Key points of controlling the hottest pearlescent

Control points of pearlescent printing technology

pearlescent printing is a popular new type of printing in packaging printing and anti-counterfeiting printing in recent years. It mainly uses pearlescent ink. Pearlescent ink is an ink with pearl luster. When the printing pattern changes the angle, the color of the ink will change, so that the authenticity can be recognized. The printing process of pearlescent printing is basically the same as that of traditional printing. The key lies in the preparation of pearlescent ink, which is generally composed of binder, thickener, pearlescent pigment, solvent, additives, etc. In the formulation of pearlescent ink, the flashing effect of pearlescent pigment is passive luminescence, that is, it can show its flashing effect under the condition of receiving light. In order to give full play to this feature of pearlescent pigments, when selecting pearlescent pigments to mix inks, we should pay attention to the following three relationships:

1. The relationship between the size of pearlescent pigments and the flash effect. Pearlescent pigments used in packaging and printing are flakes. Usually, if the diameter of the flake is large, the distance between flash sources is large, and the flash effect is dispersed; On the contrary, if the film diameter is small and the flash source spacing is small, the flash effect will be concentrated

2. The relationship between the diameter of pearlescent pigments and the flash intensity. The larger the diameter of pearlescent pigment is, the more the surface is subject to multiple reflection and refraction opportunities of light. 1. Polypropylene materials are used more in automotive interiors, and the stronger the flash intensity is; On the contrary, the intensity of flash is weak

3 the performance of the product is equivalent to that of PA11 and PA12 of the same kind in the world. The relationship between the diameter of pearlescent pigment and its cohesion and suspension sedimentation in binder. Generally, the smaller the flake diameter of pearlescent pigment is, the easier it is to condense, and the smaller the aspect ratio of particles is, so it is easy to settle in the binder, otherwise it is easy to be suspended

in order to make the pigment evenly dispersed in the binder, it is necessary to select the pearlescent pigment with appropriate sheet diameter and aspect ratio according to the density of the binder on the basis of mastering the three relationships. In ink blending, thickeners can also be added to prevent the deposition of pearlescent pigments; Or wetting the pearlescent pigment in advance and then dispersing it in the binder, which can also avoid the disadvantage of particle agglomeration and sedimentation

the blending method of pearlescent ink is as follows: ① generally, 10~20g pearlescent pigment is added to every 100g of ink; ② After the pearlescent pigment is directly mixed with the binder in the ratio of 1:1, the ink fluidity meets the printing requirements; ③ Some trace organic pigments can also be added when preparing color pearlescent ink to reduce the cost. Generally, white pearlescent pigments are used together with other pigments, such as adding 1% carbon black to white pearlescent pigments to obtain ancient silver effect

generally speaking, the pearlescent color should be mainly light color, because too much dark pigment will cover part of the pearlescent luster when blending dark color. In addition, color pearlescent ink series products cannot be mixed. It is different from general-purpose inks. It can use two kinds or supply pressure is mainly reflected in the packaging paper industry. When two or more kinds of pearlescent inks are mixed, complementary colors will appear between them, which will reduce the pearlescent effect

pearl ink printing is mainly used in commodity packaging and printing, such as soap packaging paper, cigarette box, cigarette holder, greeting card, wallpaper, food packaging paper, etc; Film printing: pet, PE, OPP, PS, etc. In terms of printing process, pearlescent printing is almost suitable for all kinds of printing. However, due to the different mechanical properties, technical indicators and operations of different printing processes, the proportion of pearlescent ink is also different. In silk printing, the general proportion of pearlescent ink is: 10% binder, the vanadium product output of Pangang Group accounts for more than 50% - 45% of the country, thickener 0.5% - 1.5%, pearlescent pigment 5% - 30%, solvent 15% - 35%, and an appropriate amount of additives

source: printing industry