| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a resin for printing ink or a resin composition which does not necessitate formaldehyde in a synthesis process thereof, has a high resin viscosity or a high molecular weight to the extent that the viscosity or the molecular weight is suitable for the resin used for preparation of an ink having wide applications. SOLUTION: The resin for printing ink is obtained by heating and reacting rosin, phenol, an aliphatic polybasic acid and a polyhydric alcohol. The rosin and the phenol are heated and reacted in advance to prepare an addition reacted rosin-phenol to which are then added the aliphatic polybasic acid and the polyhydric alcohol followed by heating and reacting to obtain the resin. The phenol to be used includes carbolic acid (phenol) and the rosin to be used includes an unsaturated carboxylic acid or rosin modified by the acid anhydride thereof.</p> |
