Additive for laser welding Polycarbonate

We are currently working on a project to find if it is possible employ laser welding to bond our polycarbonate parts. The point is, that we need to weld two pieces of clear, colorless polycarbonate, so using carbon black on one of the welding partners is not possible. We are thinking of an additive or masterbatch we can mix in with one of the welding partners during processing. This additive should absorb energy in the IR-range (800-1000 nm) but appear colorless transparent in the visible range. Does anyone know if there is such an IR-absorbing additive on the market?