Grafica News - February 2018
"Screen Printing Process is Changing, but not becoming Obsolete. WHY?"
Does the new, hyper-connected business world mean the 'end' of screen printing? No, it doesn't. Many applications exist, particularly in manufacturing, that are crying out for the quality and characteristics that screen printing – and in some cases, screen printing alone – provides. So, Screen printing continues to gain momentum in manufacturing and industry.
As a manufacturer of screen printing inks, it is important for us to clearly communicate – and exploit – the advantages of industrial screen printing. After all, it has truly unique attributes. For example, screen printing is currently the only process that can vary the ink coating to create layers of varying thicknesses. Additionally, screen printing inks boast high resistance to chemicals and mechanical strain. This enables them to be employed on challenging substrates such as glass or injection-moulded components. Moreover, this technology ensures high colour intensity, excellent flow properties, and high process flexibility – all in combination with low capital expenditure. The new hyper-connected age of manufacturing is not closing the door on screen printing. On the contrary, it is opening up entirely new ones.
Building on the strengths of screen printing
Our new glass ink demonstrates how it is possible to build on the strengths of screen printing. This new ink was designed to handle challenging substrates and high thermal loads; it can be employed in applications that entail extremely high temperatures – temperatures that are simply too high for conventional organic inks. This special single-component ink for glass can withstand high temperatures during production processes, for example during the manufacture of OGS (One Glass Solution) touch screens; it can also withstand extreme thermal loads during actual use of the final products, such as laboratory glassware and light bulbs.
In-mould decoration (IMD):
Not only does screen printing provide a beautiful look and feel – its unique properties make it ideally suited to in-mould decoration (IMD). This is especially important in the context of the stringent quality and safety requirements of the automotive industry. It is also relevant for the manufacture of buttons, switches, and consoles for medical devices and household electronics. For IMD processes, screen-printed polycarbonate film is placed in the mould prior to injecting the plastic. This results in pristine printed decorations securely bonded to the substrate. It is critical to ensure that there is no washout effect during injection. Screen printing inks for in-mould decoration boast high adhesion to polycarbonate film, highly flexible ink film for exceptional mouldability, and strong bonds to injection mouldings.
Smartphones and touch screens:
Smartphones and touch screens have created a market for screen printing that did not exist 10 years ago. And this market has enormous potential; 1.5 billion smartphones were sold worldwide in 2013 alone. The 3C (computing, communication and consumer electronics) market is booming, and has extremely high standards in terms of materials. This applies especially to inks, which must provide exceptional resilience and coverage. Touch screens for smartphones pose a particular challenge – two layers of ink must be printed on top of each other, and must together not exceed a thickness of just 30 μ. This is equivalent to roughly half the thickness of a human hair. Digital printing does not provide the precision necessary to align these two layers perfectly. Screen printing is the only process that provides the correct properties and sleek visual appearance when printing on glass.
Screen printing offers many advantages, such as the resilient ink, colour brilliance, variable ink film thickness, and the ability to precisely align ink film edges. It is also the best choice for graphic applications requiring special effects, exceptionally brilliant colours, or adhesion to transparent substrates. Overall, combining screen printing with other processes will become increasingly common. Ink manufacturers like us must make customers and potential partners aware of the advantages of screen printing. They must show not only what it can already do, but what it could do in the future.
Screen printing needs to remain an attractive process, regain lost traction, and – most importantly – become dominant and irreplaceable in new markets. Innovation is critical to achieving these goals.
Screen printing: Graphics applications:
The demand from the graphical market will continue to fall. Historically, screen printing was the only choice for many applications. But it is being increasingly supplanted by other methods – first and foremost, by digital printing. Digital methods deliver full-colour results quickly and flexibly – without the time and expense of making and changing plates.
These strengths are highly attractive, especially as the world of manufacturing becomes increasingly connected, and increasingly geared to mass customization. Processes and value chains are becoming ever-more dynamic, integrated, and flexible. This is enabling the manufacture of customized products at the same low cost as standard mass-produced items. In other words, product personalization is advancing hand in hand with greater productivity. Companies that fail to recognize these trends – that fail to embrace lower costs, longer product life cycles, and new technologies – will be left by the wayside.
With the market for graphical screen printing rapidly shrinking, the future of the process itself seems to be in peril. Not a day goes by without further bad news. There is no denying the fact that screen printing is no longer the all-conquering force it once was in the graphical space.
By Thorsten Kraus,
Area Sales Manager, Screen and Pad Printing Inks
Marabu GmbH & Co. KG