Gravure: The preferred way of high quality EPN

Gravure development to today's excellent situation is formed through the joint efforts of many industries: such as equipment manufacturing, ink, solvent, plate making industry, the adoption of new technologies, the implementation of new processes in the printing industry, etc. are all driving the gravure to the prosperity and development The direction of the move.

In many cases, gravure printing not only competes fiercely with flexo and offset printing, but it also fights all kinds of popular theories. Gravure is the simplest form of Ep, J, but its role is not understood: for example: high cost of gravure plate making, which makes many packaging products to abandon gravure and traditional offset printing. Do not forget that gravure cylinders can be used multiple times, with up to 3 million to 14 million impressions per set. This is characterized by stable performance, a wide range of applications for inks and substrates, and easier handling than offset and flexo. . At present, with the successful development of ink-based manufacturers for environmentally friendly inks such as alcohol-soluble inks and water-based inks, the technical progress of gravure printing is maximally promoted. At the same time, in the field of plate making, the search for substitute materials for chrome-plated steel rollers and copper rollers will continue to reduce costs, improve the economic benefits of gravure printing, shorten the pre-press adjustment time, and eliminate short-run printing defects. At the same time, as the price of domestic high-speed gravure printing presses is adjusted, the cost will continue to decline, which will eventually increase the market share of gravure printing. The author firmly believes that gravure will become the preferred method for high quality EPN.

Gravure trend
1. Substrate: PVC, PP plastic labels, soft packaging of PET, PE, and various composite materials; coated paper/cardboard soft and hard cigarette packs; ordinary wet strength paper/aluminized paper/aluminum foil labels, and textile printing and dyeing.

(1) Gravure Printing Flexible Packaging: The quality of commodity packaging increasingly affects the motivation of consumers to purchase goods. The gravure printing still dominates in the field of flexible packaging composites such as plastic bags, plastic boxes, paper and plastic, aluminum-plastic and aluminized films. The large-scale gravure printing machine can complete compound, cross-cut, and die-cut in-line processing, which is suitable for large-scale long-length tasks and also promotes the popularization and application of various composite materials. The future gravure printing technology adopts the design of a compound environment, which has reliable performance, simplified structure, convenient operation, short product replacement time, and shorter production cycle. It is more and more common to install trolleys on gravure printing machines, and have various forms of composite functions such as wet, extrusion, and dry processes. Saving resources, protecting the environment, reducing costs, and displaying the appearance are the mainstream of the development of composite packaging films in the future.

(2) Gravure-printed aluminum foil: Ultra-thin aluminum foil is an indispensable composite substrate for flexible packaging. Since the surface is silver-white, applying gravure printing produces a strong metallic luster, which is low in cost and can highlight the grade of the product. The country is mainly gravure, and 100% of the country uses gravure printing.

(3) Gravure Printing Paper Label: The main domestic tobacco plants and tobacco packaging EPN plants basically use imported gravure printing machines Ep~, J cigarette pack paperboard and coated paper, which represent the highest level in the domestic printing industry, gravure printing The advantages are fully utilized. Therefore, high-speed gravure presses are called "printers." Under the influence of the competition mechanism, professional cigarette packet printers have turned their attention to the growing beer market. The color separation, ink transfer, overprinting, and die-cutting are all controlled by computers. The printing quality and processing accuracy are better than the offset Ep~, J. Nothing less.

(4) Gravure Printing Carton: Decorative paper and tipping paper are coated, printed, glazed, and rewinded on a high-speed, high-precision, wide-format paper gravure printing press and sent to the corrugated production line as cardboard. Its exquisite designs, rich colors, and strong viewing qualities make the carton highly compressive, wear-resistant and moisture-proof.

2. Ink: Customers not only pay attention to fine patterns, but also pay more attention to the environmental protection requirements of printing. Gravure inks contain a large amount of volatile organic solvents, which account for almost 50% of gravure ink components. Among them, aromatic hydrocarbons contained in low-boiling, highly volatile solvents such as xylene, toluene, ethyl acetate, butanone, etc. It is both toxic and flammable and is not conducive to environmental protection, health and safety. In recent years, with the application of an efficient solvent recovery system, pollution has been relatively reduced. The rapid development of water-soluble gravure inks and electron beam curing inks at home and abroad has created a platform for gravure printing. This type of ink contains no volatile organic compounds and meets the requirements of environmental protection. The development of new optimized Uv inks can be applied to the printing of plastic materials as well as printing non-absorbent paper and paperboard. The author firmly believes that it will have a vast market space.

