Removal of ink stains on wood is dependant on wood treatment
How to remove ink stains on untreated wood
Rub the ink stain with a toothbrush dipped in lemon juice.
How to remove ink stains on polished wood
Dab the stain with a cloth soaked in surgical spirit or sand lightly with very fine sandpaper.
Then buff & polish.
Removal of ink stains on varnished wood
Wipe as much of the stain off as you can and dab the varnished wood with a cloth soaked in a solution of one tablespoon of olive oil, a tablespoon of methylated spirits and a spoonful of turpentine.
Buff the wood with silk cloth.
But if the stain has penetrated the varnish, the only way to remove the stain is to remove the varnish from the wood.