Gravure packaging surface drawing, common reasons for analysis

Drawing is one of the problems often encountered in the gravure printing, such as improper handling will affect the flexible packaging products production and quality. Usually black, green, magenta wiredrawing phenomenon is more obvious, and generally appear in a large area of shallow online. , scraping blade mouth or under the knife with foreign body can move up and down in the printing process, before and after scraping knife, hanging adhesive foreign body or directly on the scraping blade with a bamboo stick out ( Must be finished by skilled operators, so as to avoid unnecessary loss caused by improper operation) And, if necessary, need to stop to clean up scraping blade. 2, printing ink circulation is not part of the ink in the ink slot corner position, due to can not get good circulation resin precipitation, form the crystallization of different size and agglomeration, or too dry skin surface ink ( During the spring and autumn summer skin prone to ink, ink because of the influence of the temperature crystallization and agglomeration situation more) Part of, with the cycle of ink, ink crystallization or ink skin was turning version of drum to the blade, scraping blade will be broken to form a random drawing. So must be conducted from two aspects of the cycle of ink and filtering improvements. 1, cycle improvement. Method a, will ink tank tilt, ensure the ink can be made by injection, slightly high end flow from one end of the lower, form a good circle; Method 2, the ink tank flat, but must ink from both ends of injection at the same time, from the middle backflow, so also can form a good circulation, not from the unilateral injection of ink. 2, filtering, improved. Ink before use must be first filter, even the new ink to filter, commonly used 140 mesh/inch. Method is below the set of a silk stockings, ink fountain on the way out into a filter, set in the filter after a period of time, if the filter is blocked, poor flow of ink, can be set on the top of the bucket skewer inserted a few small holes, increase the effect of ink. Set down to the bottom of the bucket can also play the role of good deposited impurities. 3, ink plate inking fatigue the situation occurred in more flexible packaging products area is small. In the printing process, the ink resin is consumed, if continuous adding solvent without adding new ink, resin is not complement, make the ink change the proportion of each component, resulting in ink fatigue and affect the normal use. Appropriate to add a new ink can solve the problem. Two, drawing phenomena caused by plate 1, plate surface treatment in the process of carving gravure, carving the edge of the mesh point to form many small burrs, these small burrs in the printing process will damage the scraping knife, wire drawing. In general the new easy to appear this kind of circumstance, within a certain range, with the increase of printing, drawing will gradually decrease. This requires in version drum production process, on the one hand, to ensure the engraving copper layer's hardness is moderate, reduce carving process of small and medium-sized burr formation, need to get the copper layer after carving processing; On the other hand, to regulate the chrome layer of polishing process. The plate surface grinding, polishing, general can solve the problem of drawing. 2, the installation of the plate if the flexible packaging products circumferential beating big plate in the printing process, may also cause wire drawing. This needs to be checked plate, edition axis ( With no shaft to check the top) Concentricity, check whether the bearing and transmission parts deformation, wear, or even whether the base level, etc.