The most popular variety of anti-counterfeiting pa

2022-08-05
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All kinds of anti-counterfeiting paper

I Watermark paper

is a paper with relief, perspective, touchable image, bar code, etc. Banknotes use watermark anti-counterfeiting technology. Because the watermark can not be reproduced by copier and scanner, its anti-counterfeiting effect is highly valued. Nowadays, the application of watermarking has been extended to valuable bills, certificates, and even books and periodicals. In the process of papermaking, the watermark is made by using technology to put the required logo and image into the paper. The team manager of Sumitomo Chemical Co., Ltd., who is responsible for relevant research, Lida Hara also worked hard to put the 10 foot case into the paper. For example, the watermark graphic plate designed in advance is installed on the silk, or it is pressed through the printing cylinder. Due to the different height of the picture and text, the paper pulp forms the corresponding density of different thickness. After the paper is finished, due to the different density of the paper pulp at the picture and text, the transmittance is different. Therefore, the original design picture and text can be displayed during the light transmission observation

there are three kinds of watermarks: fixed watermark, semi fixed watermark and unfixed watermark. The printing process of fixing the watermark is very difficult. It must be fixed at a certain position of the main body such as banknotes, passports, certificates, etc., and usually must be matched accurately with the printed graphics and text visible to the naked eye or other anti-counterfeiting measures. For example, there is a fixed watermark of Mao Zedong's portrait at the watermark window for RMB 100. The distance and position between each group of semi fixed watermarks are fixed, and each group is arranged continuously on the paper. Therefore, it is also called manager watermarks that successively resign from state-owned instrument enterprises to foreign-funded enterprises or go overseas to establish private enterprises. It is mostly used for special paper. The unfixed watermark is distributed on the full page of the paper or face, so it is also called full page watermark. For example, the five yuan, two yuan and one yuan of the third and fourth sets of Chinese coins are all printed on the full page ancient coin watermark paper, but the new five yuan has been printed on the daffodil pattern fixed watermark paper

1. The anti-counterfeiting watermark paper has developed from the original long paper to today's highly secure long paper. Its characteristics include:

2. Up to 15 gray levels can be obtained, so there are many levels; The thickness of black water printing area can reach 40 μ, Specific average thickness 15~20 μ The paper is thicker, so it has better contrast; And have good details and watermark definition

3. Additional safety measures not available for long paper, such as safety line, can be obtained

4. Add long cotton fiber into wood pulp to improve the service life of paper. On the circular paper machine, the watermark is formed on the surface of the watermark through fiber accumulation. The watermark is formed at the same time with the paper, which means that the watermark can be filled into the peaks and valleys of the circular mold to form a very clear watermark

with the development of electronic technology, electronic watermark paper has been launched. According to the times in May, 1999, a system called "microbar" uses chaos theory to encode data into a password and add it to the document background. This "microbus" is invisible to the naked eye, but can be read by a scanner to crack its password. Only the original printing plate can be printed. Any precision printing equipment cannot copy or can only print some ambiguous images. According to the development company, it is almost impossible to decipher the "microbar" coding system from a mathematical point of view

II Anti counterfeiting paper with safety thread

refers to placing a gold thread or plastic thread in the middle of the paper during the papermaking process. Special metal wires were first used. Now polyester plastic wires, miniature letter safety wires, fluorescent safety wires, etc. are used. The shape of safety line includes straight line, wavy shape, sawtooth shape, etc. According to relevant information, the new US dollar bill not only embeds metal wires in the paper, but also reduces the text that can only be seen with a high-power magnifying glass. In recent years, the thermal safety wire has been introduced. It is pink and opaque at room temperature. When the finger is used to heat the local part, as long as it reaches 37 ℃, the local micro printed text will appear. There is also a kind of safety line - laser holographic safety line. The color changes due to different viewing angles

put safety wires in the paper. The width of the wires can be as small as 1mm. If multiple safety wires are placed at the same time, the distance between the wires can be as small as 4mm. It can safely print the patterns and words required by users. According to the different difficulty requirements of anti-counterfeiting, the printed patterns and words can be made into hollow or non hollow

the safety wire in banknote printing is also the focus of research in various countries: for example, the United Kingdom adopts the windowed transmission safety wire, France develops some safety wires with aluminum plating process, Finland adopts the fluorescent safety wire, etc. Biochemical anti-counterfeiting marks are a major breakthrough in the development of anti-counterfeiting technology. Recently, foreign biological research institutions have successfully developed them. They mainly print secret marks on self-adhesive marks to achieve the purpose of anti-counterfeiting. Digital Deformation anti-counterfeiting technology has also been applied in foreign countries. This technology is applicable to any printed matter that needs Arabic numerals. Deformation is realized by computer without any rules to follow. Recognition is also through computer

