8 hours in acetone and the PVC residue is still there...

Guess this poster has lots of free time on his hands or perhaps is an investor in a chemical company producing acetone.

FULL STRENGTH MS-70!

 

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It probably removed the PVC residue long ago, you're now hoping it will remove PVC damage, and it won't do that.

 

I use this double-shot glass with rounded bottom, never thought the bottom of the glass is literally the perfect size for a morgan
I've tossed it back in with acetone. Wont' touch it until this time tomorrow! Although like Insider mentioned, that large neck spot really looks like it's gotten its claws into the metal pretty good already.

 

Haha, although tbh if the PVC has eaten into it already MS70 probably wont hurt

 

I guess 35 years in a PVC flip will do that... :'(

 

I guess Insider mentioned MS70 as a solution for PVC (I don't know, I've had him on Ignore for a long time)? Don't believe him. MS70 contains nothing which can affect PVC plasticizer damage.

Even if the PVC has already permanently damaged the coin, everything you see as "green" should be removable (that's the "residue"), and until it's gone the damage will progress. It's been my general experience that the darker the green, the greater the need for worry, although the sheer square space occupied by the patch on the neck is obviously a concern.

 

PVC plasticizer residue contains hydrochloric acid, it's the acid that causes the damage. Because the coin was exposed so long to the acid, it has etched the surface and created verdigris by further reacting with copper in the coin. Now that you've removed the organic residue, you need to remove the verdigris left behind as it is INSOLUBLE in acetone or any other organic solvent.

 

Acetone should not be used in an open container. It evaporate rapidly and will redeposit any dissolved residue right back onto the coin.

 

I had that issue when the first couple of times so now I just put a book on top of the open glass!

 

That creates something really flammable. Use a piece of glass as a cover instead.

 

The GREEN residue is the PVC. When it is removed there may be irreversible damage to the surface underneath. Depends on several factors.

 

That's interesting; you got me looking into the reaction to see how it worked that way. Thank you. It modifies my thinking on the subject.

 

Hah! I've never seen that shot glass before. I guess it implies that the Air Force can outdrink the Navy, Army and the Marines. I don't see the Coast Guard listed. They must be wimps.

Chris

 

@ SuperDave has pontificated more OPINION that should be ignored. That's a good one, "ignore the messenger NOT the opinion.

He has posted: "I guess Insider mentioned MS70 as a solution for PVC (I don't know) I'll agree 100% with that. YOU DON'T KNOW. Have you ever tried using MS-70? Of course not - as you have continued to recommend acetone to members for as long as I have been around. "I've had him on Ignore for a long time)? Don't believe him. MS70 contains nothing which can affect PVC plasticizer damage."

BIG CLUE: Did you happen to read this from the OP's post: "Acetone should work for removing it, but 8 hours of soaking later [as the acetone has done nothing] the green is still heavily present. What else can I do? Is this a lost cause?

"Even if the PVC has already permanently damaged the coin, everything you see as "green" should be removable [yes, in seconds WITH MS-70] (that's the "residue"), and until it's gone the damage will progress. It's been my general experience that the darker the green, the greater the need for worry, although the sheer square space occupied by the patch on the neck is obviously a concern." @SuperDave is correct.

Now, PLEeeeeessse put me back on ignore.

Fact: MS-70 removes green PVC from coins in seconds! Get some and try it full strength. BTW, I learned this in a COIN CONSERVATION SEMINAR. I've actually USED this product on thousands of coins so you CAN BELIEVE me.

PS: Loose the toothpick!

 

I'll try this acetone for a while longer and see what happens. If needed, I might get some diluted MS70 and see what happens.

Thanks for the input everybody!

 

These are the active ingredients in MS70 (the MSDS is freely available online; you can easily confirm this):

2-butoxyethanol
Potassium Hydroxide
Sodium Gluconate
sulfonated Sodium salts

Rather than dictate what's real, I'll leave it to the reader to determine what effect, if any, these things either alone or in combination can do to the phthalates used to soften PVC. I will say it seems like the Potassium Hydroxide should at least neutralize the hydrochloric acid formed by the interaction between PVC and silver, but I'm not completely sure of what the combination with the other ingredients in MS70 does to/for it.

 

The only real issue I have is that I've heard that MS70 is hard to work with, a split second too long and its ruined. Obviously that wont matter for this coin but for my 1904-O that's probably a 65 or so... I'd hate to ruin it.

 

Hmmmm. Maybe if you got a piece of cloth soaked with the cleaner and applied it to as specific of a spot as possible. (Maybe something other than cloth). this will allow you to use a more powerful cleaner, and apply it to a more specific area.

 

I do up to an 18 hour soak in pure acetone, followed by gentle use of a q-tip to get the tough areas.

 

Key point here: if you are going leave the coin in acetone for more than a few minutes, you must cover the container. I use a piece of SaranWrap, and it effectively seals the container. Acetone evaporates rapidly. Change the acetone twice a day, and use a qtip or two each time you change the acetone.

The other key point which Dave mentioned: some form of mechanical agitation of the affected areas is required. I recommend a Q-Tip, and I find it is more effective than a toothpick. *Very Gently* work the areas with the qtip to remove the green. Change the qtip each time, and change it when the head is green (that shows you it is working). When the qtip no longer gets green when you rub the area, you're done.