Modern flexographic printing presses are equipped with an anilox roller / scraper combination ink supply system. Due to the special mesh structure of the anilox roller, the printing plate can obtain the required amount and accurate inking volume. The flexo industry can use different ink supply systems and substrates. Flexo printing machines come in many different printing sizes, from 200mm to 300mm narrow-format trademark printing to 4m wide-format printing. An independent doctor blade system is generally used on narrow-format flexo printing machines, and a cavity doctor blade system is generally equipped on medium-sized and wide-format flexo printing machines. Independent Scraper System Cavity Scraper System Depending on the size of the press width, the printing speed can reach 50 m / min to 450 m / min. Flexo printing is an indirect printing method, the ink is transferred to the substrate through the anilox roller and plate cylinder. The anilox roller controls the amount of inking through the number of screen lines and the volume of the hole. When the squeegee blade scrapes ink, always control the reverse angle between 30 ° and 40 °. For high-viscosity inks, such as UV inks, it is recommended to increase the angle to between 40 ° and 45 ° (pay attention to whether the scraper shakes). The pressure of the blade will change the amount of ink transfer. When the pressure is lighter or the edge of the blade is thicker, the amount of ink will increase, otherwise the amount of ink will decrease. However, it is best to adjust the ink viscosity by adjusting the amount of ink on the ink. The pressure of the blade must be as light as possible. In addition, the cell structure (outline arrangement / number) and the thickness of the blade edge are equally important for the life of the blade. Some engraved mesh walls are horizontal to the edge of the blade, which can cause additional wear of the blade or jitter of the blade. When using an anilox roller with a low thread count (large opening), a knife edge that is too thin will scrape away more ink from the mesh hole, resulting in insufficient printing ink. Anilox rolls with a lower thread count, a rough surface of the cylinder, and the use of granular inks (such as white ink) will accelerate blade wear. MDC's Soft blades (nickel-plated blades) have successfully extended the life of the blades in use. Its characteristic is that the nickel plating on the surface of the blade reduces the wear between the blade and the anilox roller. In most cases, the blade life is increased by 2-3 times. Due to reduced blade wear, less worn metal particles fall into the ink system. This correspondingly certainly reduces the damage to the anilox roller surface. For higher viscosity inks (UV inks) or granular inks (metallic inks, white inks), it is recommended to use MDC coated Longlife blades (black swords). This kind of blade can theoretically increase the life of more than 10 times, of course, this is also related to the status of the printing press and ink. But it can effectively solve common problems in printing. It is especially suitable for printing on full-field solid and spot color inks such as black, white, red, blue, green, gold and silver. Flexographic printing mainly uses 0.20mm thick blades. If the wide-format printing machine is equipped with an independent doctor blade system, generally 0.20mm to 0.40mm thick liner blades should be used (pay attention to whether the doctor blade jitters). In the cavity type blade holder system, there is no need to use a liner blade, but the blade generally needs to be exposed between 8mm and 15mm. According to the application requirements and the anilox roller screen selected, blades with different edge thicknesses or blades with traditional oblique blades can control the amount of ink. In the trademark printing layered version, a blade with a thickness of 0.065 mm to 0.085 mm should be used. Most printers generally use a blade with a thickness of 0.085 mm to 0.125 mm. As a rule, use a thin blade to wipe the ink cleanly. However, when choosing the correct blade edge, it is necessary to consider the corresponding different anilox roller lines. In general, MDC doctor blades are used for flexographic printing on ceramic anilox rollers. The greater the viscosity of the ink or varnish, the greater the blade pressure. This causes increased wear on the blade and anilox roller. On some special anilox rollers, the blade wear is even greater. To extend the life of anilox rollers and blades, 0.20mm thick MDC Longlife (black treasure knife) and MDC Soft (nickel-plated blade) are commonly used. Pp Personalised Mailing Bags ,Pp Compostable Postage Bags ,Pp Clothes Shipping Bags,Pp Compostable Shipping Bags DongGuan Sengtor Plastics Products Co., Ltd. , https://www.sentebio.com
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