Special anti-counterfeiting printing: constant change often (below)

This is a gravure shadow technology. The use of different gravure lines in different vertical and horizontal lines of light on the same part of the paper made of two kinds of graphics, that is, the use of horizontal and vertical lines reflect the principle of different, when the paper to look at the light source lying flat in front of the concave The ridge of the printed horizontal line casts a shadow on the side of the backlight and becomes a visible graphic, otherwise only the graphic of the vertical line can be seen. This technique is often used for security printing such as card. This printing technology has been used on passports in Canada, Sweden, the Czech Republic, Uruguay and my country.

Image Mixing Anti-counterfeiting Printing Technology

The use of an electronic program-controlled camera allows the captured image to be intermixed, distorted, or overlapped with other images, so that the printed image must use a special decoder to recognize the original image. Because the image is distorted, the print cannot be copied with a color copier or scanner. This anti-counterfeiting technology is mostly used for card and some packaging security printing.

Special glossy printing technology

Special glossy printing is a new type of anti-counterfeiting printing technology that is popular in packaging printing in recent years. The special glossy printing process currently includes metal luster printing, pearl printing, pearl luster printing, refractive printing, variable gloss printing, laser holographic iris printing, crystal luster printing, imitation metal etching, and matte printing. Among them, the metallic glossy printing uses aluminum foil type metal pen paper, and with a more transparent ink, a special metallic luster effect is formed on the printed material. Pearlescent printing is the first printing on the surface of the silver paste, and then with a very transparent ink, silver flash through the ink layer reflects a pearl effect. Pearl sheen printing is printed with inks that incorporate mica particles to produce a glossy effect similar to pearls and shellfish. Refractive printing is the unique effect of using a refraction plate to emboss a pattern on a printed crystal with a certain pressure to produce light refraction. The matt printing adopts the matt ink printing or common ink printing and then covers the matting film, which can produce the weak gloss characteristics of the matte, so it also has better anti-counterfeit effect.

Gravure printing technology

This is one of the better anti-counterfeiting printing technologies commonly used on banknote printing. Gravure printing is one of the oldest and most complex printing techniques and it is difficult to imitate. Engraving intaglio printing technology refers to the fact that the graphic part of the printing plate is convex, and the ink printed on it is also convex, and the graphic lines are clear and distinct, and the touch can feel. Its main anti-counterfeit feature is that the gravure printing uses the pits and inks carved in the original image and text, and the thickness of the lines and the density of the ink can be arbitrarily controlled during the engraving, which increases the difficulty of imitation and forgery, especially the depth of the ink pit. The possibility of realistic carving in the style of the printed picture is very small.

Concave engraving gravure has manual engraving, mechanical engraving, electron beam engraving or etching plate and many other. The method of monochromatic printing is the same as multi-color printing. The difference is that for a consistent pattern, different colors of ink are applied in segments, and the joining is very accurate. The printing is once printed on the ticket surface, which requires a very high standard. The level of technology is difficult for general counterfeiters to achieve.

If the combination of anti-counterfeiting printing and anti-counterfeiting ink technology is combined, better anti-counterfeit effect can be produced. Some anti-counterfeit printing inks have larger pigment particles and require thicker ink layers. The gravure printing has a stronger texture and the combination of the two results in double anti-counterfeiting and decoration effects. For example, the use of fluorescent ink for engraving and gravure printing not only ensures the concave and convex feeling of gravure printing, but also reflects the use effect of fluorescent ink, and both of the secret anti-counterfeiting functions can also be guaranteed.

(author / Qi Cheng)

Source of information / China Packaging News