# WTF happend to my DVD?
**URL:** https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673
**Category:** Factual Questions
**Created:** [November 20, 2008, 5:44pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673 "2008-11-20T17:44:32Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@Zerc](https://boards.straightdope.com/u/Zerc)
#### Post date: [November 20, 2008, 5:44pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/1 "2008-11-20T17:44:32Z")
After hearing of a friend’s woes I had a look at my BBC Life on Earth DVDs which I have never watched before. 2 of the 4 DVDs had a strange pattern on the data side which I have never seen before, it’s almost like a floral pattern. My friend tried to clean his without much luck but I tried toothpaste which fortunately worked. Anybody got any ideas what could have caused this?
A scan of the full CD - [http://img84.imageshack.us/img84/4216/cd1lc6.jpg](http://img84.imageshack.us/img84/4216/cd1lc6.jpg)
A close up -[http://img510.imageshack.us/img510/5056/cd2qo6.jpg](http://img510.imageshack.us/img510/5056/cd2qo6.jpg)
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### Author:  [@beowulff](https://boards.straightdope.com/u/beowulff)
#### Post date: [November 20, 2008, 5:53pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/2 "2008-11-20T17:53:49Z")
How were they stored? I notice that there is an area around the edge which seems to be free of the alien infestation.
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### Author:  [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)
#### Post date: [November 20, 2008, 5:59pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/3 "2008-11-20T17:59:09Z")
Whatever it certainly isn’t normal. Maybe that was meant for the other side and they were loaded wrong for the process.
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### Author:  [@scribeben](https://boards.straightdope.com/u/scribeben)
#### Post date: [November 20, 2008, 6:01pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/4 "2008-11-20T18:01:26Z")
I doubt this is the cause but it is possible to etch the data side of a DVD. However that pattern covers the entire disk and according to the site below, you can only etch an area that hasn’t been written.
> [@](#):
>
> You can also burn images on to the data side of any standard disc, in an area not already written with data.
[http://www.pcpro.co.uk/news/81037/nec-adds-etching-to-dvd-burners.html](http://www.pcpro.co.uk/news/81037/nec-adds-etching-to-dvd-burners.html)
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### Author:  [@Fritz](https://boards.straightdope.com/u/Fritz)
#### Post date: [November 20, 2008, 6:43pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/5 "2008-11-20T18:43:50Z")
It may be a “Hardcoat” product that has gone bad. It’s spun on during disc manufacture to protect the read-side from scratches. Does it flake off or can you feel the pattern?
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### Author:  [@Nanoda](https://boards.straightdope.com/u/Nanoda)
#### Post date: [November 20, 2008, 7:00pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/6 "2008-11-20T19:00:03Z")
Wow. Long-term thermal stress? I’ve had the aluminium flake off of pressed CDs when I stored them against each other or against certain types of plastic, and I have an early burned CDr where the ink ‘bled’ after being kept in my car all winter (I imagine it froze). I haven’t seen that particular mode of failure before though. It looks like the problem is with the plastic substrate, rather than the data layer.
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### Author:  [@Zerc](https://boards.straightdope.com/u/Zerc)
#### Post date: [November 20, 2008, 7:07pm UTC](https://boards.straightdope.com/t/wtf-happend-to-my-dvd/473673/7 "2008-11-20T19:07:39Z")
The DVD seems to work fine now after I cleaned them with toothpaste so it doesn’t appear to be anything permanent. I thought at first that the DVDs had come loose during shipping but I don’t see how that would have caused these particular marks.
The marks definitely didn’t flake off and the surface didn’t feel obviously different.