Oh noes teh sky is falling!

[Vilya]

Originally Posted by slimjean

Congrats I guess this gives license to say I am a pretender now that I choose to stay private? According to your fan it does.

Telling us what degree you have, and in what field of study, did not violate your privacy.

Originally Posted by slimjean

We could play the stupid game of who has been in the most labs, who has done the most experiments, who has worked with the most doctors, but what is the point?

"We" could also provide citations that support our statements. Everyone here has but you.

Originally Posted by Vilya

Additionally, a number of plastics dealers recommend a product called "Novus #1" to clean polycarbonate plastic. Here's one example:

"For proper cleaning and care of your polycarbonate sheets, we recommend Novus #1 cleaner and a soft cloth."

https://www.acplasticsinc.com/inform...-cleaning-care



Guess what Novus 1 cleaner contains as the cleaning agent? That's right: isopropyl alcohol.

[Show spoiler]Attachment 275539

https://www.webstaurantstore.com/doc..._448pn7020.pdf

[bhampton]

I think you are both fine folk who just don't agree with how to clean discs.

Maybe we should all go digital, ... you can't clean a digital copy .... ?

[Vilya]

Originally Posted by slimjean

I HAVE TOLD YOU THAT I WANT MY PRIVACY.

What is it that you don't get? If I mention job one and university one you know exactly where I live and exactly the place I work at because there is only ONE facility.

There is SIX people in my department so now you got it nailed to the exact location in the world.

You are in the army. There is no way to know who you are and if they did you are one of how many candidates over how many years??

Quit acting like a stalker. Respect my wishes.

P.S. I told you my degree. It is a B.S. Chemistry.

I never asked about your job.

I asked what degree do you have, in what field, and from which university. You *finally* answered the first two parts of that question and nothing that was asked, or reluctantly revealed, has threatened your privacy.

I shared some of my training and where I received it. None of which helps anyone to locate me...unless they have a time machine. Oh wait, I never said when I was there. Guess I'm still as anonymous as ever.

What I would really like to see are citations from credible sources (that are not scared of their own shadow) that refute the citations that I provided. Scientists are supposed to provide evidence. Where's yours?

[Vilya]

Originally Posted by slimjean

Ok but I just got to say this, the Novus cleaner above contains less than or equal to .5% Isopropanol!!

So this is the big reveal???

I state that over the counter 70% is not a good idea and this is the best that he comes up with?

Talk about scouring anything to be right.

Yeah I know what I am dealing with now.

It remains the active ingredient. How much of it that is found in Novus 1 does not change the excellent polycarbonate-isopropyl compatibility rating contained in the chart at this web link:

https://www.calpaclab.com/polycarbon...ibility-chart/

Nor does it undermine the practical experience of using medical grade isopropyl alcohol at 99%+, consumer grade at 91%, or even 70% to clean otherwise unsalvageable discs.

I, and others, have used isopropyl alcohol for decades to clean discs that do not respond to soap and water alone. A few seconds of direct application of isopropyl alcohol, then a quick rinse with water finally followed by drying with a clean microfiber cloth has saved many an otherwise unplayable disc.

You would just have everyone give up hope and discard the disc.

[Wendell R. Breland]

Originally Posted by slimjean

First of all, I appreciate you having a civilized discussion. We can disagree without it turning into personal attacks.

On any forum there are many pretenders and a few genuine knowledgeable people. Some of us just want to know which we are dealing with.

Also the coatings on optical discs are also dubious.

A blanket statement like that I just not get. What specifically is “dubious” about the hard coat?

If you have a flawed disc, pouring any solvent on an organic surface is not a good idea. It is chemically true.

If you have a flawed disc it most likely will not play anyway.

From my view point all Vilya asked for was verification and you did ignore or side stepped his request.

IMO, I believe most readers here are interested only in short post, a step 1, 2, 3 process that is backed up with verifiable facts like these.

[Vilya]

Originally Posted by slimjean

Study the structure.

https://en.m.wikipedia.org/wiki/Polycarbonate

Read the charts included with the article.

