Offset gold (silver) ink matters needing attention

The offset ink layer is relatively thin. When printing golden solid and thick lines, two consecutive printing or two step printing processes are often used to achieve the saturation and metallic luster effect of the semi-strong ink layer. The printability of silver ink is better than that of gold ink. Basic printing can basically meet the requirements of general packaging prints. If a large area is required to print silver or the used paper is poor, two printing methods are required. , to show a good silvery luster. Note the following when printing gold (silver) ink on an offset press.

1. Select the base and reprint gold (silver) ink

When printing gold ink with an offset printing machine, it is generally necessary to print the background color (commonly known as the bottoming), that is, to select the ink with strong hiding power and similar color to the gold (silver) ink as the background color, and then print the gold on the ink layer of the background color. (Silver) ink can not only save gold (silver) ink, but also increase the gloss of the gold (silver) ink layer and strengthen the printing effect of gold (silver) ink.

2. Printing gold (silver) ink on the base ink

The quality of the background printing quality is an important factor in determining the printing quality of gold (silver) ink. Therefore, the layout of the printing background ink should be smooth, the ink color of the background color should be high, the drying property should be moderate, and the ink layer should be thick. The drying method of the base color ink is preferably combined with osmotic drying and oxidative conjunctiva drying, and the formation of the crystallization of the underlying color ink layer is not allowed.

When printing gold (silver) ink, superimposition should be performed with the undercoat ink layer still not completely dry, otherwise the gold (silver) ink is not printed, or the adhesion fastness is poor, and the rubbing will fall off.

3. Overprinting other inks on gold (silver) ink layers

In addition to its own metallic luster, gold powder is more reflective than light. If inks of other colors are printed on the gold ink layer, the metallic luster effect of the gold ink layer will be affected. Therefore, this should be taken into account in the design of the printing process, and the full use of the high ink opacity, strong hiding power and other characteristics of the ink, a reasonable arrangement of printing color sequence, try to arrange the golden ink in the last color sequence. If inks of other colors must be superimposed on the gold ink, the area of ​​the graphics should be as small as possible. This will not affect the effect of the gold ink, and it can also prevent the occurrence of printing defects such as poor overprinting.

Source: Guangdong Printing Network