International banknote printing paper anti-fake technology

The paper that prints banknotes is different from ordinary ordinary printed paper, and is manufactured using special methods. Because paper is not easy to copy, each country regards special papermaking technology as an important aspect of anti-counterfeiting. Banknote paper anti-counterfeiting mainly includes the following points.

(1) Watermark. Watermarking is the use of special techniques in the papermaking process to make the density of paper fibers non-uniform and the formation of different thickness, Yingguang can show a pattern of light and shade, clear patterns, patterns. The watermark of banknote paper can be divided into fixed watermark, semi-fixed watermark and full-watermark watermark. The full version of the watermark fills the entire banknote paper with a watermark pattern. A fixed watermark is a fixed part of a banknote that has a watermark pattern. The semi-fixed watermark is a trajectory that continuously shifts and displays the fixed watermark in a certain area of ​​the banknote, so that a continuous multi-shot effect appears. There are many types of banknote watermark patterns and graphics in various countries. There are geometric patterns such as circles and squares, as well as plants and animals such as flowers, grass, lions, tigers and horses. Fixed watermarks often use the portrait of a person's profile.

The watermark of a banknote can be seen in the sunlight or light perspective, and if the banknote is laid flat and does not meet the light perspective, the watermark is generally not visible. This effect is evident on new banknotes. In the case of old banknotes that have been in the market for a long period of time and are subject to friction and rubbing, the watermark may show a dirty outline, but if you look closely, you can see that the actual watermark is still contained in the banknote paper, and the sandpaper is Become one.

(2) Security line. The security thread is a thread made of special material that is clamped into a fixed position in the paper during the papermaking process, and makes this thread a structural part of the paper. The initial security line is a kind of metal line. When you look into the banknote, you can clearly see the existence of the security line. However, if the banknote is laid flat, the line cannot be seen. In recent years, the safety line technology has been widely developed. Due to its different raw materials, different widths and lengths, different positions, quantities, and different depths, different manufacturing processes and detection methods, there are many types of safety lines. For example: opaque plastic safety thread, is a line made of opaque gray plastic film or polyester film; opaque dashed safety line, can see the dashed line made up of points when viewing light; microtext safety line, microtext is printed on On the security line, you can see the words on the security line on the way to the light or with a magnifying glass; the multi-color security thread, a security thread can have various colors such as red, green, and blue; the fluorescent security thread can be seen under ordinary perspective The dark colored security thread, if viewed through ultraviolet light, displays bright blue-white fluorescence or segments of light of different colors; the invisible security thread, under normal light penetration, does not see the security thread, but through a special machine Displays the presence of a security thread. There is also a "window-type" security thread, in which part of the security thread is in the paper layer and a part of the security thread is exposed on the paper surface.

(3) Fiber filaments. This is a papermaking process in which a special filament is incorporated into the pulp, or a specially made filament is withdrawn on the surface of the paper before the paper has been shaped to form a paper with filaments. Some of the filaments used are natural silk, some are synthetic nylon filaments, dyed in various colors such as red, green, and blue. There are fluorescent fibers that can be seen under UV light. The distribution of fiber filaments can form a variety of combinations of anti-counterfeiting structures, some are evenly distributed in full version, some are only added in a fixed position, and some are distributed in paper at different densities, or within the paper layer, or on the surface of paper. . The same fiber can be seen on both the front and back of the banknotes, while on the other side the paper is clear and the other side is blurred. The length, thickness, and shape of various banknote fiber filaments have their own characteristics.

(4) color points. The color point is a colored plastic wafer, approximately 1 millimeter in diameter, which is mixed with pulp during the papermaking process, resulting in the formation of colored dots within the paper. Colored circles can also be made fluorescent to form fluorescent dots.

(5) The fluorescence and non-fluorescence of the paper. The paper used in banknotes is generally made of high-quality wood pulp or cotton fiber. The texture is relatively pure and free of impurities. Therefore, it is not necessary to use chemical reagents and other measures to reprocess it. Therefore, the banknote paper generally has no obvious fluorescent display. . In general, counterfeit banknotes emit blue fluorescence under ultraviolet light.