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The Black Keys The group released an album on drives that change color after use
At room temperature, the disk with the album Brothers just black, without any inscriptions. But in fact, it is covered with a thin layer of thermochromic material that changes the color black to white when heated.
Inside, a CD player, heated, becomes a cream color, and it appears the album title and other text. When the disc cools, it becomes black again.
via factroom.ru