Research Printing Defects of Flexible Packaging

A study of the modern state of technologies for the production of flexible packages by gravure printing was carried out. The analysis of patent information over the past ten years has revealed the constant development of technologies for ensuring the quality of printing, new materials — inks and films. According to the received data, the main number of patents is registered in the USA, Japan and China. Total number of patents devoted to new polymeric materials for printing is more than twice as large as the number of patents for gravure printing inks. From the obtained data, it can be concluded that this area has many unexplored points, and therefore it has a development perspective and space for various researches. The occurrence of defects, as well as the quality of products, is influenced by three main factors: manufacturing, technological, raw material. Another human factor can also influence the occurrence of defects. As a defect caused by the human factor, the most common is the use of the wrong series of ink, abuse of solvents, failure to carry out timely washing and cleaning of form cylinders and squeegees, failure to comply with approved technological regimes (drying temperature, pressure, speed, amount of glue application, etc.). According to the results of the printing of flexible packages, the types of defects caused by the production factor can include: insufficient tension of the canvas, insufficient alignment, insufficient drying of the ink. As a raw’ material shortage, the most common are: sagging of the canvas, non-fixation of ink, non-printing of a shallow raster, low intensity of ink, insufficient activation of the material. The most common printing defects of flexible packages have been determined: no small raster printing, different tone (in one edition), non-combination of design elements, not gluing laminates, layering of laminates, insufficient film activation, stains and splashes, drying of the ink (non-uniform application of the ink layer), ‘Stairs’, Stripes, no printing/poor printing of design elements. According to the results of the analysis of the wastes, no-good of print circulation, the main reasons for its occurrence were analyzed and the primary reason were identified. According to the identified types of defects, possible ways to eliminate each of these types of defects are proposed.