FM network with micro-scale dot size performance, in the single-cassette rotary printing, generally up to 21 ~ 25 microns, the use of ink and color reflectance than 133 ~ 200lpi of the AM screening is better, such as 21 micron FM plus The details represented by the net are equivalent to 400 lpi, which can effectively reduce the color pollution from the paper.
4) The copying effect is good. The copying of the FM network is the best for the middle tone level, and it can eliminate the tone shift of the middle tone, so that the tone transition is natural and harmonious. In addition, its color transition is delicate, which is conducive to ultra-four-color printing, and color separation films can be recorded with lower resolution.
5) Better visual stability When the AM screening is not accurate, the visual mesh structure will change. FM screening will not change whether or not the version is inaccurate. The printers also found that the FM network can better represent the details of the prints when the printing plate is not accurate. In terms of color stability, when the amplitude modulation screen is misaligned or the web offsets slightly, the hue and color will shift, and the FM network will not have this problem.
6) Not restricted by the screen angle In the AM screening and screening technology, various parameters such as the number of meshes, screen angle, and net shape are very important, and the technical personnel must understand. FM has only one parameter of network size, so its control technology is quite easy. FM screening is not performed according to the fixed screening angle and grid. Therefore, the screening screen has no direction and is not limited by the screen angle. The variable distance between the network points is not fixed, and there is no network cable number. Special conditions for creating special reproductions, such as metallic color, jewellery, color, Chinese painting, etc., can also be achieved by printing four or more colors, expanding the range of color reproduction of printed materials, and performing high fidelity copy printing.
7) Avoiding mis-networks Mis-networking is the enemy of the color plate making industry for a long time. There is no rule in the distribution of FM-screened networks, and there is no misplaced network with multiple color plates. Even if textiles in prints or manuscripts are copied, there will not be any mis-networks. In addition, the FM network is insensitive to overprinting errors in the process of printing platemaking, while the traditional AM dots may be misplaced due to overprinting errors.
8) The printing effect is better Firstly, it prints faster on the printing machine without adjustment, the ink drying time is shortened, the working time is reduced correspondingly, the ink and ink balance is easier to maintain, and the thicker ink coverage can obtain a higher dynamic range. Thinner inks are more evenly distributed. In multi-color overprinting, the problem of registration does not affect the color balance, and the color version of the screen plus the overprint of the primary color version does not appear to have a moiré pattern.
Third, the improvement of FM screening technology However, FM screening itself is not perfect, there are also deficiencies, such as:
1) Due to the equal size of the dots, there is a graininess, especially in the high-light part and the tone of about 25% is more obvious;
2) The latitude of the entire production process is smaller than that of the amplitude modulation screening. Therefore, a more detailed process control and monitoring technology than the amplitude modulation screening is required. For example, the latitude of the FM screening deviation is small, and many changes in the film and development processing are made. The result is not significant; operators will have to adopt new levels of accuracy throughout the production process;
3) Because the effect of increasing the ink film thickness on the size of the FM network is not as significant as that of the AM network, it is difficult to improve the quality of the image with poor color separation by adjusting the ink on the printing press.
4) The smallest micro-dot size is too small to allow many printers to reproduce correctly;
5) At present, FM screening images still have some difficulties in proofing, copying, printing, etc., which will seriously hinder the film combination;
6) At present, the difficulty of image formation on the printing plate by the FM network is still relatively large, and it is also unstable. As long as any change occurs in the traditional platemaking process, it will affect the final tuning of FM screening and reduce the reliability of screening.
The above problems can be regarded as one of the major aspects affecting the popularity of FM screening technology. In addition, the AM screening technology has been continuously improved for more than 100 years and is now familiar to people and has its own advantages. As computer direct plate making and flexible and stable digital proofing technology are gradually promoted in the printing system, it will inevitably greatly reduce the variable factors that affect FM screening and make it embark on an extensive and practical road. This technology is used in sheetfed and rotating, packaging, magazine printing and other fields. As with other printing technology innovations, FM networks must constantly improve and improve software and hardware technologies, as well as corresponding training, testing, and other supporting facilities. We must also establish a sound production control system. To be sure, FM screening cannot completely replace AM screening at present and in the coming years. A new technology can only replace traditional technologies unless it has absolute advantages in all aspects. FM screening technology has not yet reached this level.
