With the progress of society and the development of science and technology, some new high-tech initiatives have emerged in the printing of stamps. Such as: ultraviolet fluorescent ink, dual-wave invisible ultraviolet fluorescent ink, fluorescent encryption security ink, fluorescent coding, fluorescent fiber stamp paper and so on. All these should have standardized terms in the stamp collection field to avoid confusion.
First, ultraviolet fluorescent ink
UV fluorescent security ink is a kind of anti-counterfeiting ink in China. It is an ultraviolet-excited fluorescent ink that emits fluorescent ink in the visible light range under the excitation of 254mm or 365mm ultraviolet rays. Divided into colored fluorescent security ink and colorless fluorescent security ink. Colored fluorescent anti-counterfeiting inks are inks that excite fluorescent light by ultraviolet light containing pigments. In natural light, the color of their appearance is consistent with the fluorescence excited by ultraviolet light; colorless fluorescent anti-counterfeit inks are ultraviolet light that does not contain colorants. Fluorescent inks, under natural light stamps appear colorless or only extremely light colors. The first set of stamps printed in China using fluorescent anti-counterfeit inks was the “China-Japan Youth Friendly Galature†(1984) issued on September 24, 1984. The fluorescent security ink is yellow. Called yellow colored fluorescent security ink. The first set of stamps printed by the colorless fluorescent anti-counterfeit inks was “Qinghai Lake†on July 20, 2002. The white part around the perforations of the stamps emitted red fluorescence under ultraviolet excitation. Called a colorless red fluorescent security ink.
About "color-changing fluorescent security ink". The so-called "color change" is the color of a part of the stamp that is visually seen, but when exposed to an ultraviolet light, it shows another color of light. For example, "Hukou Waterfall in the Yellow River" is brownish-yellow when viewed intuitively, and red fluorescence under ultraviolet light. I thought it should be set as colored red fluorescent security ink. Because of the observation under the microscope, it can be seen that there are red dots in the brown-yellow area, that is, there is a red fluorescent anti-counterfeit ink, and red fluorescence is displayed. It is not brown to red fluorescence.
Second, dual-wave invisible ultraviolet fluorescent ink
Dual-wave is a fluorescent anti-fake ink with a dual wavelength of 365mm long ultraviolet ray and 254mm short-wave ultraviolet light. The stamp exhibits a color under the irradiation of a long wavelength ultraviolet ray of 365mm, and exhibits another color under the irradiation of a shortwave ultraviolet ray of 254mm. Compared with single-wavelength ink stamps, it has more security features. China's first set of double-wave invisible fluorescent anti-counterfeiting ink printed stamps, is the "Beidaihe" August 5, 2001, Henan Post and Telecommunications Printing Factory.
Third, fluorescence encryption security ink.
Encryption is in the fluorescent anti-counterfeit ink, adding a certain substance, in order to achieve the purpose of enhancing anti-counterfeiting ability, improving the level of light resistance, and extending the effective period. China's first set of stamps printed with fluorescent-encryption and anti-counterfeit inks is the “Spring Festival†sheetlet of the Beijing Stamp Factory on January 29, 2000.
Four, fluorescent inkjet
Fluorescent ink jet printing is the use of fluorescent ink jet stamps on the prefix and number. Its appearance has light-colored marks, and the head and number are composed of dots. Under ultraviolet light, the code emits fluorescence, which is the first in our country. The first set of stamps with fluorescent markings was the "Northern Song Dynasty. The Outstanding Deity" in the "Chinese Ceramics - Rong Kiln Porcelain" issued on April 8, 1999.