Reconsidering Inkjet Inks Opportunities
Published: August 02, 2011 Category: Advanced Materials

Inkjet once seemed well positioned to gain revenues, market share and expanded addressable markets as the result of the demise of contact printers in the office.  Ultimately, however, it lost much of that market to low-cost laser printers.  As a result, the inkjet industry has been pushed into looking for new opportunities.  Its most noticeable success has been in providing color printers for the home and small business markets at prices that make these printers almost throwaway items.  Far less noticeable has been the rise of industrial inkjet, initially for graphics and, more recently for functional printing. With the home computing sector reaching some level of maturity, functional printing in particular (which remains at a very early stage of its evolution) looks like a potentially profitable future direction for the inkjet industry.
Functional jetting already seems to be a major preoccupation for some makers of inkjet equipment and print heads and service bureau.  However, the specific opportunities for ink makers and specialty chemical companies that are inherent in “jetted manufacturing” are not always all that apparent.   NanoMarkets believes that these opportunities are obscured by the extreme diversity of applications that fall under the title of “functional inkjet” and the resulting lack of color on just what kinds of inks are needed for these applications.  One of the main objectives of this NanoMarkets’ analysis in the functional inkjet ink space, therefore, is to sort through this diversity and to analyze where the revenues will be generated in the functional inkjet inks business over the next eight years.

Here we define “functional printing” to include any kind of additive process that is intended to create things rather than images.  As has often been noted, the biggest difference between functional printing and graphics printing is that while graphics printing is intended to produce something that is judged by its aesthetics, functional printing is supposed to produce something that works.  In the view of the firms we have talked with in the functional inkjet space, making something is harder than decorating it!

Be that as it may, we believe that the revenue-generating opportunities for ink firms in the functional inkjet space fall into five different classes of printing.

The “New” Printed Electronics and the Ink it Needs

For the most part, this is what most of functional jetting is about at the present time; using industrial inkjet printers to create small devices or small parts of larger devices.  Included in this class are applications as simple as printed silver interconnects between panels or devices, all the way through to completely printed computing chips.

This kind of functional inkjet can, in effect, be considered as an extension of a trend that has been around for decades in the form of thick-film printing of circuitry for membrane switches, automotive heaters and printed circuit boards (PCBs). It has also been the mainstay of photovoltaics; the silver grids that distribute the electricity from conventional (i.e., crystalline silicon) solar panels are printed using thick film techniques.  Broadly, these otherwise disparate applications share the fact that they are created using screen printing and that they involve a fairly low level of patterning compared to what is the norm in the semiconductor industry.

The undoubted success of the thick-film type of functional printing helped fuel the discussions and activities of a few years ago around of the concept of “printed electronics” (PE).  PE was a kind of functional printing that supposed to lead to printed devices that were much more complex/smaller than what thick-film technology was (and is) capable of.  The hope of PE in general was that using printing instead of the classical fabrication technologies of the semiconductor industry would reduce the costs of manufacturing a wide range of devices including displays, sensors, PV panels, batteries, RFID chips, etc.

The argument behind this hope was that (1) printing is additive, supposedly lowering the operational and materials costs of fabrication and (2) printing machinery is, generally speaking, lower cost than classical vapor deposition and related patterning equipment used in the semiconductor industry.  Although many kinds of printing were suggested or actually utilized as part of the PE paradigm, inkjet—because of its ability to finely pattern—has been frequently cited as the printing technology of choice for PE.

As it turned out, things did not go the way that PE’s advocates hoped.  There were many reasons for this.  There were certainly macroeconomic and other exogenous factors that have little direct relevance to the markets and ink-related matters.  For one thing the PE of a few years ago seemed to seriously overreach in terms of applications.  While the thick film revolution in its early days was firmly grounded in the huge consumer demand for new and better appliances and automobiles of the 1970s, PE seemed to be chasing of applications—such as flexible displays and RFID tags—for which there was little pent-up demand and whose timetable for adoption was very speculative.  The world’s financial pains of the last few years have not helped much either.

However, there were more fundamental reasons why the original PE did not take off.  Printing of functioning electronic devices turned out to be much harder to do than most of the people involved thought would be the case.  Firms leaped into the business of printing display backplanes or PV panels and found that their early timetables proved unrealistic. Some of the early firms went forward with their general business plans but quietly started to use more conventional deposition and patterning equipment with the promise that they would eventually use printing as they had already suggested.  Where inkjet printing was specifically cited as part of a manufacturing strategy this sometimes proved problematic because of scaling to higher speeds or the availability of inks.