4) The copying effect is good. The copying of the FM network is the best for the middle tone level, and it can eliminate the tone shift of the middle tone, so that the tone transition is natural and harmonious. In addition, its color transition is delicate, which is conducive to ultra-four-color printing, and color separation films can be recorded with lower resolution.
5) Better visual stability When the AM screening is not accurate, the visual mesh structure will change. FM screening will not change whether or not the version is inaccurate. The printers also found that the FM network can better represent the details of the prints when the printing plate is not accurate. In terms of color stability, when the amplitude modulation screen is misaligned or the web offsets slightly, the hue and color will shift, and the FM network will not have this problem.
6) Not restricted by the screen angle In the AM screening and screening technology, various parameters such as the number of meshes, screen angle, and net shape are very important, and the technical personnel must understand. FM has only one parameter of network size, so its control technology is quite easy. FM screening is not performed according to the fixed screening angle and grid. Therefore, the screening screen has no direction and is not limited by the screen angle. The variable distance between the network points is not fixed, and there is no network cable number. Special conditions for creating special reproductions, such as metallic color, jewellery, color, Chinese painting, etc., can also be achieved by printing four or more colors, expanding the range of color reproduction of printed materials, and performing high fidelity copy printing.
7) Avoiding mis-networks Mis-networking is the enemy of the color plate making industry for a long time. There is no rule in the distribution of FM-screened networks, and there is no misplaced network with multiple color plates. Even if textiles in prints or manuscripts are copied, there will not be any mis-networks. In addition, the FM network is insensitive to overprinting errors in the process of printing platemaking, while the traditional AM dots may be misplaced due to overprinting errors.
8) The printing effect is better Firstly, it prints faster on the printing machine without adjustment, the ink drying time is shortened, the working time is reduced correspondingly, the ink and ink balance is easier to maintain, and the thicker ink coverage can obtain a higher dynamic range. Thinner inks are more evenly distributed. In multi-color overprinting, the problem of registration does not affect the color balance, and the color version of the screen plus the overprint of the primary color version does not appear to have a moiré pattern.
Third, the improvement of FM screening technology However, FM screening itself is not perfect, there are also deficiencies, such as:
1) Due to the equal size of the dots, there is a graininess, especially in the high-light part and the tone of about 25% is more obvious;
2) The latitude of the entire production process is smaller than that of the amplitude modulation screening. Therefore, a more detailed process control and monitoring technology than the amplitude modulation screening is required. For example, the latitude of the FM screening deviation is small, and many changes in the film and development processing are made. The result is not significant; operators will have to adopt new levels of accuracy throughout the production process;
3) Because the effect of increasing the ink film thickness on the size of the FM network is not as significant as that of the AM network, it is difficult to improve the quality of the image with poor color separation by adjusting the ink on the printing press.
4) The smallest micro-dot size is too small to allow many printers to reproduce correctly;
5) At present, FM screening images still have some difficulties in proofing, copying, printing, etc., which will seriously hinder the film combination;
6) At present, the difficulty of image formation on the printing plate by the FM network is still relatively large, and it is also unstable. As long as any change occurs in the traditional platemaking process, it will affect the final tuning of FM screening and reduce the reliability of screening.
The above problems can be regarded as one of the major aspects affecting the popularity of FM screening technology. In addition, the AM screening technology has been continuously improved for more than 100 years and is now familiar to people and has its own advantages. As computer direct plate making and flexible and stable digital proofing technology are gradually promoted in the printing system, it will inevitably greatly reduce the variable factors that affect FM screening and make it embark on an extensive and practical road. This technology is used in sheetfed and rotating, packaging, magazine printing and other fields. As with other printing technology innovations, FM networks must constantly improve and improve software and hardware technologies, as well as corresponding training, testing, and other supporting facilities. We must also establish a sound production control system. To be sure, FM screening cannot completely replace AM screening at present and in the coming years. A new technology can only replace traditional technologies unless it has absolute advantages in all aspects. FM screening technology has not yet reached this level.
Henan Hanchen Medical Technology Co., LTD , https://www.tchanchen.com