3, plate making
(1) Automatic Gravure Roller Plating Process.
(2) Quickly implement the non-film engraving process: electron beam engraving and laser engraving.
(3) Implementation of digital rapid proofing using a graphic database.

Development direction of domestic gravure printing machine
1, a wide range. Such as compatible machines, dual-receiving dual release, India and India on-line machines. Due to the characteristics of modern packaging and changes in the printing business, flexible packaging printers hope to have multi-function printers, paper and plastic compatible printers, paper and aluminum foil compatible printers, and paper, plastic and aluminum foil compatible presses in order to compete in the market. Get initiative. Double-receiving and double-replacement multi-unit gravure printing machine, with two sets of independent retractable material structure, two sets of tension control system, can be arbitrarily combined into one or two independent gravure printing machine. The printing and compounding machine can be used either as a printing press alone or as a dry copying machine. It is also possible to use both models at the same time. After the machine is online, printing and compounding operations can be completed at one time. It not only satisfies the anti-counterfeiting requirements of high-grade printed multicolor and shallow web, but also improves work efficiency.

2. Cardboard preprinting machine with pre-printing function of corrugated cardboard. Carton preprinting is a process for printing web paper with a gravure printing machine. The printing speed can reach 150.180 m/min. The width of the printing material can be matched with the corrugated cardboard line. Its overprinting accuracy is high, the printing ink is saturated and the color is bright and firm. Once printed and varnished, it is the best process for obtaining high-quality cartons at home and abroad. The use of a large gravure printing press for multi-color printing on a web, the printing of a finely-printed web as a final compounding process for a corrugated paper production line on a cardboard box, to form a corrugated cardboard box with a high-grade pattern, through the longitudinal Cut, die-cut into a single box board.

The production process is as follows: gravure printing surface paper (web) - production line corrugated cardboard - computer slitting - computer cross-cutting - die-cutting indentation (flat or circular flat die-cut) into box. With high production efficiency, high printing quality, high corrugated box strength, suitable for large-volume long-lived and other features.

3. The competition between domestic and foreign packaging and printing machinery is becoming increasingly fierce. Enterprises should cooperate with the trend of overall industrial automation, focusing on R&D technology and developing high-speed printing machinery. The unit-type structural framework has been basically established, and no major changes will occur within the next 3-5 years. The main breakthrough is in some basic technologies. The specific efforts are:

(1) Intelligent control mode. Develop remote diagnostics for high-speed gravure printers, provide remote services and workflows, and design system solutions for specific machine fault points.

(2) Diversification of equipment functions. Developed a wide range of flexible packaging printing equipment with a variety of switching capabilities, such as printing and coating line, printing compound line, printing, die cutting, cross cutting, indentation line, etc., to meet the market demand.

(3) Structural design standardization and modularization. With the original organic modular design, new models can be converted in a short time.

(4) High-precision movement of institutions. By applying motors, encoders, digital control (NC), power load control (PLC) and other high-precision controllers to complete, and appropriate product extensions, research in the direction of high-tech products. Such as "Drawer-style closed printing unit research and development", "printing products online testing", "tension pendulum axis", "balanced receiving and discharging unit", "periodically lubricated rail support" and so on.

(5) Shaftless transmission technology. The use of electronic gears instead of traditional mechanical gears to remove the driveshafts has the advantage of avoiding the effects of twisting of the driveshafts and gear gaps on the tension and overprinting of the printing press, achieving a higher degree of synchronous operation and realizing the modularity of the printing press. .

(6) Hybrid technology for specific applications and added value added through line production.

(7) Development of UV drying technology. Such as microwave drying, logistics support system and peripheral technology development.
(8) R&D of large-format printers.

(9) Sensing and Control Technology. Ensure quality stability and production optimization to achieve and maintain print quality observability and reliable reproduction.

(10) The reliability of the front desk operation.

In short, gravure will move toward multi-purpose, multi-color, high-speed, automation, linkage and environmental protection.

Source: "China Packaging Industry"
(author/Sun Jingzhong Cheng Xiliang)