Cleaning Stained Plastic/Ceramic Chips (BJ v7) (2 Viewers)

I rewatched some retrobrite videos from The 8-Bit Guy and I was surprised to see that a no-soak approach where hydrogen peroxide is combined with heat + UV had a positive effect in reversing the yellowing. So, I've currently got a single Borgata $1, suspected with magnets, baking outside in a container half filled with h2o2. We'll see if there's any effect ...

Yikes. I hope not too hot. Good luck!
 
Yikes. I hope not too hot. Good luck!
8-Bit Guy gets to about 130°, but he's in Texas. It's about 90 here today in NJ and I just measured the temperature inside and it was about 100°. But remember, the chip isn't in the peroxide; it's just in the hot air.
 
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Wow ... I was not expecting this! Here are the same chips in the same order as the original post. The chip in the middle is the control chip to which I want to bring other chips into alignment with. Nothing was done with the chip on the left, and the chip on the right was subjected to the science experiment.

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It's hard to capture with the camera, but the rolling edge photo really does show how much of an improvement there was. What was more surprising is that both sides of the chip whitened substantially, even though one of those sides was held up against the lid of the container with a magnet.

That to me says that the gas created from the peroxide was able to work its way into any gaps.

So, have I effectively retrobrited a poker chip? I think so!!!
 
I’m more amazed that the process left the label, metallic and all, completely unharmed.
There was a little bit of something, kind of like a rust stain, on the label when I took it out. It wiped cleanly away. It's almost as if all the staining had condensed into that one spot on the label.

But as far as the label goes, remember that this was not submerged in the liquid. It was simply suspended over it and exposed to whatever gases were created as a result of the heat and UV from the sun heating up the hydrogen peroxide solution.

At this point, I would like to try to repeat the success on the other nasty ass chip in the above photos. So that's what I'm going to attempt tomorrow. If I can replicate the success, then I'll have to devise a way to do chips in bulk.
 
I ran the experiment again with the chip on the left. Same exact setup as last time: placed inside of a sealed glass container that was filled halfway with hydrogen peroxide. A magnet held the chip to the lid so it was not touching the liquid. This time, I left it in the sun for about 6 hours.

The result? Well, it's like 90% better! Perhaps it could go even longer, but I'm pretty satisfied that this method seems to work. And there is definitely no brown stain spot to wipe off. It just magically brightened over the course of the day.

Original​
Retro-Brited​
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So, now I need to figure out a mechanism in order to do more at a time. I suppose I could just use a larger container, and more magnets to hold them up. I could probably get about 10 at a time out there...

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Doing 7 chips at a time.

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I also tried submerging a chip in the hydrogen peroxide. The chip has a crack in it anyway, so I didn't care if it got ruined since I was going to return it on my next trip. To my surprise, the label stayed perfectly intact, and the chip whitened a bit more than the one that was held up with magnets.

Kind of begs the question if I should just give them an h2o2 bath instead of this crazy magnet suspension.
 
Pure h2o2 or watered down?
And how long was the soak?
I started weak with full expectations of needing to go up in h2o2 concentration. This was 3% peroxide (direct from the bottle) without anything added.

Chips go out at about 10am into direct heat/sunlight, and come back around 7pm. So roughly 9 hours; moved once to follow the dayball.

The chips don't go into the peroxide like a traditional "soak", but are suspended in the container with magnets.
 
Did you submerge the cracked chip for 6 hours?
The cracked chip was submerged for about the same amount of time as the suspended chips; 9 hours.

That's when I took it out to inspect it and noticed that there was no degradation to the label and that its whitening was slightly better than the other chips.

It then went back into the peroxide for another entire day just to see what would happen to the label. Nothing happened... It looks brand new.
 
At this point do you think UV actually matters?
Well Mr. Chippitydoodah, you just guessed what my weekend science experiment is going to be.

I'm going to try heated peroxide with no light! My guess is that it's going to work, but possibly not be as effective since the UV might be acting as a catalyst.

