Application of the hottest thin plate technology i

The application of thin plate technology in corrugated board printing

the post press processing and pre press processing technology of corrugated board printing is in a period of rapid development, and great changes have taken place. Monochrome printing business is less and less, and has gradually disappeared, replaced by the rise of color printing. In addition, flexographic plate making technology has also made great progress. The relevant data provided to people can effectively control and eliminate the negative impact of plate brushing (Development) inherent in the process itself

corrugated boxes are made of relatively heavy cardboard after slotting and high-quality surface processing. In order to improve the sales volume of commodities, manufacturers began to work hard on the outer packaging of commodities and strive to improve the attractiveness of the outer packaging of commodities. Therefore, cartons are becoming more and more packaged and commercialized

color halftone printing of corrugated board has become more and more common. The improvement of paperboard production process, the improvement of ink quality and the improvement of roller processing technology have laid a certain foundation for the application of thin plate technology, and effectively promoted the application of thin plate technology in flexographic printing technology

demand creates market

in the printing of corrugated board, a wide range of plate systems are used, such as various types of plates, plates with different thicknesses, plates with different substrates, double-sided tapes with different viscosities, and cushion materials with different elasticity, which can be matched to form a variety of different combinations. Most corrugated board printing manufacturers have tried to test different combinations of different types of plates, tapes, backing materials and inks, and analyzed the results

for a long time, corrugated board printing manufacturers have been longing for a special plate, which does not need any special materials, is suitable for all plate making equipment, and can adapt to tropical, subtropical and continental climatic conditions. Based on this demand, the structure and performance of photosensitive polymers to meet the needs of emerging industries - electric mopeds and new energy electric vehicle projects have been greatly improved, and they can also have very stable operating performance under different climatic conditions. Moreover, even after printing for millions of times, the transfer performance of inks can still remain constant and consistent. What customers need is plates with higher flexibility and better printability. Therefore, this market demand promotes the development of thin corrugated plates

in addition, the latest digital plates have also become an important issue in corrugated box printing. The new and thinner plate used for corrugated board printing has a black protective layer on its surface, which can be ablated by the laser emitted by CTP equipment

according to the development of market 4, the steel bar line offset at the joint shall not exceed 0.1 times the steel bar diameter field demand, the plate supplier has increased the size specification of the plate. The new thin flexible plate has an additional layer of photopolymer, and the variety is increasingly complete. When printing with soft plates, the ink transfer performance is very good, the consistency is good, and the halftone image effect after printing is very good. Therefore, many printing manufacturers have given up their original hard plates and used soft plates for printing. In this way, the time of plate making is saved, which shortens the whole production cycle and reduces the production cost (including the cost of the material itself and the cost related to plate processing)

control the impact of brushing and dot expansion

when printing corrugated board by flexographic printing, in order to eliminate the impact of brushing (developing), it is necessary to adjust the printing pressure slightly higher, which will inevitably cause dot expansion. Generally speaking, the larger the deformation of the printing plate, the more serious the point expansion after printing, and affect the quality of the final print. Therefore, only low line images and thick Yin text can be printed, and fine graphics and texts cannot be printed

in view of this situation, in order to reduce the deformation of the printing plate and improve the quality of the final printed matter, people have taken corresponding measures. The first is to use thin plate technology in the printing of corrugated board

secondly, it is to improve the photosensitive polymer and realize the standardization of the plate system. At present, this kind of plate used in corrugated board printing has been put on the market, and has been continuously improved and perfected in terms of exposure tolerance, which is very difficult, so as to improve the quality of paperboard printing. This makes the thin version technology of corrugated board favored by people

