High Performance Pigments

By David Savastano, Ink World Editor | 09.12.05

Despite higher costs, improved properties are driving growth for high performance pigments in a variety of printing markets, including packaging, outdoor signage and non-impact printing.

For the most part, the pigment industry has been faced with ever-tighter margins and greater competition in recent years. One of the few bright financial spots has been high performance pigments (HPPs), a more expensive group of pigments that provide better resistance properties.

HPPs are a major part of the overall pigment business. David Dugan, sales/key accounts manager at Clariant Corporation, estimated the market for high performance pigments to be approximately 19,000 tons, or approximately 9 percent of the total organic pigment market. The value of these pigments is estimated to be $1.2 billion, compared to $4.2 billion for the entire pigment market.

Pigments courtesy of Sun Chemical Corporation, Performance Pigments Group.
HPPs are also a growing business.

“Whereas the total organic pigment market the growth rate is more or less mature, increasing at moderate 2 percent per annum, the growth rate for high performance pigments is commonly believed to be in the range of 4 percent to 5 percent,” Mr. Dugan said.

“The market for HPPs has been strong,” said Edwin Faulkner, director – communications and regulatory affairs for Sun Chemical Corporation’s Performance Pigment Group. “Low interest rates over the last several years have resulted in good performance for the
automobile and housing industries, the combination of which consumes the majority of the HPP production.”

What are HPPs?
As noted above, HPPs impart specialized characteristics to the end product.

“A high performance pigment shows high performance properties in its end use application,” Mr. Dugan said. “This definition refers to inorganic as well as organic pigments. As far as the performance is concerned, one should note the Three Essential E’s defined by Gunter Buxbaum (“High Performance Pigments,” Ed. Hugh M. Smith), which are effectiveness (technical performance); economy (benefits to the customer); and ecology (environmental and toxicological safety).”

Mr. Faulkner also defined HPPs. “The three essential elements of an HPP are excellence in performance, persistence in application and high value-added economics for all parties in the supply chain,” he said. “HPPs are those pigments that exhibit very good to excellent properties of persistence. That is, they have resistance to light, heat, humidity, organic solvents, water and detergents.”

“A high-performance pigment is characterized by a high level of permanence in the end application, acceptable in product safety and environmental issues and good value-in-use to the user, despite a relatively high price per unit weight,” said Christopher Bridge, regional marketing manager – Americas, imaging and inks business line, coating effects segment at Ciba Specialty Chemicals.

Mr. Bridge said that among the properties HPPs typically provide are high lightfastness and weather-fastness, fastness to chemical exposure in the end application, high stability to heat, low solubility in application systems and low migration.

“HPPs show high color strength, high insolubility and heat stability,” Mr. Dugan said. “Furthermore, they have extremely good light- and weather-fastness properties, solvent and bleeding fastness and low migration. Because of these properties, they are preferentially used in all applications which require excellent light and weather fastness, such as all outdoor applications like automotive coatings, exterior house paints and outdoor signs.

“Other performance characteristics notable of certain HPPs include fluorescence, luminescence, thermochromatic, photochromatic and other ‘effect’ pigments,” Mr. Dugan added. “Functional colorants, such as pigments with controlled triboelectric properties, are required in electrophotographic toners.”

HPPs encompass a wide variety of pigments, including specialty phthalocyanine (blue and green), indanthrone, quinacridone, perylene, DPP, specialty napthol, carbazole violet, benzimidazolone, azo condensations, metal complex pigments and isoindolinone.

“High performance pigments can be defined by what they are not,” said Chris Whiston, product manager, pigments for Toyo Color America, LLC. “They are not azo pigments. With a few notable exceptions, they are polycyclic pigments, the most common and famous of which are phthalocyanine pigments. The notable exceptions classified by Herbst and Hunger, (Industrial Organic Pigments, 1993) as azo pigments are azo methines, azo metal complexes, azo condensation and benzimidazolone pigments. Compared with azo pigments, high performance pigments generally provide improved lightfastness, heat fastness, weatherability, solvent and migration resistance.”

“Most high performance pigments are polycylic organic pigments, but the term can also cover certain inorganic pigments with low environmental impact, such as bismuth vanadate types,” Mr. Bridge said. “The organic pigment types include the main classes of isoindolinone, azo condensation, quinacridone, dioxazine, dipyrrolopyrrole, perylene and some higher grade pigments of the naphthol and benzimidazole.”

“Benzimidazolone-based pigments mark the entry point for high performance pigments,” Mr. Dugan said. “Disazo benzimidazolone pigments such as Pigment Yellow 180 and Pigment Orange 72 (PV Fast Orange H4GL) have been particularly developed for plastics. Pigment Yellow 180 is the colorant of choice for toners in digital printing, as well as certain specialty packaging inks.

“Another striking example for a HPP is Pigment Violet 23, also known as carbazole violet, which is, next to phthalocyanine blue or green pigments, perhaps one of the single most important high performance pigments used for almost all applications all over the world,” Mr. Dugan said. “Pigment Violet 23 is reddish-violet in color and is characterized by an exceptionally high tinting strength, a matchless vividness of shade, very good light fastness and very good heat stability in almost all plastics.”

“In the orange and red shade area the quinacridones, perylenes, perinones and diketo pyrrolo pyrroles are the well-known and favorite high performance pigments with excellent light and weather fastness, high heat stability and satisfactory migration properties,” Mr. Dugan said. “An outstanding class of high performance pigments are the phthalocyanine blue and green pigments, with overall excellent fastness properties as well as heat and migration stability.”

