Homebrew PCBs

Hi Stefan,

it didn't appear that the nozzles were blocked, unless
by a strange coincidence, every other one became
blocked at the same time. I'll post photos in a couple
of hours after the batteries charge up for the camera.

I did notice some durability problems with the ink.
The printing wwas screwed up on one board with large,
thick blobs of ink. I heated the blobs very well and
noticed that is was very powdery and came off easily
when touched.

I had also tried the Pulsar sponge method of etching
with FeCL. The patterns were wiped away.

Basesd on my textile printing and coating background,
I would say that the Durabrite ink, at least, has a
very weak discontinuous film holding the pigment
particles to the copper. This will make the resist
sensitive to a varity of facotrs. Not surprising,
since it was designed for absorbent paper fibers
rather than copper.

Note: i did not micro-etch with Tarn-x. The
micro-etching process worked to increase the scratch
resistance of the TEFLON used on pots and pans.

To corect this problem on textiles, I would try to
recure the ink and increase the binder levels or add a
catalyst. If that didn't work I would look at the
surface preparation of the fabric, making sure there
were no residual oils.

I'm starting to get the impression that direct to pcb
inkjet printing will be like the Toner Transfer
process, it is do-able, but subtle variations in
tecniques will reduce the reliability. Each person
tryng this process will have to fine tune it for his
conditions.

TANSTAAFL!

Myc





--- Stefan Trethan <stefan_trethan@...> wrote:

> On Tue, 18 Apr 2006 04:54:17 +0200, mycroft2152
> <mycroft2152@...>  
> wrote:
> 
> >
> >
> >
> > The print quality was very good, but I noticed
> that on closer
> >
> > inspection afterward it must have been set on
> draft quality. I could
> >
> > see the individual ink lines making up the
> letters. but I proceeded
> >
> > anyways.
> 
> 
> could also be some nozzles were clogged. It is
> always good to run a nozzle  
> test pattern beforehand, such things often are not
> noticeable on paper  
> because it wicks together.
> 
> ST
> 
> 
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> 
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> 
> 


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