Q & A on the basics of flexography 1

Q & A on basic knowledge of flexography 1

1 What is flexographic printing

answer: flexographic printing, as a special embossing method, was originally called "aniline printing", and its initial name came from the volatile liquid ink made of aniline dye when it was produced. With the progress of science and technology, aniline inks with bright colors but easy to fade are no longer used, so the name "aniline printing" has no practical significance. On October 21, 1952, the 14th Symposium of the American Packaging Society officially named this printing method as "flexography", which means flexible printing plate, The term "flexographic printing, whether made of metal or non-metal materials" was also introduced into China shortly afterwards

in 1980, the American flexographic printing China Plastics Machine Development Association officially defined flexographic printing as: flexographic printing is a direct rotary printing method, which uses an elastic convex image printing plate, and the printing plate can be bonded to a printing plate of repeatable length. The new mobike (internal code "Feng Qingyang") launched in April adopts Dow polyurethane material - polyurethane solid wheel barrel, The printing plate is inked by a metal ink roller engraved with ink holes. The metal ink roller (grain transfer ink roller) is controlled by another ink roller or doctor blade to transfer liquid and grease inks to all kinds of materials

the definition of the terminology GB 9851.4-90 in China's printing technology standard: flexographic printing is a printing method in which flexographic plates are used and ink is transferred through corrugated rollers

2. When and where did flexography begin to be applied

answer: no one can say exactly when the flexo was officially used. Some data say it originated from Germany, and some data say it originated from Britain in 1890. However, it is actually recognized that the first aniline printing machine was developed by British Howe in 1905. This invention was granted British patent No. 16519 on December 7, 1908

3. What is the structure of flexographic printing machine

answer: flexographic printing machine is mainly composed of inking unit, printing plate and embossing cylinder. The figure shows the structural diagram of the two most common flexographs (the difference mainly lies in the ink supply system of flexographic). The black-and-white pictures are three roller inking system, and the color pictures are cavity doctor blade inking system

4. What are the differences between flexographic printing and other relief printing

answer: ① ink is a low viscosity volatile dry ink with alcohol as the main solvent. It has fast drying speed and is suitable for high-speed and multi-color flexo printing. The application of pollution-free and fast drying water-based ink is very beneficial to environmental protection

② flexible plate is a kind of photosensitive rubber. With the improvement of domestic technology and the demand for large-scale printing plate, it is soft, flexible and elastic. Shore hardness is generally, and it has good transmission performance for inks, especially for alcohol solvent inks. This is unparalleled by plastic and photopolymer lead plates with a shore hardness of more than 75

③ light printing pressure is used for printing, which is called Kess print (as gentle as kissing) in foreign countries

④ there are a wide range of substrate materials for flexographic printing

⑤ good printing quality. Due to the use of high-quality resin plates, ceramic rollers and other materials, the printing accuracy has reached 175 lines, and the level is also very full

⑥ high production efficiency. Flexographic printing equipment itself is fast, plus it usually has the function of multi-color group and online multi process operation

⑦ simple operation and maintenance. Including the operation of the previous version, maintenance, ink, etc. have become very simple. (to be continued)