Sony PCG-SR33K - Manual (Page 27)

anti-static spray, as they may cause damage to the disc.
 For normal cleaning, hold the disc by its edge and use a soft cloth to wipe the surface from the center out.
 If the disc is badly soiled, moisten a soft cloth with water, wring it out well, and use it to wipe the surface of
the disc from the center out. Wipe off any remaining moisture with a dry, soft cloth.
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