Panacol, Hönle, and bdtronic recently partnered to ensure precise adhesive dosing, capillary flow, and curing in seconds with ultraviolet (UV) light. A main field of application for adhesives in medical systems is needle bonding and syringe assembly in high-volume production.
As the needles are produced in large quantities, rapid and reliable bonding is essential. In addition to their mechanical bond strength, the adhesives used must allow high-precision production and permanent joining and must withstand various sterilization methods. Panacol's UV-curable Vitralit® adhesives meet these requirements. Vitralit adhesives are reportedly available in various viscosity ranges to fit the design of the needle hub and fill the gap between the hub and the needle. The material of the hub and needle also affects the choice of the adhesive: Many adhesives are UV curing, which requires the use of transparent and UV-permeable materials. For materials that block UV light, such as polycarbonates, long-wave LED-curable adhesives are recommended.
All Vitralit adhesives recommended for needle bonding are solvent free and certified USP Class VI and/or ISO 10993 for use in medical equipment. In addition, high needle extraction forces were measured with all needle bonding adhesives, even after several sterilization cycles. For visual quality inspection, fluorescent versions of medical-grade adhesives are also available.
The choice of the adhesives requires a matching dispensing system for reliable and precise dispensing in a rapid production environment. With the mini-dis solution provided by bdtronic, dispensing in microliter range is made easy, regardless of the adhesive viscosity. Thanks to the continuous volumetric dispensing, the dispensing is pulsation free, ensuring optimal process speed, repeatability, and accuracy.
Finally, the choice of the UV-curing equipment depends on the adhesive and the wavelength that triggers polymerization. For needle bonding with Vitralit products, it is possible to use either UV-A or visible LED light. Due to a special LED assembly and an optimized electric power supply, Hönle LED Powerline LC guarantees a high-intensive irradiation for fastest curing and shortest cycle times. In addition, the irradiation time can be selected in a range of 0.01-99.99 sec and thus precisely adapted to the process requirements.
Hönle LED Powerline heads have a compact design for an easy integration into any production line. The high-intensive, water-cooled LED-UV is suitable for clean room operation.