Methods used to remove labels and their adhesives should be appropriate to the surface. You can be somewhat aggressive with the food label on a plain glass jar, for example, but anything with more value – such as an object with a painted-on design – requires kinder, gentler treatment.
If this doesn’t work, try the following: If the object has a painted design on it, test with rubbing alcohol in an inconspicuous place first because alcohol dissolves inks and some paints. If it passes the test, saturate a fresh cloth or paper towel with rubbing alcohol and place it over the label or adhesive for a few minutes. Do this in a well-ventilated area, since alcohol is both volatile and flammable. Once fully saturated, any remaining label scraps or adhesive can be rubbed off gently with the alcohol-soaked fabric. Wash the object in liquid dishwashing detergent, rinse, and dry.
You may try using nail-polish remover for really stubborn labels or adhesives (test first in an inconspicuous place to be sure it won't harm the underlying surface), but the acetone it contains will dissolve paint quickly. It’s also harsh on skin and flammable, so wear protective gloves and work in a well-ventilated area. Put a few drops of acetone on a fresh cloth or paper towel and gently rub at the label adhesive until it’s gone. Wash the object in dishwashing detergent, rinse well, and dry.
If you use these methods progressively, wash and rinse at the end of each step to avoid mixing the chemicals you are using in the removal process.
Reference:
Jeff Bredenberg, editor, in Clean It Fast, Clean It Right: The Ultimate Guide to Making Everything You Own Sparkle & Shine.