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CNN.com - CDs, DVDs not so immortal - May 6, 2004 <br />'A 11 • 11 <br />CDs, DVDs not so immortal <br />Page I of 3 <br />Powered by 10 Ck€ bili `y <br />(AP) -- Dan Koster was unpacking some of his more than 2,000 CDs after a move when he noticed <br />something strange. Some of the discs, which he always took good care of, wouldn't play properly. <br />Koster, a Web and graphic designer for Queens University of Charlotte, North Carolina, took one <br />that was skipping pretty badly and held it up to the light. <br />"I was kind of shocked to see a constellation of pinpricks, little points where the light was coming <br />through the aluminum layer," he says. <br />His collection was suffering from "CD rot," a gradual deterioration of the data - carrying layer. It's <br />not known for sure how common the blight is, but it's just one of a number of reasons that optical <br />discs, including DVDs, may be a lot less long -lived than first thought. <br />"We were all told that CDs were well -nigh indestructible when they were introduced in the mid <br />'80s," Koster says. "Companies used that in part to justify the higher price of CDs as well." <br />He went through his collection and found that 15 percent to 20 percent of the discs, most of <br />which were produced in the '80s, were "rotted" to some extent. <br />The rotting can be due to poor manufacturing, according to Jerry Hartke, who runs Media <br />Sciences Inc., a Marlborough, Massachusetts, laboratory that tests CDs. <br />The aluminum layer that reflects the light of the player's laser is separated from the CD label by a <br />thin layer of lacquer. If the manufacturer applied the lacquer improperly, air can penetrate to <br />oxidize the aluminum, eating it up much like iron rusts in air. <br />But in Hartke's view, it's more common that discs are rendered unreadable by poor handling by <br />the owner. <br />"If people treat these discs rather harshly, or stack them, or allow them to rub against each other, <br />this very fragile protective layer can be disturbed, allowing the atmosphere to interact with that <br />aluminum," he says. <br />Part of the problem is that most people believe that it's the clear underside of the CD that is <br />fragile, when in fact it's the side with the label. Scratches on the underside have to be fairly deep <br />http: / /cnn. technology .printthis.clickability. com /pt /cpt ?action =cpt &title= CNN.com + - +C... 5/6/2004 <br />