Re: Printed Circuit Board Supplies

paul@... wrote:

>
> There were some articles in Nuts and Volts some years ago about making
> multilayer PCBs using laminated solder mask and conductive ink and
> they claimed the equivalent of plated through holes. I've always been
> intrigued by that, but I have never heard from somebody who actually
> did the process and the company (Green Circuit) no longer has a mention
> of that process on their web site.
>
> Anybody else hear of this, or is this just a fading figment of my
> imagination?
>

Yes! This is called polymer thick film circuitry. In the eighties
I was new product manager of one of our divisions that does
this. I developed our proprietary conductive inks for the
process.

It is typically:

1) screen printed

2) not directly solderable

3) higher resistance than copper traces

We still manufacture such products, but usually make
thru holes by coating the walls of punched holes with
the polymer thick film, which connects copper on the
two sides. Components are soldered conventionally.

Many automotive and high volume consumer electronic
products are made this way.

You can read more about it at:

http://www.itwchronomatic.com
--
Leslie M. Watts
ITW Advanced Technology Group
(847)657-4559
http://www.netcom.com/~leswatts/leswp.html