UV Curing Adhesive for Glass Bonding

How a whiskey bottle manufacturer achieved a clean, automated fix for custom metal decals

In premium spirits packaging, presentation is everything. For one whiskey bottle manufacturer, the challenge of bonding decorative metal decals cleanly and reliably to glass – as part of a high-speed automated production line – called for a precise UV curing solution that could deliver consistent results without compromising the aesthetics of the finished product.

This use case explores how a carefully specified UV curing adhesive system, combined with the right lamp technology and full UV safety support, met every requirement of a technically demanding application.

The application and background

The client operates in the premium spirits sector, producing whiskey bottles destined for retail and export markets where brand presentation and finish quality are critical differentiators. As part of a packaging enhancement programme, the manufacturer wanted to apply custom-designed metal decals to the exterior of glass bottles – a process that needed to be integrated seamlessly into an existing automated production line.

UV curing adhesive technology was identified early in the process as the most promising route, offering the combination of on-demand cure initiation, clean finish and production speed that the application demanded. With experience supporting bonding and curing applications across manufacturing, electronics, aerospace and automotive sectors, we were well placed to help the client navigate the options.

The challenge

The manufacturer had a clearly defined set of requirements that any solution would need to meet in full. The adhesive bond had to be strong, durable and critically, completely residue-free. Any visible glue or adhesive bleed around the edges of the metal decals would be unacceptable on a premium product, ruling out many conventional bonding methods.

The process also needed to operate on demand, with cure initiated at a precise point in the automated cycle rather than relying on ambient conditions or time-based curing. The existing line used an index curing configuration, advancing bottles through the curing station in groups. The system needed to cure up to four bottles simultaneously, with a curing area of 40 x 40mm per bottle and a target cure time of no more than 6-8 seconds per cycle.

Space within the existing line was limited, and temperature sensitivity was a further constraint – the solution had to perform reliably without generating excessive heat that could affect the product, the adhesive or surrounding components.

The solution

Following a detailed review of the client’s process parameters, we identified a UV curable adhesive specifically formulated for glass-to-metal bonding applications. The adhesive was designed to cure under 395 nm UV light – a wavelength in the long UVA range that offers effective cure initiation while minimising heat generation, making it well suited to temperature-sensitive applications.

With the adhesive chemistry confirmed, attention turned to the UV lamp system. The criteria were exacting: the lamp needed to deliver sufficient irradiance at 395 nm to cure the adhesive across the full 40 x 40mm bonding area within the 6-8 second process window, across all four bottle positions simultaneously.

We evaluated lamp options against the specific irradiance output, beam uniformity and working distance required by the process. A high-intensity UV LED lamp system was selected, offering precise wavelength output centred on 395 nm, consistent irradiance across the curing area, instant on/off operation suited to index curing cycles, and a compact housing that could be accommodated within the available space on the existing line.

The system was configured and tested against the client’s process parameters before installation, confirming that cure times, coverage and output consistency all met the required specification. Integration into the existing automated line was straightforward, with the lamp system designed to interface cleanly with the line’s control architecture.

The outcome

The installed UV curing system delivered on all three of the client’s core requirements. The metal decals were bonded cleanly and securely to the glass bottles with no adhesive residue or bleed, meeting the aesthetic standard demanded for a premium product. The 6-8 second cure time was achieved consistently across all four bottle positions, maintaining the throughput of the existing production line without modification to the index cycle. The compact lamp system integrated into the available space without issue, and the temperature-controlled output of the UV LED technology ensured that heat generation remained within acceptable limits throughout production.

The client reported a reliable, repeatable process from the point of commissioning, with no significant modifications required following initial installation.

UV safety and compliance

Wherever UV light sources are introduced into a working environment, safety and compliance must be addressed alongside the technical solution. UV LED systems operating at 395 nm present a lower acute hazard than shorter-wavelength UV sources, but prolonged or repeated unprotected exposure still carries risk to eyes and skin — and employers have a clear legal duty to manage that risk.

Under the Control of Artificial Optical Radiation at Work Regulations 2010, which bring EU Directive 2006/25/EC into UK law, the manufacturer was required to assess the risk to workers from the new UV light source and implement appropriate controls. We supported the client fully in meeting these obligations.

This began with guidance on equipment selection that took UV safety into account alongside process performance – ensuring the lamp system specified was appropriate not just technically, but from a hazard management perspective.

We also delivered UV risk management training for the client’s safety team, equipping them with the knowledge to manage UV hazards on an ongoing basis, and provided tailored UV hazard awareness training for production workers – covering the specific lamp, wavelength and working environment they encounter daily. This worker-level training is not optional; it is a mandatory requirement of the Regulations, and ensuring it reflects the actual equipment and process in use is essential for both compliance and genuine worker protection.

If you are working with UV curable adhesives, exploring bonding solutions for glass, metal or other substrates, or integrating UV curing into an automated production process, we would be glad to help you work through the options.

With over 20 years of experience across manufacturing, packaging, electronics and beyond, we can support you from initial specification through to safe, compliant implementation – including all necessary UV safety assessment and training for your team.