Generally, it is best to keep ROM discs in a dry, cool environment. Other contaminates, however, such as inks, solvents, and pollutants, have the potential to irreversibly penetrate and to deform, discolor, or corrode the disc, causing permanent reading problems for the laser. The tests are generally performed by manufacturers, and the discs are usually categorized by the metal and dye types used in the disc.
These discs use gold, silver, or a silver alloy for the reflective layer instead of aluminum as in ROM discs. Gold will not corrode but is expensive. Silver is more reflective and cheaper than gold but is susceptible to corrosion if exposed to sulfur dioxide, an air pollutant that can penetrate the disc in the same way oxygen can-with moisture. Manufacturers use various silver alloys to help inhibit silver corrosion, and most R discs available today use a silver alloy reflective layer.
The chance of silver corrosion from exposure to sulfur dioxide is less than the chance of aluminum oxidation caused by high humidity. With proper storage, these discs will outlast the technology. R discs use a dye-based layer organic dye for recording data. The organic dye used in the data layer of R discs degrades naturally but slowly over time.
High temperatures and humidity will accelerate the process. Prolonged exposure to UV light can degrade the dye properties and eventually make the data unreadable. Heat buildup within the disc, caused by sunlight or close proximity to heated light sources, will also accelerate dye degradation.
Still, it would be prudent, in light of these claims, to purchase new discs as they are needed rather than to order large quantities and stockpile them for future use. RW and RAM discs are generally not considered for long-term or archival use, and life expectancy tests are seldom done for this medium.
Rewritable discs use a phase-changing metal alloy film for recording data and aluminum for the reflective layer. The alloy film is not as stable as the dye used in R discs because the material normally degrades at a faster rate; however, these discs should still be stable enough to outlast the current CD or DVD technology. The phase-changing film is affected primarily by heat, but ultraviolet UV light may also be a factor in the aging process.
The combination of high temperature and UV light may further accelerate the aging process. The combination of high temperatures and high relative humidity will also most likely accelerate the aging process, just as it does with the organic dye used in R discs. None are exposed to direct sunlight. My wife has CD's she keeps in her car all the time, in the console or glove box and none have deteriorated due to age.
Many are scratched and have fingerprints on them and all play well after being cleaned. The only CD's I have ever seen which won't play have had damage to the label side, cracked or holes through the playing area. AutomatedElectronics , Apr 28, Location: Mayor's Income, Tennessee.
I got it used so don't know about its history. It plays flawlessly on a very picky CD player so go figure. Other than that, my 30 year old discs are perfect. Location: It's one of the last things you need to worry about. Dave and timind like this. Location: Fonthill, Ontario. Dennis Metz , Apr 28, SandAndGlass , PhantomStranger , ti-triodes and 3 others like this. Location: Bay Area, U. The longevity of pressed discs is measured in hundreds of years.
Even archival CD-Rs have a life expectancy of up to years. Black Elk , Apr 28, Location: Merchantville NJ. BrewDrinkRepeat , Apr 28, Location: United States Of America. I see it as the pressed CDs will out last the players. They are here to stay. So far the pressed CD has proven itself in the long term.
Michael , Apr 28, Never had one fail. Michael likes this. Location: Suburban Chicago. If you look around the inner ring of a CD it should say who pressed the disc. These CDs went bad because the PDO plant used a bad or incorrect batch of materials to manufacture the discs during this period as I understand it. Compact Disc bronzing - Wikipedia, the free encyclopedia » In the classical world, these bronzed discs were fairly common on the Pearl label and Hyperion label during this period.
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