Application in plate making and printing

generally speaking, thin plates with hardness between 32 and 34 shore hardness can basically meet the requirements of corrugated board printing. This plate is specially designed for color halftone printing, line and field printing (suitable for all kinds of substrate materials). After the main exposure, there is a clear color difference between the exposed part and the unexposed part on the printing plate, and the contrast is relatively strong. In this way, the quality of the convex part (graphic part) on the printing plate can be easily controlled

this new type of photosensitive polymer plate also has some other advantages. For example, the printing adaptability is very good, even on very rough and uneven bags, cardboard or other substrates, it can get a good printing effect; Independent dot printing is accurate, and single dot is not lost; The small inscriptions and UPC bar codes are very clear and accurate. The reproduction range of the tone is very wide, and if the printing plate is made under standard conditions, it is very convenient to optimize the reproduction range of the tone. In a word, the exposure tolerance of this new photosensitive polymer plate is very large

from f-flu te and e-flu Te to n-flu te and g-flu te, the requirements for color, hiding power, contrast and other indicators are becoming more and more strict. Printers began to accept and adopt thin plate technology. The technical difference between corrugated board printing and folding carton printing is becoming more and more blurred and less obvious

choose the right plate

the plate manufacturer has made great improvements in the performance of the plate. The dot enlargement rate has been reduced, the ink transmission performance has been higher, the negative impact of plate brushing (Development) has been reduced, and the contrast of halftone printing has also been improved. When printing fine halftone images or line drafts, it is necessary to ensure the consistency of the printed matter. In this case, it is recommended to use new thin soft plates or other thin hard standard plates. Under the action of pressure, the plate must have high elasticity and strong deformation resistance

elastic and compressible plate mounting material is a good choice. When printing with thin plates, a large amount of printing pressure will be absorbed by the foam liner, so that the printed points are very neat and the edge outline is very clear. This requires appropriate pressure according to the type of corrugated board printed, that is, the pressure used between thinner and harder plates and softer plates is different

according to the diameter reduction of the drum and the different types of corrugated board slotting, the best plate liner combination is determined through testing. The plate making time required for thin plates is relatively short, and the deformation of films and plates is relatively small. The relief depth of thin plates should not be less than 0.039 inch, because if the relief depth is too small, you must use a large printing pressure, but a large printing pressure may cause the small Yin text (or Yin line) to paste. Therefore, when using thin plates to print corrugated board, it is recommended to control the relief height of the printing plate between 0.039 inch and 0.042 inch

in order to meet some special requirements of heavy packaging bag printing (for example, printing on film or paper), or when printing on substrate with rough surface, another thick plate with hardness between 42 and 44 shore hardness can be used, which may get the right effect

selection of embossing roller

the function of embossing roller is to ink the printing plate. It is necessary to select a suitable embossing roller to not only ensure that the dots are not lost, but also ensure that the transfer rate of ink from the printing plate to the substrate is relatively high, and the color intensity of ink is also relatively high. According to the requirements of corrugated board printing of different quality grades, the following lists the appropriate corrugation rollers:

1, b-flu te, coated paper: 356 lines/inch corrugation rollers are used, and the theoretical ink transfer capacity is 4.20 ~ 4.52bcm (6.5 ~ 7.0cm 3/m2). The overall printing effect of halftone, text and lines is good

2, b-flu te, uncoated paper: the amount of ink transfer is largely affected by the thickness of the plate and the backing material used. It is recommended to use a 305 line/inch corrugated roller, and the ink transfer capacity is theoretically 5.81 ~ 6.13bcm (9.0 ~ 9.5cm 3/m2)

3, e-flu te, coated paper: for this kind of printing material, the results are very different with different plate types. It is mainly affected by the type of plate, such as the hardness of plate, the collocation of gasket, etc., which are very important and have a direct impact on the final result. Therefore, here we can only provide you with a rough and rough recommended value. You can use the corrugated roller with the number of lines between 356 ~ 405 lines/inch, and the ink transfer volume is between 3.23 ~ 4.52bcm (5.0 ~ 7.0cm 3/m2)

in addition, the composition and viscosity of the ink also have a great impact on the ink transfer performance. When selecting plates suitable for all applications, we should always keep in mind that the interaction between the components of the system, including printing plate, plate pasting material, ink roller and ink itself, is very important. If the choice is correct and the collocation is reasonable, we can get high-quality and consistent prints