III Laser anti-counterfeiting paper

laser anti-counterfeiting technology is combined with paper to make anti-counterfeiting paper. For example, the holographic anti-counterfeiting technology and special equipment are used to make the holographic image at the specific position of the banknote to improve the anti-counterfeiting performance. Its characteristics are as follows:

1. Because the holographic pattern is made directly on the paper, the plastic information layer is removed, so it is rarely possible to be copied

2. The patterns on the paper can be designed, plate made and produced according to the requirements of the business, with different textures and grams of paper (70~400 grams), such as coated paper, cardboard and paperboard, and can also be offset printed and silk screen printed like ordinary paper

3. In the later stage, the billet will meet the test of production restriction. It is only slightly more expensive than ordinary composite gold and silver cardboard, which is equivalent to 10% of the price of holographic anti-counterfeiting trademark, and saves the labor cost of labeling, so it is easy to be accepted by merchants

4. After being discarded, it can be weathered in the soil without polluting the environment

at present, laser anti-counterfeiting paper has played a role in the packaging and printing of some cigarettes, wine, cosmetics, food, etc. For example, Shengli Oilfield aluminum foil composite material factory recently produced a kind of film-free holographic dark anti-counterfeiting printing packaging paper. It has the characteristics of full version anti-counterfeiting before and after printing, and the whole paper can be designed and made into a special version or a common version of laser anti-counterfeiting image, with a width of more than 800 mm. The pattern adopts implicit design, which can be seen clearly even if it is covered with multi-layer ink. It has excellent light refraction effect and does not affect the design and printing theme

IV Red and blue fiber silk and color dot encrypting paper

when making paper, colored fibers such as red and blue or colored small pieces (dots) are mixed into the paper pulp, or scattered on the paper surface before the paper is finalized, and there is fluorescence reflection under ultraviolet radiation, so that the finished paper has colored fibers different from the paper itself. There are two kinds of red and blue fibers and colored dots mixed into pulp, namely, colored fibers and colorless fluorescent fibers. The former can be seen on the paper with the naked eye, while the latter and color dots must be visible under ultraviolet radiation. The colors include red, blue, orange, etc. the shape can be coarse or fine, long or short. The fibers and color dots are generally randomly distributed, so the density is different. In addition to plant fiber, in recent years, there are also anti-counterfeiting methods that add metal foil and plastic round pieces into pulp. For example, a metal foil invisible to the naked eye is sandwiched on the paper currency issued in Italy, which will make a sound when checked with a special identifier. In addition, the British research uses a special fiber to lay a small piece, and then irradiates it from a specific angle with a specific light source to obtain a three-dimensional projection, which is stored in the computer, and then the authenticity of the projection of this mark is verified

v Copy proof paper

a kind of full absorption copy proof paper, which is blue and brownish red outside. The pictures and pictures on the paper can be seen only through light, and the copies are dark. But this kind of paper is not convenient for daily use. The other is to apply a thin aluminum protective layer on the surface of the paper (but it does not affect the printing). Because the aluminum protective layer can disperse or deflect the light of the copier, the copy is black. In addition, some anti copy paper will show words such as "copy" and "invalid" after copying, which can effectively prevent color copying of important documents. In addition, there are also anti copy papers that will change color or show hidden words when they encounter the light of the copier. For example, Fraser labels has developed a substance to deal with color copying. When samples such as trademarks are copied with a color copier or scanned with a scanner, the word 'void' will be clearly generated, and the logo will be printed in black and white

VI Paper with trace additives

uses the principle that biology has a specific reaction with antigenic antibodies to add a very small amount of antigenic antibodies to a part of pulp or paper. During the detection, the corresponding specific antibody is used to combine with it, and the authenticity can be identified through the presence or absence of color, fluorescence and other marker reactions

VII Chemical encrypting paper

special compounds are added to the pulp or when sizing the paper surface. This kind of chemical encrypting paper can develop color or fluorescence when coated with specific chemical reagents. Tickets for a foreign football match are printed on this paper. When checking, just take a pen dipped in a special reagent and draw it on the ticket. The crossed part will show black

VIII Ion medium special anti-counterfeiting paper relying on the large-scale heavy ion accelerator specially controlled by the state, the super energy ion medium special anti-counterfeiting paper, which integrates the ion micropore technology and papermaking technology, solves the long-term problem of anti-counterfeiting and identification of effective certificates

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