SPECIALTY CHEMICALS

FIT TO PRINT
Inks and pigments business is growing through digital printing and from a desire for UV-curing and special effects in packaging applications

ANN M. THAYER, C&EN HOUSTON

	HOT OFF THE PRESS Use of wide-format ink-jet printers is gaining in the printing of large signs, posters, and banners. FLINT INK PHOTO

Although Johannes Gutenberg is known for creating movable metal type in 1456, his contribution to ink is less often acknowledged. Inks combine a colorant, namely a pigment or dye; a carrying vehicle, usually petroleum or vegetable oils, solvents, or water; resin binders; and additives such as wetting agents, waxes, and driers. When Gutenberg found that waterbased inks were too fluid to print cleanly, his use of linseed oil as the vehicle set the course of printing.

More than five centuries later, water-based inks or those containing other environmentally friendly solvents have regained favor. Environmental concerns, largely around volatile organic compounds (VOCs) and heavy metals in pigments, have compelled new chemistries and changes in formulations. Now, new technologies in both ink production and printing processes are presenting further challenges and added market opportunities.

Pigments make up about 10% by weight of printing ink shipments, but they account for a more significant share of the cost. In 2001, the nearly $5 billion worth of printing inks sold in the U.S. used about $800 million worth of pigments, according to the market research firm Freedonia Group. The European printing ink market accounted for another $2.7 billion.

Most major producers make pigments not only for printing--the largest end-use market, consuming about 30% of production--but also for paints, coatings, and plastics. Carbon black accounts for about 70% of printing pigment volume, while the more expensive organics, including azos and phthalocyanines, dominate in value. Specialty pigments, representing a small but fast-growing market, are used in part for creating specific effects.

SPECIALTY CHEMICALS

INK AND PIGMENT producers say printing ink markets grow at roughly the same rate as gross domestic product and thus have slowed with recent economic declines. Still, a shift toward more expensive digital and energy-cured inks is fostering growth for these products. Inks for digital printing, such as ink-jet products, are expected to grow nearly 11% or more annually; however, they account for only about 5% of total demand.

"There is some optimism that a slow recovery will begin in the second half" of 2002, says Joseph B. Raksis, senior vice president for research and new market development at Flint Ink. Reduced readership and less advertising, along with competition from electronic media, are some factors negatively affecting the printing of newspapers, magazines, catalogs, and direct mail.

Flint Ink, with annual sales of more than $1.4 billion, is a privately owned producer of inks and--through its CDR Pigments & Dispersions business--of pigments. Together, Flint and Sun Chemical--which has about $3 billion in sales--along with INX International, are the world's leading ink producers. Sun is a subsidiary of Japan's Dainippon Ink & Chemical.

Like Flint, Sun's colors group also makes pigments and is a leading pigment producer, along with firms such as Clariant, Ciba Specialty Chemicals, BASF, and Engelhard. Most pigment manufacturers produce a range of organic pigments and dyes, while a few also make some inorganic pigments as well as finished inks.

The price-to-performance ratio is a critical aspect of the highly competitive printing ink and pigment markets, producers say. "Users are always trying to drive price down, and certainly the biggest element of that ink cost is the pigment," says Roland Valin, technical sales and marketing manager for the colors side of Engelhard's appearance and performance technologies division. Competition has also increased from pigment makers in China and India.

Consolidation has been prevalent on both the ink and pigment levels of the business. In the U.S. alone, more than 200 ink producers range in size from local mom-and-pop firms to large international operations. Many, especially Flint and Sun, have been built up through mergers and acquisitions of smaller operations over decades, if not centuries.

Two of the most recent deals were Sun's purchase of Bayer's organic pigments business in the U.S. and Flint's merger with ink producer Gebrüder Schmidt in Europe. In January, Heubach GmbH, a producer of organic and inorganic pigments, acquired Bayer's lightfast pigments line.

	DAZZLING Clariant produces a broad range of azo, phthalocyanine, and polycyclic organic pigments. CLARIANT PHOTO

ACQUISITIONS HAVE been a key strategy to expand the colors business at Sensient Technologies, formerly Universal Foods. After selling its foods businesses, the firm used the money to buy SynTec in Germany and, just recently, ECS Specialty Inks & Dyes in Switzerland. The company's specialty inks and dyes business, which includes products for ink-jet and laser printing, has gone from nothing four years ago to about $125 million in sales projected for this year.

Producers anticipate that consolidation will continue. While cost saving is a factor, critical mass may be more important. "On the ink side, it's important to have a reasonable regional, if not global, presence," says Alexander Sieber, head of the ink pigments unit in Clariant's pigments and additives division, especially as printing and packaging customers themselves globalize and look for global suppliers.

