Process-related cutting fault analysis
1. Unreasonable process design
Printing is a related work, starting from the process design, it is necessary to seriously consider how to meet the requirements of post-press binding and processing. For circular ordering books, in addition to the design of cutting lines, but also need to consider drilling, setting index labels and other factors, not only to ensure that all the pages can be arranged in the correct order, and so that each binding process can meet the operation requirements of the next process. Any link out of control, may make the original process design requirements can not continue to implement, directly affect the binding of the processing quality and production schedule.
2. Cutting margin is too small
No matter whether there are bleeding images in the books or periodicals, we should avoid the phenomenon of too small amount when cutting. Usually it is difficult to guarantee the cutting quality below 1mm. There are two reasons for the small margin: one is once tried; second, the other is the design problem of the product itself. If the cut margin is too small, you can only increase the cut to reduce the size of the finished product.
However, the increase of the cutting amount will have a great impact on the posterior binding process, and will directly affect the accuracy of the folding page and the correct performance of the cross-page image. Therefore, in the daily work, want to try to avoid this situation, to ensure that the print matter is left at least 3mm cut amount.
3. The rules and mouth lines are not clear
During the cutting process, keeping clearly visible regular lines and diao lines on the print can reduce cutting errors and save cutting time. At the same time, the print should also be cut in the same direction, so as to ensure the positioning accuracy. If the regular line and diao line are blurred, cutting must be careful, through calculation and measurement.
4. Fur edge phenomenon
The appearance of rough margins in the print can seriously affect the appearance. The use of incorrect paper pressing force, knife edge passivation, paper warping or too much at a time to load when cutting will cause the margin phenomenon.
The corresponding preventive measures are: adjust the paper pressing force, replace the paper cutter before cutting, to ensure the correct water content of the paper, reduce the loading volume, etc.
5. Different types of paper loads are different
Most porous paper is suitable for sufficient cutting, high density paper and heavy pressing paper is suitable for small loading volume. To ensure cutting quality, each load should be below 50% of the maximum capacity. If the product has a bleeding pattern, the edges of the paper will be more obvious, so be more careful.
Analysis of cutting faults related to printed materials
1. The paper texture is too hard
Generally speaking, the harder the paper, the more difficult to cut. Coating paper has more clay components, so the surface texture is hard, in the cutting process needs to often replace the paper cutting knife, serious times to change twice a day. Recycled paper is also not easy to cut, because such paper contains a lot of impurities in addition to the paper fibers. When cutting this kind of paper, no matter what preventive measures are taken, it is difficult to cut the whole batch of live parts neatly and consistently.
After a binding fault occurs, you should first identify whether the fault is caused by paper factors.
The judgment method is: take different paper for cutting. If the previous fault repeats, the fault has nothing to do with the paper; If the fault disappears after the paper is replaced, the fault is related to the paper.
2. The ink dries too slowly
Poor dry ink can also cause cutting failure. Pay more attention if radiant blue or other dry, slower ink is printed on the paper. At this time, if the normal paper cutting pressure is used, the undry ink will cause the back adhesion; if the paper pressure is reduced, although the back adhesion problem can be effectively improved, but it will cause the knife drift phenomenon.
The correct approach is to add the drying oil for the trap in the printing process to ensure that the product is thoroughly dried before entering the binding process.
Although the above work is the responsibility of the printing department, but the binding department must also do a good job of acceptance when receiving products.
The specific method is: take out a piece of print from the inside of the paper pile, and rub the drawn print with another piece of paper. If the pattern on the print is stained, it is not sufficiently dried. In addition, large areas of the field is also prone to dry too slow problem.
Cutting process for special prints
1. Map products
The quality of the map depends on the accuracy of the cutting and the accuracy of the folding. After undertaking the map post-press processing task, the relevant departments must design an accurate processing scheme before cutting. The paper of the map is thick, if not cut properly, it is easy to produce the cover and the bottom surface of the warping phenomenon after the folding, and affect the appearance of the picture at the crack of the map folding. Especially 10 fold or more than 10 fold of the map, to pay special attention when cutting, strictly ensure the cutting accuracy, to prevent the generation of folding after the external page is significantly shorter than the internal page phenomenon.
2. Folding pages
Before cutting and folding the insert page, we should first try to cut it first, and then test and fold it. The two processes are indispensable, and judge whether the gap in the middle is correct. If the gap is too small, readjust the cut; if the gap is too large, indicate that the cut is too large. If the cut is reduced, it is still can not be corrected, and there are just some cracks located at the junction of color, which is more difficult to deal with, and is likely to cause the accident of the whole batch of products.
3. Book books and periodicals
If the sheet sheet is printed, cut, page matching, to coil binding, then the cutting requirements are often relatively high. The cut page should be flat and consistent from the appearance. When cutting products with bleeding pattern, the operator is required to have rich operation experience, otherwise it is easy to change the page position, resulting in the crooked bleeding pattern of the finished book.
Due to the production process of ring books including printing, folding, tie, glue (back), the core three sides cut, book back single cut, punching, ring, after finishing the back of the cutting, to gently knock two core on the desktop, shock the residual glue in the page, and will cut the paper after cutting, to ensure the quality of the punching, ring.
Recommendations for binding and external processing
In the need for external packaging business, many enterprises always want to arrange some homework as far as possible, in order to reduce the cost of external processing. If the product in the enterprise first cut, and then sent to the external processing unit binding. In fact, this will have many potential effects on the binding quality.
The correct approach is: if other units need to complete the binding work, you should outsourcing the cutting and binding work together, do not split the complete binding process. In this way, if there is a binding quality problem, the responsibility is relatively clear, both units will not shirk each other, but also can enhance the sense of responsibility of the external processing unit. Because the binding quality is largely affected by the cutting quality, so, if the printing enterprise has completed the cutting work itself, it must assume some responsibility for the binding quality.
brief summary
Cutting quality affects the binding quality to a large extent. Whether the completion of cutting work is good or bad not only affects the appearance of the finished printing products, but also is directly related to whether the qualified printing products from the printing workshop can become the final qualified products. Therefore, if printing enterprises want to ensure product quality and improve cost-efficiency, we must pay attention to the cutting problem in the binding process. In order to ensure the quality of printing semi-finished products- -printing sheet cutting, we must start from the paper procurement, and well control the quality of the design, printing, binding and other procedures.
Source: http://news.naliyin.com/
