The topic of white ink is bandied about in just about
any conversation to do with wide-format printing these days.
Throughout the course of 2004, print providers heard OEMs and
suppliers, and more than a few publications, boast about white
ink developments on the way. But when these same print
providers arrived at trade shows throughout the year, they did
not see all that much white actually being printed, for one reason
or another.

All of which leads print providers to scratch their heads and
wonder, “What's up with white?” Does it exist or doesn't it? If so,
who really has it available now, and how soon can we get it? Why
has it been so hard to bring to market?

Why all the fuss over white ink in the first place? Primarily
because of what it can bring to the table. White can give colors an
added “pop” for packaging prototypes; it can add some bang to
backlits; and it helps expand media choices to include more clear
and dark substrates, as well as less-typical substrates such as
wood and metal. Further, and importantly, it allows digital printers
to compete with traditional screen printers, who have had
the capability of printing with white for some time now via
screen-printing technologies.

As of this writing, only a handful of wide-format printer manufacturers
seem to be currently offering white ink as a viable
option”?Azero, Durst, Eastech, and Mimaki. Of those, Durst
reports that they have more than 30 installed systems; in addition,
Aellora and Mutoh offer narrow-format white-ink inkjet
printers. Other printer manufacturers report that white ink is on
the drawing board or in some developmental planning stage.
We've charted those printer OEMs that have indicated they currently
have white-ink offerings or have something white in the
works on the next page.

Bringing it to market

Before delving into what applications might lend themselves to
white ink, and how additional profits can be made using it, you
may want first to understand why it has been so hard to bring
white ink to market. White ink carries with it a number of challenges
that printer OEMs and printhead manufacturers have had
to overcome, including: the ink's chemical structure; opaqueness,
workflow, and printer speed; and cost. Let's take a look at
each of these.

The molecule itself: The titanium dioxide particles that comprise
white ink are quite large, very dense, and abrasive. With
such a heavy molecule, it's difficult to keep it in solution (and
dispersed within that solution) long enough to spray it through
printheads. Part of this issue is not just the size of the particle,
but how much of the pigment is necessary to produce a good
white. To produce an opaque white, more pigment is required
than regular CMYK color, necessitating pigment loads up to four
to five times that of a normal color. More pigment in solution
compounds the problem of a heavy particle.
Because of the particle weight and the heavier pigment load,
the particles tend to settle quickly. Aellora Digital's Mario Carluccio
notes, “They will settle very quickly and form a layer that is
as solid as cement. This will permanently damage the inkjet
printhead and can occur within hours.”
Most OEMs have solved this part of the puzzle by designing a
stirring mechanism. The Rho and Eastech printers, for instance,
have recirculating pumps and “stirrers/mixers” within the ink
system to eliminate the settling of the titanium-dioxide molecules.
Aellora says it has solved the problem by creating a suspension
and developing dispersion techniques that don't require
stirring mechanisms.
With this very abrasive and heavy ink going through printheads,
does running white ink translate into more frequent
printheads changes? No, says Durst's Christopher Howard: In
the eight months that the Rho machines have been printing
white, he says, Durst users have not expressed any problems. Of
note is that Durst's white-ink printheads carry the same warranties
as its CMYK printheads.

Opaqueness, workflow, and printer speed: Where white ink
is involved, these three seemingly disparate issues are interconnected.
Let's begin with the question, should UV-curable white
inks be opaque or transparent?

Different jobs require different solutions; when spot white is
required, customers may need either opaque or transparent inks,
while white as an underprint or overprint usually demands opacity.

Does that mean that two inksets are required, one opaque
and one transparent? At present, OEMs with white ink offer only
one inkset”?opaque. That simplifies one problem, but presents
another: How can customers achieve transparent white inks?

The solution to the opaque/transparent problem is to educate
graphic designers to the nuances of white. Designers must
incorporate white into their designs”?using white as a fifth color.
If transparent colors are required, users must adjust the opacity
percentage in the white channel at the point of creation (in Photoshop,
Illustrator, etc.). If opaque white is necessary, the file
should be adjusted to reflect 100% opacity.

In addition, one of the biggest challenges in creating proper
files is determining if white prints at the same time, or before or
after CMYK. In the DuPont 22UV, for example, the white is printed
and cured in-line for white underneath and white standalone
applications; for reverse-white applications, the colors are
printed, and the white is then overprinted in a separate pass. One
way that Durst has addressed this problem is by giving its Rho
owners the option to specify the order of the printheads, depending
on the majority of their jobs, when purchasing the machine”?
white first for underprints; white last for overprints for backlits.

Will printing white slow down production? Most OEMs report
that the print speeds with white are the same as with CMYK.
However, when a high degree of opacity is required, or a printed
image is overprinted in opaque white, the printer may have to
make a second pass, affecting print speed.

