One.The color card is different from the color determined by the user because the current color card and color system is provided by the offset printing system, so when the printing parameters during the screen printing process will cause color change, so it still needs to fine tune, the ink volume affects the ink color.The ink of ink is gradually increased in the order of flat, gravure, convex and silk printing, as shown in the following table, so the ink printing in the three primary colors is very difficult to print, because every variable in the screen printing process of silk printing affects the thickness of the ink layer, thus affecting the color of the printed matter.
Ink thickness and transfer rate of several printing methods
Mean ink layer thickness (U) transfer rate (%)
flat printing 0.7~1.430~50
gravure printing 1.030~50
convex printing 8.050~60
screen printing 6.0~10090~100
Two、The appearance of color
The appearance of color is affected by the transmittance, reflectivity, identical foreign body phenomenon (that is, the two colors very match under the same light source, but do not match under the other light source), observation conditions, lighting, ink layer thickness, ink opacity, overprinting, bearing properties and other variables.
Three、Influence of the printing products.
Sursurface of the products, treatment, ink absorption and surface color.
Four、Ink layer thickness
Ink thickness can cause a color change.The ink thickness is greatly affected by the diameter, tension, type and thickness of the mesh. In addition, the shape and hardness, scraping pressure, scraping speed, scraping Angle, mesh distance, pressure, speed, shape of the ink plate, the ink thickness is also different.
Five、The change of mesh plate tension and other factors cause the change of color phase
Six、Standardization of the light source and observation conditions.
Observation room with a specialized light source.With the spectrometer, each color has its own spectral curve.
Seven、Color difference
That is, different colors have different color differences, which can be measured by the spectral detector.The human eye can distinguish the color difference is 1DE, the computer output sample color difference is 2DE, yellow color it has 3DE with the target color, and gray can only have 0.5DE between its target color is acceptable.
Eight、When the color content is 100% ink, the three primary colors have their own different mesh, the highest color density is: yellow (Y) 200~240 mesh, magenta (M) 200~240 mesh, cyan (C) 180~200 mesh, because the three primary color can not use the same number of mesh, will make color strength loss, there are two solutions:
1、Use a wire mesh of the individual order numbers;
2、When using the same mesh screen, we must pay attention to increase or decrease the color ink, so as to achieve the color of the original copy.
Nine、Accurate amount of special color inks is deployed.If the ink mix too much, residual ink cause waste, if too little, you need to deploy again, such as complex color, the second and exactly the first deployment of ink, so affect the product quality, general deployment should be slightly more than the actual dosage, and the actual printing consumption mainly from the area of the printing, the number of printing, ink thickness and so on several aspects to consider.
As can be seen from the above discussion, color matching is not simply mixing several colors together, but a complex technical engineering. Only by mastering the screen printing process and color matching principle can we match the ink color well and become a qualified ink adjustment technician.