What You Can Expect to See in the Ink Industry
Digital inkjet printing continues to rise in popularity, with no anticipated end in sight. This trend has led to advances in technology for solvent, UV and latex inks. So what can your company expect to see in the next five years?
Solvent inks are comprised of an oil based carrier fluid, resin and pigment. Solvents are divided into aggressive or “true” solvents, and eco-solvents. Aggressive solvents are a faster drying ink that does not work well on substrates that cannot tolerate heat. This form provides greater weatherability and scratch-resistance than eco-solvent. Solvents are best used for outdoor applications as they have a strong perceived odor, even after drying. A major concern of solvent inks are the harmful VOCs that are produced when printing. These VOCs require additional ventilation. In addition, solvent inks are often corrosive, and can cause damage to printheads.
Eco-solvents (or mild solvents) are similar to solvents. These inks are based in mineral oil, and have lower VOC emissions than aggressive solvents. In addition, eco-solvents give off a less obtrusive odor than true solvents, and may be used to print graphics for indoor applications (although there are some that argue that they still give off too much odor). These inks generally cause less damage than true solvents, but some printheads still have issues with eco-solvents as well. It is worth noting that eco-solvents are not environmentally friendly. It has been said that the “eco” is utilized for “economical”, although there is not a large difference in pricing between true and eco-solvents.
While other inks are gaining in popularity, it is doubtful that solvents and eco-solvents are going anywhere quickly because they are already so prevalent in the printing industry, with over half of all printers owning a solvent-based printing system. In addition, solvents produce bright colors and lightfastness which has yet to be replicated by UV inks. That is not to say that solvents are not without threats. Environmental regulations may certainly have an impact on the formulation of solvent inks due to their nature of emitting harmful VOCs into the environment. As the trend for environmentally products continues to permeate the industry, solvents may have to consider ways to be more environmentally-friendly. One of the biggest threats to solvents and eco-solvents may be latex inks as they increase in popularity.
Although already a solid technology, UV is expected to continue to grow in years to come. This technology has several advantages over traditional solvent ink in that it allows for greater versatility and faster turnaround speeds. UV also doesn’t emit the same harmful VOCs that are known to result from curing solvent inks. UV inks allow for a more productive end-to-end process and greater customer personalization. UV inks are also better suited for rigid substrates than other options. These types of inks also have low heat requirements (and low energy consumption), and often are able to produce specialty finish effects that are not obtainable with traditional thermal-cure inks such as solvents and water-based. One of the biggest benefits of UV is the ability to print directly onto the substrate.
What other trends can we expect in energy-curable inks? Printers can expect to see a rise in popularity for both LED and EB curing. LED curing is not reliant upon heat to cure, which makes it more suitable for a wider range of substrates which might be susceptible to damage caused by high temperatures associated with UV curing.
EB (Electron Beam) curing may also very well become more commonplace as it becomes less expensive to put in place. While this technology currently has a higher cost to implement, it may become more affordable in years to come given tighter environmental regulations and soaring energy costs. EB curing does not require inks to contain photoinitiators, which may be attractive for both ink manufacturers and printers, as manufacturers cannot always reliably source this component. Also EB has an advantage over traditional UV curing because it works not just on the surface, but deeper into the substrate itself for a full cure. This promotes better adhesion into a variety of substrates.
While at the moment, EB has not caught on as well as conventional UV or UV LED, it certainly could still be a key player in the future as smaller EB printers are being manufactured at more affordable prices. This technology could certainly take off if
acquiring photoinitiators continue to be an issue within the industry. Higher costs seem to be one of the most limiting factors for this technology.
LED is different than UV curable technology in that it produces energy from light-emitting diodes rather than UV lamp which produce a lower power output than traditional UV curing. This can provide printers with substantial cost savings. LED printing also increases the availability of substrates because they allow for printing on heat-sensitive substrates. LED technology also starts up immediately, unlike conventional UV which must heat up. This allows for increased productivity. These printers are also durable, with the LEDs themselves lasting up to 10,000 hours (or up to five years). Because they emit no heat, they also tend to experience less rising up of media, and therefore less damage from crashes. One of the most attractive features, especially in the culture of increasing environmental regulations is that LED doesn’t produce ozone gases. This eradicates the need for ventilation.
LED is expected to become more popular, but it will require that suppliers formulate inks and coatings that work well with LED technology. In the meantime, it is a good bet that should a company purchase a printer, he/she should go ahead and get dual technology of UV and LED.
Latex ink has been gaining ground in recent years. This ink works well for many of the same applications as solvent inks, but has several advantages. Latex inks do not require degassing, and the inks come out dry once they leave the printer. These prints have 3-5 years of outdoor durability without lamination. Latex inks also do not have the same odor that is notorious of solvent inks, which renders it useful for both indoor and outdoor applications. Many printers at this point still prefer solvents to latex because solvents can be used on a wider variety of substrates than latex. However, while latex isn’t brand new, it is still a developing technology, and the companies that produce substrates will likely create versions that are compatible with latex in the near future. In addition, latex is substantially more expensive than solvents, especially when one considers the lack of third-party options.
Latex is poised to take off in the future, especially with environmental regulations clamping down on issues such as VOCs. A key issue that is keeping latex from becoming a more popular option at the moment is that there are relatively few technologies available that support latex (outside of a couple major manufacturers), which has kept the prices high. Many printers prefer to pay less for solvents and tried-and-true technology. As latex becomes more reliable and understood, it will likely permeate the industry.