Speedball Fabric Block Printing Ink is a permanent oil-based ink that provides bold opaque color. Excellent on cotton, polyester blends, linen, rayon, and other synthetic fibers. Can also be used on paper and cardboard, but should not be used on nylon. Cleans up easily with soap and water. Printed fabrics can be laundered after curing one week at room temperature. ACMI AP Non-Toxic, conforming to ASTM D-4236. Sold in 75cc (2.5 oz.) tubes.