The UV industry is changing. Raw materials have been reclassified under REACH regulations. As a result, ink formulations must adapt as UV-LED curing continues to gain momentum across more printing and industrial applications.
Change is always a challenge, but what is less helpful is the amount of misinformation that can accompany it. This is particularly true regarding mercury arc-lamp systems and regulatory reviews of products containing mercury.
In recent months, Holly Steedman has often been asked, “Are UV mercury arc lamps being banned?” She has also heard statements such as, “Mercury lamps will no longer be available” and, “Every printer needs to move to LED in 2027.” These statements have circulated within the industry for some time. Understandably, they have caused concern among equipment manufacturers, printers and end users. The actual position is considerably more nuanced.
LED is undoubtedly an important part of the future of UV curing and, for many applications, it already offers considerable technical and commercial advantages. However, that does not mean mercury UV technology has suddenly become obsolete. Neither does it mean that regulation requires every existing process to convert to LED. Understanding the difference is important if businesses are to make sensible investment decisions.
Much of the uncertainty around mercury in UV curing comes back to the EU Restriction of Hazardous Substances Directive (RoHS). Directive 2011/65/EU restricts ten substances – including mercury – in electrical and electronic equipment. However, certain equipment is outside its scope. Included are large-scale stationary industrial tools and large-scale fixed installations. This importantly covers most UV-curing industrial installations.
“24 February 2027 is not an automatic cut-off date for mercury UV-curing equipment”
The key information is in Annex III 4(f), which addresses lamps containing mercury. For the UV industry in printing and coating, the key exemption is 4(f)-IV, covering “mercury in lamps emitting light in the ultraviolet spectrum”.
Its current published expiry date is 24 February 2027.
It is that date which has generated much of the concern. In addition, it has unfortunately, led to some misleading claims that mercury UV-curing lamps will become unavailable in Europe from February 2027. Nevertheless, this is not the current regulatory position.
“LED curing has developed rapidly and offers some compelling benefits”
A renewal application was submitted for exemption 4(f)-IV and 4(a)-I (other low pressure discharge lamps). The stakeholder consultation closed in August 2026 and 94 responses were published. IST INTECH was among the organisations supporting renewal. The company presented evidence for the continued need for mercury UV technology in specific industrial applications. Oeko-Institut undertakes this process. The institute is an independent European research and consultancy organisation focused on sustainable development and environmental protection.
The consultation has therefore finished, but the review has not. The process has now moved into its assessment and decision-making stages. Oeko-Institut will assess the submissions and prepare its recommendations for the European Commission. Following on from this, the Commission will consider the evidence and determine the future of the exemption.
Under the RoHS renewal process, a timely renewal application means the existing exemption remains valid until the Commission makes its decision. Mercury UV lamps covered by 4(f)-IV and 4(a)-I can therefore continue to be placed on the EU market while the application is being evaluated. Equipment containing those lamps can also continue to be used and supported.
While the renewal remains under consideration, 24 February 2027 is not an automatic cut-off date for mercury UV-curing equipment or replacement lamps.
The outcome has not already been decided. The European Commission could renew the exemption, amend it or ultimately decide not to renew it. At this time, it has
not taken such a decision. This is expected later in 2027, but no fixed date has been issued yet.
These are the remaining steps in the process:
Assessment by Oeko-Institut as of September 2026:
• Review of stakeholder submissions
• Additional stakeholder exchanges or technical discussions, if required
• Preparation of final consultant assessment report and submission to the European Commission
European Commission evaluation:
• Consideration of the consultant’s recommendations and supporting evidence and drafting of delegated directive
• RoHS Expert Group comitology process
• Discussion and consultation with member state experts
Adoption of delegated directive by European Commission:
• Formal adoption of the Commission’s decision regarding the exemption renewal
• Two-month scrutiny period by the European Parliament and Council for possible objections
This is where separating fact from speculation matters most. There is a significant difference between the following statements. Mercury is increasingly regulated and industry should prepare for continuing change (which could be possible in the future). As opposed to, mercury UV curing lamps have already been banned. They
have not.
The previous review outcomes in 2015/16 and 2020/21 excluded large-scale stationary industrial tools and large-scale fixed installations. However, LED curing does have some limitations for some applications. The current exemption review took this into account. When considering stakeholder comments, the consensus is that this review will reach the same conclusion. This is why it is important to take part in the review process.
Therefore, for manufacturers and users, the logical response is not to ignore the regulatory direction. Neither is it to make an immediate technology change simply because of a date in a headline. Existing mercury UV operations can continue during the review. Meanwhile, businesses should monitor the outcome and consider what LED could offer and, if suitable – when planning new equipment – process changes for future investment.
This gives a much better starting point for the technology discussion which is not simply mercury versus LED. Each technology needs to make technical and commercial sense today. It is also important to look at how that may change in the future.
Another source of confusion is the Minamata Convention on Mercury.
The Minamata Convention is an international treaty designed to protect human health and the environment from mercury. It covers mercury throughout its lifecycle, including mining, trade, products, emissions and waste.
It has resulted in the phase-out of several mercury-added products. More recent amendments include phasing out remaining categories of fluorescent lamps for general lighting purposes by 2027.