Your own link above shows that polycarbonate has a chemical resistance to alcohols in general (type of alcohol is not specified), that is good.

This link shows that when you specify isopropyl alcohol the compatibility with polycarbonate is excellent as I have consistently maintained.

https://www.calpaclab.com/polycarbon...ibility-chart/

[Wendell R. Breland]

In the days of LD there were problems with warped disc. I ordered 2 pieces 12 x 12 x .5 inch glass for the purpose of flattening the disc. The process worked better if the disc were warm when placed between the glass. On one occasion I placed a disc in a warm oven but forgot about it till sometime later. When I did check the disc it drooped way down and was beyond any hope.

So I can say from my own experience placing a LD supported only in the middle in a very warm oven for to long will warp the disc very badly. Anyone with LD should be able to verify this.

[Wendell R. Breland]

So should I be worried that my plastic containers that say “Safe for gasoline” is going to suddenly melt? Had two for 11 years, 1 has had fuel (gas oil mix) in it for those 11 years. refilled about every 2 months.

[Vilya]

Originally Posted by slimjean

Having a chemical say "good" does not prove real world examples.

It's your citation and it is consistent with the one that I provided from the outset of your obstinance.

Those of us that have been using various concentrations of isopropyl alcohol to clean discs that do not respond to soap and water have related decades of "real world" examples from our own experiences that demonstrate that isopropyl alcohol is perfectly safe to use to clean a polycarbonate optical disc as has been exhaustively described.

Polycarbonate has excellent compatibility with isopropyl alcohol, period. All of the articles presented in this interminable discussion confirm this fact and it is consistent with our own experiences using it to clean discs that do not respond to soap and water alone.

Originally Posted by slimjean

This idiotic idea that I am saying throw away a disc is absurd.

You may as well say as much as you offered no alternative cleaning method for a disc that does respond to soap and water. In the absence of such an alternative, that can only mean discard or replace the disc.

Originally Posted by slimjean

If you care about your media stay away from alcohols on plastic. Wtf!!

You set the tone of this entire interminable discussion right there. I, and others, offered a cleaning solution, isopropyl alcohol, that works where soap and water have failed. You offered nothing helpful at any step along the way. Just live with an unplayable disc. What great advice from The Reluctant Chemist. Nothing that you have posted here helps anyone to fix a disc that does not respond to mere soap and water.

[Vilya]

Originally Posted by Wendell R. Breland

In the days of LD there were problems with warped disc. I ordered 2 pieces 12 x 12 x .5 inch glass for the purpose of flattening the disc. The process worked better if the disc were warm when placed between the glass. On one occasion I placed a disc in a warm oven but forgot about it till sometime later. When I did check the disc it drooped way down and was beyond any hope.

So I can say from my own experience placing a LD supported only in the middle in a very warm oven for to long will warp the disc very badly. Anyone with LD should be able to verify this.

May I have your recipe for Baked Laserdisc? It sounds tasty!

[Vilya]

Originally Posted by bhampton

I think you are both fine folk who just don't agree with how to clean discs.

Maybe we should all go digital, ... you can't clean a digital copy .... ?

But you can clean the modem and router!

You are being very charitable to a pair of stubborn jackasses.

[Show spoiler]Blessed are the peacemakers....

[Wendell R. Breland]

Originally Posted by Vilya

Polycarbonate has excellent compatibility with isopropyl alcohol, period.

IMHO, if the poster had stated up front their training and credentials, some facts with citations about isopropyl alcohol and the short term effects, if any, on polycarbonate (CD, DVD and HD DVD), provided alternate cleaning then we would not have this friction.

Next would be the cleaning of Blu-ray disc with a Acrylic resin coating. This site includes 50% isopropyl alcohol as one of the recommended solutions.

