From the Foundry to the Pressroom: Vertical Integration of Metallic Pigments.

Since the early eighties, a number of the manufacturers of metallic pigments have entered the printing ink business as specialist manufacturers of metallic inks, selling their products wholesale to other, conventional ink producers.

This process of vertical integration has both challenges and benefits. The essential challenge of any vertical integration is to unify successfully the efforts of different types of businesses. Before considering the benefits of such a union it is interesting to have a brief look at the differences between the two activities.

Metallic pigment manufacture is essentially a metalworking process. A blend of the appropriate metals are melted into an alloy in a foundry. The molten metal is cast into a coarse, sand-like powder, and this material is then milled (forged) into the desired size and shape for pigments.

The manufacturing procedure is primarily a physical process, not a chemical one. The end products of the same alloy are virtually chemically identical to one another.

For example, a rich gold flexo pigment is chemically the same as a rich gold pigment for litho inks. The differentiation of the various finished products is largely a matter of physical parameters such as size and shape. This is a simplistic description of metallic pigment production because the chemistry of the metal can't be ignored.

During the manufacturing procedure the surface of the metal is coated and various steps are taken to control the degree of oxidation that occurs. In the case of aluminum pigments, extraordinary care must be taken during manufacture to prevent the very reactive metal from potentially explosive oxidation.

Also, the simple statement that grades of metallic pigments are determined largely by parameters of size says nothing about the major engineering feat that is required to accomplish the necessary degree of classification.

In fact, there is nothing simple about any part of the manufacturing process, but it is a process of physical, rather than chemical, manipulation.

The technology of printing inks is vastly different. The production of most of the resins and pigments used in inks are procedures of chemical synthesis where organic precursors are chemically combined to produce entirely new materials.

Even though the final stage of ink making is a physical blending of relatively inert materials (UV and EB inks excepted), the ink formulator is primarily concerned with the chemical interaction of the various ingredients and their interaction with the chemistry of plates and/or press chemicals and the substrate. Further, the chemistry of printing inks is under the broad category of organic chemistry, a very different branch of knowledge than metallurgy.

Except in the particular case of metallic inks, there is practically no commonality between the two disciplines.

A combination of metallic pigment production with ink making may seem to be a mixed marriage because of the vast "cultural" differences between the methods of the two types of businesses.

It is a long way from the foundry to the pressroom. In spite of this, the integrated manufacturers have expanded their efforts and investments.

This integration into the ink industry also seems unusual considering that printing ink is only one of several industries that use metallic pigments and not necessarily the largest end user. What makes these "marriages" work? And, what advantages does a metallic ink specialist bring to an ink maker?

The old saying that "opposites attract" comes close to describing the logic of integration in the metallic ink business. In this case, a more accurate phrase would be "opposites synergize." Printing ink manufacturers have very specific requirements for the pigments that they can best use. These requirements are not necessarily obvious to the engineers and technicians whose training, responsibilities and career experience are related to metallurgy. The synergism that is created by integration manifests itself in several broad categories.

Customization of Pigments

Metallic pigments are hundreds of times larger than most of the organic pigments that are regularly used for printing inks. Another fundamental difference is that the pigment size and particle size distribution has very much to do with its appearance, color and performance in a particular application.

Metallic ink specialists have developed an in-depth knowledge of specific effects in inks that are related to size, shape and distribution properties. By having pigment technicians and paste and fluid ink formulators under the "same roof" there is rapid, two-way communication between the various technologies. All parties become more aware of the requirements of each. The insights and experiences of both the ink and pigment teams are combined.

This interface between departments has lead to the production of pigments that are closely tailored to a particular end use.

For example, this type of interaction at MD-Both has led to the development of several new "cuts" of pigments for flexo and gravure applications.

These highly differentiated classifications have a major impact on applications. The coarser material yields unparalleled metallic brilliance for large print forms. Smaller tightly classified particle pigments provide a vast improvement in performance in applications using fine anilox rollers and/or intricate patterns or fine text.

Different applications have different requirements for optimum performance and appearance.

These new highly classified products have a much larger percentage of pigment in the ideal size range by removing the undesirable coarse "tails," which can cause poor printing, and also by removing much of the dust-like "fines" which detract from metallic brilliance.

The narrow particle size distributions also contribute to more predictable rheology of the inks. The evolution of these products required a close cooperation between the ink and pigment teams since the degree of classification necessary was not precisely known at the outset and their development entailed the introduction of new manufacturing and quality control methods.

This customization process is not only related to the appearance of the pigments. One of the limiting factors in metallic ink formulation is the relative reactivity of the metal to other components of the ink.

Traditionally, some of the most desirable resins and solvents for making ink were not suited for metallic formulations because of the possibility of causing pigment tarnishing or gassing in the case of aluminum pigments.