The words “mercury lamp” and “2027” appearing together make an effective headline. However, they do not mean that every mercury-containing lamp used for every industrial purpose is being prohibited. The distinction between general lighting and specialist industrial UV applications is important.
This is exactly why it is important for companies to look at the wording and scope of the legislation. As opposed to making investment decisions based on a headline, social-media post or sales claim.
None of this changes the fact that the move towards LED is real. LED curing has developed rapidly and offers some compelling benefits. Systems can provide instant on/off operation, long operating life and reduced energy consumption. Because the LED source contains no mercury, it also removes mercury from that part of the process.
For heat-sensitive substrates, compact equipment, digital printing and applications requiring frequent switching, LED can be particularly beneficial.
The ink and chemistry landscape is changing alongside the hardware. Regulatory pressure on certain substances and photo-initiators is pushing the change of formulations. As a result, requests for LED-curable versions of products are increasing. At the same time, original equipment manufacturers (OEMs) and end users are increasingly focused on energy consumption and the wider environmental impact of production.
Consequently, in many new machine developments, it makes complete sense to investigate LED from the outset. But “investigate LED” does not always mean “LED is the right solution”.
One fundamental technical difference is spectral output. UV-LED lamps typically produce UV within relatively narrow wavelength bands. In the UVA area, common wavelengths are 365nm, 385nm, 395nm and 405nm. A medium-pressure mercury lamp produces a much broader spectral output across UVC, UVB and UVA.
A key difference in spectral output is that UVC wavelengths are typically not integrated into UV-LED systems for print and coating applications. UVC LEDs are commercially available, typically at wavelengths of around 265–280nm and their performance continues to improve. However, current UVC LEDs generally offer significantly lower efficiency and optical output than established UVA LED technology. Additionally, their higher cost makes them commercially unviable.
UVC wavelengths typically improve the surface cure of the chemistry on the substrate. This can be an advantage in applications that require high levels of scratch resistance, such as floor coatings.
In other words, some formulations and industrial processes still benefit from, or require, that broad spectral output. IST INTECH’s long history in UV development shows that a mercury lamp may be required when a formulation’s spectral requirements fall outside the available LED curing wavelengths. That is why replacing an arc lamp with an LED unit is not necessarily a straightforward hardware substitution.
The ink or coating may need reformulation. Process speed may change. Adhesion, through-cure, surface cure and final material properties all need to be considered. The economics of changing a mature, validated industrial process can also differ greatly from specifying LED for a new machine.
For some applications, LED will deliver a better process. For others, mercury arc remains technically appropriate today.
The conversation around curing technology is also happening against a wider shift in UV ink and coating regulation. Photo-initiators and other raw materials continue to face regulatory scrutiny. This means formulators are already reviewing existing chemistry and developing alternatives. This creates an interesting opportunity.
Where an ink has to be reformulated anyway, it makes sense to ask whether the new formulation can also be optimised for LED. In some markets this can accelerate the transition because chemistry and curing technology can be developed together, rather than treating the lamp as an isolated component.
Mercury is a hazardous substance and environmental and safety requirements mean its use, handling and disposal must be controlled. Spent lamps need to be managed and recycled correctly. In addition, the industry’s responsibility to reduce environmental impact should not be forgotten. A UV lamp/bulb supplier can advise on returns. Spent lamps should be returned to a supplier or licensed recycler and customers can request evidence of recovery rates. Most suppliers have a return scheme in which a high percentage of the mercury is recycled and reused.
At the same time, regulation needs to be accurately discussed. The global mercury issue is much wider than industrial UV curing. The United Nations Environmental Programme (UNEP) data cited in the supporting research identifies artisanal and small-scale gold mining and coal combustion among the major global sources of mercury emissions.
Creating fear around an imminent ‘mercury ban’ may encourage equipment investment. But it does not necessarily help customers to make the right technical decision.
Looking at which curing technology is right for a process and how the regulation change might affect that decision over the lifetime of equipment is a more appropriate consideration.
The direction of travel towards LED is clear and its role in UV curing will continue to grow. Improvements in output, wavelength options, chemistry and system design mean applications that were difficult to address with LED several years ago are increasingly achievable today.
But industrial technology rarely changes overnight. Existing processes, validated formulations, equipment lifetimes and applications requiring particular spectral characteristics all have to be considered.
As part of the Metz group, IST INTECH and its sister company IST METZ, offer both technologies for precisely this reason. IST INTECH specialises in LED curing for inkjet applications. The company’s objective is to understand the application and specify the curing solution that delivers the required result.
For a new application, that may very well be LED. For an established process, it may be LED following appropriate testing and reformulation. In other cases, an arc system may remain the technically and commercially sensible choice.
The regulatory landscape will continue to develop and the current RoHS review is an important one for the printing industry. It is important to follow it closely. Steedman would recommend consulting with recognised associations such as Radtech Europe to stay up to date with the latest status. Radtech Europe is the European association for energy curing technology.
Good investment decisions need good information. In the current debate around mercury and LED, separating fact from noise is probably the most useful place to start.
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