Major Customers for HPPs
Because of the improved properties HPPs offer, the cost for high performance pigments is higher than conventional pigments. For the most part, the classical lower-cost azo pigments meet the needs of printing inks, so the use of HPP is rather limited. As a result, HPPs are used in applications where cost is less of a concern, such as in automotives, plastics and ink jet printing.

Although the coatings industry is the main consumer of of HPPs, with approximately 50 percent used in the automotive sector, demand for HPPs continues to grow in the printing industry.

“Major customers for HPP pigments are the automotive coatings industries, the plastics industries, the non-impact-printing industry and also companies producing packaging inks with high quality demands,” Mr. Dugan said.

“The excellent performance properties of the HPPs are accompanied by higher costs of manufacture which results in higher selling prices in the marketplace,” Mr. Faulkner said. “As a result, the HPPs are generally used in applications where their properties are valued and necessary.”

For printing, the need for improved performance properties often necessitates the use of HPPs.

“All ink makers have some end use application where the relatively high unit price can be recovered through the value to the end user,” Mr. Bridge said. “This means any application where one or more of the key property enhancements is necessary. The main areas of use are applications for outdoor use (signs, decals for transportation, fertilizer bags, filling station forecourt items) or indoor applications where some extra degree of light permanence is necessary, such as wall and floor coverings.”

“Like the other end use applications for HPPs, the printing ink industry uses them where their properties are necessary,” Mr. Faulkner said. “The most common uses are Red 122 (used in place of R57 where light stability is an issue); Blue 16 and Blue 79 (used in place of B15 where reduced levels of copper are important); various HPP yellows (used in solvent inks where chemical resistance is needed); various HPP reds and yellows (used in laminating inks, particularly flooring); and various HPP reds and yellows (used in specialty metal deco, screen and outdoor poster applications where light and humidity resistance are important.)”

“Printing ink applications include, but are not limited to, specialty packaging such as retort packaging, outdoor printing such as signage and package printing for products normally stored outdoors,” Mr. Dugan said. “Other HPP applications include security inks, metal decorating inks and electrophotographic toners. One additional important use is in color filters for liquid crystal displays.”

Mr. Bridge said that high performance pigments are more likely to be used in applications where the substrate is not paper.

“All printing processes use high performance pigments to some extent, though the participation of offset is much lower than for overall printing – the usual substrate, paper, is often limiting the end application,” Mr. Bridge said.

“Screen inks are used for signage and decals, and are being replaced by wide format solvent-based ink jet, which also uses these pigments,” Mr. Bridge added. “Flexo printing is used for fertilizer bags. Gravure printing is common for wall and floor coverings. Offset printing is used for special high-end applications which may require chemical resistance or lack of migration, mainly in labels, or where the substrate is not paper, such as certain credit cards or metal decoration.”

New HPP Products
In response to increasing demand for new products, pigment manufacturers are developing new HPPs for the markets they serve.

Clariant has introduced HPP Hostaperm H5G and Hostaperm Blue R5R for automotive coatings and Novoperm THI Red 4G70 for industrial paints, and Mr. Dugan said that these may also find their way into some specialty ink applications.

“An example of a quite recent development by Clariant is the class of thiazine (THI) pigments, which shows analogy in molecular structure to diketopyrrolo pryrrol pigments, another example of high performance pigments with excellent properties,” Mr. Dugan said.
Clariant has also introduced Novoperm THI Red 4G70, a red pigment which exhibits a clean opaque scarlet shade and has excellent heat and chemical resistance and good lightfastness, as well as Ink Jet Yellow 4G and Ink Jet Magenta E02 for pigmented ink jet inks. For toner applications, Clariant has recently introduced Toner Yellow 3G and Toner Magenta E02.

Ciba’s introductions include two new chemistry types. Ciba Chromophtal Yellow LA has extremely high lightfastness. Its major use is for decorative laminate flooring, particularly where it is exposed to daylight for long periods. Ciba Chromophtal Yellow 2RT is a red shade yellow isoindoline pigment, which gives excellent strength, gloss and rheology performance for high fastness solvent-based inks.

Mr. Bridge also said that Ciba has launched an improved strength and dispersibility dimethyl quinacridone pigments, Ciba Chromophtal Pink PT (SA).

Sun Chemical has introduced three R122 products that exhibit excellent dispersion, flow and lightfastness properties: 228-6488 / 228-6832 for metal deco and solvent packaging inks and 228-8655 for aqueous packaging inks. Sun Chemical also added 279-5700 for laminating inks to its Y139 line.

Mr. Whiston said that Toyo has introduced new indanthrone products (Lionogen Blue 6500 and Lionogen Blue 6510) that are surface-treated PB 60s that provide outstanding coloristics; a phthalocyanine (Lionol Green 6Y-600), which offers a very yellow shade saturated PG36 and a new quinacridone (Catulia Magenta D) which is a dispersible, clean, bright yellowish PR122. Toyo also has introduced two dioxazine products: VC 6100 for offset inks and VC 6195 for packaging inks, as well as Toyo PV23, its original technology. Mr. Whiston added that production of PV23 has been successfully transferred from Fuji, Japan to Monterrey, Mexico to manage cost while maintaining product performance and environmental integrity.

More so than the organic pigment market, the high performance pigment segment has been flourishing, with healthier prices translating into both a better return on investment and more research and development. As a result, new products are emerging which should help ink manufacturers formulate specialized products, which should benefit their customers in the printing industry.

Mr. Bridge sees a bright future ahead for these pigments.

“The market for these types of pigment grows steadily, as applications become more demanding in both performance and environmental impact and users look for solutions which have a wider area of application,” Mr. Bridge said.

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