Publishing accounts for only 23% of ink demand, whereas the largest end-use markets are packaging, at 36%, and commercial printing, at 33%, Freedonia reports. Gravure inks and lithographic inks, the latter for the most widely used process in publishing and commercial printing, are losing ground to flexographic inks, particularly in printing packaging materials.

"Packaging applications remain solid, as people continue to buy food and other consumables and want more functional and attractive packaging," Raksis explains. This market is also demanding higher quality color, which employs more of the higher priced organic pigments.

From a technology perspective, solventless energy-cured inks are becoming popular because they have faster setting times, higher gloss, low VOCs, and improved chemical and rub resistance. This ink technology also works on almost any substrate--especially nonporous ones such as plastic, glass, and metal that can't absorb traditional ink vehicles--by polymerizing the ink with ultraviolet or electron-beam radiation.

"Once you have applied the radiation, the ink is completely cured and the printed material can be handled immediately," Clariant's Sieber says. Easier handling, reduced downtime, and less waste and cleanup make these inks cost-effective.

"A pigment supplier is always being challenged to provide pigments that result in inks with good flow properties, high gloss, excellent color stability, fast transfer, rapid drying, and acceptable economics," says Peter A. Lewis, director of communications and regulatory affairs at Sun Chemical.

And new packaging materials or substrates always present new challenges, he adds. "If a suitable solvent/resin system is found, then we as pigment manufacturers have to be able to supply a pigment that will wet out and disperse in such a system."

Packaging customers also are calling for increased visual impact. "Everybody is looking for customization and product differentiation," says Stephane Rochard, global marketing manager for automotive and industrial markets in Engelhard's appearance and performance technologies division. Metallic, fluorescent, pearlescent, photochromic, or thermochromic pigments can create the desired special effects. New products include ones that give a "liquid metal" or anodized look.

Engelhard's special effects pigments, Rochard explains, are based on three principal chemistries: mica, bismuth oxychloride crystals, and borosilicate flakes. Beyond packaging, they are also used for wall coverings, specialty papers, and some commercial printing. And demand is growing for effects pigments in security applications and anticounterfeiting measures.

ALTHOUGH END-USE application and substrate are major factors in ink formulation, the printing process is as well. "New technical developments in printing processes seriously affect printing inks for both print media and packaging," says a spokesman for BASF Drucksysteme GmbH. The BASF printing systems business produces printing inks and plates, while other BASF units produce pigments and dyes.

BASF and other ink and pigment producers anticipate, for example, a gradual shift from sheet-fed to digital printing methods, such as ink-jet printing, in a variety of end-use markets, even textiles.

There are two ink-jet processes: continuous, where ink under pressure forms a stream of droplets that are then directed into place, and drop-on-demand, in which the ink is released as needed. Drop-on-demand technologies can regulate ink pressure through electrical and mechanical means, such as piezoelectric print heads, or by temperature, where heat generates vapor bubbles to force ink droplets through the nozzles.

"The entire prepress area has been digitized and computerized for just about all printing processes," Flint's Raksis explains. Digital printing then allows printers to customize each print--for example, in color or with unique information--at relatively low cost and rapid turnaround for small jobs. Other printing technologies have substantial start-up costs--making plates or cylinders for each image--and the overall economics depends on spreading that cost over thousands of copies.

"In general, digital printing has not penetrated industrial printing markets since it is relatively slow and expensive, but improved technology is on the way, and this segment will grow substantially in the next five to 10 years," Raksis says. An exception is in the printing of large-area signs, posters, and banners, where digital printing is already replacing traditional methods.

"Ink-jet printing historically has been geared primarily toward the desktop printer," agrees Mark Carrier, vice president for Avecia's ink-jet printing materials business. Personal or office printing is a relatively small-volume business, but "over the years, the technology's improved considerably in speed, image quality, and cost, such that now it is migrating off the desktop into the realms of the large traditional printing industry."

Avecia created its business in 1985, when ink-jet printing was in its infancy. Along with Avecia, other ink producers, including Sun and Flint, have created divisions devoted to the rapidly growing digital printing market.

"Sun has been rapidly expanding its technology to service this market over the past five to six years," Lewis says. "Such inks have to print at the speeds and temperatures required by these processes, besides being both color stable and resistant to flocculation. The dispersion of pigment into the ink vehicles has to be absolutely ideal; otherwise, blocking of the print head will occur."