Still “printed electronics” in the form described above seems to be seeing something of revival in the past two years or so, but the “new” PE is of a more pragmatic kind than the older type of PE that we described above.  The firms and individuals in this space now seem to have much more modest expectations.  Instead of being satisfied with nothing less than the printing of a complete RFID tag, they are now much more likely to be content with successfully (successful in both the economic and technical senses) printing just the antenna.  We note also that representatives of PE firms are now appearing at conferences that are primarily intended for the traditional thick-film industry, suggesting that the new PE thinking is that it might make money by improving on existing business models rather than by creating an entirely brave new world of printing electronics.

Inkjet’s role in all of this has yet to be determined.  From a positive perspective, we note that most of the firms that we spoke with in the inkjet industry seemed to think that the new PE would be the market sector that would generate the largest revenues for functional inkjet in the near term future. We also note that inkjet is very well established as an R&D tool in printed electronics, in part because, as a maskless technology, it is very well suited to making just a few devices.

Assuming that the new PE proves to have “legs” the primary opportunity that it seems it will create will be for conductive inks—especially silver inks—but semiconducting and dielectric inks are also an important part of this story going forward.  Printing silicon has been talked about and researched for a decade and appears to be on its way to attainment, but only slowly.

Inks and Jetted Bio-devices:  From Test Strips to Organ Printing

The use of functional inkjet for creating bio-devices seems to have emerged not so much from a jetting industry push, but more as the end-user community discovered that inkjet was capable of depositing small quantities of delicate materials.  Indeed, one major functional inkjet provider has reported that as the first overenthusiastic wave of the PE “revolution” retreated a few years ago, it derived some sales comfort from what seems to have been something of a surprise—biomedical markets.

This segment of the market is fairly diverse in terms of both applications and in terms of inks.  The applications that are usually cited as near-term ones are diabetic test strips and DNA arrays.  These are already very high volume products, with good prospects for the future based on current health and demographic trends. Inkjet is already used for both these products, although there seems to be some disagreement about the degree to which it is used to create diabetic test strips.

The use of inkjet is also expected to expand well beyond test strips and arrays.  Jetted biosensors have been created in the lab for quite some time, so it seems that this market could expand quite soon.  It is also very much in tune with larger trends in medicine, national security and environmental monitoring. However, there seems to be considerable enthusiasm for the use of inkjet in regenerative medicine; particularly in organ and skin printing.  While no one really expects this to be common in the near future, there seems to be a sense in the inkjet community that regenerative medicine will create significant revenues for inkjet.

This raises the question of what materials can be made profitably into jetted bio-inks.  The answer seems to be that most can be.  At various time times inks have been made out of a wide range or organic molecules (including DNA), proteins, cells, etc., although primarily in a research context.  We also note that this application sector can overlap in terms of inks with the PE sector.  For example, silver inks may well be used in sensors of various kinds.  It also seems likely to us that for the regenerative medicine applications that some see as being jetted in the future a whole range of new inks will have to be developed.

Inks for printing on Non-Standard Substrates:  Tiles, Textiles and Beyond

Printing on non-standard substrates does not quite seem to fit the usual definitions of functional printing. This is because nothing is specified about function as such, leaving open the possibility that inkjet will be used to decorate rather than to add/increase functionality.

And this is precisely the case.  One opportunity that is mentioned frequently in this category is that of ceramic inks, that is inks that can coat ceramic substrates (primarily tiles) with color.  This is not an easy thing to do because ceramics are so porous, so special inks are needed.  The other non-standard substrate that receives significant attention in the inkjet community is fabric/textile.

In both cases, the motivation for printing onto these substrates is to create small runs of decorated substrates to respond to the consumer need for a wide range of colors and styles in tiles, fabrics and clothing and also to ensure that a specific color and pattern not be too widely distributed.  Everyone wants to be reasonably certain that his or her kitchen will look significantly different from that of friends and relatives!  The main reason why inkjet is seen as having an opportunity here lies in inkjet’s ability to create products in small numbers, because it is maskless.

A variety of specialized inks have been developed for these applications.  Pigments used for printing onto ceramic tiles are usually large particle size, stable inorganic powders that must be able to withstand a high-temperature firing step (up to 1300°C) required to fuse the powder into the molten surface of the ceramic tile. There are even specialized inkjet printers for ceramic printing, although these seem to use sol-gel inks rather than inorganic pigmented inks.  Meanwhile, some observers believe that inkjet technology has the potential to replace existing finishing and coating technologies and create new materials for the technical textiles sector.  Another use for functional inkjet in the textile sector is as tool for smart textiles to put into place the materials that enable the textile to respond to mechanical, thermal, chemical, electrical or magnetic stimuli.