Indeed, NUR's Dror Todress says that the addition of white
can affect speed, depending upon the print mode; “Using the
white ink as part of the image (spot white), there's no compromise
on speed. When covering areas with white (both pre- and
post-printing), there is a compromise on speed.”

“The only situation that slows print speeds is when working
with backlit applications as the printer 'double strikes' the image
area and lays down twice as much ink (all inks”?CMYKW) to
raise the opacity. However, this was the case before white, and
not a product of the new white inkset,” says Howard of Durst.

Ink/print costs: The jury is out on ink costs”?half the OEMs
queried for this article charge the same for their white ink as
they do for CMYK, while the other half charge more for white, citing
higher production costs.

What about possible third-party ink suppliers”?traditionally,
these companies have helped drive down ink prices. Most printer
OEMs don't see many third-party suppliers getting into the whiteink
game. For one, all current white inksets are UV-curable, which
are much more difficult and costly to produce. And, two, most UVcurable
inks (including white) are printer-specific”?making it less
likely that an ink producer can develop a single UV-curable white ink
that can be used on a variety of UV-curable printers.

“UV-cure ink is truly a systems approach that requires a finetuned
balance of the printhead, drive electronics, temperature control,
curing lamps, jetting, head-carriage speed, as well as the chemistry
in the ink,” says DuPont's Maribel Rivera. “White is no different.”

The new color of money

If you're considering adding a printer with white-ink capability, or
upgrading your current printer, the first question you need to ask is,
“Why do I need white?” Are there many jobs your company turns
away that demand white ink? Are there alternatives to needing
white-ink printers? What jobs could you bid on if you had white-ink
capabilities?

Backlits and printing on glass/clear substrates are the two most
popular reasons OEMs provide when asked about the need for
white-ink printers. Mimaki's Steve Urmano notes, “White-ink capability
is necessary when printing on clear substrates, but also when
printing on metal substrates. In addition, white is important for
overprints and underprints for special imaging effects.”

But print providers that take the leap to purchase a white-ink
wide-format printer need new customers to pay for this big-ticket
item”?prices start at $100,000 and top out at the $750,000 mark.
Many OEMs seem to favor the “Field of Dreams” philosophy”?”If you
build it, they will come.” But no one wants to bet their paycheck that
customers will indeed flock to their door just because they can now
print white in larger format. Of course, if a print provider already
owns a printer that now offers white-ink capability, the upgrade to
white is somewhat less painful to the pocketbook”?for example,
Durst charges $58,000 to $90,000 to upgrade existing Rho printers.

So, what new markets and applications exist for white? The
packaging and specialty applications are the future of white-ink
printing, says DuPont's Rivera. “The need to digitally print packaging
prototypes and very short runs is now emerging.” Other
applications for digital white include window graphics, backlits,
corrugated stand-ups, P-O-P, print-for-pay, and colored plastic
fluted sign applications.

Plus, as indicated earlier, printing with white ink allows shops to
offer comparable and competitive alternatives to more costly, and
complex screenprinting, says Howard. In addition, he believes that
the successful completion of one white-ink project will create
demand for more: “People see the impact white-ink printing can
have, and they want it for their image-based campaigns.”

In addition, Kerrie Mellott of Mutoh points out that Mutoh's
white-ink printers also have broken into a new market”?the printing
of circuit board, instrument panels, and semiconductors. Aellora,
in conjunction with its parent company Markem, is breaking
into the electronic, automotive, and medical component worlds; the
company also sees new opportunities in commercial signs,
awards, and promotional items.

A white future?
As with many other business decisions, whether you decide to
“go white” or not, will depend upon your particular operation”?
carefully weigh customer demand, potential new markets, and
competition, and evaluate the real need for new technology.
White-ink systems, says Nur's Todress, will help print
providers “develop new specialty applications, expand their market,
and secure higher margins.”
And, says Laura Wilson of Roland DGA, “In the long run,
white inks will save a tremendous amount of time and money,
particularly in labor costs. People will want to use white ink in
combination with all the other benefits that wide-format digital
printing offers.”
It certainly appears that many printer OEMs believe that
white ink for wide-format inkjets can become more than just a
niche market. Yes, printer manufacturers have an interest in
selling their wares and in “keeping up with the Joneses”?
Urmano of Mimaki says that white-ink printing “seems to be a
differentiator between many competing vendors”?but they
are aware that all the components that go into a white-ink
system have to work, or it will be all for naught. “When white
ink becomes practical to use and economically feasible, and
also becomes a standard feature for most or all inkjet printers,”
says Mutoh's Mellott, “white-ink printing will move from
niche to mainstream.”
”

Peggy Middendorf is managing editor of The Big Picture magazine.