The Speedball Water-Soluble Block Printing Ink Retarder will slow down the drying process when mixed with water-soluble block printing inks, so you can work on your project at your own speed.  It comes especially in handy when working in warm and/or dry climates.  The retarder will not change the viscosity of your ink and is suitable for block and linoleum printing.  This water-soluble block printing ink retarder has excellent transfer tack which ensures even coverage and produces minimal odor.  This ink retarder can only be mixed with water-soluble printing ink.  The Speedball Water-Soluble Block Printing Ink Retarder is gluten free and ACMI AP Certified so it is safe for everyone to use both at home and in the classroom.