1, the stability of printing ink

Stable printing ink quality is the key factor to control printing color difference. Change if the quality of printing inks, will lead to the printing effect difference, especially the part of the customer to reflect the uniqueness of the brand and increase anti-counterfeiting, will use the color ink, and the color of the ink deployment must be accurate to guarantee the stability of the ink color, this requires the ink technology have higher requirements. In addition, printing ink will have the problem of increasing volatilization stations, which will also have a certain impact on the printing color difference, so in addition to control the contrast in the ink adjustment, but also pay attention to the change of ink viscosity in the printing process.

2, printing plate inking performance

Printing plate inking performance, especially after a long time of plate wear inking performance. While the current plate technology has improved, to some extent, reduces the printing color difference problem, but wear plate after a long time will reduce the inking performance, caused by imprinting shallow, ink layer saturated, encountered such a problem if simply increasing the printing pressure and can not fundamentally solve the problem, On the contrary, it will cause further wear of plate and increase of printing color difference, and may also reduce the compressive strength of packaging products as a whole.

3, printing pressure and speed control

The uniformity of printing speed and printing pressure will make the color of printing produce different effects. On the one hand, when the printing speed is accelerated, the amount of ink will increase with the increase, the ink layer will become thicker, the corresponding color will be heavier; On the contrary, when the printing speed is reduced, the amount of ink decreases, the ink layer becomes thin, and the imprinting will become light, resulting in the amount of ink to reach saturation. On the other hand, if the printing pressure is too large, the amount of ink is small, it will cause imprinting; If the pressure is too small, the gap between the rollers increases, and the amount of ink is too much, it will cause the ink layer to thicken and the hue to become heavy, especially in dot printing, which is easy to cause the phenomenon of pasting. Therefore, to ensure the stability of printing effect, it is necessary to do a good job in the control of printing speed and printing pressure.