Side note: I also tried a submerged chip in peroxide for one day with only ambient light and room temperature. There was no whitening.
 
I've got some extreme staining to clean up on the Las Vegas Club chips I'm gathering so I'm paying very close attention to this thread. Thanks!
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But soak in direct sunlight on a summer day is the ticket right?
Yeah, the chip that soaked definitely whitened really well. Seems like direct contact with 3% peroxide with UV + heat delivers great results.

Tomorrow I'll try just heat to see if UV is a factor at all

I'm still on the fence about a direct soak. The magnet suspension seems safer since I don't know what the long term effect on the label adhesive will be.
 
I've got some extreme staining to clean up on the Las Vegas Club chips I'm gathering so I'm paying very close attention to this thread. Thanks!
Awesome! Looks very similar to what I was dealing with. Using the magnet suspension plus 1 day in sun/heat should really help those.
 
Just to recap, here's a really brief summary of the issue followed by my own tests/results.

The yellowing of ABS plastics is caused by oxygen interacting with one of the molecules in the plastic. The oxygen atom bumps some stuff out of the way, there's a floating free radical, bada-bing, a new polymer is formed. This new polymer is just on the surface of the plastic. It absorbs some visible light (the yellow kind), the rest bounces off, and boom, you have a thin layer of yellow on the surface. Heat / UV can speed this process up, but it will happen regardless.

Retro-briting is the process of undoing this by redoing it. Using hydrogen peroxide, the weak oxygen atom gets busted loose from the peroxide, nudges its way into the yellow polymer, forms yet another polymer (with better bonds!), and essentially bleaches the yellow compound. The new polymer reflects all light, hence it's white. Heat/UV can speed this process up.

So, eventually, this means that it is possible for the yellowing to return as atoms get shared like a cheap hooker. But, at the very least, without direct sunlight and heat, it will take a very long time.

But this also means that it's not the gas (oxygen) by itself which is helping to retro-brite. You can totally submerge the chips in the peroxide with the same (if not better) results.

Method​
Time​
Result​
3% Hydrogen PeroxideVery Long (24+ hours)Virtually no change
3% Hydrogen Peroxide + UV Light (UVA)Long (12 hours)Very Good (VG) Whitening
3% Hydrogen Peroxide + HeatMedium (8 hours)Very Good (VG) Whitening
3% Hydrogen Peroxide + UV-A/B/C (Sun) + HeatShortest (6 hours)Very Good (VG+) Whitening

Things that could REALLY help this process along:
  • Using a higher concentration (like 12%) of hydrogen peroxide
  • Combining a heat source, that is not the sun, along with UVA light (UVC is not the best for plastics)
Here are some of the variations I performed (all with 3% hydrogen peroxide)
  • Sealed glass container in direct sunlight
    • Chips suspended by magnets so they did not touch the solution
    • Chips submerged in the hydrogen peroxide
  • Sealed glass container at room temperature for 24 hours with chips submerged
  • Black plastic container in direct sunlight with chips submerged (basically no UV, but heat)
  • Open glass container at room temperature with direct UVA light for 24 hours

This all kind of needs a formal write-up. But the BIGGEST takeaways are:
  • 3% hydrogen peroxide seems sufficient for this process and seems safe for full chip submersion in the liquid
  • Heat and/or UV speed the process along; either works well, both work slightly better than either alone.
  • 6 hours seems to be where the additional time has a deminishing effect.
What Would I Do in the Winter?
Without a combination heat/UV source like the sun, I would most likely use my UVA lights at room temperature. It would take longer, but the 1 test I ran produced results that I was happy with.

Did You Really Heat Hydrogen Peroxide?

I can just see the headlines now. "East Windsor man blows up house trying to whiten Borgata poker chips. When approached for comment, he was being carried off by men in white coats while yelling at them about the differences between inlays and labels." Yes - I did it heat it; outside on a hot plate. With those loose oxygen atoms, I'm not taking any chances here ... It was heated under an SPF-80 awning in the shade at around 75 degrees.
 
