Printing whiteout is the most common and difficult quality problem in corrugated carton production, which will cause the surface of the carton to be printed in an unattractive way. If there is a large area of bleaching, it will be regarded as a defective product, resulting in production waste. Printing personnel need to learn to judge the crux of the problem based on the appearance, to quickly deal with it.
 
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Improper pressure adjustment
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1, the version of the pressure (on the pressure) pressure is not enough white (printing cylinder and anilox roller pressure): the main manifestation of the printing surface print is not complete, the print pattern edge clean, and the print pattern in the cardboard indentation of the print, as long as the hand modeling printing white place can be found here on the cardboard has a bumpy feeling, this phenomenon once it occurs is to indicate that the version of the pressure is not enough.
If the printing press group to open, view the printed page, the amount of ink on the page is not enough that is also insufficient pressure of the printing plate, resulting in the printing of the phenomenon of whitening. General printing white area will be larger.
2, printing pressure is not enough white (pressure roller and printing cylinder pressure): printing pressure is not enough white phenomenon and the lack of plate pressure has the same thing, but there is a very obvious difference, that is, there is no unevenness in the printing pattern on the cardboard, the printing plate has enough ink.
Improvement method: these two types of whiteout phenomenon is the best solution, is to adjust the respective pressure to the appropriate position, it can directly improve the printing whiteout phenomenon.
 
 
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Low ink viscosity
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Ink viscosity low printing white phenomenon, the most obvious is the printing pattern out of the ink color is light, and printing white showing pinhole phenomenon, the printing pattern is not real looks very false.
Improvement method: the appearance of such a white first of all to measure the viscosity of the ink, you can increase the viscosity of the ink or add some new ink, you can solve the phenomenon of printing white.
 

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Printing plate
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Printing plate used for a long time or printing plate ink dirt is too much, it will reduce the ink transfer volume of the printing plate, when the ink transfer volume is reduced, the phenomenon of white printing will often occur.
Improvement method: In the preparation stage before printing, we need to check whether the printing plate is good, check whether the printing plate pressure is normal, you can check whether the printing layout has enough ink volume
 
 
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Anilox rollers 
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Anilox roller cleaning is a direct impact on the printing situation, a large part of the anilox roller clogging did not get cleaned up, so that the anilox roller ink carrying capacity is small, which leads to the phenomenon of printing white.
Improvement methods:
1. In the preparation stage before printing, we need to check whether the anilox roller is clean. 2.
2. After cleaning the machine after each shutdown, we need to use professional cleaning agent to maintain the anilox roller.
 
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The reason of sheet
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Printing whitening caused by sheet is mainly reflected in the de-inking of printing pattern. If the color block white phenomenon is mainly reflected in the middle part of the paper white serious, because the ink absorption of paper is very poor, the ink can not penetrate into the paper inside, the ink floats on the surface of the paper, as long as the hand rubbing the ink is found to have shedding phenomenon.
Improvement methods: such as encountering this type of printing white on the printing pressure and plate pressure do not always add, must be from the ink side of the work, in the ink to increase the resin content and penetrating agent. This method is more effective than other solutions.
 
Of course, the phenomenon of printing white and solve the phenomenon of printing white far more than these aspects, the above kinds of species is only the production process of the most common phenomenon of printing white, welcome to communicate with you!