Why the color of CD is different from other discs?
The colors of a disc are usually determined by the dye layer (recording layer) and the reflection layer:
There are three dyes: one is Cyanine, blue color, made by Taiyo Yuden; another is Phthalocyanine, transparent with a slight shade of yellow, made by Mitsui Toatsu Chemicals; and the other is Azo, blue color , made by Mitsubishi
The colors of reflection layer are usually gold or silver. Therefore:
Dye Color + Reflective Layer => Final Color
Cyanine + Gold => Green
Cyanine+ Silver => Ocean blue
Phthalocyanine + Gold => Gold
Phthalocyanine+ Silver => Platinum
Azo + Silver => Blue
Adjustments in the ratios of dyes used can also cause the shades of color to vary.
