Improve the quality of printing by improving the anilox roller technology

For the anilox roller, there have been many new developments. However, we can only see the good results brought about by this new change if we only make fundamental adjustments to the printing process.

Flexographic printers all want their own advantages. Printers and accessories manufacturers have also been advocating the power of their new technology improvements. But if we do not pay attention to the basics, all these new technologies will not bring us imaginary results.

Let's explain what is the basic work, that is, under what circumstances does the system need fine tuning?

- When using a rubber nip rill instead of a squeegee, this technique does not precisely control the thickness of the ink layer on the anilox roller.

- When the pH or the viscosity of the ink (the two key factors affecting ink flowability) are not monitored, the color density shifts.

- When the gears of the gears used are worn out, this can lead to unstable ink transfer.

- The bearing becomes loose or worn, and the pressure between the dust plates is also unstable.

- The phenomenon of elongation and deformation of the flexo due to repeated loading and unloading.

——We cannot think that an 800lpi anilox roll with 200 billion cubic micron meshes formed at a 60-degree angle will produce the same ink transfer performance as the 120-millimeter micron anilox roll formed at a 30-degree angle. .

- The damaged and blocked anilox roller, with its ink transfer performance and clean and well-oiled anilox roller, will have different ink transfer performance even under the same engraving data.

All process variables must be correct, so that when we use new technologies, we can see the advantages brought by new technologies. Moreover, the requirements for printing quality must be related to the cost and workload, otherwise there will be situations where the staff insists on their past experience.

FM network technology and hybrid screen technology (to use the traditional width screen with FM for a wide range of applications also requires a long process, so the traditional screening technology still occupies a large proportion when it is used. It is somewhat premature to consider the use of FM networks, but if printers can consciously and systematically use new technologies, they will have a great advantage in the future competition.

Anilox manufacturers are always trying their best to develop higher number of engraving rollers. When the number of screens on the user's screen reaches more than 150 lpi (even more than 200 lpi), the minimum number of anilox roller lines established has reached 800 lpi, and it is recommended that if 1000, 1100, and 1200 lpi anilox rollers are used, better results can be obtained. .

For 20 years, 800 lpi has been the limit of laser technology and control technology. It was only in the past few months that the limit of the number of engraving lines was exceeded.

The benefits of the new engraving technology are quite obvious. The higher number of engraving rollers can support smaller, brighter versions of the Internet, reducing the occurrence of dipping (this type of dipping, which means that the dots are smaller than the anilox roller At the time, it will be completely immersed in the mesh, which will cause the phenomenon of ink sticking around the dots, resulting in the unclear layout and the phenomenon of large dot gain.)

Although anilox roller production can currently produce more than 2000 lpi, few people purchase more than 1,500 lpi anilox rollers. This kind of anilox roller over 1500 lpi, the mesh slot is very small, and the net wall is very thin. Although this kind of mesh can achieve high printing quality, it is difficult to support the currently used cleaning methods such as ultrasonics and soda jets because of the fine mesh wall structure.

In addition to the consideration of clean destruction issues, most printers only need to meet the user's requirements without having to reach the number of such people.

In general, users who use 1500 lpi mesh rollers are also rare. The trend of increasing demand is between 900 and 1200 lpi. However, this range of orders are all from high-quality print jobs in the printing industry, mainly for narrow, medium and wide web presses. If it is necessary to use more than 800 lpi anilox, the optimization of the components of each ink delivery system must be a key factor.

CO2 lasers have been the standard laser generator used for engraving in the industry for many years. YAG lasers are also very good at producing fine engraving effects, because their beam is narrower and can be focused on even finer points; their energy is more concentrated and a cleaner mesh can be obtained with finer mesh walls. . The laser's basic engraving capability is 1200 Lpi; while the CO2 laser's ability is at 700 lpi. Therefore, if the required ink dot is finer, this laser product can obtain a better color tone effect.

If the engraving technology is not considered, the thickness of the net wall will decrease more and more with the increase of the reticulate lines. If the 400 lpi wall is twice as thick as 800 lpi, the service life of the 400 lpi anilox roll will be longer and the use requirement will be lower.

For printers who want to use offset printing to obtain offset quality, setting up standards and monitoring variables is an important part. The standards of the printing process include the amount of anilox ink and the prescription of the reticulation angle for each thread number.

The interchangeability and estimation of the system must be strictly controlled. Once control is established, the integrity of the system is maintained. This is to properly maintain the components of the press. If this is done, we will notice a noticeable change in the quality of the printing, and the work done is only the basics and the control of the printing process.