I luv you guys but I've never had a problem with labels or Sharpie markers or anything like that. Since no one can point to actual data or facts, I went to Andy McFadden's CDR Recordable FAQ website (http://www.cdrfaq.org/) for believable data. Here's what it said about this stuff:
Subject: [7-7] Is it okay to write on or stick a label on a disc?
(2004/02/22)
Only if you're careful. The wrong kind of ink or label can damage a disc. The adhesives on some labels can dissolve the protective lacquer coating if the adhesive is based on a solvent that the lacquer is susceptible to. Asymmetric labels can throw the disc out of balance, causing read problems, and labels not designed for CDs might bubble or peel off when subjected to long periods of heat inside a CD drive. So long as you use labels that were meant for CD-R discs, you will *probably* be okay.
For the same reasons, if you want to write directly onto the surface of a disc, you want to use pens that are approved for use on unlabeled CD-R media. The ink in some kinds of pens may damage the top coating of the disc.
Specific information can sometimes be found on the back of the jewel case that the discs come in. Old TDK CDR-74 discs had the following warning:
"[...]
2. Do not attach labels or protective sheets, or apply any coating fluids to the disc.
3. When writing titles and other information on the label (gold) side of the disc, these should be written in the printed area using an oil-based felt-tipped pen.
[...]"
Other brands say "use a permanent felt-tipped pen" or words to the effect that the ink shouldn't smudge. The most important part is to use a felt tip pen and not a ball-point, because the top layer of the disc will gouge easily on most media.
There are pens recommended specifically for writing on CD-Rs. Examples include the Dixon Ticonderoga "Redi Sharp Plus", the Sanford "Powermark", TDK "CD Writer", and Smart and Friendly "CD Speed Marker". Some of these are relabeled Staedtler Lumocolor transparency markers (#317-9), which are alcohol-based. Never use a solvent-based "permanent" marker on a CD-R -- it can eat through the lacquer coat and destroy the disc. Memorex sells water-based color "CD Markers" in four-packs (black, blue, red, green).
Many people have had no problems with the popular Sanford "Sharpie" pens, which are alcohol-based. Other people say they've damaged discs by writing on them with a Sharpie, though those discs may have been particularly susceptible. The official word from Sanford is:
"Sanford has used Sharpie Markers on CDs for years and we have never experienced a problem. We do not believe that the Sharpie ink can affect these CDs, however we have not performed any long-term laboratory testing to verify this. We have spoken to many major CD manufacturers about this issue. They use the Sharpie Markers on CDs internally as well, and do not believe that the Sharpie Ink will cause any harm to their products.
[...]
Sanford Consumer Affairs"
In any event, the Ultra Fine Sharpie pen looks almost sharp enough to scratch, so sticking with the Fine Point pen is recommended.
So long as you use the right kind of pen, it's okay to write directly on the top surface of the CD, label or no. Use a light touch -- you aren't filling out a form in triplicate. If the prospect makes you nervous, just write in the clear plastic area near the hub, or only use discs with a printable top surface.
Adding an adhesive label to a disc can make it look more "professional", but you have to be a little careful. If the label and the disc aren't a good match, the label can start to delaminate after a while. There are some indications that labels can shorten CD-R lifetime, so it might be best to label data archives and backups with a pen instead (see section (7-5) for more). Adhesive labels aren't recommended for discs you plan to keep for more than five years.
The best way to feel confident about labeling your discs is to try it yourself. Buy some labels, put them on some discs, leave them someplace warm, and see if they peel off. If they do, you'll need a different kind of media or a different kind of label. Some labels don't adhere very well unless they're attached to a disc with a plain lacquer surface on top, so combining labels with "inkjet printable surface" media may be asking for trouble. One note of caution: this only tells you if the label will peel up right away. It doesn't tell you if the label will still be nice and flat two or three years from now, especially if you live in the tropics where the air is always hot and damp. Using adhesive labels on discs meant for long-term storage may be unwise.
Whatever you do, don't try to peel a label off once it's on. You will almost certainly pull part of the recording layer off with the label. If you're going to label a disc, do it immediately, so you can make another copy if the label doesn't adhere smoothly. Any air bubbles in the label that can't be smoothed out immediately are going to cause trouble. Use a label applicator for best results.
It may not be a good idea to put labels on discs that will be fed into a "slot in" CD player, such as those popular in dashboard car CD players. Sometimes the added thickness will cause the disc to get stuck.
A number of companies make labels for CDs, and some sell complete kits including applicators and software. Two of the biggest are NEATO, at
http://www.neato.com/, and CD Stomper, at
http://www.labelcd.com/. Check section (8-3) for other sources. The software from
http://www.surething.com/ includes templates for a variety of different label layouts.
If you want a label that also covers up the clear plastic part at the center of the disc, search for "hub labels". There are even labels that *only* cover the hub section.
You can also buy printers that will write directly onto discs with a printable surface. One example is Primera Technology (http://www.primera.com/), which now handles the popular FARGO CD-R label printers.
Some information on CD-R labeling options can be found here:
http://www.cd-info.com/CDIC/Technology/CD-R/Labeling/ Sony's
http://www.sonydadc.com/ web site has a "Downloads & Templates" section with artwork that my prove useful. You can find most CD-related logos on the site (try
http://www.sonydadc.com/downloads/, scroll down to "Logos" for common formats). Some are also available from
http://www.licensing.philips.com/cdsystems/cdlogos.html. Mike Richter's CD-R primer has a very nice page on labeling discs. See
http://www.mrichter.com/cdr/primer/labels.htm. It is important to keep the CD balanced, or high-speed drives may have trouble reading the disc. According to one report, a disc that had a silk-screened image on the left side of a CD-R (leaving the right half of the disc blank) was unreadable on high-speed drives due to excessive wobbling. Most label kits come with a label-centering device, usually something trivial like a stick that's the same width as the hole in the middle of the CD.
Avery's CD-R labels became quietly unavailable in October 1997. The rumor is that the adhesive caused data corruption problems, so Avery recalled them. There are indications that the adhesive would fail on some discs and start to lift off within a short period of time. If you have Avery labels (#5824) purchased before this date, you should avoid using them. The labels being produced now don't have this problem.