Security paper

1  banknote printing paper. The carrier used for banknotes, such as banknotes, is different from general printing paper. In particular, the banknote printing paper is made of tough, smooth, crisp, and wear-resistant banknote special paper. This paper is durable, non-pilling, folding, and non-breaking. Its papermaking materials are mainly long-fiber cotton and hemp. Some countries have also added their own unique properties to the pulp, such as the Japanese ink-printing paper pulp has three components; the French franc banknote paper pulp for the Ale River. The printing paper used by the U.S. Department of the Treasury was contracted by the famous companies Coco and Talton of Massachusetts. A banknote printing paper with red and green fibers was jointly developed by the US Department of Finance and the two companies. It was created in 1879 and is still in use today. Its raw materials are used clothes, large purchases of cotton skirts, remove white fabrics. The recipe has been kept secret. Many forgers have analyzed their ingredients since 1879 in an attempt to make such banknote printing paper. This paper contains 75% cotton and 25% linen. The original linen in the paper was 100%, then it was changed to 75% and changed to 50% again. This paper has a certain amount of red and green fiber filaments.
In recent years, in order to extend the useful life of banknotes, some countries have developed and applied plastic instead of paper banknotes for printing money. In 1966 Australia discovered an organized group trying to fake $10. In 1968, the Federal Reserve Bank of Australia commissioned the Scientific and Industrial Research Organization (CSIRO) to study the use of polymer (plastic) materials for banknote printing paper. The plastic banknotes were durable, wear-resistant, tear-resistant and resistant to contamination. In 1988, when Australia was founded, the bank decided to issue a new AUD 10 commemorative ticket for the year (issued on January 27, 1988). Its size and style are the same as the current 10-yuan standard, and current banknotes continue to be issued. There are different changes in the color of plastic banknotes under different lighting angles.

2  No fluorescent special paper. General paper is fluorescent under UV irradiation. As a result, banknote printing paper and some valuable securities or notes are printed using special paper without fluorescence. For example, the paper bases of the national banknotes, passports, and some tickets are not fluorescent, so it is easier to reveal additional fluorescent graphics.

3 纸 paper with trace amounts of additives. Using the principle that organisms have an anti-metabolite specific reaction, a very small amount of anti-elements is added to a certain part of pulp or paper. When detecting, it is combined with the corresponding specific antibody, and the presence or absence of the reaction of the marker, fluorescence, etc. is used to distinguish the authenticity from the others. Trace chemical elements can also be added to the paper to distinguish between true and false.
The United States is researching and developing a special man-made fiber or using genetic cotton to make paper and printing dollar security.
There is a chemically-engraved paper added to the pulp or a special compound added to the glue when sizing on the surface of the paper. The chemically engraved paper can develop color or show fluorescence when coated with a specific chemical reagent. According to reports, tickets for a ball game abroad are printed on this type of paper. As long as the pen is immersed with a special reagent, a pen on the face of the ticket will be displayed. Black strokes will be displayed at the crossing point, and there will be no false tickets. This is true or false.

