers recognized a major gap
in the application of ultramarines in coatings and in the last 5 years
have developed products specifically for the coatings market.
Where before a generic ultramarine suitable for coatings was used,
now these companies have developed products specifically for
coatings.
Transparency has also been turned into a clear advantage. Again
particle size and distribution is the key, to achieving a similar refractive index to most resin systems. Combined with interference
pigments, ultramarine can create highly decorative and appealing
shades.
Left untreated, ultramarine is sensitive to acids and even mild acids
will attack the chromophore and destroy the colour, creating a chalking appearance. By applying a protective layer to pigment particles,
this improves weather fastness and enhances colour stability.
The coatings used to provide this enhanced performance are based
on silica encapsulation technology. This improved weather fastness,
has directly contributed to increasing exterior use and the resulting
grades have been particularly well received by customers operating
within emerging, high-tech market sectors.
What is the future for ultramarines in coatings?
Both global producers remain wholly committed to developing new,
added value solutions for customers and widening the application
scope for ultramarines. The key future development themes which
both companies agree, is further improvements in resistance to a
range of conditions, tinting strength and dispersibility
The acquisition of Holliday Pigments by Rockwood Holdings, Inc, has
also provided an opportunity to substantially increase Holliday Pigments’ existing research programme and extend its collaborative
arrangements with universities.
Nubiola also has a very active development programme, with products being tested for use in high quality lime paints (Venetian stucco). Stucco is becoming more popular as they use natural binders,
rather than synthetic oil-based materials. As lime paints have a high
level of calcium ions, any pigment needs to be highly resistant to
this aggressive environment.
The penetration of ultramarines into one of the largest pigment markets, coatings continues. As Capuz stated “ it is a process of progressively changing coatings company’s mindsets about ultramarine, as
much as developing new products”.
Whilst there is still some great challenges to gain the general use
of ultramarines in coatings, there is no doubt that their place is established and through new developments will continue to grow in
the future.
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www.european-coatings.com 01 l 2012 European Coatings J OURNAL