In the domestic gravure printing industry, there was a saying: "Seventh Edition, three-point printing." Although it may be exaggerated, it can be seen that the importance of gravure printing plate. However, for many people and even many gravure printing plants, gravure printing plates can be said to be a mysterious field. They lack deep understanding and understanding of the gravure platemaking industry. In order to further enhance the communication and exchange between the gravure platemaking factory and the printing factory, the two sides will achieve more understanding and cooperation, and jointly promote the healthy and rapid development of the gravure platemaking industry and the gravure printing industry. We have interviewed several well-known domestic concaves. Printing plant and flexible packaging gravure printing plant. Here, Mr. Wang Jun, General Manager of Dalian Dongyang Gravure Printing Co., Ltd., Mr. Xu Weiguo, Chief Engineer of Shanxi Yuncheng Savares Printing Co., Ltd., Mr. Dai Junli, Minister of Quality and Technology Department of Shannan Southwest Light Industry Co., Ltd., Heilongjiang Longhua Packing Products Co., Ltd. Ms. Zhang Yan and Mr. Liu Yonghua, who have worked in gravure printing for many years, expressed their sincere thanks!
Plate-making factory, to improve the quality of plate-making
High-quality roller is the prerequisite and prerequisite for the gravure plate making factory to participate in the market competition. The digital proofing system and experienced technicians can be said to be the right hand of the gravure plate making factory. The standardized process management is the gravure plate making factory. A reliable guarantee for success.
1. Digital proofing system, the right hand of the plate making factory
At present, there are two kinds of digital proofing systems used in the gravure platemaking industry: one is the IRIS digital proofing system, and the other is the EPSON proofing system. In comparison, the IRIS digital proofing system is more professional, and its color reproduction performance is better. The IRIS proofs are more exquisite and more realistic, especially the effects of the image hierarchy are more refined, and are generally used for the proofing of high-end products.
The digital proofing system has many advantages and benefits the gravure platemaking factory. Through the control and adjustment of the color management system, the proofs made by the digital proofing system are close to the actual OPP proofs, and the actual gravure effect is restored. Therefore, the digital samples can help the plate makers to find out before the plate making. Problems, and to take appropriate measures to correct and adjust, in order to improve the quality of plate making, reduce the rate of rework; Second, the application of digital proofing system is more conducive to the control of the entire plate process, and can guarantee the stability of plate making process and plate quality, Consistent; In addition, digital proofing is quick and easy, which can greatly shorten the plate making cycle and guarantee the delivery date.
In the domestic gravure platemaking industry, Shanxi Yuncheng Savares Plate Co., Ltd. and Dalian Dongyang Gravure Plates Co., Ltd. should be regarded as pioneers of the digital proofing system. Savaras introduced the IRIS digital proofing system as early as 1995, and Toyo adopted the IRIS digital proofing system from 1996. Both companies later introduced the EPSON proofing system.
2. Experienced technicians, valuable assets of the plate making factory
In fact, the digital proofing system only provides a reference standard sample for the gravure platemaking factory. In order to obtain high quality products, it must rely on the handling and adjustment of the operator. For now, there is no ready-made theory or formula for the gravure platemaking industry that can be applied. Many times in production, it still depends on the experience of operators. Therefore, operators, especially color separation personnel, must have a relatively high level of technology and considerable skills. With rich experience, it is difficult to get the ideal product. This is why some gravure plates mills use color management and digital proofing systems, but they still do not have the root cause of high quality products.
Nowadays, more and more jobs are being replaced by spot color technologies. Spot color substitution refers to using other colors instead of black, blue, magenta, and yellow to reflect the colors and levels of images. For example, they use ultramarine to replace green and use red. Instead of magenta, substitute brown for black and so on. At present, the phenomenon that many chocolates are packaged in the market using spot color substitution technology is more common, and there are more cases of printing with brown instead of black. This kind of craft is more difficult, and the ordinary digital proofing also basically loses meaning in this, it is very difficult to express the effect of the designed spot color correctly, in this kind of situation, how to guarantee the correctness and reliability of the color separation data and the color of the picture and The correct reproduction of the hierarchy? This depends on the color separation personnel's experience and technical level. Of course, the conditional gravure platemaking factory can use the Cromarin proofing system to achieve spot color proofing, but due to the higher cost, it is less used.
General Manager Wang said that in Toyo, when color substitution technology was first adopted, it was necessary to check the suitability of color separation results by means of Cromartin-like samples. Later, through continuous experiments and explorations, it gradually accumulated certain experience and mastered. Some basic rules, and customers are also satisfied with product quality, so now basically no longer rely on Cromartine.
3. Standardized process management, reliable guarantee of success
The standardized management of platemaking process is very important. The platemaking process involves multiple processes, including order taking, review, color separation, design, machining, electroplating, electric carving, and proofing. All processes must be institutionalized and standardized. Management and control.
Before making the plate making process, we must understand the customer's printing production conditions and figure out the job requirements. For one thing, from the point of view of the printing process, there are points on the surface and India, and the performance and processing methods of the two are different. Secondly, the performance of printing equipment, such as the accuracy of overprinting of domestic gravure printing machines, printing speed, and stability, is generally inferior to that of imported gravure printing machines. This must be taken into account when making plates. It cannot be generalized. Third, the types of film materials used are different, such as OPP film and PET film, matting film and pearl film, and their respective performances are also different, and the printing process and requirements are also different. In addition, the customer's production environment, such as whether the workshop is closed, whether the installation of a constant temperature and humidity device, whether it is clean, etc., are also very important, gravure plate-making factory must be in response to these circumstances platemaking process "personalized" processing.
Mr. Wang stressed that the stability of the customer's printing process is also crucial, otherwise it is difficult to obtain a stable and consistent product. In general, a large customer or a printing plant with a certain scale has relatively stable production conditions and process control. Therefore, it is also possible to stabilize a corresponding electric engraving process curve for the specific customer, and then specify the specific job. Requires some corresponding fine-tuning during the plate making process.
Xu Gong pointed out that some customers are limited by the printing equipment and the production environment, and the phenomenon of poor ink transfer rate, high light, and the loss of small outlets in the shallow part of the network often occurs. However, customers hope that they can print even under such production conditions. Qualified products, so they may ask the plate maker to help them solve the problem. Encountered this kind of job, in the production of electric carving files, you can take some necessary measures, such as some customers less than 3% of the small outlets can not be printed, in the face of large areas of high-light small outlets must consciously avoid 3 % Smaller outlets below %, properly increase the value of outlets in highlights, ensuring that customers will not be screened when printing.
Proofing is also an important part of the process control of the gravure plate making factory. For example, the brand and grade of the ink used for proofing, the viscosity of the ink, the proofing speed, the proofing pressure, and the temperature and humidity control of the proofing room must be standardized. At present, the common practice of gravure plate making factories in proofing is to select different grades and quality inks for the different requirements of customers at different levels. According to Wang, the ink used by Toyo during proofing is roughly divided into high, medium and low grades. In general, large customers or high-end products use high-grade ink for proofing, such as DIC and Dalian Schmidt's inks; For small customers or ordinary products whose requirements are not too high, low-grade inks are used when proofing, which can avoid the effect that the printing factory cannot achieve with the high-grade ink proofing by the plate-making factory when printing with low-grade ink; second, the plate-making factory can also Save some costs.
(to be continued)