To judge the authenticity of stamps, there must be real evidence, not just feelings. The evidence we are talking about mainly includes six aspects, namely, stamp version, paper, color, ticket width, perforation and adhesive.
Edition: Stamp printing methods include engraving, offset printing, letterpress, photocopying and photocopying. At present, most fake stamps are printed by offset printing, but domestic stamps are rarely printed by offset printing, especially ordinary stamps issued in recent years. The biggest difference between a real stamp and a fake stamp is that the real stamp has a three-dimensional effect, the ink layer of the stamp pattern and inscription is raised, the feel is obvious, the pattern is clear, the pattern is solid, and the color is soft and uniform; However, the fake tickets have thick dots, distorted fonts, blurred patterns, overlapping colors and exposed colors.
Paper: Real stamps are made of "coated stamp paper" specially used by manufacturers designated by the postal department, without whitening agent. So under the purple light, special paper has no fluorescence reflection, while fake stamps have fluorescence reflection.
At present, in China, special paper with fluorescent fiber strips is used for stamp printing. Under the violet light, it can be seen that its density is uniform, while the fake stamp paper has no fluorescent fiber strips. Even if there are some fake stamps, their fluorescent fiber strips are different from real stamps in density and shape.
In addition, real stamps are obviously different from ordinary offset paper and coated paper in color. Careful observation from the surface of the paper can also distinguish the authenticity.
Brush color: the facial effect produced by stamp printing. Brush color is a comprehensive product of printing technology, paper, ink and other factors, mainly determined by ink. Real stamps use fluorescent ink, with positive tone and rich colors; However, because fake tickets are offset printed with ordinary ink, it is inevitable that the color is dim and the hue is not right, and there will be color overlap and red exposure caused by inaccurate color registration. When viewed through a magnifying glass of 20 times, patterns often show outstanding points.
Ticket width: measure the ticket width of stamps, which is mainly used to identify fake toothless stamps and fake toothed stamps. Some counterfeiters often cut off the tips of really toothed stamps and sell them as toothless tickets for profit. This requires philatelists to master the ticket width specifications that genuine toothless tickets should have, so as not to be deceived. In most cases, if it is a fake toothless ticket, you can observe the traces of tooth holes. Because the forger has to minimize the cut-off part in order to leave a wider margin as much as possible.
When identifying stamps with perforations, paying attention to the width of the stamps will also detect fake tickets. Because the size of most fake tickets is often inconsistent with the real ones, especially the perforation of forged sheetlets. It is inevitable for counterfeiters to make a special needle board when stamping sheetlets, with an error of 1-2mm.
Tooth hole: including tooth type, punching method and degree of tooth hole. The teeth of the stamp are stuffed with articles. Stamp printing equipment has strict technological standards, and the punched holes are regular, smooth and flat; But counterfeiters can't have the same technical conditions and can only make do with it. Visually, it can be seen that some fake tickets are triangular perforations, which are grooved and polygonal perforations under a magnifying glass.
Self-adhesive: Fake tickets generally have no self-adhesive, and some of them are painted with a layer of translucent white paint on the back of the ticket to pretend to be self-adhesive, but they are not sticky. Some are painted with glue, because the technology is so poor that even the perforated paper wool is stained with glue. For ordinary counterfeiters, it is not easy to apply glue evenly without deformation, but it is even more difficult to prepare glue with correct proportion and realistic color, so fake stamps often have no glue. Stamps that should be glued but not glued are particularly noteworthy.