I want to record something on a CD. I put it in the drive. I record the content on to it. I pop the CD drive, carefully lift it out, remembering to “handle this sound carrier unit as I would an LP”…and now I’m ready to mark it.
So, which side do I write on? And is any kind of marker OK?
Write on the side that’s up.
Use a sharpie, not a pointed instrument.
Do not use a cheap sharpie or felt tip. Some of them contain acidic inks that will eat holes in the aluminum coating on a CD. I found it annoying when the aluminum in the centers of the A’s on one of my CD’s fell out after a year. I now use a brand name felt tip or sharpie, and have not had the problem repeat.
Thanks for your help.
I just love this place! You can ask anything–anything!– and get an answer within an hour.
CORRECTION: Recordable CD’s do NOT have an aluminum coating, the recordable coating is laser sensitive, and has another protective coating on top of it.
Commercially mass produced CD’s have the encoded information pressed in the plastic which is then coated with Al. in vacuo.
Squink is right on the brand name felt tip sharpie. (Keep it capped when not in use for longer writing life.)
As you say, the recordable coating on these CD’s is a photosensitive dye. However, that dye layer is covered with an aluminum or thin metal layer. If your ink eats thru that layer, the disk becomes much less reflective, the dye layer is exposed, and is quite easily smudged.
Why not write on it first, and then record the data? I mean, it works either way, but you might find that easier.
Thought I’d mention that you can get bulk CDs that have no printing on the top side. They may look nearly identical on both sides. The only way to tell which is the top is by the number stamped into the inner ring. When it reads forwards, that’s the top.
AFAIK you have to get these utterly blank disks if you want to put them in a CD printer.
Another way is to feel for a ridge surrounding the center hole - this ridge is the “stacking ring”, and is the bottom, or read side of the disc.
The metal most commonly used for CDRs is pure silver or silver alloy.
Another sure sign is if you put the disk in and it tells you there is no disk.
Take it out and turn it over.
I have a variety of recordable CD’s. They come:
a. totally transparent with a protective lacquer or similar protective coating over the photo/laser senstitive coating,
b. a white protective coating with red over print,
c. a variety of colors of what appears to be vacuum coated aluminum and lacquer. (NO it is NOT Silver.)
d. an unidentifiable colored coating over the reactive encoding layer.
Construction of CD-RW differs from CD-R. Here’s a link that details the construction of both:
http://www.osta.org/technology/cdqa15.htm