[Anthony P]

Originally Posted by Wendell R. Breland

For me, a recap of disc cleaning:

• Use a mild soap and water
• Use isopropyl alcohol as an alternate (I use 99.9%)
• Dry with a clean microfiber cloth (I also use Bounty paper towels but they can leave residue requiring a re-cleaning)
• Use compressed air for light dust particles (I use one of these). I would not blow on a disc from my mouth.

Do not use lacquer thinner, acetone, nail polish remover, products with ammonia (Windex)

I have never used alcohol. If I ever need to I will have to give it a try.


IMHO I will just add to your first point to use dish soap.
1) it is a great degreaser (needs to clean those nasty pots)
2) they are formulated not to leave a film (glasses need to look good).
3) some hand soaps can be "gritty" (not like your hands will be damaged by a bit of grittiness) while dish soaps are mild

[Anthony P]

I have never tried rubbing alcohol and maybe it is the best thing (not questioning that).

But I do feel this conversation has gone off field a bit. When discussing DVD/CD discussing polycarbonate made 100% sense because except for the data layer(and it should not come in contact with the cleaning product) it is 100% polycarbonate, but BD/UHDB has a hard coating on the data side and the cleaner is actually used on the hard coating.

[Vilya]

Originally Posted by Anthony P

I have never tried rubbing alcohol and maybe it is the best thing (not questioning that).

But I do feel this conversation has gone off field a bit. When discussing DVD/CD discussing polycarbonate made 100% sense because except for the data layer(and it should not come in contact with the cleaning product) it is 100% polycarbonate, but BD/UHDB has a hard coating on the data side and the cleaner is actually used on the hard coating.

I only use alcohol when other cleaning methods have failed.

I have seldom had to use it on a blu-ray disc as soap and water is usually sufficient to remove that greasy ooze that some cases transfer to the blu-ray disc.

Even in the rare instances where I did use alcohol to clean a blu-ray disc, it never harmed the hardcoat or the disc. Again, using alcohol is the cleaning method of last resort, the exposure to alcohol is mere seconds, and the disc is then thoroughly rinsed and dried. Alcohol often works where soap and water fail.

[Wendell R. Breland]

Below is a drawing that I did in 2006 of 1 and 2 layer Blu-ray disc.

Size appreciation: Take out your metric ruler and look at the mm scale, 1000 μm’s fit in the space of 1mm.

[Show spoiler]

[slimjean]

Originally Posted by Anthony P

I have never tried rubbing alcohol and maybe it is the best thing (not questioning that).

But I do feel this conversation has gone off field a bit. When discussing DVD/CD discussing polycarbonate made 100% sense because except for the data layer(and it should not come in contact with the cleaning product) it is 100% polycarbonate, but BD/UHDB has a hard coating on the data side and the cleaner is actually used on the hard coating.

My issue has always been with the coating as I said repeatedly.

Any flaw can and does trap moisture and over time that can cause problems with dehydration even with a low percent alcohol as it evaporates and takes atoms with it.

My issue was repeated use. Over the counter alcohol is not reliable and can also contain methanol. Obviously when one brings up a specially formulated solution that is .5% alcohol that is a completely different story.

From my experience isopropanol breaks down polycarbonate quickly. My criticism was using it as a washing method and it being insanity to trust it on media you care about. Even as a last resort I cannot agree with it.

I have worked with millions of polycarbonate containers and as jacked up as it is, depending on the manufacturing the damage has been instant. Now I admit that there were some less than ideal bottles and maybe there were other factors, but crazing is real and that is because of the non-uniform way that polymers are formulated. This for small example came from being on three government projects with stability studies (which no I am not sharing).

Blurays are often not to the highest standards.

Hell my criticism is still against using the alcohol at all.

The Novus active ingredients are clearly silica based polymer polishing angents which also have methyl carbon bonds.

In short the design is to move the foreign material away through lubrication much like soap does with surrounding with long carbon chains.

In all this debating this obvious fact has been ignored. Isopropanol takes away grime by breaking up petroleum chains (grease). Of course this polarizing process is what breaks down polymer chains which is the makeup of the disc and its coating which both are prone to flaws. Think about it, alcohol breaks down all kinds of organics very effectively. Of course it is like feeding your dog stuff through their water to clean their teeth...ever think what that does to kidneys? The thing thst cleans can turn against you as well.

