Here is a recipe that allows you to remove seals, stamps and other notes from writing paper.To obtain this liquid, you need to take a 70% vinegar concentrate (about one teaspoon) and a small amount of potassium permanganate in crystalline form (at the tip of a knife). These substances are mixed, and after that the liquid is ready for use. Place a blank white sheet of paper under the piece of paper from which you want to remove something. Then take a brush (the softer and thinner her hair, the better for work) and, dipping it in the prepared solution, begin to draw this brush over the inscription until the inscription disappears. At this point, the paper will turn a brown tint, which must be removed with a piece of cotton dipped in a solution of hydrogen peroxide. Then a piece of paper moistened with a solution must be dried by ironing it with a warm iron. For this, soft matter is taken, a clean white sheet of paper is placed on it, and already on it is paper from which the inscription has just been removed. Then it is ironed (the surface of the iron must be clean).
Note: in this way it is desirable to remove labels only from thin sheets of paper. To remove inscriptions from thick sheets, it is more advisable to use a match instead of a brush, on the honed tip of which a small piece of cotton wool is wound (there are several such matches-brushes, because they quickly fail). Matches of the brush are moistened in the solution and, with careful reciprocating movements, over the inscription, remove it.
ANOTHER TWO RECIPES:
Recipe 1: take 10 g of oxalic acid, 10 g of citric acid, 100 ml of water. Stir it all. Wet the inscription with the resulting solution 2-3 times with a soft brush, then (also with a brush) moisten the inscription with water. After removal, dry the etched area with a blotter.
Recipe 2: take 10 g of hydrochloric acid, 10 g of sodium chloride, 30 ml of water. Stir all this and apply as the previous two means.