2. Strengthen the anti-counterfeiting of ink: ink is one of the main components in banknote printing. The fourth set of RMB uses a variety of anti-counterfeiting inks, such as colorless fluorescent ink, metameric ink and magnetic ink. Colorless fluorescent ink: ink that has no color but can emit bright fluorescence under ultraviolet irradiation. For example, 1990 edition 100 yuan and 50 yuan coupons are printed with Arabic numerals and Chinese pinyin denominations in this ink, and yellow fluorescence can be clearly seen under ultraviolet light.
Magnetic ink: special instruments are needed for testing. This ink is used for the figures of the fourth set of RMB coupons, and the deep lace on the front and back of 50 yuan and 100 RMB coupons.
3. Strengthen anti-counterfeiting in plate-making printing technology: The fourth set of RMB mainly adopts hand-carved intaglio printing, intaglio printing wiring technology, overprint printing technology and relief printing wiring technology, which greatly improves the anti-counterfeiting function of RMB. Hand-carved intaglio printing technology has always been an important means of banknote anti-counterfeiting in the world. Its main characteristics are thick ink layer, strong hand feeling and difficult to copy.
4. Security line: Embedding security line in banknote paper is also the main measure of RMB anti-counterfeiting. Safety thread is a kind of thin wire made of metal, which is magnetic through instrument detection. 1990 edition 100 yuan, 50 yuan coupons were added with metal safety thread, which was added during papermaking and buried in banknote paper, not directly printed on the face. With the naked eye, you can see that the safety line runs through banknote paper on the right side of the ticket.
5. Digital anti-counterfeiting: 1980 RMB, using thin-line digital anti-counterfeiting.
6. Anti-counterfeiting without intertexture: The fourth set of RMB also adopts intertexture. For example, 1 yuan, 2 yuan and 5 yuan banknotes have flower patterns in the lower left corner; At the same time, there is a similar pattern in the lower right corner of its back. Looking at the banknotes under the light, we can find that the two patterns are completely coincident. Although this anti-counterfeiting measure was not made public at that time, it was strengthened in the fifth set of RMB (complementary pattern of yin and yang) and became one of the public anti-counterfeiting measures.
Baidu Encyclopedia-4th Edition RMB