Drawing Ink has been formulated with permanent pigments and a water-based natural resin. All the colors can be diluted with water and mixed with one another. India Ink has excellent adherence on paper, cardboard and polyester, as well as on most other surfaces, although it is recommended to use paper with higher grammage to absorb the ink; on fine grained paper the ink may soak through. The colors can be used with a brush, pen, airbrush or fountain pen, depending on the kind of outline and effect desired. Drawing Ink is ideal for outlines, technical drawings and shading and can be applied directly on the surface to obtain a result of high contrast; or diluted with water to achieve graded effects by the application of several layers of progressive intensity of color. Pens, brushes and painting tools can be cleaned with water. For fine pens, it is recommended to use absorbent paper to clean the pen immediately after use, and not allow the ink to dry on the tip. For brushes, clean up with water and dry thoroughly.