With this system, a drop of adhesive is used to form a bridge between the component or wire, and the substrate. Exposure to UV light quickly cures it, and holds the component in place. Useful applications for NEA 123BL include, wire tacking, chip capacitor bonding, coil termination, and tamper proofing. The unique advantage of this adhesive is that even though it cures in seconds, it is extremely stable when not exposed to ultraviolet light. Norland 123BL is sensitive to the whole range of UV light from 320 to 380 nanometers with peak sensitivity around 365 nanometers.
Cure time is dependent on light intensity and thickness of adhesive layer.
The adhesives have been designed to be spot cured in small areas with hand held or desk top UV light sources that are safe and easy to use. These are most commonly used in conveyorized applications because the light must be shielded from the operator. In addition to the UV cure, Norland 123BL contains a latent heat catalyst that can quickly cure areas that do not see the ultraviolet light. Faster cure times are possible with infrared ovens. The advantage of the heat cure is to bring partially cured adhesive to full cure to get the maximum physical properties of the adhesive.