INK-JET PRINTING started with dyes, which differ from pigments in that they are dissolved, rather than dispersed, in the carrying vehicle. "The reason is obvious--you have to push the liquid through very fine nozzles--but dyes have certain advantages and disadvantages compared with pigments," Clariant's Sieber explains. "One major disadvantage is the stability, particularly light and weather fastness, so for long-lasting prints, particularly for outdoor applications, you'd better use pigments."

Improved dispersions are making pigment use possible in ink-jet applications, Sieber and others point out, through more finely ground pigment particles and narrow particle-size distributions. Additives that stabilize the dispersions are an additional approach to reconfiguring inks, including energy-cured inks, to suit ink-jet printers. Yet another is making functionalized pigments, with added chemical groups to make them more soluble or reliable in ink-jet inks.

"The challenge is getting the ink to work with the print heads--it's a hand-in-glove relationship--and then that ink has also got to work on the substrate," Avecia's Carrier says. "So it's getting a balance between ink, print head, and substrate."

A major goal in ink-jet printing is to achieve photoquality prints, and it's created a new demand for higher performance inks and pigments, producers say.

"While printing speed is the most important parameter for industrial applications, image quality is the primary concern in the photographic area," says Christine Halik, head of marketing for photographic, reproduction, and digital printing in Ciba's coating effects segment. Ciba is focusing on tailor-made pigments for ink-jet applications, dyes with improved resistance properties, and polymers for photoglossy ink-jet media or substrates.

Image quality is highly dependent not only on the inks but also on the paper or substrate. A plus for pigment and ink producers is that ink-jet photo prints use relatively large quantities of materials.

"Once ink-jet printing has the durability and the costs closer to what you would pay for silver halide snapshots, it should be able to penetrate a big portion of the photographic market," Carrier says. "It's still very early in the growth curve of digital photography taking off with ink-jet printing, but when it does, it should be a very big business.

"A main thrust of Avecia's business is developing dyes, with a target of 'silver halide-parity,'" he adds.

Equipment manufacturers have begun building photocapabilities into most printers, offering systems for the professional photo market, and developing self-service or retail kiosk and minilab capabilities. The idea is to go from computer to print, simplifying the process and increasing flexibility and customization.

For example, Hewlett-Packard and Kodak created a joint venture two years ago called Phogenix Imaging that launched its first product, the DFX digital photofinishing system for retailers, in February. The $39,900 minilab uses HP's thermal ink-jet technology and Kodak paper and software for image editing, enhancement, and sizing, and to control the work flow.

Potential one-hour services include custom print packages, special-sized prints up to 12 inches by 18 inches, posters, calendars, greeting cards, and CD-ROMs. Phogenix says the DFX system produces "high-quality, low-cost prints that meet or exceed today's retail photofinishing standards."

Partnerships, such as that between Kodak and HP, are common and extend throughout the pigment, ink, printing equipment, printing, and end-user business chain. In addition, many ink and pigment producers bring together internal organic and inorganic color expertise and formulation experience, as well as dispersant, additive, and polymer capabilities from across their companies.

The pigment and ink development process is extremely R&D intensive, producers say. "In all printing applications, it is very important to work closely with the customer, since their needs are often very specialized and we want to make sure our products meet their expectations," Raksis says.

TEXTILES

Ink-jet Printing Moves Into Fabrics

	FLEXIBILITY Fabric patterns can be changed quickly and cleanly using ink-jet printing. CIBA PHOTO

Ink-jet technology is finding use in textile printing, where it offers flexibility, customization, short runs, and affordability, for example, when sampling patterns. Ink and pigment producers are responding with products that work both in the print heads and on different fiber substrates.

"Customers are interested in printing in one step, using inks that combine a pigment and binder, so that no fabric preparation is needed," explains Mickael Mheidle, head of new business applications for Ciba Specialty Chemicals' textile effects segment. For this market, the company produces water-based inks that are entirely picked up by the fabrics, leaving no waste products and requiring no cleanup between runs.

Ciba also is developing a range of inks to work with a new textile printer being developed with Reggiani Macchine Spa and ink-jet technology firm Aprion Digital. The system, which they hope will print between 150 and 200 m² per hour at 600 dots per inch, is being tested by key customers.

Last year, DuPont launched an integrated system that combines its Artistri Ink, which uses traditional textile colorants, and Artistri color control and management software, for color matching and reproduction, with an ink-jet printer made by VUTEk. DuPont says the system, which can print 30–60 m² per hour at 720 dpi for wide-width (3 meters) home furnishing applications, reduces cycle times from the many weeks needed with traditional textile printing to a few days.

Top