4 watermark (Water mark). In the papermaking process, a watermark printing plate that has been designed in advance is installed on the screen, or is pressed by a printing roller. Due to the difference in height, the paper pulp has different thicknesses and corresponding densities. After the paper is formed, the density of the pulp in the graphic and text is different, and the light transmittance is different. Therefore, when the light is observed, the original graphic design can be displayed. These graphic images are called watermarks. In 1666, banknotes with special watermarks were issued for the first time in Stockholm. In 1772, there was a text watermark on the banknotes in Saxony, Germany. The family crest on the Schleswig-Holstein bill in Germany in 1802 and the floral watermark on the Baden bill in 1849 were still rare at the time. By the end of the 19th century, most European banknotes used watermark printing paper. Watermarks are fixed watermarks, semi-fixed watermarks, and not fixed watermarks. The fixed watermark must be fixed at a certain position in the body of a banknote, passport, certificate, etc., and it is usually matched with the visible image or other anti-counterfeiting measures. For example, in China's 1990 edition of 100 yuan and 50 yuan, there were Mao Zedong and the worker's head fixed watermark in the watermark window, and a fixed portrait watermark on the 10 yuan currency. Semi-fixed watermark The distance and position between each set of watermarks are fixed, and each group is continuously arranged on the paper. Therefore, it is also called continuous watermark. This kind of paper is used for special paper. The watermark in an unfixed position is distributed on the full version of the paper or ticket, so it is also called a full version of the watermark. For example, the watermarks of the distant view of Mount Fuji and close-range cherry blossoms, which are printed in RMB 5 and RMB 1 in China, are clearly structured and three-dimensional. It is like a light realism ink painting. Vivid, showing superb technology, craftsmanship, is superior. The watermarks of other countries' passports use line drawings, such as the Maple Leaf fixed watermarks on the Canadian passports’ passports, and there are two shades of shades and two shades. It is reported that a new type of transparent watermark has been developed abroad and can only be seen and identified by viewing it from a certain angle and cannot be copied by a scanner.

5 silk yarn, color dot encryption paper. Fiber filaments or color dots are added to the pulp during papermaking.
In early 1880, Prutu National Bank for Printing Co., Ltd. purchased the patent rights for printing paper, named after the inventor James Wilcox. This kind of paper is the color of plant fibers added to the pulp, which is the prototype of modern security fiber paper. At the time, some counterfeiters had tried to imitate the paper with added plant fibers by applying human hair or bristles.
In 1906, Giuseppe De Leounde of Leipzig, Germany cut the printed paper of different colors into the same length of paper and added it to the warm paper web to make a special anti-counterfeiting paper and applied for a patent. In 1939, it was improved. The printed metal wafers were added to the pulp to produce banknote paper, and a patent was filed.
There are two types of fiber incorporated into the pulp, colored fibers and colorless fluorescent fibers. The former can be seen with the naked eye on the paper surface; the latter and the colored dots must be visible under the ultraviolet irradiation, and the colors are red, blue, orange, etc. The shape can be thick or thin, can be long or short, depending on the design . Some fibers are scattered on the paper before it is formed. The position of the fiber and the color point in the paper are generally randomly distributed, so the density and the number of the dew point are different. There are also fixed positions, such as the U.S. dollar printed before 1928. Red and blue fibers are distributed only in a narrow area in the middle of the ticket.
Fibers in foreign banknote banknotes such as Swiss francs, Austrian shillings, and Dutch guilders are colored with fluorescent light under ultraviolet irradiation. The fibers embedded in the paper can be picked up with needles, and the false fibers on the printed paper are of course nothing. Although the fibers pressed on the surface of the paper can be singled out, it can be seen under the stereo microscope that the fibers are only embedded on the surface of the paper instead of being embedded in the pulp.
In recent years, metal moorings and plastic circular tablets have been incorporated into the pulp to prevent counterfeiting. In foreign countries, there is also a flat polyester-encrypted paper with characters printed on polyester yarn. These characters can only be seen when light is observed in a certain direction, cannot be copied with a copying machine, and the anti-counterfeiting performance is good. An Italian-issued banknote has a metal mooring that is not visible to the naked eye and emits a sound when examined with a special identifier.
It has been reported that the United Kingdom is researching the use of a special kind of fiber to spread a small piece, then illuminating it with a specific light source from a certain angle, obtaining a stereoscopic projection, storing it in a computer, and then authenticating the authenticity through the projection of the mark.
Oak Ridge National Laboratory developed a two-color fluorescent fiber paper cryptography. The two-color fluorescent fibers are added to currency, licenses, and credit cards to produce optical features. This added optical feature is randomly distributed and includes multiple variables such as vertical, horizontal orientation, and fluorescence intensity. According to the inventors' estimation, the probability of random replication duplication for a density of 12 fibers per square inch is 10-1000, which is almost impossible to duplicate. This method requires pre-recording and checking of data. It is easy to use when used.

