| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing an ink composition for offset printing, the method in which dispersibility of a pigment is improved, the production efficiency of the ink composition is also improved and the installation space of equipment can be saved. <P>SOLUTION: The method for producing the ink composition for offset printing comprises: a premixing step of throwing a pigment-dispersed material containing 5-40 mass% pigment in a tank 20 and agitating/mixing the thrown pigment-dispersed material by using a cutter blade 10 to obtain a pigment-dispersed mixture; a dispersion step of supplying the pigment-dispersed mixture from the tank 20 to a dispersion device 110 to subject the pigment-dispersed mixture to dispersion treatment and obtain a primary dispersion; a return step of returning the primary dispersion from the dispersion device 110 to the tank 20; a circulation step of circulating the contents housed in the tank 20 between the tank 20 and the dispersion device 110 to repeat the dispersion treatment in the dispersion device and obtain a pigment dispersion; and a post-addition step of throwing residual materials for the ink composition in the pigment dispersion-housed tank 20 and agitating/mixing them to obtain the ink composition for offset printing. <P>COPYRIGHT: (C)2013,JPO&INPIT |
