(7) Bad ink transfer. Cause: The type of ink and printing materials do not match, ink viscosity is too high, static electricity and so on. Solution: Replace ink, adjust ink viscosity, add antistatic agent.
(8) color cast. Reasons: Inaccurate hue of ink, improper ink drying speed, poor ink stability, performance of printing materials, and changes in the printing process. Solution: Replace the ink, adjust the solvent ratio, and adjust the printing process parameters.
(9) Static electricity. Cause: The ink is too thin, the printing speed is too fast, and the environment is too dry. Solution: Add antistatic agent, increase ink viscosity, reduce printing speed, adjust humidity, etc.
In the printing process, the following issues should also be noted:
(1) Use the same brand of ink produced by the same ink manufacturer to avoid printing failures of different manufacturers and different types of inks.
(2) The ink is fully stirred before use, and it is often stirred during the printing process to ensure that the ink system is evenly dispersed.
(3) Each deployment of the ink should not be too much, should follow the principle of "less add, ground plus", not only is conducive to the stability of ink performance, but also can effectively avoid waste; In addition, for spot color inks, it should also be prepared recording.
(4) In the printing process, in order to ensure the quality of label prints and smooth production, certain additives, such as antistatic agents, defoamers, and rewinders, should be added to the ink. Note that the amount of addition must be controlled. Within the prescribed range.
(5) There are many deficiencies in the label printing ink on the market. The most prominent problem is the ink hue deviation problem:
On the one hand, the hue of the same ink produced by different ink manufacturers is different; on the other hand, even if the same ink produced by the same manufacturer has a different batch, the hue will deviate, sometimes even large. For this reason, printing companies often have to stop the commissioning, which is very detrimental to the stability of the printing quality, and brings great inconvenience to production, which seriously hampers the improvement of the quality of printed matter.
There is a certain gap between domestic inks and imported inks, especially in high-end products. Domestic ink manufacturers should improve their technical level and production capacity as soon as possible to drive the improvement of the entire ink manufacturing industry. In order to achieve a better preservation effect, the label printing ink should be stored in a closed container under normal temperature, cool, dry, dark, and ventilated environment.
The following issues should also be noted during the storage and management of label printing inks:
(1) Safety First, store ink as far away as possible from fire and heat sources to prevent accidents.
(2) It is best to maintain a constant temperature in the ink storage room, and the difference between the temperature of the printing shop and the printing shop should not be too different. If the temperature difference between the two is large, the ink should be placed in the printing shop in advance, which is not only beneficial to the stability of the ink performance, but also ensures the high efficiency of production.
(3) In some areas in the north, the winter is relatively cold, and the ink should be kept outdoors to prevent the gel from gelling at low temperatures. If gelation occurs, transfer it to a warehouse with high temperature, or put it in hot water to restore the insoluble matter.
(4) In the storage and management of inks, the principle of “first in, first out†should be followed, that is, the ink first purchased should be used first to prevent the ink from affecting its use effect due to the long storage time.
(5) The ink also has a certain shelf life. If it is stored too long, various components of the ink will be separated and precipitated. Therefore, the ink should not be stored for a long period of time. The general shelf life is one year.
(6) After printing, the remaining ink must be sealed and stored in a dark place. Before reusing it, it must be filtered with a filter of 100 mesh or more, mixed with new ink before mixing.