Electronics Forum | Wed Aug 17 13:57:27 EDT 2005 | ppwlee
We have encountered what appears to be mask discoloration after wave soldering. The areas of concern coincide with the areas that were exposed selectively by fixtures during wave soldering, dominated by one date code of PCB with a slightly different
Electronics Forum | Fri Aug 07 01:02:51 EDT 1998 | zeek - just wanna to get a word in here
| | I am looking for advice or information from anyone about the possible reliability problems associated with epoxy on solder pads of discrete devices. Will the epoxy expand and lift over time, Will there be adverse reaction between the solder and t
Electronics Forum | Wed Jun 22 15:03:12 EDT 2005 | patrickbruneel
The only thing ammonia can do is tarnish copper and make it more difficult to solder. And the higher temp in lead-free will discolor the latex (giving it a sticky surface), but the functionality of the mask will be intact. There should be greater co
Electronics Forum | Fri Apr 03 08:22:36 EST 1998 | Scott Cook
| At this moment in time we are using water soluble solder paste on our PCBs these are cleaned using water only, agitated with ultrasonics. After drying a white/grey residue is left around solder joints. Reflow profile is fine and a reliable wash pro
Electronics Forum | Sat Aug 15 06:29:40 EDT 2009 | abeasia
Help, experiencing discolor of a white solder resist paint after reflow of 250 degree, it turned yellow. Have tried many paints, no luck. Anyone knows one that wouldn't change color and holds the white nicely? Thanks for your support in advance.
Electronics Forum | Wed Sep 09 12:20:28 EDT 2009 | richardli
What is the cause of this discoloarion? Soldermask masterial wrong? Thanks.
Electronics Forum | Sun Aug 16 16:01:06 EDT 2009 | davef
White, lead free * Taiyo America PSR-4000 LEW1 * Huntsman (formerly Vantico, formerly Ciba Geigy) Probimer 77 white solder mask Also, search around LEDs Magazine [ http://www.ledsmagazine.com/ ]. White solder masks are often used as a reflective ba
Electronics Forum | Sun Aug 16 19:46:48 EDT 2009 | abeasia
Hi Dave F. Thanks for the suggestion, will give it a try. With Appreciation, ABE.Asia
Electronics Forum | Fri Sep 18 09:25:16 EDT 2009 | ysutariya
There's not really a good answer except that I think that the industry wasn't really prepared for such an increased use of white soldermask combined with the importance of using the white as a reflecting surface. Essentially, the resins commonly u
Electronics Forum | Sun Aug 23 11:42:01 EDT 2009 | ysutariya
Hi Dave, I haven't tried the Probimer yet, but the Taiyo ink didn't hold up too well. As a PCB fabricator, finding a white soldermask that has good trace coverage and survives 4X solder immersion (HASL) is like the holy grail of white soldermask.
