To remove fingerprints or dusts off optical discs, the best way is to use a microfiber cloth and wipe from center out to the edges. Do not rub back and forth or wipe in a circular motion.
To remove liquids such as coffee or ketchup, you can rinse the discs with water first. Avoid using alcohol or chemical cleaners which may leave residue and potentially damage the surface of discs. Once the disc is clean, wipe the discs with the same motion from center out to the edges and set the disc to dry in an environment without direct light or sunlight. Let the surface dry for at least 24 hours.
*Disclaimer: The above directions are for reference only. The surface of discs sometimes may have already been damaged and become unreadable even after cleaning. Please practice above method at your own risk.
It’s ideal to back up your disc collection to prevent accidental data loss. Nimbie Standalone can easily duplicate multiple master CDs with a press of button.