| abstract |
This invention relates to a solder mask composition for thermoplastic substrates. The solder mask has critical components which include a polyhydroxyether and melamine formaldehyde. Other components include a solvent, filler and flow control agent. Optional ingredients include a colorant, epoxy resin and acid to promote the reaction of the composition. A surfactant can also be included. The solder mask provides the necessary flexibility and adhesion required for thermoplastic circuit boards. The mask can be applied directly to a circuit board or to a transfer medium for subsequent covering of a substrate. It relates to an article which can be a circuit board. It also relates to a process for making such composites which includes processing the solder mask. |