In a message dated 4/27/99 11:21:25 AM Pacific Daylight Time,
[log in to unmask] writes:

<< There was a company in Massachusetts years ago that could rework
 unassembled PC boards using a copper conductive ink process
 instead of discrete wires. This process was automated using a
 screening, baking and surface finish preparation process. Large
 quantities could be processed at fraction of the cost of adding wires.

 I think it was call "Wire Ink". Is anyone using a PCB rework process
 like this?

 Thanks in advance,
 Doug >>

Hey Doug!

I think you may have been referring to a company called "Additive
Processes"...they're actually in New Hampshire. You can visit their WEB site
at    http://www.additive.com

Their process is somewhat like what you're referring to, but a little more
involved than that. I've pasted the opening info from their WEB page below.

Steve Gregory

***************************************

The Additive Process

The Additive process maintains board integrity, flexibilty, and
manufacturability, and meets the latest UL standard 796 requirements for 94VO
boards and customer long-term reliability requirements. The process has six
primary steps:

1. CAD Design - CAD data is downloaded and an optimal ECO routing is created.

2. Etch Cuts - traces are deleted and designated pads are isolated, including
inner layers.

3. Protective layer - a protective epoxy is applied. This layer creates a
known surface and masks the customer's circuitry. It also compensates  for
possible breaks in the customer's solder mask, and coats other surfaces in
the event that the new circuitry runs adjacent to existing vias or solderable
surfaces.

4. Copper Ink - a sophisticated polymer thick film system containing only
copper is applied. This layer is thermal-set, and does not degrade with
additional heat cycles. The copper ink is robust enough to withstand all
automated assembly processes and product life testing.

5. Solder Ink - an SMT-compatible solder application is fused to the copper
ink layer.

6. Test/Certification - new circuitry is carefully tested to ensure its
compliance with specifications.

Optional Step - Final Line Mask - an optional protective polymer provides
additional stability to the completed process.

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet 
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################