Just my recent quick and dirty experience (2-9-23). Keys from a Commodore 128 yellowed about like the ones in this video. Just dipped each key in 40 strength peroxide cream. Placed on a serving tray and covered with saran wrap. Sat the tray in the sun for about 8 hours each on 2 days. Temperatures were in the high 30's. Afterwords all yellowing was gone. For what ever its worth.

Thanks, always on the look out for the best way to do this.

Fascinating tests. It's interesting that it looks like sunlight yellowed the keys originally, but sunlight is needed again to reverse the yellowing.

@Houshalter

2 жыл бұрын

There's another video where someone uses just sunlight and no peroxide and it seems to work, just slower. It's apparently not sunlight causing the yellowing on it's own? I don't get it

@pityuszka100

11 ай бұрын

​@@Houshalter It is the sunlight. UV component of the sunlight causes the molecules in the plastic to break apart. In case of ABS plastic (used widely in for consoles and electronics) the bromine (it is added as flame and fire retardant) and the rubber (added so the plastic is less brittle) boosts the yellowing. Deep chemistry: the UV breaks the bonds, create free radicals, unrolls organic rings in the butadiene copolymer etc, and creates some crazy conjugated compounds that absorb more bluish light of the spectrum, creating yellowish color. The process of retrobrighting (de-yellowing these plastics) uses hydrogen peroxide which restores the chemical bonds (removing the conjugated bonds) and gets rid of the behaviour of absorbing blue color (and causing yellow color). In nutshell.

Great video and experiment

Após usar realizar o processo de retrobright basta apenas utilizar spray de verniz incolor fosco com proteção UV, o amarelado não volta mais, é necessário realizar 3 aplicações para criar uma camada de verniz forte.

Hey Hutch, what about Calcium Carbide? I have a toy cannon that holds water in a chamber and when you add calcium carbide it reacts to create acetylene. (A small flint striker causes it to go bang.) - I'm no chemist but isn't acetylene mostly hydrogen?

@zachz96

Жыл бұрын

No. Acetylene is C2H2

I watched Jeff's video. It's very good and worth watching. His thesis is that H202 is just bleaching the surface of the plastic. If he's right (and I suspect he is), then it's not surprising that not much happened with distilled water, H2 water and water with Mg; it was just bleaching from the sun's UV reduced by the filtering effect of the plastic container plus clouding of the water with the Mg tablets. It seems the way to go is with H202 and heat and/or UV and the H2 idea is little more than wishful thinking.

@HutchCA

Жыл бұрын

Yes. I believe any lightening in the plain water was simply sun bleaching. Hydrogen had no effect as far as I can tell.

2:20 I don't know how you kept a straight face while opening the can of erm... *Water*

Saw an interesting experiment the other day. They used pedastals to hold the object above the h2o2 line and used the gases. Due to h2o2 causing plastics to become brittle.

@HutchCA

Жыл бұрын

I figure since the plastic is waterproof and not porous, it can only affect the surface of the plastic. If it does cause plastic to become brittle, it would only be the thin surface layer, not all the way through.

@az_tinkerer_gamer

10 ай бұрын

@@HutchCA i did have a bowl sit out in the sun too long w/ h2o2, was noticeably more weak/brittle. But ya may have been exascerbated by the sun as well.

@HutchCA

10 ай бұрын

@@az_tinkerer_gamer I suppose if there are cracks in the plastic, even microcracks, the solution could seep in there and make the crack worse.

The result is: Only the H2O2 works quickly ...

What I noticed is the keys were just chucked into a container and liquid sloshed in and containers capped but no attempt was made to control whether keys were right side up or upside down. The right side up keys would have been exposed to more gas than others with their tops being submerged in liquid. Not very good controlled environments. FWIW I just had cataract surgery on both eyes and believed I could see a bit of difference in lightening affect between all keys. I have a toilet seat and lid that I was just looking at yesterday thru new eyes and the items look grossly yellowish and needs to be retrobrightened which I'll give this a shot at.

I always use hydrogen peroxide and heat when retrobrighting. About 50°C/120°F in the oven for 4-5 hours does the trick every time. No need for sunlight or complicated UV setups, that probably don't penetrate the liquid that much anyway. My guess is thatif you'd cool the solution when using UV-lights basically nothing will happen. Just put it in the oven, folks :)

@falksweden

2 жыл бұрын

@@HutchCA I'm living in Sweden and we seldom have that kind of temperatures in the sun, that's why I tried the oven out :)

@bloodieown

2 жыл бұрын

I'm planning on doing this to some keycaps, but im wondering how long the retrobright effect lasts on the keycaps? Do you have any indication on how long I can use the caps before they look yellow-ish again? Or is it durable enough?

@falksweden

2 жыл бұрын

@@bloodieown I don't know. None of my machines that I've retrobrighted years ago has gone yellow again.

@bloodieown

2 жыл бұрын

@@falksweden That's good to hear, I guess ill give this a go then. When you put the plastic bin in the oven, do you seal it at all or do you leave the top open?

@falksweden

2 жыл бұрын

@@bloodieown I try to seal it as good as possible to avoid that the cream dries out, and about every 30 minutes I "massage" it.

I use 12% Hydrogen Peroxide but I don't dilute it. It works well within a few hours.

Do the keycaps not need to be fully submerged in hydrogen peroxide?

@HutchCA

Жыл бұрын

Not in my experience. I've never bothered with trying to keep anything submerged and using a sealed container helps with the solar heating. I could be wrong but as long as they are sealed mostly air tight, I believe it's the gasses that do the job. Specifically the Oxygen released from the Hydrogen Peroxide.

Un apunte. Los recipientes de plastico suelen hacerse con aditivos que actuan como filtros ultravioleta. Ponerlos al sol para que la luz ultravioleta actue, puede no tener los resultados esperados y requerir exposiciones mucho mas prolongadas.

@HutchCA

8 ай бұрын

I believe it's mainly the heat that causes the reaction.

Science!

is it possible to reuse hydrogen peroxide for another cleaning project?

@HutchCA

Жыл бұрын

Yes. It will lose some potency over time but I save it to re-use. Best to store in a cool dark place.

@AvivOz

Жыл бұрын

@@HutchCA thank you

Does your plain water have chlorine in it?

@HutchCA

9 ай бұрын

No, we're on well water, which has a lot of iron and manganese.

@HutchCA

9 ай бұрын

Actually, IIRC, I used bottled distilled water in this experiment.

Wait...I was never a chemistry wiz in school...but isn't water H2O? As in, water ALREADY has hydrogen infused? ;-)

@GamesFromSpace

2 жыл бұрын

Water is extremely stable, it takes a lot of energy to break apart the bonds between the hydrogen and oxygen. So for our purposes (as meat based lifeforms), there's no available hydrogen or oxygen except what is added to the pure water. It's still BS, of course. If we needed molecular hydrogen for some reason in biology, it's present in ordinary air at 0.6 ppm

@cbmeeks

2 жыл бұрын

@@GamesFromSpace yep. My original comment was a poor attempt at being funny.

Is not water by definition "hydrogen infused"? It is the H in H2O. Just saying.

@HutchCA

9 ай бұрын

In theory, this is supposed to have additional atomic hydrogen dissolved in it, but I don't think water can absorb much hydrogen.