What is a rotogravure printing press? 

In-depth Analysis of working principle of rotogravure printing mahine

Analysis of the Working Principle of Rotogravure Printing Machine: Interpreting the Beauty of Precision Machinery and Craftsmanship through the Example of ZONBON Brand

Rotogravure presses, a historically significant and technologically mature printing process, is renowned for its thick ink layers, saturated colors, rich gradations, and exceptionally high plate durability. It is widely used in high-end packaging, securities, bills, publications, and art albums. This article delves into the core working principles of gravure printing presses and, by examining the technical features of the industry-renowned ZONBON brand gravure printing press, systematically elaborates on the complete process from pre-press plate making to finished printed products, showcasing the precision mechanical design and outstanding printing performance behind it.

Overview of Gravure Printing: Definition and Characteristics

Gravure printing, as the name suggests, features image areas (the parts to be printed) that are recessed below the plate surface. This fundamentally distinguishes it from relief printing (where images are raised) and lithography (where images and non-image areas are nearly on the same plane).

The core working principle involves the use of ink cells to store ink. The depth and size of these cells determine the amount of ink transferred, thereby producing patterns and colors of varying density and gradation on the substrate. The ZONBON brand gravure printing press builds on this classic principle and, through continuous technological innovation, achieves industry-leading levels of printing precision, stability, and efficiency.

Key Characteristics:

Thick ink layers, vibrant colors: Thanks to the ink cell storage, ink layers are significantly thicker than those in other printing methods, resulting in strong three-dimensional effects.

Rich gradations, excellent reproducibility: The depth of ink cells can vary continuously, allowing for fine reproduction of image brightness and contrast levels.

High plate durability: Plates are typically made of steel cylinders coated with copper and chromium, capable of withstanding millions of impressions.

High printing speed and efficiency: Suitable for continuous printing of large-volume, long-run jobs.

Wide range of substrates: Can print on various materials, including paper, plastic films, metal foils, and composites.

Core Working Principle of Gravure Printing Press

A standard gravure printing press (such as ZONBON models) primarily consists of an unwinding unit, printing units, drying system, rewinding unit, and tension control system. Its core workflow can be broken down into four key steps:

Pre-press preparation: Electronic engraving and chromium plating

Before printing begins, the plate cylinder must be prepared. Modern gravure printing uses electronic engraving plate-making technology. Based on digital files, an electronic engraving machine uses a diamond stylus to engrave countless ink cells of varying sizes and depths into the copper surface. Deeper cells hold more ink, resulting in darker colors after printing; shallower cells hold less ink, producing lighter colors. After engraving, the cylinder surface is electroplated with an extremely hard layer of chromium to enhance surface hardness, wear resistance, and corrosion resistance, ensuring the ink cells remain stable during prolonged high-speed printing. ZONBON equipment demands extremely high precision for the plate cylinders, which is the first cornerstone of print quality.

Inking and doctoring: Precise ink transfer control

Inking: The plate cylinder rotates at a constant speed, with its lower portion immersed in a flowing ink fountain, filling all the ink cells and pores on the cylinder surface with ink.

Doctoring: This is a critical step in the gravure process. A highly flexible steel doctor blade is pressed against the plate cylinder surface at a precise angle and pressure. As the cylinder rotates, the doctor blade completely scrapes off excess ink from the non-image areas of the plate surface, while the ink within the cells (image areas) is retained. ZONBON printing presses are equipped with high-precision doctor blade mechanisms and pressure control systems, ensuring even and stable doctoring without ghosting or blade lines, which is key to achieving clean printing results.

Impression and transfer: Successful image replication

The substrate (e.g., film or paper) is driven by the impression roller into tight contact with the doctored plate cylinder. The impression roller (typically made of rubber) applies significant pressure, pressing the substrate into the ink cells of the plate cylinder. Through adhesion and pressure, the ink within the cells is successfully transferred to the substrate surface, thereby replicating the image completely. ZONBON equipment features a well-designed impression system with evenly adjustable pressure, adaptable to substrates of different thicknesses, ensuring efficient and complete trans

Structural Analysis of High-Speed Rotogravure Printing machine

Analysis of Core Structure and Technology of High-Speed Gravure Printing Press

Abstract: As a core equipment in the packaging and printing industry, high-speed gravure printing machines dominate applications such as flexible packaging, decorative materials, and paper product packaging due to their thick ink layers, vibrant colors, wide substrate compatibility, and high printing speeds. The realization of their exceptional performance is rooted in their precise, stable, and efficient overall structural design. This article aims to systematically dissect the core structural components of high-speed gravure printing machines, explaining their working principles and key technologies from a professional and rigorous perspective.

I. Machine Overview and Architectural Philosophy

Modern high-speed gravure printing machines typically employ a modular design (satellite or unit-type) to meet the demands of multi-color, high-speed, continuous printing. The basic workflow is: Unwinding → Tension Control → Multi-Color Printing → Drying → Cooling → Rewinding. The entire machine structure is built around the three core concepts of "high speed," "precision," and "stability." Seamless collaboration among all subsystems is essential to ensure stable, high-definition print quality at production speeds of 600 meters per minute or even higher.

