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Subject: Re: Printing pcb patterns negative or positive

From: "Ben H. Lanmon" <bhleavi@...>
Date: 2003-12-20

> "BTW, the screen printing emulsions are negative acting so you
will
> need positive films emulsion side up."
>
> So I guess you are saying that my laser printed PCB patterns (on
> plastic sheets) are positive as is, and I have my terminolgy
> backwards. So I can use these with "negative acting screen printing
> emulsions" to get the silk screens I need to put resist ink on the
> copper which is not to be etched?


I would think that you want a negative to expose your screen which
would be the trace pattern would be clear and all other areas dark
just like a film negative would be.

Ben