Plating Pd or Au on smooth polyimide films

Q. Hi, I'm having trouble locating suppliers that can provide chemical/electroless deposition method of metallizing smooth polyimide films (e.g. Kapton).

I need to find a chemical deposition method that can catalyze and electrolessly plate a thin seedlayer of either Pd or Au. After that, we will apply/pattern photoresist & through-mask electroplate a few um of Au (creating pads & conductor lines) then microetch the seed layer away. Ideally, the seed layer microetch would not attack/roughen the electroplated Au surfaces.

Does anyone have suggestions for vendors to contact or plating systems that work best? I've already explored our standard suppliers (Uyemura, MacDermid, Metalor, Atotech, Dupont, RBP, Technic) and none have a ready-made solution for depositing Pd or Au on polyimide. I've tried a couple options and both have major issues (low initial and/or retained adhesion, skip plating defects, etc.). Most have well developed options for plating on ABS & other plastics, but not smooth polyimide.