This enamel coats homemade circuit boards with the same type of green protective solder mask used on professional PCBs. We were discussing DIY solder mask in the forum, now Seeed has it for sale (or will soon). A three pack with red, blue, and green is only $6.50.
Seeed has a how-to tutorial. The paint is cured with a UV lamp or sunlight. Apply paint, cover with plastic and use a marker to black out areas that should be uncovered, expose for 10 minutes, wash with solvent.