What started me looking at this is that I bought a PSOC5 developer board for testing and wanted to hook up an LCD display to it. Sparkfun had some Nokia displays for 2.95 that I wanted to use. The problem is that they have no connectors. Just bare ITO traces, which have an oddball spacing of 1.15mm.
The next issue is to figure out how to bond the connector to the ITO.
3M sells an anisotropic conductive adhesive, but they charge several hundred dollars for a hundred feet. Mechanical would be another option, but I just do not like that in this case.
My thought is to make my own anisotropic conductive using powder coating paint mixed with some conductive powder such as graphite or copper. A combination of heat and pressure would bond the flex connector to the ITO and conductive particles would be trapped between the copper and ITO connectors. Another experiment to perform.
In the mean time, since I just want to play with my LCD and PSOC5 board and not get sidetracked on other things, I am going the silver epoxy route to attach the wires to the ITO.
I will do some more experimenting with flex cables and bonding at some point in the future.
--- In Homebrew_PCBs@yahoogroups.com, Andrew Villeneuve <andrewmv@...> wrote:
>
> This is remarkably useful! I've often wanted to rework flex cables, but it
> had never occurred to me that there was a viable homebrew way of doing this.
>
>
> Let us know how your results look if you repeat with printed traces and
> heated FeCL.
>
> -Andrew
>
> On Sun, Jul 11, 2010 at 5:15 PM, javaguy11111 <javaguy11111@...>wrote:
>
> >
> >
> > A quick check of the archives did not show that anyone had tried this, so I
> > will relay this little test I just did.
> >
> > I was thinking about making a flex ribbon for a small lcd display I bought.
> > I decided to do a quick test with some copper foil tape and 1 mil kapton
> > tape.
> > I laminated the sticky sides of the copper tape and kapton tape together.
> > Since I was doing a quick and lazy test, I just used a permanent marker to
> > create some linear traces like you would see on a regular ribbon connector.
> > Again, because I was doing a very quick test, I etched the traces in ferric
> > chloride that I did not bother to heat, though I did use the bubbler.
> > After about 15 minutes, the copper was etched away sufficiently. The trace
> > quality was low, because of the quick and dirty nature of this test, however
> > the traces were bonded to the kapton tape and were continuous.
> > I was surprised to see that the adhesive on the kapton was still effective
> > in the areas where the copper was etched away as well.
> > With this test, I am confident that this method would be viable for
> > creating custom flex circuit connectors.
> >
>
>
> [Non-text portions of this message have been removed]
>