Printing technology: pearlescent printing technology
pearlescent printing is a new type of printing that is more popular in packaging printing and anti-counterfeiting printing. It mainly uses pearlescent ink, which is an ink with pearl luster. When the printing pattern changes angle, the color of the ink will change, so that the authenticity can be identified. The printing process of pearlescent printing is basically the same as that of traditional printing. The key is to make it coincide with the main needle in the preparation of special light ink. It 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 the characteristics of pearlescent trembling materials, when selecting pearlescent pigments to mix inks, we should pay attention to the following three relationships:
1. The relationship between the size of the film diameter of pearlescent materials and the flash effect. Pearlescent pigments used in packaging and printing are in sheets. Generally, the distance between the flash sources is large when the film diameter goes, and the flash effect is dispersed; On the contrary, if the sheet diameter is small, the flash source spacing is also small, and the flash effect is concentrated
2. The relationship between the sheet diameter of pearlescent pigment and the flash intensity. The larger the sheet diameter of pearlescent pigment, the more opportunities for its surface to be subject to multiple reflection and refraction of light, and the stronger the flash intensity; On the contrary, the intensity of flash is weak
3. The relationship between the rotating speed of pearlescent pigment 50r/min, the diameter of the flake and the cohesion and the suspension sedimentation in the binder. Generally, the smaller the slice diameter of the special light pigment is, the easier it is to condense, and the smaller the aspect ratio of the particles is, so it is easy to settle in the binder, otherwise it is easy to be suspended
in order to make the pigment in the binder uniform #-o-, we must master the three relationships. According to the density of the binder, we can choose the appropriate piece diameter and aspect ratio of pearlescent pigment. In the ink mixing, we can also add thickener to prevent the pearlescent pigment from settling; Or wetting the pearlescent pigment in advance and then dispersing it in the binder, which can also avoid the disadvantages of particle agglomeration and sedimentation.
the blending method of pearlescent ink is:
④ generally, 1 og pearlescent pigment is added to every 100 g of ink@ After the pearlescent pigment is directly mixed with the binder in the ratio of 1:1, the ink fluidity can meet the printing requirements: ⑦ when mixing the color pearlescent ink, some trace organic pigments can also be added to reduce the cost. Generally, the method of white pearlescent pigment combined with other pigments is adopted, such as adding 1% carbon black to the white pearlescent pigment, and the ancient silver effect can be obtained
generally speaking, But it can also calculate the data at the same time. The light color color blending should be mainly light color, because too much dark pigment is added when blending dark color, which will cover part of the pearlescent luster. In addition, it is not allowed to mix the color pearlescent ink series products. It is different from general-purpose inks. It can use two or more inks to mix into another color. When two or more pearlescent inks are mixed and used together, there will be complementary colors, which will reduce the pearlescent effect instead.
pearlescent ink printing is mainly used in commodity packaging and printing, such as soap packaging cigarette boxes, cigarette holders, greeting cards, wallpapers With the use of 3D printing in all walks of life, food bags are becoming more and more popular, such as paper loading; Film printing: pet, PE, 0PP, PS, etc. in terms of printing technology, pearlescent printing is almost suitable for all kinds of printing, but due to different printing processes, its mechanical performance, technical indicators and operations are different, and the proportion of pearlescent ink is also different. In silk printing, the general proportion of pearlescent ink is: binder 10% - 45%, thickener 0.5% - 1.5%, pearlescent pigment 5% - 3O%, solvent 15% - 35%, and an appropriate amount of additives