If the foam is adhering to the CD, the absolute BEST solvent to remove it is naphtha (what dry cleaners use.) It will not hurt the surface of the CD in any way. The easiest source for it is either Ronsonal or Scripto lighter fluid (ACE Hardware usually has Ronsonal).
Just dampen the foam, wait 30 sec. or so, and gently remove it. You can wash the CD afterwards with a mild solution of dish detergent, and rinse with dilute (50/50) white vinegar to get any detergent residue off.
DO NOT use products like Goo Gone! It will eat into the polycarbonate CD (and a lot of other plastics too; and polymer finishes like Varathane and spray lacquers). Naphtha is amazing stuff. You can use it, for instance, to clean vintage vacuum tubes, even the old Teles and Amperex with those fragile chalky labels, without fear of dissolving them (just wipe them gently with a tissue dampened with naphtha -- don't rub them, it's not necessary.) Whereas anything with just a HINT of water in it (even 90% alcohol) will take those labels right off!
I've been using it for years, and it has never ruined anything -- it simply softens adhesives, even old adhesive, like UPS labels you want to get off a box so you can reuse it. It's also great for cleaning. Especially cleaning surfaces just before you are going to apply anything with a self-adhesive backing.
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Just dampen the foam, wait 30 sec. or so, and gently remove it. You can wash the CD afterwards with a mild solution of dish detergent, and rinse with dilute (50/50) white vinegar to get any detergent residue off.
DO NOT use products like Goo Gone! It will eat into the polycarbonate CD (and a lot of other plastics too; and polymer finishes like Varathane and spray lacquers). Naphtha is amazing stuff. You can use it, for instance, to clean vintage vacuum tubes, even the old Teles and Amperex with those fragile chalky labels, without fear of dissolving them (just wipe them gently with a tissue dampened with naphtha -- don't rub them, it's not necessary.) Whereas anything with just a HINT of water in it (even 90% alcohol) will take those labels right off!
I've been using it for years, and it has never ruined anything -- it simply softens adhesives, even old adhesive, like UPS labels you want to get off a box so you can reuse it. It's also great for cleaning. Especially cleaning surfaces just before you are going to apply anything with a self-adhesive backing.
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