How to clean sponge markings?

[xiaopv]

Some of my discs have a sponge marking problem. Early released box sets usually have a square sponge between two discs. (I guess that is to protect discs) But because of moist and temperature, sponges resolve, go bad and leave a serious marking on discs. I tried to use some mild hand soap and cotton ball, I don't think they are doing anything unless I tried hard which will leave scratches and eventually damage the disc. Anyone have the same experience before? Any idea how to clean it?

[SONNET CLV]

I don't know off hand about cleaning such a "spotting", but I did hear some years ago that the spongy protective materials in these CDs was due to degenerate and could possibly harm the discs if stored with them long enough. The article I read (possibly in STEREOPHILE) suggested getting rid of the sponge stuff. That's generally what I've done. But ... I haven't noticed any damage on discs that still have the sponge after several years. (I still run across some of these occasionally in my collection.)

--SONNET CLV--

[Imperfect Pitch]

xiaopv - I don't have a direct answer for you, only a related suggestion ... you could make backup copies of the CDs and use those from now on. That way, you won't have to worry about the originals deteriorating over time. Of course, this assumes the sponge markings aren't so bad that they prevent you from making copies. Oh, and remember to keep the originals around (pesky copyright laws).

[Beckmesser]

I have a question related to the durability of CDs.

I have a book-like carrying case, each page of which has four pockets into which I slip my CDs. I leave the case in the car year-around so that I have something to listen to when driving. I am wondering if the discs will eventually deteriorate from being stored in a hot car (not in direct sunlight). They still sound fine to me.

[Chalkperson]

The sponge does harden and eventually decompose but surely this only affects the label side which is the side that comes into contact with the sponge...

[Imperfect Pitch]

Beckmesser - See my earlier suggestion to the original poster; might be relevant to you as well. I don't know if cars get hot enough to damage CD's, but sliding them in and out of those sleeves could scratch the discs and cause them to skip in extreme cases (has happened to me).

[xiaopv]

Chalkperson: I remember reading some posts somewhere saying that it is more important to protect the label side than the playing side since that is where the information stored.

Xiao

[Chalkperson]

Chalkperson: I remember reading some posts somewhere saying that it is more important to protect the label side than the playing side since that is where the information stored.

Xiao

OK, yes, come to think about you are indeed correct, I forgot that they were burned from above...

[Gary]

This article is taken from BBC Music Magazine's April 1994 issue. I typed this, so there may be typos.

Perfect sound for ever?
The recent reports on CDs’ durability—or lack of it—have caused a great stir among record buyers, reports Barry Fox. But are we still the victims of a cover-up?

Recent shock-horror stories about self-destructing CDs have understandably scared the life out of record collectors. When Philips launched the CD system in 1983, it used the slogan ‘perfect sound for ever’. This was quickly dropped, as hi-fi buffs complained about the sound of early recordings and players, while rumours spread that the discs would degenerate with age.

The first proof that CDs would not last forever came in 1988. Some pressing plants discovered that the inks they were using to print label information direct onto the disc could eat through the protective coating and destroy the very thin layer of shiny metal which reflects the laser light, stopping the discs from playing.

Of all the CD pressing plants, only Nimbus would admit to the problem. Other pressing plants, and the record companies, wanted to sweep the risks under the carpet. They pilloried the press, too, for exaggerating the problem. But because the dirt was dished publicly, the record industry had to find out what was wrong and put it right. If pressing plants had been able to continue secretly cutting corners, a huge number of discs would now be degrading. The recent discoveries involve quirks of proprietary manufacture and almost certainly affect only small numbers of discs. How many? No one can tell. But here are the known facts.

Last year, after an article in Time Out, Philips’s PDO plant in Blackburn, Lancashire, admitted that some CD singles (5-inc CDs with up to 20 minutes of music), which had been pressed in the late Eighties for record companies Polygram and A&M, were failing.

