PENETRATION PREVENTING AGENT, METHOD FOR PREVENTING PENETRATION AND SOLVENT BASED INK

摘要

A penetration-preventing agent for ink-jet ink is provided to prevent a solvent-based ink from penetrating into a porous printing medium, thereby ensuring excellent water resistance and water repellency of an ink coating layer. A penetration-preventing agent for preventing solvent-based ink jet ink from penetrating into a printing medium comprises a rosin type resin having a weight average molecular weight of 16,000-50,000. The rosin type resin includes a rosin-modified phenolic resin. The printing medium has a hydrophilic porous surface as a printing surface. The printing medium includes a printing plate for off-set printing. The rosin type resin is used in an amount of 5-25 wt% based on the total weight of the solvent-based ink.