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

[lowviz]

Have you tried mixing the ammonia with powdered gelatine, water and glycerine to create a soft jelly "gel" ?

No. I take peer-reviewed publications at face value. I don't have time to re-affirm failure:

US3172860A - Aqueous high-viscosity ammonium hydroxide composition - Google Patents

“Strong reagents such as ammonium hydroxide have a multitude of uses such as, for example, cleaning agents in the preparation of surfaces prior to the application of protective coatings and in alkali cleaning of surfaces in general. However, the fluidity of these reagents very often limits their utility. Increasing the viscosity of these reagents, even to the point of gelation, would be desirable providing that the reagent remained reactive and the high-viscosity state persisted for practical lengths of time. Attempts to produce such high-viscosity reagents with conventional thickening agents such as gelatin, casein, gum arabic, and the like, have been unsuccessful. Either the reagent will not gel in the first place, or if it does so, it is so short-lived as to have no practical value.

Accordingly, it is a main object of the present invention to prepare high-viscosity ammonium hydroxide compositions.

It has been discovered that high-viscosity ammonium hydroxide solutions can be prepared by incorporating therein a thickening quantity of poly(alkylene oxide) having a molecular weight in the range between about twenty thousand and ten million.”

@Umuntu, really good suggestion though!

 

[Umuntu]

No. I take peer-reviewed publications at face value. I don't have time to re-affirm failure:

US3172860A - Aqueous high-viscosity ammonium hydroxide composition - Google Patents

I'm not sure that I would regard a Patent application with the same degree of academic respect due to a proper peer-reviewed publication. There is an interest in talking down other approaches in order to boost their own patent application.

Powdered gelatin and glycerine are inexpensive. I have some at home and will give it a try tomorrow. It just needs to be a thick carrier of the ammonia.

 

[lowviz]

Powdered gelatin and glycerine are inexpensive. I have some at home and will give it a try tomorrow. It just needs to be a thick carrier of the ammonia.

And last in a gelled state for a week...

I'll do the baby diaper thing in the meantime. I appreciate the parallel trials!

 

[Boston Breakwater]

Yes, you did say that. My bad. Apologies.

Thanks very much. I appreciate that.
Cheers.

 

[Umuntu]

And last in a gelled state for a week...

I'll do the baby diaper thing in the meantime. I appreciate the parallel trials!

Before doing any mixing, I decided to do a quick google search of "ammonia gelatin" ... I think whether it lasts in a gelled state is the least of my concerns now.

Needless to say, I won't be playing with this in the kitchen

 

[tridacna]

Before doing any mixing, I decided to do a quick google search of "ammonia gelatin" ... I think whether it lasts in a gelled state is the least of my concerns now.

Needless to say, I won't be playing with this in the kitchen

Congrats! Your internet searches, phone calls and movements will now be tracked worldwide for perpetuity.

 

[Daebado]

I feel like this has become a cliff hanger... just waiting to get to the final outcome... only I forgot where I put the book and now I may never know how it ends!





Or are we done?

 

[tridacna]

I feel like this has become a cliff hanger... just waiting to get to the final outcome... only I forgot where I put the book and now I may never know how it ends!

Welcome to the thread. Moves along sinusoidally. Needs to bump to get things going...





Or are we done?

 

[Daebado]

Thanks for welcoming me to the thread but this is not my first post in this thread. And yes, I was hoping the "bump" would help jumpstart it again.

As an aside, I have a new Atomic Subframe mask that I just put new lenses in (had readers installed on them) and my first trip in the pool with it, it fogged like crazy. I thought maybe since the lenses weren't in the mask when it was made that it might not have the fogging issues of a frameless. Wrong!
So, before hitting the lake this past weekend, I took my lenses out, flamed them, reinstalled them and ran the mask through the dishwasher. Did the same with my wife's new frameless mask (can't remember the brand).
I'm happy to report that both masks performed flawlessly during our lake dives!
I'm still very curious to see how the rest of this thread's experiments turn out but for me, I may have found my final method. I mean, if it works, why keep going, right?

 

[lowviz]

I feel like this has become a cliff hanger... just waiting to get to the final outcome...

Like I posted earlier, knowing when to quit is an art. I don't want to drag this out, but there are a few more bits of work to be completed.

Much going on behind the scene. Tried a huge range of concentrations of the (miserable) slime polymer with ammonia. The two are compatible but the slime doesn't keep the ammonia from evaporating at any concentration. A spin-off is that polyethylene glycol (PEG) is an inert thickening agent. It is a mess to remove from hands and glassware. This suggests that a bit of PEG added to 10% baby soap might just be a really good anti-fog agent. (maybe someone will market it as Baby Spit?)

I'm now convinced that all current success is all about ammonia's ability to re-structure a glass surface. This also appears to be a self-limiting process so you can't over-do the ammonia. @lexvil, in reply to one of your questions way upstream in this thread, yes, an ammonia-treated lens passed the ball-drop test. (n = 1 trials)

This puzzle piece just didn't fit with all the other observations:

Recently I had my wife mask that was VERY resistant to defogging. The dive store kept doing things that were not working (defog, shampoo...). ...//... I took some soft scrub and some very very fine sand (with soft scrub) and gently scrubbed the inside of the mask. It worked. ...//... If I put the mask under a microscope, I will probably see scratched. By naked eye, it looks good.

@Compressor, thanks for this observation. It now makes sense: https://www.annualreviews.org/doi/abs/10.1146/annurev.ms.02.080172.002525

Look at what clean 'glass on glass' friction does. It is called 'stick-slip' microfracturing:

This compares well to the microstructuring that ammonia does to a glass surface. So, I've learned that a perfectly flat and clean glass surface in air produces all sorts of reflections. If the glass surface is 'trashed' at dimensions that are just smaller than the wavelength of incident radiation (for us, the visible spectrum), then the reflections are reduced or eliminated while transmission of light through the glass is increased. You can see this in any art musuem, the paintings are all protected by glass that you can't see as it doesn't reflect.

It looks like the very fine sand that you added to your Soft-scrub did a very similar thing that ammonia does.

In addition (quoting from the same paper concerning attacks on a glass surface):
"Inorganic polyphosphates have the same ion-sequestering property, and consequently the same tendency to attack glasses. This attack is particularly severe in automatic dishwashers, where high temperatures and strongly alkaline detergents are the rule."

So a household ammonia treatment and your dishwasher seem to be well suited to each other as yet another good solution to mask fogging. I'm pretty sure the best way to clean, microstructure, and hydroxylate the glass surface is to first put the new mask into a dishwasher, then into a closed container with just enough household ammonia to assure coverage of the inside of the mask lens (leave it for 3-7 days), then use a dishwasher as needed to refresh the mask. That regimen should remove the need for high-octane mask defoggers. I still like either spit or baby shampoo.

Do what works best for you...