How can I remove the label from heat shrink tubing?
91% alcohol
It removes anything applied to a material, without damaging the surface of the material itself. (Acetone can &quot;smear&quot; some plastics, especially when you apply a lot of acetone at once.)
91% alcohol will remove printed inks, applied paints, etc., from hard surfaces.  I use it to remove unsightly logos, manufacturing marks, etc.
In fact, I remove Sharpie marker writing from almost any hard surface with 91% alcohol.
It also cleans off black smudge marks, greases, oils, foreign material, fingerprints, you name it.
I routinely run orange extension cables thru a rag I've wetted with 91% alcohol, to remove label gum, black marks, etc.  They look brand new.
You have two ways to use it:
If a surface can handle having all of the &quot;surface markings&quot; removed, I will spray it with 91% alchohol and cover it with a plastic bag, to help prevent evaporation.  Give it 5 mins and test.  It might need a 2nd go.
If a surface needs to have some surface marking remain (i.e.: a keyboard), I spray a rag fairly well with 91% alcohol and then wipe the surface.  A rag that's too wet to wiping too much will remove the paint on the keys, so test on the underside, first!
Don't bother using anything lower than 91%.  Lower percentage alcohol will be a waste of money for this.