Electronics Forum | Sat Mar 04 13:26:41 EST 2006 | jldowsey
Something unusual happened yesterday, we reflow soldered two boards with white silkscreen legend, and they came out of the oven with purple silkscreen legend. Not tan or brown from overheating, but purple. The boards were reflowed on their normal pr
Electronics Forum | Mon Mar 06 09:19:50 EST 2006 | russ
I have had the purple silkscreen, I don't remember the exact details but it was from either an incomplete cure or a mixing issue. End result was no problems just looked funny.
Electronics Forum | Mon Mar 13 09:09:37 EST 2006 | russ
Our PCB also had this process.
Electronics Forum | Sun Mar 12 18:20:08 EST 2006 | jldowsey
Thanks Russ. As it turned out, it was an incomplete cure at the fab house. Rhey sent another fab over from the same lot that had sat for 3 more days, and it came out lavender instead of purple! have a good one!
Electronics Forum | Mon Mar 06 07:42:48 EST 2006 | davef
Epoxy inks tend to be more resistant to discoloration than the acrylics that are used more widely now. The acrylic-based inks vary in their ability to maintain color after heat cycles. The technical data sheets from the ink supplier should indicate:
Electronics Forum | Sun Mar 12 19:09:45 EST 2006 | cmiller
We had the same issue on a batch of boards and the board house concluded it was because they did the sikscreen before the imersion gold. (which was done out of house-which is very undesireable). I never knew if this was really the case but thought I
Electronics Forum | Wed Oct 23 14:33:44 EDT 2002 | lhoang
Any one encountered the problem such as poor conductivity when the silkscreen mis-registrated on the solder pads ? Thanks; Linh
Electronics Forum | Sun Nov 03 08:28:29 EST 2002 | davef
We have had poor solderability from silk screen being on pads, but have never measured the conductivity.
Electronics Forum | Mon Apr 12 19:28:26 EDT 1999 | Tom B
Netters, When I reflow a PCB there is a discoloration of silkscreen and mask. It appears if Profile is too hot! But I dont think so, maybe I'm wrong? 1. Kester 293 no clean 2. 2.1 C/s for 30s to 150 C 3. .5 - .7 C/s for 60s to 185 C 4. 1.5 C/s u
Electronics Forum | Wed Jul 18 03:57:15 EDT 2018 | cannizzaro
We use eagle for PCB prototype design but it does not have in Gerber CAM scripts by default, when we export the Gerber, layer seems to be wrong place. I want ask you how I can do proper Gerber output for bottom silkscreen as long other layers (mask,
