Solving LED Challenges with Silicone Sealants
A silicon sealant coupled with automated dispensing is helping one LED manufacturer enhance product performance and reliability.
Based in the UK’s West Midlands, Mackwell Electronics provides technology solutions for the global lighting industry. The company’s background in electronics has enabled it to develop a wealth of experience in lighting solutions for customers worldwide. Operating from a purpose-designed R&D and manufacturing facility, Mackwell’s philosophy of never leaving safety to chance has led to the design of a portfolio of high-quality, durable emergency LED lighting products for a wide range of applications, including entrance lobbies, hospitals, hotels, elevators, offices, and staircases.
Mackwell was recently trying to reliably bond a clear plastic lens into a self-contained emergency light housing that had to be sealed to IP65 standards for challenging environments. Techsil was invited in to discuss various clear bonding options, including cyanoacrylates, UV-curing adhesives, and silicones.
The lighting units were being produced in volume batches on the shop floor. Since hand bonding was not viewed as efficient, a semi-automatic bond application was envisaged. To tackle the challenge, Techsil took away a housing and lens for assessment and trials back at its testing facility in Bidford on Avon, Warwickshire.
After a number of in-house trials, Techsil prescribed and sampled Momentive’s Snapsil TN3005-C, a clear, 1-part, low-volatile siloxane, thixotropic silicone sealant with a fast tack-free time. TN3005 C offers primerless adhesion to most substrates and cures at room temperature to a 22 Shore A rubber. Bonded units were sent away for rigorous testing and passed with flying colors.
Techsil liaised with Mackwell’s engineering department regarding a dispensing system; the Nordson Performus™ III was recommended. The compact, operator-controlled benchtop system is used with an electric foot pedal. This provided the advantage that it could be used with a preparatory feed valve that Mackwell already had on site to power the dispenser.
The Performus dispenser can handle all assembly fluids. With fast, controlled application, it can make dots, beads, and fills. Mackwell now has this system in operation and will adapt it further to complete a variety of other in-house bonding applications. This dispensing system has increased throughput, improved yields, and reduced production costs overall.
Snapsil TN3005-C silicone adhesive sealant has proven to be a high-performance material that has stood up to rigorous testing and will last for the life of the product. Being a 1-part material, no mixing and no primer are needed, making it easy to use. Techsil used its understanding of adhesives and application knowledge in real production environments to find a cost-effective, reliable solution for Mackwell that has enhanced product performance and profitability.