Gassing is the build-up of hydrogen in the ink container caused by reaction of the aluminum to acidity in the vehicle. New techniques of metallic pigment polishing and coating have vastly increased the ink formulator's palette of suitable raw materials making possible both better performance and longer shelf life.

Shortened Product Development Cycles

This issue is closely related to the first. Metallic pigment plants are expensive, elaborate and highly customized. Consequently, they are difficult and time-consuming to modify and any decision to do so will be made very cautiously.

Close cooperation between the ink and pigment departments assures that the right product will be produced and modifications to the plant can be made more quickly and more confidently.

The benefits to the metallic pigment/ink producer and their customers, of rapidly bringing innovations to the marketplace are obvious. Lowering the risk and speeding up the return of introducing new products creates a favorable environment for research and development, which is the seed corn of any technology-based business.

The introduction of new metallic pigments used to be rather rare. Often, years used to elapse between launches of truly new products. This is certainly not the case today. Metallic ink and pigments are evolving as rapidly as the rest of the ink industry. Over the last two years, MD-Both has introduced new flexo and gravure pigments and inks, new offset inks for modern presses, new offset inks for coating and laminating and new UV/EB offset and flexo inks.

Concentration of Resources

Concentration of resources is perhaps the largest single reason for the emergence and growth of integrated metallic ink/pigment specialists. There are several characteristic difficulties associated with metallic ink manufacture.

Due to the peculiar nature of metallic pigments the methods, materials and equipment used for metallic inks are very specialized. High shear mixing and milling machinery that is universally used in conventional printing ink manufacture is unsuitable for metallic inks. This type of equipment is designed to reduce the particle size of the pigments in the ink, which in the case of conventional inks is desirable. In the case of metallic inks, the properties of the inks are designed around and derived from the particle size.

Although it is possible to produce metallic ink on conventional equipment, there is a very high risk of harming the pigments with a consequent loss of properties.

In the interests of quality and consistency, it is far better to produce metallic inks on specially designed equipment.

Further, an ink maker electing to make their own metallic ink will need to maintain inventories of expensive raw materials and finished products that, in spite of recent improvements, have shorter shelf life than conventional inks.

Yet another consideration is the fact that the demand for metallic inks is notoriously mercurial with large seasonal and annual fluctuations. Is it economical for a conventional ink manufacturer to incur the costs of a dedicated metallic ink plant and carry out research and development projects for metallic inks and commit the necessary personnel to carry it out, all for a segment of their business that is probably less than 1percent of the total?

The personnel issue is a critical one. Most ink lab managers will say that they are understaffed. The ever increasing trend of placing in-plant personnel at printers is causing a chronic shortage of qualified ink technicians almost everywhere. How much time does a manager want his staff to devote to metallic inks?

Yet, because of the very nature of metallic inks, they tend to be used on high value, high quality jobs where any lack of performance and quality will be extra noticeable.

Besides providing the products, metallic ink specialists also have experienced technical staff that are intimately familiar with metallic inks and are a source of expertise for their customers. A major part of the value that metallic specialists deliver to their customers is the focus of a vast amount of resource on a small portion of their business and the elimination of the above mentioned considerations by out-sourcing to specialists.

Globalization and Consolidation

The same forces that are driving the consolidation in the printing ink industry in general are also affecting the metallic pigment/ink manufacturers. The challenges of the metallic ink business aren't lessened just because one specializes in it.

All of the issues of costs, customized equipment, inventories, etc., do not go away for those that are in this business. But, by concentrating on metallics and growing the business, they do become more manageable.

Extending the reach of the business across national and regional boundaries does much to smooth out the fluctuations in demand. Consequently, the metallic pigment/ink business became globalized sooner than much of the ink industry.

This trend also contributes to the acceleration of product development since innovations in printing and/or ink technology anywhere in the world are quickly communicated to everywhere else.

The specialist nature of all the facets of the metallic pigment/ink business with its consequently capital intensive manufacturing plant has necessitated the mother-plant approach for the producers.

While the large conventional printing ink companies may have many manufacturing sites, metallic producers have just a few with national or regional sized capacity Although this is simply a manifestation of the economics of the situation, it dovetails nicely with the requirements of the conventional ink makers.

Recent consolidation in the printing industry means that the same printing job may be running simultaneously at various places around the country or the world. With centralized production, metallic ink producers can guarantee their customers that many different branches receive metallic ink that has been manufactured under identical conditions, some times even that all receive the same batch of ink.

To conclude, clearly, it is a long way from the foundry to the pressroom. But, as explained above, the advantages derived from the integration make the effort and investment worthwhile.

Because of it, today's ink makers have a wider variety of better metallic pigment and ink products available to them than ever before.

Jay Brooks is technical manager of MD-Both Industries. He has been in the printing ink field for 17 years, concentrating on pigment dispersions and specialty inks.