DELO recently introduced a light- and humidity-curing sealant for connectors that are often found in vehicle control units or sensors. DELO DUALBOND GE4918 reportedly offers very good pin sealing properties, increases connector life, and allows efficient production.

Connectors need to be reliably sealed to protect electronics from humidity, media, and corrosion. Automotive suppliers generally use silver-coated connector pins since they are more cost efficient than gold and more reliable than copper. Silver is given an additional passivation layer to protect it from tarnish and abrasion. This coating is usually based on mercaptan and has been considered difficult to bond.

DELO DUALBOND GE4918 has been optimized for reliable sealing for these types of pins, according to DELO. It adheres well to the mercaptan coating and to typical connector housing materials (e.g., PA and PBT), even under the stringent conditions of the automotive sector. Since this new sealant is flexible in the cured state, it compensates for the different thermal expansions of metal pins and plastic housings. DELODUALBOND GE4918 offers very good temperature resistance (up to +150°C) and is able to keep connectors tight after thermal shock tests ranging in temperature from -40 to 150°C.

The new sealant reportedly enables fast and simple production processes with a high level of safety. The one-component product is easy to dispense, shows good flow properties, and can be fixed in 10-20 seconds with the help of high-intensity UV light. In shadowed areas that cannot be reached by light, a second curing mechanism allows the adhesive to fully cure under the influence of air humidity. An in-line tightness test can be performed immediately after UV light fixation.

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