Many companies require every material in their products to be UL-approved.
What is usually meant by "UL-approved" is that the material must be flame retardant and thus fulfil the requirements of the UL 94 standard, which was drawn up by UL (Underwriter Laboratories) in the USA. Tribotec can currently offer three different circuit board coatings that are approved according to UL94 V-0: the two moisture-curing coatings ECC3010 and ECC3050S, and thermosetting ECC4865.
The UL94 V-0 standard means that the material will extinguish within 10 seconds if first fuelled with a 1000 degree flame. This means that in practice the material will not burn at all. Read more about the test criteria in UL94 here.
The table below is from the UL website, file E135148.
Both ECC3010 and ECC3050S are very fast curing
The advantage of a moisture-curing varnish is its ease of use: spray or pour the varnish over the components and leave it. The lacquer cures using the humidity of the air and needs no additional heat. A 100 micron (0.1 mm) coat of ECC3010 cures in just 10 minutes in normal humidity, and is dust-free after just 3 minutes. For ECC3050S the corresponding figures are 30 and 5 minutes respectively. If that's not fast enough, you can also heat to 60-70 degrees and get a through cure in 2 minutes. With such short curing times, there may not even be a need to consider UV-curing varnishes.
ECC4865 does not harden until you heat it
In some situations, you want a long open time at room temperature, for example if you need to dip coat and cover the entire circuit board. A moisture-curing lacquer is difficult to dipcoat with: it wants to cure with moisture and if you have the lacquer in a bucket where you dip, you immediately get a film of silicone rubber on the surface as soon as the lacquer in the bucket has contact with air. It is better to use a thermosetting varnish: ECC4865. It needs to be heated to over 105 degrees, preferably 120, but then it hardens within just a few minutes. Most electronic components can handle this without any problems.
All Tribotec circuit board coatings are solvent-free
Although our materials have a very low viscosity and short curing time, they are completely solvent-free. The coatings are developed in Japan by Momentive Performance Materials, formerly GE Toshiba Silicones. The coatings also have very low odour and are not classified as thermosets according to The Swedish Work Environment Authority regulation AFS 2005:18, the so-called thermoset plastics directive. They are also free of tin compounds. Therefore, no special extraction or other adaptations of the production premises are needed.
