Pearlescent special ink and printing process

The sustained and steady growth of China's national economy has provided a broader market space for the printing and packaging industry. Among them, pearlescent printing as a special effect printing product for special ink printing will bring endless fun and new profit growth points for many of our packaging and decorating and printing manufacturers.

Pearlescent printing features:

Pearlescent printing, through the organic combination of individualized design and print quality, can create a completely new color space and light color effect on the substrate surface of plain and plain paper and film. Printed substrates print and decorate all kinds of graphics and texts through pearlescent inks, not only to beautify and protect the products, but also to beautify the human living environment and living space with its unique new humanistic concept, and express the common pursuit of people, thus enabling people to Enjoy more colorful and fantastic colors.

Pearlescent flexographic printing ink is a kind of liquid ink similar to Newtonian fluid, low viscosity and high concentration. It is divided into three types: solvent type, water-based type and photo-curing type. In order to maximize and fully demonstrate its pearlescent effect, the transparency of the binder, colorant, etc. used to formulate the ink is first. In the production process, the ink must be in the best suspension-miscible state. To ensure that the ink layer of the printed product can receive plenty of light without losing a large amount of light, so as to show the special optical interference function of pearlescent light, increase the depth and layering of the color, and transform it into crystal clear, colorful, pearl luster. And elegant visual effects.

Pearl ink use method:

Due to the large proportion of pearlescent ink and ink, be careful and thoroughly and evenly stir the pearl ink in the packaging barrel before putting on the machine. In the printing process, the printability of pearlescent flexographic ink is quite good, the stability of the machine is good, and it is easy to operate. As with gold ink, as long as the conditions permit, use a recirculating ink supply device with a closed squeegee as much as possible to avoid sedimentation leading to chromatic aberration and color shift before and after printing, which affects the consistency of the product. Choose a suitable flexographic plate to avoid poor transfer of ink or the occurrence of a plate-laying phenomenon. According to the printing substrate, printing speed to carefully adjust and care pearl ink viscosity and drying speed. Under normal circumstances, the ink viscosity 50 ~ 60sec / 4cup / 25 °C. Printing coated paper and film, suitable viscosity is 20 ~ 30sec (4 cup/25 °C); printing cattle cardboard, gray paper, etc., suitable viscosity of 30 ~ 60sec (4cup/25 °C), (printing speed 120m/min The lower the vehicle speed, the higher the ink viscosity.) The printability and transferability of pearlescent inks have their own characteristics. The material of the anilox roller has a decisive influence on the transferability of the flexographic ink. The ceramic anilox roller has the best effect for pearlescent flexographic printing due to its special ink hole shape and excellent adsorption and release of ink and ink. Pearlescent flexographic printing requires that the fineness of the pearlescent ink match the number of anilox roller lines. Pearlescent ink has a larger particle size than conventional ink. Therefore, in order to ensure the printing quality, certain printing conditions need to be adjusted, such as reducing the number of anilox roller lines to cope with the transfer of larger particles, which also makes the ink layer thicker. To adjust the drying temperature, at the same time pay attention to the smoothness of the paper. The pearlescent effect depends on the amount of ink transferred to the substrate. The thicker the ink layer, the more glossy pearlescent. For this reason, it is recommended to use an anilox roller with a depth of up to 50 μm. According to the standard of printed products, the best printing effect can be obtained by adjusting the printing speed. When printing, it is best to maintain a brief leveling of the ink after it has been transferred to the substrate, so that the pigment crystals are optimally aligned with the surface of the substrate.

Select Pearlescent ink according to the design and decoration characteristics of printed products: full-page printing, it is recommended that you use pearlescent ink of 10~60μm or thicker, because of its good transparency, so that the printed product has a crystal clear, shiny and glittering texture; if it is local printing , choose delicate 5 ~ 25μm, pearlescent ink with strong coverage, so that the printed product gloss soft and delicate, silky feeling, such as satin-like smooth.

Pearlescent brightness and viscosity

The brightness of pearlescent ink is directly proportional to its viscosity, otherwise it is difficult to meet the brightness requirements of printed products. If the brightness is not enough, adjust the squeegee angle, increase the thickness of the ink layer, and increase the brightness. Ink layer thickness and drying speed: With the thickening of the ink layer, it is necessary to increase the drying temperature at the same time, increase the air volume, so as to make the ink film dry and improve the gloss effect. Printing substrate smoothness and pearl effect: After printing, the arrangement of the coloring pigments in the ink layer of the printed product is parallel to the substrate, which determines the pearlescent effect. The main factors influencing the pearlescent effect of printed materials are: ink properties, ink transfer methods, printing processes, and substrate types. The smoothness and smoothness of the printing materials have a crucial influence on the arrangement of pigments. The better the flatness of the substrate is, the better the formation of the pearl specular surface is, so that the incident light can be multiplely refracted at the levels generated by these different optical refractive indexes, thereby exhibiting an excellent pearlescent effect. On the contrary, if the colored particles are scattered and disorderly, resulting in diffuse reflection of the incident light, it can be imagined that the pearlescent effect will be greatly weakened, and it is difficult to achieve the beautifying effect of pearlescent light. Of course, for large particle size light inks, the glittering effect does not depend only on the smoothness of the substrate. Covering the light - a layer of varnish on the top of the cover, not only perfectly protects the ink layer, but also makes the finishing touches and icing on the cake. According to the machine speed, adjusting the viscosity, viscosity, flowability, pH stability, drying speed and leveling of the varnish, it is important to handle the post-printing glazing process correctly and economically. After the surface of the printed material is pressed or embossed, the pearlescent effect will be significantly improved. After printing by dark paper and embossing, it can produce a gift package with special visual gravitational effect. Unbleached kraft paper can be produced with metal luster after being printed by pearlescent printing. Such follow-up processes can be pearl printing. Products add bright colors. In this way, if your equipment investment does not increase, your printing products will be perfect and beautiful. To attract people's attention, they can win customers and take advantage of opportunities. This will enable the company to win the top spot in the fierce market competition. This will add new special effects to our printing, packaging and decorating products and win a broader market share.

Reprinted from: China Polymer Network