Anti-Fogging Treatments for New Masks. (a comparison of techniques)

[lowviz]

OK, here are the 'magnificent seven':


These (and a few more of mine) have gone through 'hell in a handbasket' together and survived.

Fresh out of the clear household ammonia soak, headed to the dishwasher (as soon as it is free) for a final clean and dry, box, address, and ship.

Aside: The background in the above pic isn't accidental. I was to talk about something, non diving, that I was passionate about, there it is. -I just couldn't cut the one-breath, no push-off, entire length of pool underwater swim. So no point in volunteering. (passed the fish test <with flying colors> though)

 

[lowviz]

I've begun to seriously re-read this entire thread in preparation of a final write-up. Others may wish to continue their own tests/observations in this thread.

Note that the original scope of this investigation was confined to frameless masks. However many have tried household ammonia on other masks. Not all trials turned out well. There were many reports of 'hard plastic' mask failure due to household ammonia. Here is the best that I can offer. Please note the compatibility chart for 10% ammonia solution:

Chemical Resistance Chart for Plastics | Chemical Compatibility

It appears that acetal and polycarbonate plastics should not be exposed to household ammonia. In other words, household ammonia is best reserved for frameless silicone/glass masks. Such other masks (hard plastic) were outside the scope of this investigation, however, others have already tested and reported on such masks. We gain additional insights at their expense.

Suggestion: If you want to ammonia treat a removable lens mask, then first remove the lens and be certain that it is uncoated glass and not polycarbonate.

We press on...

 

[RayfromTX]

Often people don't know that their lenses are removable. All of the masks that my wife and I use have a small plastic piece on the front of the lens that is removable with a small sharp tool. After that retainer is removed, the lenses and the silicone skirt are removable from the plastic frame. Be sure and investigate what you actually have before soaking in ammonia.

 

[АлександрД]

Here is the best that I can offer. Please note the compatibility chart for 10% ammonia solution:
Chemical Resistance Chart for Plastics | Chemical Compatibility
...

After this table is understood, we should made our equipment from the Teflon(tm) (aka PTFE) only

 

[lowviz]

Yes АлександрД, but teflon is not a hard plastic and deforms under continuous pressure.

Acetal and Polycarbonate have wonderful properties but neither likes ammonia.

PEEK is an amazing plastic. (PEEK Material & Properties | High Temp, Chemical Resistance | Curbell Plastics) Unfilled, it is lovely to machine, but it is expensive...

 

[lowviz]

Bad news and good news.

Bad:
See post #841. One last soak in ammonium hydroxide solution and they all failed at the strap adjusters:



Good:
So the problem is that we need ammonia on the inside of the lenses and nowhere else on the mask.

PUBLIC NOTICE:

I have purchased FOOD GRADE ammonium carbonate and bicarbonate. I fully expect to be able to make a paste of an ammonium salt that will condition the glass surface to make it hydrophilic without damaging other parts of the mask.

This approach is now unpatentable as it is public knowledge, a ScubaBoard research project for the greater good.

We press on...

 

[chillyinCanada]

Hmm, the "greater good". Doesn't seem to be too good for the masks.

I'm going to stick with the old ways thus keeping all of my masks in good working order.

 

[-JD-]

Bad news and good news.

Bad:
See post #841. One last soak in ammonium hydroxide solution and they all failed at the strap adjusters:

View attachment 685140

Good:
So the problem is that we need ammonia on the inside of the lenses and nowhere else on the mask.

PUBLIC NOTICE:

I have purchased FOOD GRADE ammonium carbonate and bicarbonate. I fully expect to be able to make a paste of an ammonium salt that will condition the glass surface to make it hydrophilic without damaging other parts of the mask.

This approach is now unpatentable as it is public knowledge, a ScubaBoard research project for the greater good.

We press on...

I am not sure of the relative densities and miscibility nor happen to have any household ammonia handy to test this, but could vegetable oil be used as a barrier to evaporation? Pour in a thin layer of the ammonia, then carefully, some oil and let it sit ... no exposure of the plastics.

 

[lowviz]

Hmm, the "greater good". Doesn't seem to be too good for the masks.

I'm going to stick with the old ways thus keeping all of my masks in good working order.

Correct, not at all good for the masks. Aqueous ammonia solution is too damaging to hard plastics to be recommended. It is, however, perfect for conditioning a hydrophobic glass surface into a hydrophilic glass surface. So, good for glass but bad for mask.

The old ways of conditioning are abrasion and flaming. Both are damaging to the lenses but not the mask. I press on in order to take advantage of ammonia without subjecting any parts of the mask to this chemical, just the inner lens surfaces. I'm looking for a process that can be done in the open air so that any small amounts of released ammonia gas can quickly diffuse away.

I am not sure of the relative densities and miscibility nor happen to have any household ammonia handy to test this, but could vegetable oil be used as a barrier to evaporation? Pour in a thin layer of the ammonia, then carefully, some oil and let it sit ... no exposure of the plastics.

I understand that approach, but it seems too messy to become popular. Wikipedia ammonium bicarbonate. My current focus is to add crystals of ammonium bicarbonate to gel toothpaste. This would be done directly on the lens surface. The toothpaste will enhance decomposition of the ammonium salt into low levels of ammonia while keeping the active compound where it is needed. (so the 'theory' goes...)

 

[-JD-]

But wait, ammonia and oil is just so much easier since they are grocery store items, and the last step is the dishwasher so cleanup won't be too bad.
Since I'm going to Giant today, I'll give it a try anyway ...

OK, WTH! They don't have ammonia?!