目的 研究PP棉滤芯对胶印润版液的过滤净化性能，在满足过滤要求的前提下，为胶印机润版液过滤系统选择合理的过滤级数。方法 设置四级润版液过滤净化系统，以0.5，1 μm孔径的PP棉滤芯作为过滤介质，测量润版液经过每级过滤前后的pH值、电导率和表面张力。结果 以孔径1 μm的PP棉滤芯作为一级过滤，0.5 μm的PP棉滤芯为二级、三级、四级过滤滤芯，经过第4级过滤后，润版液核心参数处于印刷要求范围内，但变化率不足1%。结论 此类胶印润版液过滤装置最优过滤级数为三级过滤。

The work aims to study PP cotton filter element on its performance of purifying offset printing dampening solution and select the suitable filtration stage for offset dampening solution filter system under the premise of meeting the filtering requirements. The 4-stage dampening solution filtration and purification system was set up to measure the pH value, conductivity and surface tension of the dampening solution after each stage of filtration, with PP cotton filter element (bore diameter: 0.5 and 1 μm) as filtration medium. PP cotton filter element with bore diameter of 1 μm was regarded as the filter element at stage 1, PP cotton filter element with bore diameter of 0.5 μm was the filter element at stages 2, 3 and 4. After filtration of stage 4, the core parameters of dampening solution were within the range required by printing, but the rate of change was less than 1%. The optimal filtration stage of such offset dampening solution filter device is the filtration at stage 3.