Two different mechanism. Soap polarizes but keeps molecules intact (for the most part). Alcohol by design breaks bonds.

This is coming from experience as a chemical scientist with 40+ years in industry. Believe my credentials or not, but the information is not hard to find.

The links I provided also said that Isopropanol has good compatibility with polycarbonate. That is a theoretical with pure alcohol/water (not methanol) and a perfectly formulated substrate while having perfect cleaning conditions that are free of acids that can and will be catalysts to more reactions.

Yeah a little bit here and there might not be too bad...or you start creating damage to a disc you dkn't even know about and if it is a favorite might you get grime again?

To each his own because the last thing I want is another attack on my career or knowledge. All I can say is research more than (this is Good...this is "compatible"..this expert said this with no vested interest).

I have seen it too many times. Chemically "resistent" containers break down quickly. Despite being advertised one way, organic solvents with polymers of any kind are not wise unless there is a special formulation like Novus that has miniscule amount (hell the silica no doubt acts as a coating to repel that anyway!).

For me having 4000+ optical discs and being a movie collector since the 70's with laserdisc and video (like many of us here), I stay away from organic solvents if I can help it. Head units...sure.

Now at times I will take off that gummy crap on a bluray case but I still wash it with water and dry it and let it evaporate. If the solvent takes off some ink or even a layer on the covering...big whoop. I am not playing or trying to recondition a movie disc!

To each his own, that is my take and I don't need a huge study to have an informed opinion. It is up to the reader to do the research to fact find for educated free advice.

[Vilya]

If a disc remains unplayable after using soap and water to clean it, logic alone dictates that you have nothing to lose by trying alcohol...or anything else for that matter.

I would not use, nor recommend, any cleaning method that proved harmful to the movie/TV show library that I have spent decades building. All I need is my own experience to have an informed opinion.

[slimjean]

Originally Posted by Vilya

If a disc remains unplayable after using soap and water to clean it, logic alone dictates that you have nothing to lose by trying alcohol...or anything else for that matter.

And I say for the reasons I have outlined, use another method.

I don't agree you have nothing to lose. You could lose that disc.

There are so many different kinds of soaps, and if you do the research, none of them will be harmful like alcohol that can break apart bonds.

I understand that you are using it as a last method. I actually stated that. However, when it comes to removing grime which are often oil based, soap actually outperforms alcohol IF it is the right kind of soap.

There is no question that if you want to break apart bonds, as I stated in what I wrote, then yes alcohol can do that, but again, it also can go a step farther and continue to break bonds on the poly plastic.

You believe alcohol is the safety net, I have described why it can be detrimental. Ultimately others will have to decide if my advice makes scientific sense or not.

I could spray goo gone on my discs and get tons of stuff off. That doesn't make it is a good choice! Nine times out of ten if I am quick, my disc my still play fine, but it is a risk without question (not to mention a risk to your hands with exposing yourself to a toxin that can and will make free radicals in your body).

p.s. On a side note, I have never used alcohol on my discs and I have literally only had a couple that were unplayable and that was likely from a deep scratch or a manufacturer error. I repeat NEVER. A small amount of soap gets almost everything off because of the design.

Who washes their hands with alcohol? But yet the industry for getting dirt of your hands is almost universally soap (just many of them can take longer).

At some of my jobs I have seen people wash their hands off with Methyl Ethyl Keytone. Sure it is effective, but idiotic all the same. I am not putting that crap on my hands! A simply organic class will tell you how dangerous that can actually be for your health for many similar reasons that I am stating now.

[Anthony P]

Originally Posted by slimjean

Who washes their hands with alcohol?

maybe I am misunderstanding your point, but you do realize all the hand sanitizers everywhere, that probably almost everyone has used in huge quantities these last couple of years, are alcohol based.