Gravure printing plate new technology

Due to its high printing speed, high printing plate printing rate, and wide printing width, gravure platemaking has always been the preferred printing method for millions of products. Gravure prints are thick, rich in ink and rich in three-dimensional, and are recognized as high-quality prints. After entering the 1990s, the full development of electronics and computer technology has transformed the production of gravure printing plates from traditional corrosion methods to electronic engraving methods. The change in production methods has resulted in new gravure plate rollers in terms of accuracy and quality. Leap.

The use of electronic engraving gravure makes gravure products more exquisite, and its scope of application is also greatly expanded, from the original simple plastic packaging, paper packaging, to pharmaceutical packaging, decorative paper, floor leather and Other fields. After nearly a decade of development, electronic engraving technology has become quite mature. Gravure printing plate manufacturers are also rushing into the country. Now the number of engraving machines is nearly ten times that of the early 1990s. Although the scale of gravure printing is expanding and the technology is mature, there are inherently many shortcomings that have not been effectively improved. For example, small text below 5 points, thin lines below 0.1 mm, shallow webs below 5%, and serrated edges And so are the bottleneck of gravure printing. The effect of printing is not as good as that of offset printing. To develop, we must have innovations. Can we use gravure to achieve the effect of offset printing and simulate the effects of silk screen printing? In this regard, our company has also conducted a lot of research and many experiments while introducing new equipment and new technologies. Finally, we have made new breakthroughs in the bottleneck problem of gravure and further expanded the gravure printing field.

I. Laser engraved gravure In 2001, our company introduced DIGILAS laser from German SCHEPERS company. It has the most advanced multi-beam laser engraving function, which overcomes the weaknesses of electric engraving machines such as hairiness and hair weakness, and is characterized by thick coloring and clear writing. It is especially suitable for printing plates with particularly small but demanding texts such as smoke plates and tipping papers.

Because the laser beam is small and the engraving accuracy is high, the accuracy of the gravure pattern made by laser engraving is not different from that of the electric engraving. In addition, the mechanical accuracy of the roller is much higher than that of the electric engraving plate. The roller has high mechanical precision and is more suitable for high-speed printing. The following electric carving machines also have the following incomparable features:
1. The number of screens and screen angles of the electric engraving machine are influenced by the power and pin angle of the engraving machine and have a certain fixed range. The laser engraving is not limited by the cable and screen angle. Network lines from the straight carved to more than 200L/cm, the screen angle can be any angle.
2. The shape of outlets is various. Commonly used square, round, hexagonal, straight line. You can also edit different shapes of dots as you need. The electric engraving machine can only sculpt diamonds.
3, laser engraving can show half a dot, the edge of the line or the edge of the text, the presence of half a dot to ensure the smooth edge of the line, neat play a great role.
4. The finest line that can be engraved reaches 0.02mm, the minimum English height is 0.25mm, and the Chinese 0.35mm.
5, laser because of the randomness of outlets, so you can artificially deal with outlets, make the edges of the text more smooth, more conducive to the transfer of printing.

Second, the pattern of anti-counterfeiting technology recently appeared in the anti-counterfeit version of the field of packaging anti-counterfeiting, in fact, its use has a long history, in securities, notes used in anti-counterfeiting has been very extensive. Compared with other anti-counterfeiting measures, it has an absolute advantage in terms of anti-counterfeiting costs, but what about when it is used in gravure printing? What is the difficulty in making it in combination with gravure? How to solve it?

Pattern lines are lines that are arranged according to a certain geometrical rule, and the patterns with decorative and anti-counterfeiting functions are formed through line density variation, thickness variation, color depth, hue change, and the like.

The application of pattern printing is very extensive. In our daily life, there are traces of various currencies, securities, certificates, and identity cards. In terms of its practical value, it has anti-counterfeiting performance. In terms of aesthetics, it has appreciative features. The anti-counterfeiting patterns made with imprint have the characteristics of “beautiful, eye-catching, easy to identify, difficult to imitate”.

