Printing rollers have a good affinity for water. Due to the addition of a special formula in polyurethane materials, which changes their internal molecular structure and introduces and increases factors with good affinity for water, the surface tension and surface water absorption of the material are improved. Therefore, it is used as a water and alcohol series rubber roller for moistening plates with good results. So, how should the printing industry choose to purchase printing rollers? Let's learn about it together.
1. High elasticity
When the printing roller rolls at high speed during ink transfer, it is affected by three types of deformation: sensitivity, hysteresis, and plasticity, therefore requiring the roller to have high elasticity.
2. Wettability
The wettability of the rubber roller determines its affinity for water and ink. Rubber rollers have good oleophilicity and water resistance, allowing ink to spread better.
3. Wear resistance
When choosing printing rollers, choose rollers with good wear resistance, which can easily maintain the capillary gaps on their surface, have strong anti glaze ability, and maintain good wetting properties.
4. High temperature resistance
During the operation of the rubber roller, heat is generated due to the influence of rolling and friction.
5. Viscosity and Cleanability
The surface of the printing roller is smooth, delicate, and flexible, and the ink is not easily penetrated. Meanwhile, the adhesive roller can absorb paper powder, paper wool, and dust during the printing process, resulting in better cleaning performance.
6. Corrosion resistance
Printing rollers should have good resistance to chemical corrosion in solvents, cleaning agents, and dampening solutions, and have a long service life.
The printing industry needs to pay attention to the above points when choosing to purchase printing rollers. In the offset printing process, the key is to control the balance between the water and ink paths, and the ink balance depends on the key components of the rubber roller and ink roller, whose quality directly affects the product quality. This is especially true for gravure printing, relief printing, and flexographic printing.
Editor: Chihiro