It evaporates. Maybe not the absolute fastest butt it evaporates plenty fast enuff.
The fastest evaporative contact cleaner I almost exclusively use is, Puretronics Contact Cleaner. Stock No. 3500. Relatively cheap yet absolutely fantastic stuff. :+1: :+1: :+1: :+1: :+1: :student:
One other tip: Take a can of compressed air, hold the can only horizontally, and after ya spray the contact cleaner over your partially dedomed led, give it a blast or two of air.
This will clear out tiny particles of dome material from the phosphor and any remaining contact spray will get blown out too. :+1: :student:
My CRC it’s another old product called “electro”.Not a specific contact cleaner as you said and guarented doesn’t evaporate,infact he still where I had applied
But I”ll try also your method
Finally I can use my chemistry degree. The base of an LED should be ceramic. The dome should be clear epoxy or clear epoxy with bismaleimide-based polymers added for strength and heat resistance. The Phosphorus is probably vapor deposited with Silicon “the element, not the gooey stuff” I’d say some of the harshest solvents out there should be fine. Of course I’ve been out of a lab for 27+ years.
Some datasheets mention the materials used, Nichia’s for example and the dome is made of silicone, Cree presentation about dome and domeless LEDs mentions it too.
Then have at it, the silicone should easily be removed with harsh chemicals without harming the substrata. Less harsh try Vinegar and isopropyl alcohol with good long soaks.
Inspired by this discussion about chemicals and dedoming I did few tests. I put WD40 and brakecleaner in small container. Those small plastic cases that Simon uses when he sends emitters.
I put sliced Xhp70.2’s in both of them. WD40 hardly did anything in 24 hours but brake cleaner did this in 10 hours:
Seems promising. Let’s keep experimenting. (Grey stuff is just leftover thermal paste)
After testing the emitter works fine. Sadly this one has had some strange behaviour before, and after this harsh bath it hasn’t improved. 1 of 4 diodes is cooler colored than the others and it also has afterglow for a few seconds. It’s like 5000-6000K and others are 4000K as they are supposed to be. It also lits up in lower voltages than other 3.
On the subject of aromatic solvents, does anyone know of an epoxy (the cured hard type) solvent?
Have a very small amount to remove from a watch mechanism. Can’t scrape this off and immersion of the whole spring/ escapement is not an option. But I could wrap it in some gauze and light plastic film to let it do its thing.
Tried Methyl Ethyl Ketone (MEK), Acetone (diMethyl Ketone), Methylene Chloride (Acrylic solvent / one of the ingredients of paint stripper).
Google search – bad results; easy to remove uncured resin. Nothing really tested about cured stuff. I mean, isopropyl, methyl or ethyl alcohol, paint thinner (usually kerosene), lacquer thinner (which is mostly MEK but some variants having more volatiles), and citrus-based cleaners as GooGone just makes an oily mess. No success on some test pieces.
Hadn’t tried gasoline – smelly, although very active solvent.
Methylene chloride for Epoxy. 5% sulfuric acid or sodium hydroxide for polyester resin. Dichloromethane warmed to 40C for a few hours. Methyl Ethyl Ketone (MEK) I used for removing cured epoxy on pcb’s. It’s the same chemical your Kidney’s release that make that awful morning piss smell.