The pattern of prints is varied and flexible, and its composition can be divided into various types, roughly including: ground grain, flower, relief, lace, miniature, latent image, unlock, raster, print, filter, etc. Multiple units. These units can be used independently or in combination. The design of various components is also very variable, and different styles can be designed according to the designer's style.

Anti-counterfeit version is also the most practical one relative to other anti-counterfeiting methods. Now commonly used anti-counterfeiting technologies such as: laser holographic image anti-counterfeit, ink security, printing technology anti-counterfeiting, destructive anti-counterfeiting technology, code anti-counterfeiting, structural anti-counterfeiting technology, material security, color anti-counterfeiting, etc., these anti-counterfeiting methods have a common feature : With the increase in printing volume, the cost of anti-counterfeit is also increasing. The anti-counterfeit version is just the opposite. The anti-counterfeit design is completed in the plate making. It is realized in printing, and the investment is one-time. The more the printing volume, the lower the anti-counterfeiting cost.

The pattern of the print pattern is a uniform arrangement of thin lines or small patterns of regular arrangement (see Figure 4), and these are for the electric engraving machine, in order to perfectly show that they are a certain degree of difficulty. The engraving of the electronic engraving machine during the engraving is arranged according to the three parameters fixed by the network cable, the screen angle, and the network value. It will not adjust the dots on each line according to the arrangement of the lines, and this will inevitably result in each line The dot size and dot arrangement on the lines are not the same, and the thickness of the line after the printing transfer is of course not the same. The same is true for small patterns that are arranged regularly.

For the different design styles of the plate patterns, we used a laser engraving machine for processing and achieved good results. In the foregoing, we have already mentioned various features of laser-engraving platemaking. Its extremely strong ability to express small text and fine lines precisely meets the requirements of the pattern pattern for engraving effects.

Third, decorative ink gravure process Now on the market in the tobacco, alcoholic high-grade packaging box, often appear similar to metal etching, or radial light effect, or a wrinkle-like effect, these effects are UV Decorative patterns, we call them frosted, refraction, wrinkles and so on. These effects are now produced in two ways. One is the use of a roll press method, which uses a textured roll to show the pressure on the paper. The second is the use of screen printing methods, with UV ink printing performance.

The roller plate method is relatively difficult to make, so it is not used much. The most commonly used is the screen printing method, and the screen printing method requires a different decorative effect is the use of different properties of the UV ink, generated by the ink when the UV lamp curing changes. This determines that the effect of screen printing cannot be completely uniform, and that when multiple effects are required on one box, multiple printing is required.

With the improvement of the printing quality requirements of users, new and more advanced technologies and printing methods must be developed. For this reason, we have developed a new process for printing decorative patterns using gravure printing, which is mainly used for printing tobacco, wine, and health products. Such as high-end packaging, has a very good decorative effect, but also a very good security.

The use of gravure to print decorative patterns is determined by the characteristics of gravure. Compared with screen printing, gravure ink is not as thick as the screen, but it is much thicker than offset or flexo. We have developed and modified the ink and printing machinery so that UV inks can be printed by gravure printing, and the thickness of the ink layer can meet the needs of printing decorative patterns. The greatest advantage of the gravure printing UV decorative pattern is that the pattern produced is determined by the arrangement, size and depth of the dots and lines at the time of plate making. For this purpose, different patterns can be printed with one kind of ink. As long as we make a pattern with different effects such as sand, refraction, ice, wrinkles, or coral on a plate, printing with one ink at a time is very easy. Using different gravure process, with different properties of UV ink, we can get different decorative patterns. Different types of decorative patterns We can use a single printing roller to print one ink at a time, greatly improving production efficiency and enhancing anti-imitation performance. Another advantage of using gravure printing is that the consistency of the printing is good. Whether we print 100 sheets or print tens of thousands of sheets, the effect of the decorative pattern in the final printed product is exactly the same.