The preprinting of gravure printing carton is to pre-print the corrugated carton on the wide web (carton paper) with the required fine pattern before making the corrugated cardboard, and then printing the good paper in roll shape. The upper corrugated board production line is made of corrugated boxboard, and then the die-cutting machine is die-cut into a box type.
At present, 30% of the total output of corrugated boxes in some developed countries such as Europe and the United States adopts preprinted new technologies. With the rapid development of the paper packaging industry in China, many customers have been stable in recent years, such as Mengniu, Budweiser and Qingdao. Beer, etc. have turned their eyes to new pre-printing technologies. With the packaging and packaging of beverages, beer, home appliances and foodstuffs in the design and usage of corrugated boxes, the use of web preprinting to produce high-grade colored corrugated cartons will become a future package. Industry development trend.
â— Web preprinting is better than flat offset preprinting
At present, the vast majority of domestic color cartons use flat sheet offset printing pre-printing methods. The process flow is: cut web into sheet paper → offset printing machine printing single sheet of paper → simultaneously single-sided machine roll two-layer corrugated Paperboard → Face Paper and Single-faced Corrugated Paperboard are lapped on veneer or veneer veneer → die-cut indentation forming → nail box/glue box.
The technological process of the web gravure printing preprinting technology is: gravure printing machine printing surface layer paper roll → cardboard line production cut into three (or five) cardboard → die-cutting indentation molding → nail box/glue box.
So why do you need gravure preprinting? There are two main reasons. One is that gravure printing can easily provide high-quality color prints; the other is that electronic engraving technology can significantly reduce the production cycle and cost of metal plate rollers, which is close to or even lower than that of flexographic plates. Moreover, the domestic Shaanxi Beiren has produced a high-speed wide-format paper concave machine, the price is only one-third of the imported flexographic printing press, and the gravure pre-printing method may be more suitable for the actual situation of packaging companies in China.
In comparison, people often refer to the commonly used printing process as “post-printingâ€. Pre-printing has some obvious advantages over post-printing:
- Get higher print quality and adaptability. The pre-printing is performed on a smooth paper surface using a gravure printing machine or a flexographic printing plate. Compared with the printing after printing using a printing slotting machine to print on uneven paperboard surfaces, fine color printing with richer layers and brighter colors can be performed. Printing quality will also be more stable and reliable.
- The highest strength of corrugated board can be obtained, because the pre-printing does not need to imprint the board after it is formed, so as to avoid the corrugated deformation and the weakened board strength. After printing with a corrugated board printing slot machine, each color printing will cause more or less deformation of the corrugated cardboard, and the more the number of colors, the greater the effect on the deformation of the corrugated cardboard.
- High production efficiency, ease of production management, low scrap rate, etc. Preprinting has become an important trend in the printing of corrugated board, especially the printing of high-grade cartons (including large and special-shaped cartons).
The use of intaglio printing carton preprinting has the following salient features compared to traditional color offset printing:
--high productivity. Gravure printing web printing speeds up to 150-200 m/min, basically matching many corrugated board production lines in China, shorter than traditional flat-sheet offset printing and veneer lapping, low labor cost and high efficiency.
- Color carton produced by gravure pre-printing can get high-quality ink prints. Due to the high precision of gravure printing, it is not more than 0.2mm. Gravure printing can also be completed once by printing and varnishing. General gravure printed wire after printing Up to 300 lines, gravure printing ink than other printing methods, up to 4.5-6g/m2, ink ink full, soft, bright, solid, and gravure printing after each color has a full drying system, Therefore, under the premise of choosing the paper with higher surface smoothness for printing, the gravure printing can obtain high ink printing quality. Most cigarette packs are made from paper gravure printing. At present, the domestic production of paper gravure printing inks has been relatively mature, and domestic production of water-based paper gravure printing inks capable of meeting the pre-printing of corrugated cardboard lines has been completed, which can fully satisfy the friction of 180°C high temperature and hot plate on the corrugated board production line.