Plate scrap is common in print production. As we all know, in actual operation, once the plate is scrapped, it will bring a lot of troubles such as waiting for the edition, re-lighting, and reinstalling the plate to find rules. It wastes man-hours, delays product cycles, reduces production efficiency, wastes plates, and increases printing costs. Therefore, based on the author's many years of experience in production practice, this article summarizes the following causes of the printing plate scrap, for your reference.

1 The original plate is wrong

Misprinting of the original plate is the direct cause of the plate being scrapped. Under normal circumstances, without proofreading, the original version of the plate is not easy to find, especially when the manuscript changes greatly. Some of these errors occurred during the process of making plates such as photocopying and imposition, while others were caused by negligence of authors or editors (such as typos, etc.).

2 Making mistakes

There are many situations in which the printing plate can be scrapped in the plate making process. For example, the exposure time is too long or too short to cause the lack of strokes and short strokes; when the printing plate is improper, the printed matter is printed and printed; and the printing plate is stained; At the same time, the printing staff accidentally damaged the graphic part; the development was not so good, etc., which would cause the printing plate to be scrapped. Sometimes the baking process is too short. After printing on the machine, the printing rate is low, or the printing staff will incorrectly print the printing plate and the storage is not good. The printing plate is oxidized, which will also cause the printing plate to be scrapped.

3 Improper handling by printing operators

In the printing process of the printing plate, sometimes the front side of the printing product will appear dirty. This requires the operator to perform on-site processing of the problems related to the printing quality found on the printing plate. The processing method is naturally varied and should be handled according to the situation of the printing plate. If some printing plates are processed by baking, they cannot be removed with the correction paste when removing the stains. Only the blade or the needle can be used to remove the dirty spots. If it is slightly inadvertently, the images will be scratched. Causes the printing plate to be scrapped; for the plate that has not been baked, a correction paste is used in the treatment. Because the etching paste has a particularly strong erosion on the surface of the printing plate, the graphic part is more easily damaged, resulting in printing. The version is scrapped.

4 mechanical failure

Failure of machinery during the printing process can also result in the plate being scrapped. This is an accident. For example, during normal printing, the sample that has been sampled has traces of being rolled, and the inspection of the machine indicates that the imprinted spring that has been dropped is damaged. In this way, the plate is scrapped when it is severely damaged and cannot be repaired. This situation is not uncommon. In fact, sometimes the clips above the delivery teeth drop off or the screws of Feida fall off. Once in the roller, it will damage the plate and cause the plate to be scrapped.

5 Abnormal wear

The printing rate of the printing plate has a great relationship with the quality of the plate, the effect of the printing plate on the printing plate, the degree of baking, the pressure of the printing roller and the printing roller. In the same way, the same printing plate is printed on different machines, and some machines have more plates in the middle and some have fewer machines. This explains the problem of high and low printing rates, and at the same time, it also proves that some machines wear abnormally on the printing plate. Once the printing plate wears out, there will be a plate-off phenomenon, which will affect the quality of the printed product and the printing plate will be scrapped.

Miao Yinzhen

Source: "Printing World"