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 | 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 | 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 Sep 08 05:17:04 EDT 2010 | eddtsk
Hi, ran across a batch of PCB that has white silkscreen during receiving but turns purple/pink after our reflow process. SEM/EDX test can show there is no significant different element between the white and purple silkscreen. Can any help advice what
Electronics Forum | Wed Sep 08 20:14:27 EDT 2010 | eddtsk
Hi Davef, ues, its ENIG. But do you know what the causes this? We send the board for testing but finds nothing defferent chemically between the white and the purple silkscreen. The supplier claim that its our process that is caused the changes.
Electronics Forum | Thu Sep 09 13:25:22 EDT 2010 | eezday
I've seen the purple silkscreen before on ENIG board built with PbSn process. I would think that if temp is the issue the lower process temp would not have caused the purple ink. I remember that the flux I used was water soluble and I attributed th
Electronics Forum | Fri Sep 14 17:22:54 EDT 2007 | golff
I have a changed on the white silkscreen to pink or purple. Do anyone come across with these problem before?
Electronics Forum | Wed Sep 08 15:21:31 EDT 2010 | davef
ENIG boards, correct? If so, you'll find that purplmation of your silkscreen has nothing to do with your process and everything to do with the quality of your in-bound boards.
Electronics Forum | Wed Sep 08 21:17:05 EDT 2010 | davef
Technical data sheets from the ink supplier will: * Describe testing has been done * Recommend to their customers the limits of exposure to thermal, chemical, and mechanical conditions.
