When Buckingham-based vehicle monitoring technology provider Traffic Technology was looking to integrate new bonding methods into its manufacturing processes, it called on the tesacohesion team for help.

Traffic Technology Ltd is a leading UK supplier of advanced vehicle monitoring technologies, road safety equipment and services. The company designs, supplies, installs and commissions innovative solutions for monitoring vehicles, cycles and pedestrians, as well as unique road safety devices.

During the design phase of an interactive cycle awareness sign, the options explored in conventional bonding were found to be ineffective. As a result, Traffic Technology decided to search for a high performance double-sided tape solution that could effectively fasten and provide a long lasting, durable seal on the dissimilar substrates of the sign's polycarbonate screen and powder coated aluminium frame.

To ensure they delivered benefits in line with the 4 P's - people, products, processes, performance - that make up the tesacohesion philosophy, tesa's customer team visited Traffic Technology and engaged with them in a thorough assessment of their requirements.

Any proposed solution needed to provide a high strength bond on the dissimilar substrates in an outdoor environment.  A watertight seal was also required to enable an IP65 rating on the unit. As such, whilst a double-sided closed cell foam tape was originally requested by the customer, the tesa team recommended testing the tesa ACXplus 706x series of acrylic double-sided tapes, as a more suitable alternative.

tesa ACXplus double-sided tapes for constructive bonding offer a very high bond which can last for decades on materials with different surface characteristics.  Excellent stress dissipation properties allow substrates with different rates of thermal expansion and contraction to be reliably joined.  The temperature, weather and chemical resistance make these tapes suitable for long-term outdoor applications, where materials can be bonded without damaging or changing them.

As well as optimising the wetting of different surfaces, the specially balanced viscous and elastic performance absorbs dynamic forces and vibrations to relieve stresses, leading to the creation of dimensionally stable and permanent bonds.

Materials with low surface energy, such as the powder coated materials in use by Traffic Technology, are often described as hard-to-bond. The black, viscoelastic foamed acrylic core of tesa ACXplus 7065 provides a high immediate tack and peel adhesion for securely bonding combinations of low surface energy materials.

During the testing programme, tesa provided consultation on the processes required to ensure correct application of the tape and samples of tesa ACXplus 7065 - a 1.2mm tape from the tesa ACXplus 706x series. 

The results were immediate.  Once constructed, the customer was able to move the constructed test unit straight away, mounting it on an exterior wall to monitor performance in a typical environment. 

They were also able to see how using tesa ACXplus 706x would benefit their manufacturing activities in scaled up production, through its rapid and straightforward means of application.

After a two-month period the unit was removed and positively signed off on all the customer's required criterion. Proving it can compensate for the different thermal elongation and contraction factors presented by the dissimilar materials, the watertight seal created by the tape showed no evidence of water ingress in the enclosure, allowing the safe housing of the sign's electronic components. 

Roger Westwood, Operations Director at Traffic Technology said:  "As we're increasingly using a combination of different materials in the design of our products, it's imperative to find a solution that is capable of optimising these materials to best effect, whilst enhancing our manufacturing methods.

Double-sided adhesive tapes offer us greater design freedom to produce more advanced and innovative developments for a wide range of traffic monitoring and road safety applications."

As a new design and concept now in production, initial demand for the interactive cycle sign, manufactured with tesa ACXplus 7065, is forecast at 50 production units per year in the UK and there are also plans to roll this out across Europe.

As a result of its successful co-operation with tesa, Traffic Technology is also looking at other areas where tesa ACXplus can be integrated into existing product designs moving forward.