It is important to know that Philips built the Blackburn plant 15 years ago to press 12-inch video discs. Demand was small, so PDO began pressing 5-inch CDs. The factory uses a wet chemical process, similar to that used for making mirrors, to deposit a layer of silver as the reflective surface. Most CD pressing plants deposit aluminium as vapour, but the necessary equipment was not available when the Balckburn plant was built.

Around 1988, when the record companies started to release CD singles, they cut costs by using cardboard sleeves instead of plastic jewel cases. In late 1989, PDO found that some discs in board sleeves were refusing to play after a few months’ use. Analysis of the sleeves showed that some were made from high-quality processed paper, and did not affect discs. Others were made form virtually untreated wood pulp which was releasing sulphur which diffused through the protective lacquer on the label surface of the CD, reached the silver layer and tarnished it. So, sooner or later, the CD player is no longer able to read the disc.

Last year Polygram said it was confident that the problem special to PDO at Blackburn, because silver is more susceptible to sulphur than aluminium. But PDO said it believed aluminium would degrade in exactly the same way if the record companies had supplied card which had a high sulphur content. As soon as PDO recognised the problem it started checking all paper and card. But what about the plants? What about full-length CDs that are packaged in cardboard boxes, as is now routine in the USA? And what happens if the paper inlay notes which sit inside a jewel case are printed on poor quality paper?

When I asked several record companies these questions, I was shocked by their ignorance and lack of interest. It soon became clear that the security of our record collections depends on the diligence of the pressing plants, not the concern of the record companies. The good news is that last year’s scare has driven responsible plants into checking all paper and card for sulphur.

The bad news is that some cut-price plants may not be checking their card and paper. Also PDO has now found that some plastic jewel cases can also release sulphur. This has caused the failure of some full-length CDs pressed at Balckburn. But PDO is confident that this is something unique to Blackburn, and can affect only a few CDs.

Blackburn’s original video disc process covered the silver with a nitro-cellulose lacquer, applied in a solvent which was evaporated in hot air. When PDO stated pressing CDs, the same lacquer was used. It started switching the plant to the use of the more modern acrylic lacquer early in 1993. This blocks high levels of sulphur, even in hot conditions. So this should mean there are no more nasty surprises in store.

Philips has now set up a free helpline for anyone concerned about their CDs (0800 387063). The company asks people to check their discs for manufacturing origin before phoning PDO direct. Those made at Blackburn carry the mark ‘Made in the UK by PDO’ near the center. Philips also advises that even perfect discs from PDO may look slightly yellow, because of the natural colour of the nitro-cellulose lacquer. No one noticed this until the scare over tarnishing, which causes a much darker bronzing.

For me there remains one nagging doubt. Philips and PDO have been remarkably frank and honest about the sulphur problem and the steps taken to solve it. Other pressing plants I contacted either ducked the issue, failed to return my calls or showed worrying ignorance or lack of concern. There may be some pressing plants around the world crossing their fingers, hoping that other, perhaps more serious, pressing problems secrets do not come home to roost.

[Brendan]

Good CD cleaning units are available online or through good Hi-fi stores. I can't recall which cd cleaning spray I use, but a good quality one used with a lint-free cloth should do the trick.

Scoth CD Cleaning cloths retail for about $5 for a pack. A CD washing unit costs from $10, ultrasonic units (probably not what you are looking for here) from about $45.

[DavidRoss]

We just had a discussion about this on GMG--the solution our distraught poster found worked for him was to soak the discs in distilled water, then the foam bits came off easily with gentle cleaning (soft, moist cloth, wiping radially only, please, from center hole to circumference).

[xiaopv]

We just had a discussion about this on GMG--the solution our distraught poster found worked for him was to soak the discs in distilled water, then the foam bits came off easily with gentle cleaning (soft, moist cloth, wiping radially only, please, from center hole to circumference).

Thanks for the suggestion. I believe that I have rinsed the disc for long enough time but nothing has come off. Do you think immerse it in the water for a while will do the work?

Thanks,

Xiao