Bills can be said to be one of the most
closely related printed materials in people's daily life. From the commonly
used banknotes, bonds, industrial and commercial tax invoices, stocks, cheques,
securities, stamps and tickets for various activities, it directly involves
personal interests. Bill is not only a voucher, but also has its special
collection value in the collection market. With the development of high-quality
image input and output equipment, especially the emergence of high-precision
color inkjet, laser printer and high-precision color copier, the China printing operator can conveniently cut and splice
digital information, adjust brightness, contrast and color, and add and change
background and text, which makes the forgery of check and other bills more
easy. Traditional anti-counterfeiting technology has been unable to meet the
demand, in order to prevent such risks, the bill in the design and production
of anti-counterfeiting technology put forward higher level requirements.
The new anti-counterfeiting technology must
be unique, which makes the corresponding technology can not be obtained from
other places; moreover, it is required that the technology is difficult to
forge. Digital watermarking technology is an effective method, it is an
important research direction of information hiding technology. Digital watermarking
technology will not change the visual image of the bill, which can satisfy the
bill design experts to give full play to their creativity. At the same time, it
has the world's most advanced, safest and most advanced anti-counterfeiting
standards.
1� The status quo of
anti counterfeiting of bills
Our country's bill anti-counterfeiting
printing technology involves many scientific fields, such as optics, chemistry,
electromagnetics, computer technology, spectrum technology, text code
technology, etc., which belongs to a cross edge science. At present, there are
several anti-counterfeiting technologies:
� Paper anti counterfeiting: with the rapid development of China's
paper technology, paper with anti-counterfeiting function has been continuously
applied to the production of bills, such as: watermark, visible fiber and
invisible fiber, safety wire paper, etc., these are some of the more common
anti-counterfeiting technologies that are widely used. In addition, there are
anti-counterfeiting paper. When we identify these technologies, some are naked
eyes What can be seen directly, some are carried out by instruments, while
others are identified by comprehensive means. These are the first-line
anti-counterfeiting, second-line anti-counterfeiting and third-line
anti-counterfeiting.
� Anti counterfeiting ink: in bill printing, anti-counterfeiting inks
can be divided into colored fluorescence, colorless fluorescence, infrared ink,
photochromism, temperature change, anti erasure, drip disappeared ink, etc.
these inks use different identification features to form different
anti-counterfeiting schemes. The above-mentioned first-line, second-line and
third-line are used for anti-counterfeiting.
� Plate making and anti-counterfeiting: plate making anti-counterfeiting
is the application of some professional software to design some
anti-counterfeiting shading, which is difficult to copy to a certain extent.
From this point to achieve the purpose of anti-counterfeiting, the more common
are: tuanhua, microfilm, latent image, unlocking, variable line width, etc. the
anti-counterfeiting of shading is based on the lines, which can produce rich
changes and prevent forgery Scanning increases the added value of the bill. Of
course, when designing and outputting anti-counterfeiting shading, the computer
is required to be high. At present, it is a relatively extensive
anti-counterfeiting means, mainly used in certificates, certificates,
securities, etc.
� Comprehensive anti-counterfeiting: in the field of bill printing,
the most common anti-counterfeiting technology is the combination of
anti-counterfeiting paper, anti-counterfeiting ink and plate making
anti-counterfeiting. The comprehensive anti-counterfeiting technology combines
the advantages of three anti-counterfeiting means, which brings great
difficulties to forgery. Of course, its added value is also higher.
� Anti counterfeiting holographic logo positioning hot stamping
technology. Positioning hot stamping technology is very difficult, it requires China printing manufacturers to have
precision positioning hot stamping equipment, in the hot stamping label can use
all the general holographic anti-counterfeiting technology, such as pixel
holography, true color synthesis encryption micro lithography photolithography
and other technologies, which can play an excellent anti-counterfeiting effect.
� Rainbow printing anti-counterfeiting technology. Using rainbow
printing anti-counterfeiting technology, according to the bill printing
requirements, it can print a variety of colors at a time, and the intermediate
color transition is soft. It is difficult to realize the rainbow printing
effect by multi-color overprint, and it is difficult to see the exact position
of each color separator in the ink fountain in the bill. Even if the
counterfeiter imitates the rainbow printing method, it is difficult to determine
the spacing between the separators, thus increasing the difficulty of
counterfeiting.