on supplies in the rest of the world would
have been even worse.
In the last two years, however, total imports into China of TiO2 feedstocks—
ilemnite, rutile and titanium—have at
least doubled, which has contributed to
the stress on supplies throughout the
global supply chain for the pigment.
TiO2 producers at the ECS were
claiming that uncertainties about the
availability of feedstocks supplies were
an obstacle to investment decisions in
new capacity in Europe.
Short-term supply agreements and
prices have now been extended to feedstocks as well as TiO2 itself. Feedstock
producers will only commit to delivery
deals covering 12 months rather than
three to five years as was the custom previously, while agreements on prices cover
only a few months.
The last new TiO2 plant to be built in
either Europe or North America was
around 20 years ago. It will probably be
at least a minimum of four to five years
before another one is constructed in either region. DuPont has said it is planning a brownfield expansion in the U.S.
over the next few years while other capacity increases will have to come from
debottlenecking.
With the prospect of a lengthy period
of high TiO2 prices, an incentive for coatings materials suppliers to offer ways of
reducing the pigment’s content in formulations is that they will be applied permanently rather than temporarily.
“Once coatings manufacturers have
worked out formulations with lower
TiO2 contents they will stick with them,”
said Frank Huskey, technical service man-
ager at KaMin, a performance minerals
producer in Macon, Georgia. “The rise in
TiO2 prices and the knowledge that the
increases will continue has made coatings
companies look much more carefully at
the efficiency of TiO2 in their formula-
tions. Previously when TiO2 prices were
at a lower level there was no motivation
to do that.”
The main means of decreasing TiO2
content is the improvement of spacing
and dispersion of the pigment’s particles
so that they operate more effectively in
the paint.
“On average only approximately 75
percent of TiO2 in a formulation is being
used effectively,” said Martin Fisher, Eu-
ropean specialty sales manager at the
Finland-based engineered materials busi-
ness of Huber Group of Germany. “The
remaining 25 percent is wasted because
the particles are too crowded and get in
each other’s way. To get the best per-
formance out of TiO2 particles they need
to be spaced at the right distance from
each other.”
Huber provides amorphous sodium
aluminosilicate particles for matt coatings
with a uniform size of around 0.3 microns
to act as ‘spacers’ for the separation of
TiO2 particles. They also have a light scat-
tering effect to provide opacity.
KaMin supplies ultrafine clay particles
of 0.2 microns in size as spacers to help
the dispersion of TiO2 within gloss paints.
The company says that with the aid of its
micro particles the TiO2 content of formulations can be reduced by as much as
30 percent.
While mineral particles act independently of TiO2 particles to keep the two
substances apart from each other, polymers have been developed to perform a
similar function but by binding themselves
to the titanium dioxide.
Dow Chemicals at the ECS launched a
polymer, which attaches itself to TiO2
particles to form a composite. This improves the dispersion of TiO2 and helps
prevent crowding so that it has greater
light scattering efficiency. The company
says it can reduce TiO2 in a formulation
by up to 20 percent while retaining similar opacity or hiding levels.
“Instead of using more TiO2 to im-
prove hiding, we looked at ways to make
it more efficient,” said Dave Fasano, a
Dow research scientist. “In effect we’re
making every particle of TiO2 work
smarter. That opens up a whole new range
of options that formulators do not have
with TiO2 alone.”
In fact highly priced TiO2 could bol-
ster R&D in an area of research in not
only the particle sizes of the pigments but
also their shapes and surface textures and
interaction with filler materials with the
aim of using less of the chemical but with
the same effect. CW
