Precautions for Printing with Pearlescent Ink in Silk Screen Printing

At present, the competition in the tobacco label printing industry is very fierce. The cigarette factory's requirements for packaging are also getting higher and higher. To get an invincible position, the cigarette pack printing factory has to constantly introduce new products. If pearl ink is used properly, it can Showing a lot of special effects.

For the choice of printing methods, we must first analyze the product. Each product has different requirements for surface effects, some require coarse pearlescent pigments (pearlescent effect is obvious), some require fine pearlescent pigment particles (beautiful pearlescent effect), and for coarser pearlescent inks, the use of screen printing is better. Instead, use gravure. Because the pearlescent pigment particles used for screen printing are relatively large and the edges are rough, when the light is irradiated to the surface, the reflected light is more, and the color thereof is strengthened and brighter, resulting in a “shiny” effect, such as in Jiangxi Province. Nanchang cigarette factory "Laoshan" smoke standard.

For some special pearlescent pigments, when light strikes the surface, the interference color can be seen in the direction of the reflection angle. In the direction of the scattering angle, the complementary colors of the interference colors can still be seen because the light passes through the thin layer. For example, when printing black ink on pearlescent ink, due to the refraction effect of pearlescent pigments, the angle of reflected light is not the same, and the effect exhibited is also not the same, and the sense becomes blackish green. The choice of pearlescent ink is not the same, the performance of the effect is not the same, such as brown will become dark red.

One is the "burst" of the substrate. This problem usually occurs when the cigarette label is printed with pearls. If you use pearlescent ink on soft bags, you have to use finer particles of pearlescent pigments and use gravure printing. However, due to the thin substrate of the soft package and the high pressure of the gravure printing, the bursting problem is relatively difficult. control.

The second is paper deformation. When infrared drying is used or the pearlescent printing product is naturally dried, the paper of the cigarette label soft pack is easily deformed, and the process control is more difficult. However, the situation of printing gold and silver cardboard is much better, and paper with a larger amount of ration is more suitable for pearl printing. General cigarette paper, if it is 230-250g/m2, is very advantageous for pearlescent printing.

The third is whether the product has odor. Smoke labels have stricter odor requirements for packaging. The scent of the pearlescent pigment itself is not large, but sometimes the pearl ink is not adjusted well, resulting in a large odor produced by the product. By improving the ink and printing equipment, this problem can be effectively avoided.

The fourth is the color difference of the printed matter. Due to the difference in the particle size of the pearlescent pigments, there is a problem that the color difference control is difficult in the printing process. When using screen printing, it must be fine pearlescent pigments first transferred through the screen to the substrate, while the coarse particles are blocked by the screen, so as the printing progresses, the large particles of pigment build up. More often than not, the color of prints will be printed more shallowly, resulting in color differences.

Fifth, the amount of ink is relatively large. The coarse pearlescent pigment particles can also lead to a relatively large amount of ink and the particles are too coarse. The pearlescent pigments will leave residues in the ink, which are difficult to separate and cause ink waste. When using pearlescent ink, be sure to use it within the shelf life, and be sure to mix evenly when using it.