Hello all, Has anyone used Kester 2331-ZX water soluble flux on selective soldering and expirienced a white film after soldering. I have seen this on and off for a few weeks now and believe it is a chemical reaction with the solder mask or improperly cured solder mask. After wash i can take the hot air gun and completly make it dissappear, but can put in a oven at 150C for an hour and it does not do anything. Looking for any suggestions on cause, removal or testing.
Yes, we have had this happen with certain solder masks over the years. Hot air gun is the best solution we can find if the oven doesn't do it. Back in the day when we had a vapor degreasor, freon based solvents would also remove the clouding. Let your fab supplier know. I would change your mask or fab vendor of it happens again. Also check with your Kester sales rep. i have been aware of this problem for over 15 years.
Thanks Dennis, The fact that someone other than myself has experienced this is good to hear. Solder mask type should be spec'd all the same through out the many board suppliers we use but its worth the check.I have checked with kester but am still awaiting an answer.