6 Security thread. In the papermaking process, special metal wires or polyester plastic wires, microprinting wires, and fluorescent wires of different colors are embedded in specific positions on the paper. A complete or intermittent (windowed) line is observed in the light and buried in the paper base. Line shape can be straight, wavy, zigzag and so on.
As early as the beginning of 1930, Stanley Chamberlain, general manager of the Bank of England’s banknote printing plant, worked with Porter to test the security line in the banknotes. It was also called the Chamberlain Line. Prior to this, the security thread was used for some other documents. The texture of the security thread must be very flexible, fold-resistant, non-breakable and able to adapt to high-speed paper machines. The security line was quickly recognized as a method of public identification. This line won the first patent after 1935. This line of security was first applied to the one-pound banknote issued by the Bank of England on March 29, 1940. Many of the subsequent banknotes used the Chamberlain line. For decades, with the advancement of technology and improvement of craftsmanship, on March 20, 1981, on the newly issued 50-pound bill, a contour line was formed along the edge of the ticket with a security thread, and the process became more complicated, which was conducive to security. This new security contour was produced on equipment developed by the Bank of England in cooperation with the United Kingdom Agency, and the silhouette was fabricated using programmed laser beams.
The emergence of color copiers provided convenient conditions for the manufacture of counterfeit money. To this end, the Bank of England introduced an improved safety line. This new security thread segmentation interval is exposed on the face of the ticket, and the color of the exposed metal line will become a black broken line. Later, the production method of the security line was improved. In 1970, the banknote printing plant launched a window security line called "cosmic dust", which was used for the 20-pound ticket issued that year. Due to the great success of "Cosmic Dust", it is now used on 10 pound notes and exported to Malaysia, Turkey and Sri Lanka.
In France, the Czech Republic and China's newly designed passport samples, there are also different types of security threads, including invisible monochromatic or two-color fluorescent, on the inner pages of paper. Some of the security lines also have miniature printed text. The exposed part of the window security line is silvery white, and some of the above are also microtext, you can see with a magnifying glass, and some of the naked eye can also be seen.
The security thread with microtext is a flat polyester thread that is visible through the light but cannot be copied. In 1996, the new version of the hundred-dollar bill had a polymer anti-counterfeiting security thread set in place, and had red fluorescence under ultraviolet irradiation. The word "USA100" is also printed on the security line that passes through the ticket vertically.
In recent years, there has been introduced a heat-sensitive security line, a line of pink opaque at room temperature, when the local heating with a finger to reach the body temperature of 37 °C, the local part of the display of micro-printing text. There is also a security thread that distributes color changes due to different viewing angles. Laser holographic security lines not only change the color but also transform the image. A type of metal or magnetic security that can be detected with the appropriate controller to emit a specific signal or sound.

7 Anti-copy paper. In order to prevent counterfeiters from copying currency or confidential documents, there are two kinds of anti-copying methods in foreign countries. One is that the copying machine is installed with the automatic copying registration device before leaving the factory; the other is the anti-copying paper. A full-absorption anti-copy paper has a blue or brown-red appearance. Only the light on the paper can be seen through the light, and the copy is dark. This kind of paper is not convenient for daily use, so it is difficult to popularize and apply. The other is to coat the surface of paper with a thin aluminum protective layer, but it does not affect printing. Because the aluminum protective layer can spread or deflect the light of the copier, the copy will appear black.
Fraser Labels develops a substance that can cope with color copying. When a brand or other sample is copied by a color copying machine or scanned by a scanner, it clearly produces the word "VOID" printed in black and white. This VOID logo can be used to seal CDROM cover, computer software, cosmetics and other packaging.
There is also a new type of anti-counterfeit paper similar to a plastic photo, which can be written, printed or typed by ordinary methods. However, words printed or written cannot be completely erased or altered, nor can they be copied.