A Sheet of Paper In addition, out of the concept krautfarben handmade papers were created from shredded red cabbage leaves. In production studies various approaches are presented, in which the mixture with other pulps exhibits a wide range of colour and consistency. The paper is completely compostable and could provide a way to recycle vegetable scraps that are no longer suitable for other purposes. The purple papers can then be changed in colour with transparent liquids acid and base. Geometric graphics form the screen print pattern as they face the irregular paper structure. Base was printed as a square shape, which stains the paper green and the acid as a circle, which turns purple to pink. In case both shapes and thus the pH values overlap, a mixed colour arises.