Media Preservation - Preventing Disc Rot

TLDR: Disc rot can be caused by chemical reactions in the reflective layer, ultraviolet light damage, surface scratches exposing the delicate and corrosive layer to environmental factors, or deterioration of manufacturing materials. 

CD Disc Rot: Often times caused by oxidation of the reflective layer resulting in bronze discoloration or spotting. Although improper storage and mishandling can be a cause, it's typically due to chemical reactions in the reflective layer. 

DVD Disc Rot: DVDs have a protective layer over the reflective layer, making damage to the reflective layer less likely; however, it makes it more prone to delamination, a separation of layers that can look similar to a coffee stain. Can often be caused by poor case design. 

Both oxidation and delamination usually occur around the outer edge of the disc, typically due to adhesive not being cured properly and impurities during the manufacturing process. Disc rot along the inner edge is usually from poor case design or quality. ref: foam pins/disc holders

Tips for Preservation

• Touch only the outer edge and center hole to prevent fingerprints and debris. 
• Store discs in an upright position, similar to books, rather than flat down and/or in a stack. 
• Store in designated cases, not paper sleeves, to prevent scratching. Also return to cases immediately after use. 
• Remove debris with clean cotton or microfiber fabric. Wipe from the center to the edge, not in a circular motion! 

Here is my current physical film and series collection! I will certainly be reorganizing it soon. 

Sources

Andy Marken, Aug 2004. CD and DVD Longevity. How Long Will They Last?

Discogs. Protecting Physical Media: Combatting CD and DVD Disc Rot

LINKYOSMS, Oct 2013. Little Known Facts About Blank Media

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