Inks for 3D Printing:  New Life for Manufacturing

“3D printing” refers to creating a one-off (or limited volume) product, by building up the product one layer at a time.  This technique has been available for some time and has mostly been used for prototyping in a wide variety of industries.  However, the technique is now being expanded to the manufacture of products that are actually sold on the market.

This trend has led to 3D printing being heralded as a new form of manufacturing that might reindustrialize the developed world, create manufacturing industries in the less developed world and create an entirely new form of manufacturing environment in which a far greater variety of products than now can be highly customized, either at the factory itself, or by the end user.

Because 3D printing can be used for so many applications, the materials used for this kind of functional printing are very diverse.  In addition, we note that not all 3D printers are inkjet printers in a conventional sense.  There are specialist 3D printers which are inkjet-like in that they have nozzles but for large scale modeling these may enable large amounts of material to be deposited; quite the opposite to standard inkjet.

On the other hand, most 3D printing is done with more standard industrial inkjet machines and alternative approaches are available.  In one method—sometimes called the MIT method—the layers are built up starting with powders, but these powders are formed into a solid layer using liquid binders which are deposited with inkjet.  An additional resin may also be used to give the finished product more durability.  This approach is fast and relatively low cost, but tends to produce rough looking objects and, given the number of materials, is fairly expensive.

Another approach, which is superior in a number of ways, is polyjet printing.  In this process, as the name suggests, the printers have two or more jetting heads.  Typically, one builds the model, while the other jets the support fluids.  The support material is a gel-like substance, which is easily washed away.  The final model is said to have a smooth finish and be ready for sanding, painting, drilling, or tapping.

Inkjet and Fluid Micro-dispensing:  Not Quite Printing

In essence, functional inkjet machines are devices that can accurately deliver small quantities of fluid without much wastage.   This fact can be exploited by using inkjet as a dispensing tool and a market for doing just that has emerged.  Typically, the use of functional inkjet for micro-dispensing applications is not just to place small amounts of material, but also where they must be dispensed in the form of fine structures such as micro-lines, micro-dots, and three-dimensional structures.  Although micro-dispensing isn’t quite printing, this patterning aspect makes the line between microdispensing and printing quite small.

Using inkjet for micro-dispensing has a number of advantages and, of course, which of these advantages matters depends on the particular application.  However, in general, where inkjet shines in this regard is that it is a non-contact printing method (and hence can dispense onto delicate substrates) and it has the ability to cover large areas. Additionally, it is an on-demand process and conducive for printing multi-layer devices.

The fluids for which functional inkjet has been used to date include a variety of biological materials along with some non-biological materials such as solders and adhesives.  Within the biological sphere, inkjet is considered to be a good microdispensing technology for reagents, enzymes and other fluids that are deposited on biological substrates.  Microdispensing using inkjet has been demonstrated with a wide range of viscosity and rheological properties.

Functional Fluid Making Opportunities for Inkjet

The five areas outlined above will present considerable opportunities for materials firms and ink makers to produce fluids suitable for jetting.  None of the five areas are new.  Nonetheless, NanoMarkets believes that functional jetting is about see a resurgence for a number of reasons.

One of the most important of these reasons is that industrial inkjet machines have now reached a speed where they can be deployed for serious manufacturing applications, although it is important to note that we are talking about the larger and more expensive machines here.  Conversely, smaller and lower-cost machines, priced at well under $10,000 may open up the market to an entirely new kind of manufacturing—desktop manufacturing—that could parallel the success of the desktop publishing revolution of a couple of decades ago.

We also note that this isn’t the only important trend with which the process of functional inkjet may be aligned.  For example, within the scope of functional jetting comes a broad range of biomedical applications, all of which make small contributions to the urgent need to improve healthcare.  Also, some marketing experts see the need for industry and commerce to offer more customized products in the sophisticated markets of the developed world.  Here again, functional inkjet can be of help.

We believe that there is plenty of room for ink and materials firms to tap into these opportunities.  Eventually, these firms will start to offer off-the-shelf inks for functional inkjet, although this opportunity still seems to be one that will not produce significant revenue for quite some time to come; it will have to await the standardization of applications, which seems a long way off.  For the time being, we think that most opportunities for materials are going to require some customizing for specific applications or even specific customers.  Nonetheless, we have little doubt that these are real opportunities.