What is the cause of the color difference in the production of metal signs

In the production process of metal signs, the color difference of signs mainly includes: pure ink color difference, overlapping color difference, network deformation color difference, color difference caused by printing inaccuracy, color difference caused by abnormal wetting system, color label printing and coating production process. Today, we mainly discuss the causes and control methods of ink color difference and overlap color difference:

First, ink color difference

Reasons: such as primary color or characteristic ink, the main reasons for the actual color difference are as follows: ① the color adjustment is not accurate, the type and proportion of ink is not reasonable, can not meet the printing requirements; ② The printing properties of ink are related to the printing press and drying room. Improper performance; ③ Ink color, the thickness of the ink layer is not appropriate or the amount of ink is large.

Control methods: (1) Collect the data in the actual printing process of metal signs, clear the relationship between the ink layer thickness and solid density, and control the amount of ink in the printing process; The printability of the ink should meet the objective conditions of printing. The viscosity and fluidity of ink should be adjusted according to the nature of the substrate, the speed of the machine and the type of graphics. Machine speed and solid printing require inks with low viscosity and high fluidity. On the contrary, the opposite is true; ③ When preparing ink, the printing sample should be used as the standard. If possible, establish a database of ink tone standards for future deployment. Standard basis.

Two, overlapping color difference:

Causes: including network cable and solid color background, overlapping causes include network cable and solid color background: (1) improper color sequence; (2) ink viscosity is not stable; The ink is not balanced, the ink cartridge and water tank adjustment is not reasonable, the operation is wrong.

Control methods: (1) Control the thickness of the ink layer and ink viscosity; ② Reasonable arrangement of the printing order of metal signs: generally print secondary color, and then print the main color. Print colors with low dot coverage first, then colors with high dot coverage. Print the screen first, then the bottom. Print high viscosity ink first, print dark color, then print light color. Graphic area is small, print first, graphic area is large. Print the dark color first, print the high brightness first. In fact, the color order should be adjusted according to different content and characteristics; Adjust the ink and water bucket, control the ink balance.