Take a piece of packing tape/scotch tape/strapping tape and stick it to the residue on the top loader and pull the tape off. Do this till the residue come off and then throw the piece of tape off with the residue.
I do not use any alcohol or stuff like that. I am afriad a little will be left on the top loader and it could cause damage, so what I do peel off all the tape as much as I can, then use my finger and rub the tape residue off as much as I can, then take an old sock, and the ridges wipe the rest off. makes for a sore hand/wrist, but it avoids using any type of chemical.