The hottest violet laser CTP silver salt plate and

2022-10-23
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Purple laser CTP silver salt plate and ecological development (Part 1)

at drupa 2000 exhibition, the imaging of silver salt plate with inner drum purple laser CTP system attracted extensive attention. According to the manufacturer of violet laser CTP, the investment cost of violet laser CTP is significantly reduced compared with the outer drum thermal CTP with infrared diode

violet laser CTP was somewhat blocked in the early stage of entering the market, because there were few suitable printing plates for the system at that time. Although Agfa has launched a purple laser silver salt version, it can only be supplied in limited quantities. Later, Mitsubishi announced that it had launched a purple laser, realized a multi-purpose light plate with one machine, and designed an ecological plate washing machine, which completely reduced the use of chemicals and reduced the pollution discharge cost

Heidelberg prosetter 74 purple laser CTP

the applicability of silver digiplate alpha violet (SDP) printing plate has also been confirmed in Europe and has been successfully used in Backes druck printing plant. Since the end of 2001, the factory has used Heidelberg's prosetter74 violet laser CTP to image alpha violet plates and develop them on Mitsubishi's traditional plate punching machine. After the IPEX 2002 exhibition, the eco system was released for sale, and the factory began to use the modified p-alpha 880 super eco printing machine

Peter Backes, head of prepress at Backes druck printing house, and Klaus, head of printing business, pointed out that the view that it must take a lot of time and cost to master silver salt plate development is wrong. In the past, the developer often had sediment after shutdown on weekends, which not only required high cleaning costs, but also frequently changed the potion. Now, they use the p-alpha 880 super eco printing machine, and all the problems are solved

sdp alpha violet silver salt version

silver digiplate alpha violet version is produced by Mitsubishi company. The thickness of the base is 0.15, 0.20, 0.24, 0.30mm, and the base is anodized. There is a positive layer on the plate base, which is coated with silver halide emulsion. The sensitivity of this plate is 2 μ J/cm2, and the photosensitive wavelength is 410nm. Therefore, this kind of plate can be imaged with a purple laser diode with an output power of only 5MW and a light wavelength of 400 ~ 430nm

in the process of positive plate imaging, the hydrophilic part of the printing plate, that is, the non printing part (see Figure 1), is exposed. After chemical development, unexposed silver halide diffuses to the positive layer (physical development), and the exposed silver halide is washed away, followed by conventional gelatinization and drying. Developing solution, stabilizer and glue solution all contain chemical components that promote the ink absorption of printing plates

imaging: direct plate making machine exposure with violet laser diode light source produces latent image on the emulsion

development: the exposed silver ions react during development, and the unexposed part diffuses to the positive layer

fixing: the emulsion of non graphic part is brushed off during development. At the same time, pH neutralization is 7

gluing and printing: gluing is to prevent the oxidation of the printing plate. At the same time, optimize the ink absorption performance

the resolution of silver digiplate alpha violet version is very high, and 2% - 98% of the points can be well reproduced. The printing resistance of 120 lines/cm high-precision image version can reach 200000 prints, which is suitable for both ordinary inks and UV inks. In terms of press adjustment, there is little difference between using silver digiplate alpha violet version and using traditional PS version

p-alpha 880 super eco plate punching machine

the standard plate punching machine adopts the impregnation method. When the end of the printing plate is immersed, it is easy to cause the developer to overflow and make the target surface turbid. P-alpha 880 super eco plate punching machine does not use impregnation method, and the printing plate is completely horizontal transmission (see Figure 2)

after the printing plate enters the machine, it is directly heated through a narrow table. Since there is no common developing liquid tank, the developing liquid does not need to be constant temperature. The liquid medicine is placed in a cubic container with a capacity of 10 liters, which is enough for 220 ~ 250 plates (the size is 50cm × 70cm) for development. The potion is pumped to the cloth applicator. There is a narrow gap between the two metal strips, through which the developer drops on the moving plate to form a thin liquid film. The developer acts on the emulsion within 12 seconds. At the end of the developing part, the liquid medicine film is removed through the extrusion roller, and the remaining developer is discharged together with the used stabilizer

1. Plate feeding table 2 Plate heating zone 3 Cloth head development 4 Fusing of 2 nozzles 15 Fixing of 1 nozzle 2

6 Gluing of 1 nozzle 7 Drying section 8 Plate receiving desk 9 twenty μ M and 3 μ M particle filter

80 ml of liquid medicine is enough for each square meter of plate development. Even if it is not produced, the pump will be switched on and off several times, so that the cloth coating head is not easy to crystallize. Considering the consumption of developer when the pump is switched on and off, the amount of developer per square meter of the printing plate is calculated as 100 ml, and it is not necessary to supplement the solution every time after the development

after the development of the printing plate, the main fixing and auxiliary fixing (washing) are carried out. A small amount of liquid medicine with large shrinkage is sprayed on the printing plate through the nozzle from the tank with a capacity of 14.6 liters and 6 liters, and brushed away. The first tank supplies liquid medicine through the second tank, and is continuously pumped through two purification filters, even if the diameter is only 3 μ M gelatin and silver halide particles will not leak. Stabilizer consumption (including regeneration) is 115 ml per square meter. After that, conventional gelatinization and drying are carried out, and the running speed of the printing plate is 110cm per minute

eco system does not need to be connected to water pipes, and the consumption of liquid medicine is very low (the printing plate throughput of 500 square meters per month can reduce the consumption by 75%), and the cleaning cost and sewage discharge cost SBS rubber has good elasticity and the ability of crack self-healing is the least. When the printing plate throughput is small, the disadvantages of this kind of teaching method are self-evident, and the developer is more

at present, the width of this machine is 88cm. Size 70cm × A 100cm printing plate is fed with a narrow side. 50cm × 70cm and 35cm × 50cm printing plate is imported with wide edge. Now, the p-alpha 880 super eco plate making machine can realize online development with Mitsubishi alpha 2500 V computer plate making machine directly, and online development with other CTP machines has also been included in the plan

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