Gravure Printing Plates--Truthfulness (II)

1. Quality excellence

Prior to platemaking, gravure platemaking and printing plants generally conduct technical exchanges. In particular, for some difficult-to-live jobs, gravure platesetters must organize special reviews to determine the production conditions and product specific requirements of customers. The best route to meet product requirements.

General Manager Wang mentioned that certain areas are prone to color shifts, such as shallow meshes in highlights, multi-colored browns, light whites (such as teat cups), three-color superimposed grays, and so on. At the time of processing, the plate-making factory must be cautious: Firstly, special processing should be performed on the areas in the manuscript that are prone to color drift. Second, reasonable electric carve lines and electric carving angles should be selected to avoid the range where color drift is likely to occur.

Xu Gong pointed out that for some of the more special fine work pieces, such as special small but must ensure a clear pattern, must take special plate making process, such as carving, laser engraving, etc., not only the number and angle of engraving should be reasonable configuration, There are special requirements for color, and the requirements for machining are also high, such as the degree of mind, coaxiality and so on.

2. Technical support is increasingly prominent

When a printing company encounters difficult problems in the printing process, it usually seeks technical support from the gravure platemaking factory to jointly research and formulate solutions. In fact, in the actual production process, there are many factors that affect the printing quality. It may be the problem of the printing roller itself, or it may be due to the improper control of the printing factory. Therefore, the correct judgment and finding the root cause of the printing failure becomes a problem. key. This puts higher requirements on the technical service personnel of the gravure platemaking factory. It requires that they must understand and even be familiar with the printing process in order to better communicate and communicate with the technical personnel of the printing factory, analyze together, and find out the crux of the problem. Where and take appropriate measures to eliminate, improve their own service quality.

When talking about this point, Wang Zong is very confident and proud, he said, many of Dongyang's technical staff and middle and senior management personnel are from Dalian Dafu Plastic Color Printing Co., Ltd. They all have considerable experience in printing and printing; It also attaches great importance to the training of technicians and sends them regularly to the practice of enrichment, allowing them to experience and understand the printing process. Therefore, in addition to the techniques and knowledge of plate making, the technicians of Toyo often have a certain degree of certainty. The printing production experience, relatively understanding of the printing process, and a certain ability to judge the failure of the printing, so it can easily identify or find the cause of the printing failure, which is also a unique advantage of Toyo, is unmatched by many other gravure plate making plants of.

In addition, according to Wang, Dongyang also provided an “online service” for its large clients. For example, Dalian Dafu Plastic Color Printing Co., Ltd. is one of Dongyang’s current large customers. Both companies belong to the Dalian Shengdao Group and are generally rich. When each new product is proofed or printed on the train, Toyo must send technical personnel to conduct on-site tracking in the past, find problems in time, and jointly discuss solutions.

According to Xu Gong, for new customers, Savailles generally must first send technical personnel to understand the customer's production conditions and process control conditions. When the first batch of roll proofing or printing, it will send technical personnel to the scene to track, timely Find problems and feed back information in time so that the plate making process can be adjusted in the future to improve the quality of the roller and help customers obtain high quality prints.

3. Frequently asked questions

During the interview, we also learned about some problems frequently encountered by some flexible packaging and printing companies in the new proofing and printing process, and consulted the gravure plate-making factory. Here we would like to discuss the more common issues with the printing companies. I hope to be able to help the vast number of friends in the industry.

(1) The plate and text do not match the manuscript

This is a situation that everybody does not want to see. It is not good for the platemaking factory, the printing factory and the customer. But at this time, there is no other good plan but rework. Therefore, when a printing factory makes a plate-making order to a plate-making factory, it is necessary to confess the final dimension of the dimensions and textual content of the clearance piece. In particular, when there is a large amount of information provided by the customer, such as an existing CD, a color document, or a copy , faxes, etc. At this time, we must strictly examine whether the contents of the attached information are consistent, whether there is conflict, and communicate with customers in time, and cannot be taken for granted.