OxyClean (sodium percarbonate) creates peroxide when mixed with water. Did you also try a mixture of OxyClean on the chips? I know it can harm hotstamps, so I’m unsure how it would affect the label. If it works, it may be a faster process with a hopefully similar result.
 
So would placing a layer of chips on a baking sheet then covering with peroxide and set in the sun for 6 hours be the best way to bang out the most chips? Would more heat be needed by maybe covering with saran wrap?
 
OxyClean (sodium percarbonate) creates peroxide when mixed with water. Did you also try a mixture of OxyClean on the chips? I know it can harm hotstamps, so I’m unsure how it would affect the label. If it works, it may be a faster process with a hopefully similar result.
I actually did buy a tub of OxiClean in the event that the hydrogen peroxide did not work. I'm hesitant to try it since it's got more chemical stuff going on and is more likely to cause reactions with the inlay or the non-yellowed parts of the chip.

But you're right, oxygen is right in the name, so it probably works on the same principles. It essentially bleaches the chemical compounds which are absorbing light in the yellow/red spectrums, creates stronger bonds, and converts that top layer to something that reflects all light (white).

I could do a controlled test on one of my bad chips with OxiClean to see how it compares.

So would placing a layer of chips on a baking sheet then covering with peroxide and set in the sun for 6 hours be the best way to bang out the most chips? Would more heat be needed by maybe covering with saran wrap?
Saran wrap wouldn't do much on a baking sheet in my opinion since the purpose of it would be to create some kind of faux greenhouse effect. Instead, I would expect Saran wrap to work on the black plastic tub the best. The more open air space that it has to trap the gases, the better.

With that said, the baking sheet principal might work fine, but they would only be a very thin layer of hydrogen peroxide covering the chips. To be honest, in my latest tests, I used a glass container and had about 20 chips in there. They were on top of each other and definitely not uniformly spaced. But the result was the same... Pretty much uniformed whitening.

I also like the idea of a covered container. The direct sunlight is absolutely not necessary. Indirect sunlight provides enough UV and heat. Additionally, ABS plastic does not play nicely with UVC, making the top layer more brittle.

Side Note: with a direct submersion method in the hydrogen peroxide, I was expecting to see some kind of fading of the teal spots on the chip. However, I did not see any. Perhaps if you compare them to a brand new chip that has never been dirty and never been brightened, they might be a tad darker, but it certainly doesn't look like the colors were impacted if you're just looking at the chips themselves.
 
Sure @TheBigTater. Actually, your question brings up something I wanted to mention but forgot to. I originally did the magnet suspension method to prevent the chips from being submerged in the hydrogen peroxide. It would suck if I ruin my chips. I honestly thought that the damage would be to the label.

Even though I've determined that my particular chips seems safe to submerge in the peroxide, when starting to try a retrobriting on your own, you might want to try a test chip first to see if it has any adverse effects. If you don't feel comfortable submerging it in the solution, then the magnets could be a good alternative.

Also, if your chips have a metal slug inside of them, you probably only need to use a single magnet, not two.

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As you can see, the chip is basically the meat in a magnet sandwich. Don't get me wrong, when I took the chip out of the container, it was covered in water. The evaporation process and then subsequent condensation does not prevent the chips from being wet.
 
This is very cool and I will have to try it. I've seen people get excellent results retro-briting other plastic things, and have wondered myself whether this would work on yellowed-white plastic chips.

However, as a color nerd, I have to point out that you have this backwards:
It absorbs some visible light (the yellow kind), the rest bounces off, and boom, you have a thin layer of yellow on the surface.
It essentially bleaches the chemical compounds which are absorbing light in the yellow/red spectrums, creates stronger bonds, and converts that top layer to something that reflects all light (white).
Things that absorb yellow light do not look yellow. Things that reflect yellow light look yellow. But the point is made, that the yellow color arises from degradation of the plastic, and you can undo that chemical degradation with UV + hydrogen peroxide.

Again, nice work!
 

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