Joel:

We have seen the problem of Shadow plating becoming greater and greater, and
incidental to some other researches that we have done, know a lot about it.

The problem is caused by the substrate reacting with the catalyst, and forming
insoluble Palladium compounds.   When the palladium Compounds get into the EN
bath, they are reduced by the hypophosphite to Palladium metal, which then
catalyzes the EN plating.

What to do?

We have solved it, and in fact have a PCB shop using the process.

We have developed a catalyst that will only catalyze Copper.  It binds the
Palladium so tightly in solution (key word :"solution", not colloid) that it
will not react/bind to substrate, and will only deposit on Copper.

Would be happy to send you a brochure on this that will explain everything.
The neat part of this is that you can continue using your current EN and Au
bath, only change required is in the catalyst.

Better things for better living.... (Thank you Dupont)

Rudy Sedlak
RD Chemical Company
Mountain View CA

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