(2) Hue deviation

Due to the application of the digital proofing system, the gravure plate making factory will generally make digital samples before the plate making, so that the printing factory and the customer can confirm, and the effect of the digital proofs is close to the actual gravure effect. Therefore, as long as the printing process control of the printing factory is compared Stability, not much fluctuation, should not appear too obvious hue deviation. This is not a problem for some large printers, and some small printers are not doing well enough in this area and may often encounter such problems. Therefore, the printing process of a printing plant must remain relatively stable.

(3) The layout is easy to dirty

This is related to the quality of the chromium plating layer. In general, the chromium plating layer must meet certain brightness and certain density requirements. Generally, the surface of the chromium layer should be controlled within 400 to 600 strips/cm 2 within this range. The layout is not easy to get dirty. But even a particularly dense chromium layer, if it is rough, is not bright enough, it is easy to get dirty.

Improper control of the printing process can also cause the layout to be dirty. You can try to adjust the printing pressure, ink viscosity and solvent ratio, replace the ink, adjust the squeegee and other methods to solve.

(4) Cutting line

From the plate-making point of view, there are two reasons for producing the knife line. One is the scratch on the copper plated surface, and the second is the low hardness or rough surface of the chromium layer. From the perspective of printing process control, the reasons may include: foreign matter in the ink, scratched the layout; the sharpness and flatness of the squeegee are poor; the angle and pressure of the squeegee are not proper.

(5) Roller with low print resistance

From the perspective of the platemaking plant, this is mainly related to the hardness of the chromium plating layer. Generally, the hardness of the chromium layer should be controlled between HV 900 and 1000. The hardness of the chromium layer is low, which of course affects the service life of the plate roller. Chrome layer hardness is too high, the corresponding internal stress is relatively large, prone to chromium layer burst (also known as "Burst"), will also affect the print roller's resistance to printing. Of course, the low print roll resistance of the printing roller may also be related to the printing process of the printing press, such as excessive printing pressure, improper squeegee angle and pressure, foreign matter in the ink, or improper use by the operator.

(6) Imprinting is not allowed

From the aspect of the printing roller, there are mainly the following reasons: There is a problem with the diameter of the printing roller; the dynamic balance of the printing roller cannot meet the requirements, and a large jump occurs in the printing process. From the printing point of view, the main reasons are: large deformation of the material; improper oven temperature settings; improper tension control or fluctuations.

In order to improve the quality of the gravure roll, reduce the number of rework, and ensure that high-quality prints are delivered to the final customer on time, this requires the joint efforts of the gravure plate making factory and the printing house.

1. Improve communication and exchange

The communication and communication between the gravure platemaking factory and the printing factory is of course very important, but the most important thing is to communicate well with the end customer and make the final customer satisfied. This is the common desire of the gravure platemaking factory and the printing factory. On this point, the two sides' position is the same. Therefore, in order to ensure the smooth progress of platemaking and printing production, and avoid detours, the gravure printing plate-making factory, printing factory and customers must strengthen communication, enhance understanding, and reach consensus.

Wang Zong introduced us to Dongyang's successful experience in this area. He said that in order to enhance the understanding of the three parties, Toyo usually holds several technical exchange meetings with its large customers and its major customers each year. Necessary training. Toyo has even extended its service to the final customer's design company, because many design companies do not understand the gravure printing technology. The files or jobs they design do not meet the requirements of gravure printing at all.

2. Strengthen the stability of process control

The control of the plate making process of the gravure plate making factory and the control of the printing process of the printing factory are all very important, and the two must also cooperate closely in order to ensure that the final customer is satisfied with the printed matter.

Although the whole process of gravure platemaking has basically been standardized and digitized, there are still phenomena of arbitrariness and product quality instability. For example, when the same job is re-plated, there will often be deviations in the quality of the plate roller. The problem is that this is actually a problem in the process management of the gravure platemaking factory. Therefore, the gravure platemaking factory must further improve the stability of the platemaking process in the future so as to ensure the stability of the roller quality.

Similarly, the stability of printing processes in printing houses is also very important. Since there are many influencing factors in printing, in order to ensure the consistency of printing quality, effective measures must be actively taken to ensure the relative stability of the printing process. Only in this way, the gravure platemaking factory can determine the relatively stable platemaking process, and the printing factory can only obtain stable quality prints under relatively stable printing process conditions.

Source: Comin Media