There are many processes in printing. To get a good print, every process must have no problems; On the contrary, it is impossible to get high-quality printed matter if there is a mistake in one process. Printing is divided into pre press, printing and post press. Then, let's discuss the impact of these three processes on print quality:
1. Prepress
original quality and color level are important factors restricting printing quality. Whether the selection, color and color matching of color originals meet the requirements of plate making and printing has become the main factor affecting the overall printing quality. In particular, photos ignore the requirements of printing plate making, which directly affects the overall quality of printing. The picture is the pen of drawing the dragon's point. It is a vivid picture with bright colors, rich layers and clear and realistic images, which gives readers the enjoyment of beauty. It is hard to imagine that a group of originals with serious color deviation, lack of gradation and virtual deformation will produce a wonderful effect. Poor quality originals can be processed, but it should be clear that picture information can only pick up information on the basis of the original, not recreate information. Each adjustment will lose a lot of hierarchy and color information. The basic principle of this work is to be faithful to the original, higher than the original, and strive for unity of style.
in the process of image processing, we should mainly master the following points:
① adjustment of picture hierarchy.
② Color correction is to reproduce the color reflected by the original (not the original itself).
③ for the conversion from RGB to CMYK format, the picture format used for printing must be CMYK format.
④ sharpening, sharpening is an effective means to improve image clarity.
2. Printing
with the emergence of digital printing machines, many parts of printing have been automated, which has made printing a big step forward. However, the limitation of printing quantity makes traditional printing machines and digital printing machines complementary. Printing is a very important process. Of course, there are many technical points.
first of all, mastering and controlling the balance of ink and water is the key to steadily improve the printing quality. Ink and water balance is the basis of printing. Only with proper ink and water control can the printed newspaper be clear, the ink color is consistent, and the overprint can be accurate. This requires the following in practical work:
① pay attention to the proportion of fountain solution.
② Adjust the supply of ink in time according to the quality of paper.
③ Controlling the environment, temperature and humidity of the workshop is conducive to improving the printing quality.
④ When purchasing auxiliary materials, try to meet the needs of ink balance.
⑤ strengthening the maintenance and inspection of printing equipment is a means to improve printing quality.
⑥ Regularly check the pressure of the transmission part.
3. Post press
Post press operation is also very critical. This step is related to the presentation of finished products. If the post press processed products are not acceptable to customers, all the previous efforts will fall short of success. Note two points:
1. Impact on printed matter surface:
for example, the gloss, color richness, wear resistance, heat resistance, moisture resistance, corrosion resistance and other properties of printed products are increased through polishing, calendering, covering, blistering, film covering, hot stamping and other process methods, so as to improve the service performance and quality grade of printed products. Common factors affecting glazing quality include paper performance, temperature, ink and crystallization.
2. Impact on the appearance and overall coordination of printed matter:
processing technology, such as binding quality, cutting size, indentation shape, trimming, adhesive effect, etc; Will affect the appearance and overall coordination of the printed matter, and the quality of packaging and mounting will also directly affect the quality and grade of the printed matter.
in fact, in this printing process, there are many factors affecting the quality of printed matter, which need to be grasped in practice. The above is only a focus discussion.
