Common defects and improvement measures in water-based ink printing

发布时间：2026/07/06 | 浏览量：0

In recent years, water-based ink has been widely used in various applications due to its good fluidity, stable ink quality, and characteristics such as vivid colors, smooth prints, rapid drying, and no environmental pollution. These include: food flexible packaging composite lining printing, plastic surface printing, soft PVC printing, PVC heat shrinkable film printing, PET thermal transfer printing, hygienic packaging material printing, plastic water-based screen printing, and water-based surface treatment. Moreover, it can be customized according to customer needs. However, during the actual printing process, special attention should be paid to aspects such as ink viscosity and dosage ratio. If not handled properly, issues such as fuzzing, bubbling, and plate blockage may occur. So, what causes these problems and how can they be improved? Let’s take a look at a comprehensive solution for application, common defects in water-based ink printing, and improvement measures!
Phenomenon 1: Poor hue
Improvement measures:
1. If the viscosity of the ink is low, add some of the original ink to increase its viscosity;
2. If ink separation or sedimentation occurs, it is necessary to stir the mixture thoroughly;
3. Check whether the printing plates are aging and replace them in a timely manner;
4. Check the transfer of ink from the roller to the printing plate.
Phenomenon 2: Slow drying of imprints
Causes: The imprint dries too slowly, primarily due to factors such as high ink viscosity, thick ink layer, poor ink drying, or strong water resistance of the paper.
Improvement measures:
1. First, check whether the dryness of the ink is appropriate. It is best to use quick-drying ink;
2. If the viscosity is too high, dilute the ink to reduce its viscosity;
3. Reduce the ink volume appropriately and add a quick-drying agent to adjust the drying degree of the ink;
4. Replace the paperboard with one that has good absorbency.
Phenomenon 3: Formation of burrs
Causes: The burr phenomenon may occur due to factors such as the ink viscosity being too high, the ink drying speed being too fast, the pressure between the roller and the printing plate being too strong, or the presence of paper dust mixed in.
Improvement measures:
1. Check whether the viscosity of the ink is too high. If the viscosity is too high, further dilute the ink;
2. Add a slow-drying agent to the ink appropriately to adjust the drying level;
3. Check whether the pressure between the roller and the printing plate is too strong, and reduce the plate pressure appropriately;
4. Before using the ink, filter it through a steel mesh.
Phenomenon 4: Poor printing
Causes: When we observe that the paperboard is thin and the text is not printed clearly, it is likely due to poor printing plate accuracy, excessive plate pressure, high ink viscosity, and aging of the plate material, which results in loss of strength.
Improvement measures:
1. Check whether the thickness of the printing plate is uniform and whether the hardness is too low, and appropriately correct the height difference and hardness of the plate surface;
2. If the plate pressure is too high, it needs to be adjusted;
3. If the viscosity is too high, further dilute the ink;
4. Check whether the printing plates are aging and replace them in a timely manner.
Phenomenon 5: Ink Blistering
Causes: Ink foaming can lead to phenomena such as white spots, sand holes, and water marks on the surface of the printed product. This is mainly related to insufficient ink anti-foaming and defoaming capabilities, insufficient ink circulation, air entering the return pipe, and excessively high ink viscosity.
Improvement measures:
1. Add an appropriate amount of defoaming agent and pay attention to increasing the circulation volume of the ink;
2. Try to avoid inserting the return tube into the ink to prevent air from entering;
3. If the viscosity is too high, it should be diluted appropriately.
Phenomenon 6: Watermark on the printed surface
Causes: The formation of water marks on the printed surface is related to low viscosity printing, excessive coating thickness, excessive dilution of ink, poor ink absorption of the paperboard, as well as poor fluidity and quality of the ink itself.
Improvement measures:
1. Try to choose medium to high-grade inks with good fluidity;
2. If the ink is overly diluted, a thickener or the original ink should be added to increase its viscosity;
3. Replace the paperboard with one that has good absorbency.
Phenomenon Seven: Gelatinization of ink
Causes: Due to improper storage, incorrect use of ink solvents, and poor quality of ink, the ink loses its fluidity and solidifies into a gel-like state.
Improvement countermeasures:
1. Store the ink in a sealed container in a cool and ventilated environment;
2. Use the dedicated and matched solvent;
3. Try to choose medium to high-grade inks with good fluidity.
Phenomenon 8: Printing blockage
Causes: During the printing production process at the printing outlet, the printing screen often gets clogged. The main reasons are poor fluidity of the ink, excessively high viscosity, rapid drying of the ink, or infiltration of ink into paper dust and dirt.
Improvement measures:
1. Adjust the air pressure of the ink supply pump to enhance the fluidity of the ink, or choose medium to high-grade inks with good fluidity;
2. If the viscosity is too high, further dilution is needed to reduce its viscosity;
3. Add a slow-drying agent to slow down the drying speed of the ink;
4. Before using the ink, filter it through a steel mesh.
Phenomenon 9: Poor color overlay printing
Causes: The occurrence of poor color overlay is largely related to the base color. When the base color is printed too heavily, the viscosity of the base color is too high, the drying speed of the base color ink is too slow, or the base color is slightly darker, poor color overlay may occur. Additionally, high surface tension of the top color and poor penetration of the paperboard are also contributing factors.
Improvement measures:
Generally speaking, the printing sequence for tinting is from light to dark colors, with ink viscosity increasing from low to high. To address the above issues, we can do the following:
1. Adjust the background color to be slightly lighter than the colored part;
2. Check whether the base color printing pressure is too high, and appropriately increase the color printing pressure;
3. If the viscosity of the base color is too high, it is necessary to reduce the viscosity of the base color appropriately;
4. Add an appropriate amount of desiccant to accelerate the drying speed of the base ink;
5. Improve the surface tension of the color, and replace with paperboard with good permeability.