We have gadget we're selling, and we'd like to obscure the part numbers of three small, thin ICs. Currently we're globing the tops with Thermalloy green thermally-conductive epoxy, mainly because we have it and it looks cool, shiny green, when it's cured. But it's messy to mix and takes a day to cure, or an hour or so in an oven.
Any better ideas? Something fast and that looks good. Maybe even different colors for different chips. Needs to be permanent.
Grinding the markings off is messy and ugly.