Thanks everyone for their responses. They have been very helpful. Now that I know what we are dealing with I have a second question or problem. Occasionally we have panels of copper on kapton where we get patchy areas that will not etch. There is little rhyme or reason to the occurrence- sometimes on single sided, sometimes on multi-layers. In addition the next batch of panels in the process are fine. Is it possible for the anti-tarnish to be heavier in some areas so that a normal micro-etch process  before film lamination will not remove all of the coating? Thanks again.

Steve Kelly

 

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Rudy Sedlak
Sent: Friday, October 03, 2003 12:13 AM
To: [log in to unmask]
Subject: Re: [TN] Anti-tarnish on copper

 

The anti-tarnish on copper foil can be anything, an inorganic chromate conversion coating...at one time, they all were of this type... or organic, triazoles, or imidazoles, etc.

No spec...thickness is immeasurably small...in some cases approaches a monomolecular layer...

Are you looking for a test for presence of one?

Rudy Sedlak
RD Chemical Company

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