Wrinkling of paper in printing will inevitably affect the printing quality. Correctly analyzing and accurately judging the cause of wrinkling and promptly resolving and eliminating wrinkle failures are issues that are worthy of attention by site operators and management personnel. This article talks about the relevant issues.
In order to identify the cause of paper wrinkling in the actual printing process, comparative methods can be used for analysis and judgment. The method is: the unprinted paper (obviously, the quality of the paper for comparison should be normal) is replaced by a mouthwash for printing. If the wrinkling part of the paper is fixed, it can basically be judged as printing. Parts of the machine are improperly adjusted; if the part of the paper wrinkles changes, it can be determined that the paper itself is deformed.
First, improper adjustment of printing press parts
1. If wrinkling occurs in the dentition position of the impression cylinder, the wrinkle shape extends from the gargle to the direction of the wand. It can be considered that the reason is that the individual impression force of the impression cylinder is insufficient. In this case, we must carefully examine and re-adjust the pressure of the dents of the impression cylinder.
2. If the rules for positioning the paper in the left and right direction, that is, the position of the gauge, are not appropriate, the paper may also wrinkle. The wrinkles generated by this reason are usually on the edge of the paper, and the wrinkle shape is from the top to the bottom, from the inside to the outside. In this regard, wrinkling failures can be eliminated after the specification has adjusted the location of the regulations.
3. When wrinkling between two crooked teeth near the mouth, it is generally due to the unevenness of each tooth pad that is used to feed the teeth. Therefore, it is necessary to adjust the transfer pad so that each tooth pad on the tooth row is in the same straight line, and at the same time, the force of each tooth is to be uniform and uniform.
4. Embossing roller dents and feed paper teeth will also produce paper wrinkles when the teeth are too small. This wrinkle is close to the mouth, and the wrinkle shape is a horizontal or circular shape. Obviously to exclude such wrinkles must check and adjust the size of the impression cylinder tooth and open teeth in order to achieve the appropriate.
Second, the wrinkling caused by the deformation of the paper itself
We know that paper is very sensitive to the temperature and humidity of the air, and the moisture content of the paper always changes with the temperature in the air. Such changes generally result in the following two conditions.
1. Fleece: Due to dampness in air, Zhang absorbs moisture and the paper absorbs moisture in the periphery, while the middle part remains the same size or only slightly changes. In this way, wrinkling is straight at the tow. The method of exclusion is to place the paper in a drying room at an appropriate temperature for the purpose of flooding. If the wrinkles are relatively slight, they can also be directly processed by the knocking method.
2 tight edge, this is because the paper in a dry air environment, the paper faster dehydration, and dehumidification is often in the surrounding part of the paper, the water content of the paper around the part of the change is faster than it is to have tension status. This tight edge wrinkle is also not fixed. The solution is to re-hang the paper, and sometimes it is also possible to sprinkle water around the paper so that the edge of the paper is even and flat.
Source: Shanghai Ruishi Printing Co., Ltd.
Plastic Shoe Tree Rack
A shoe tree holds a shoe in its proper shape so it dries out correctly, and keeps the leather from cracking by wicking away moisture. The absorbent wood also helps dry out the lining of shoes so that they don't rot from the inside out.
Shoe Tree,Plastic Lady Shoe Tree,Man Shoe Tree,Lady Boot Sheath
Dongguan Meijiamei Decorative Material Co., Ltd. , http://www.cabinet-fittings.com