New Dual-Curing Acrylic Adhesives With High Glass Transition Range
Panacol has expanded its portfolio of dual-curing acrylic adhesive systems with Vitralit® UD 8055 and Vitralit® UD 8056. The company reports that these adhesives cure primarily via UV crosslinking and have a secondary moisture post-cure for shadow areas. A special characteristic of these two adhesive systems is the high glass transition range of over 100°C, which ensures high-strength bonds even under temperature stress.
According to the company, the new adhesives are ideal for use as sensor encapsulation, encapsulation, component protection on PCBs, and in mixed bonding of plastics and metals where component undercuts or geometry-related cavities are present. This is precisely where they can show off their advantages: To ensure process-reliable curing even in shadow zones, both adhesive systems have been equipped with a secondary curing mechanism, downstream moisture post-curing.
In the first step, the bonded areas in the component are cured and fixed in seconds by UV radiation. Here, for example, LED UV curing units with a wavelength of 405 nm are used, which do not require any warm-up phases and thus enable the shortest cycle times. Here, UV expert Hönle offers a unique selection of spot and area lamps that are optimally matched to Panacol’s adhesives and can be individually adapted to the application requirements.
In the second step, uncured monomers are crosslinked in shadow areas by the humidity of the air without stress or thermal exposure. This technology enables fast cycle times and high volume production without subjecting temperature-sensitive electronics or components to thermal stress.
A high glass transition area (Tg) is particularly important when encapsulations, joints, structural bonding or, in general, bonded joints must withstand thermal stress over long periods of time…