II. Detailed Analysis of Core Subsystem Structures

Unwinding and Rewinding Units

These units form the foundation for continuous production. Modern high-speed machines commonly use dual-position automatic splicing turrets to achieve non-stop roll changes, significantly enhancing production efficiency.

Unwinding Section: The core consists of a magnetic particle clutch or vector servo motor control system. Through feedback from tension detection devices, it precisely controls the unwinding tension of the substrate, ensuring smooth and vibration-free material entry into the printing unit.

Rewinding Section: Driven by vector servo motors and floating roller tension control systems, it achieves constant tension or taper tension rewinding. Advanced combination technologies of center rewinding and surface rewinding effectively prevent issues like misaligned winding and "orange peel" patterns, ensuring quality for large-diameter products.

Printing Unit

The printing unit is the "heart" of the gravure press, and its structure directly determines the printing outcome.

Impression Structure: Consists of a precision-engineered plate cylinder (gravure cylinder), impression cylinder, and inking system.

Plate Cylinder: Made from seamless steel tubes through electroplating, grinding, electronic engraving, or laser engraving. The depth and shape of its cells determine the ink transfer volume.

Impression Cylinder: Typically a passive roller coated with high-quality rubber. Its hardness, elasticity, and solvent resistance are crucial for ensuring complete transfer of ink from the cells to the substrate. It provides precise and stable line pressure to the plate cylinder via pneumatic or hydraulic devices.

Inking System: Mainly two types:

Open Ink Pan: Traditional structure, simple but with high ink volatility, prone to solvent imbalance, and less suitable for high speeds.

Fully Enclosed Doctor Blade System: Standard in modern high-speed machines. This system seals the doctor blade, plate cylinder, and impression cylinder in a chamber, using negative pressure extraction to significantly reduce solvent evaporation, improve the working environment, and stabilize ink viscosity. It is a key technology for high-speed printing. The doctor blade angle, pressure, and material (usually steel blades with specialized plastic tips) require fine adjustment to completely remove ink from non-image areas of the plate cylinder surface.

Drying and Cooling Systems

Instantaneous drying of ink is critical for high-speed printing.

Drying Oven: Each printing unit is followed by an efficient hot-air drying oven. Using an energy-efficient hot-air circulation system with precise temperature control instruments (e.g., PID control), it zones control the inlet and return air temperatures to ensure solvents are completely evaporated in an extremely short time while preventing substrate deformation due to overheating.

Cooling Roller: After drying, the substrate temperature is high and must be immediately cooled by a large-diameter water-cooled cooling roller. Its role is to set the ink layer, eliminate internal stress in the material, restore the material's physical properties, and provide a stable foundation for the next color printing. The surface temperature, smoothness, and cooling efficiency of the cooling roller directly affect registration accuracy.

Tension Control System

Tension control is the "lifeline" throughout the entire process of unwinding, printing, and rewinding. The system monitors tension changes via tension sensors (dancer rollers, floating rollers, or ultrasonic sensors) distributed across various units. Signals are transmitted to the central control system (PLC), which dynamically adjusts the torque or speed of drive motors to form a closed-loop control. Stable tension is an absolute prerequisite for ensuring accurate registration and avoiding material wrinkling or stretching deformation.

Drive and Control Systems

Drive System: Modern high-speed gravure presses fully utilize "electronic shaft" (shaftless drive) technology. Each printing unit and guide roller set is driven by an independent servo motor, synchronized with the main control system via high-speed fieldbus (e.g., EtherCAT). Electronic shaft drives eliminate traditional mechanical long shafts and gearboxes, simplifying structure and improving precision. They enable functions such as "electronic registration," pre-registration, and automatic plate cylinder angle synchronization, significantly reducing plate change time.

Control System: Centered on an industrial computer (IPC) and programmable logic controller (PLC), integrated with a human-machine interface (HMI). Operators can set and monitor all process parameters (speed, tension, temperature, pressure, etc.) via touchscreens. The system includes intelligent functions such as fault diagnosis, data logging, and remote maintenance, forming the core of digital and intelligent production.

III. Auxiliary Systems

Automatic Registration System: Uses photoelectric sensors to capture registration marks of each color group. By calculating deviations and fine-tuning the phase of the plate cylinder or the position of the substrate, it achieves automatic registration, ensuring precise overlay in multi-color printing.

Automatic Ink Viscosity Control System: Online real-time detection of ink viscosity, automatically adding solvents to maintain optimal viscosity, ensuring consistent print color, and reducing manual intervention.

IV. Conclusion

The high-speed gravure printing machine is a complex system integrating mechanical engineering, materials science, fluid dynamics, automatic control, and information technology. Every detail of its structural design—from the extremely rigid machine frame foundation to micron-precision bearings and rollers, down to millisecond-response control systems—aims to achieve the ultimate unity of speed, precision, and stability. With the advancement of "Industry 4.0," the structure of high-speed gravure presses continues to evolve towards greater intelligence, modularity, and sustainability, providing indispensable and powerful support for high-end printing manufacturing.

Specifications for flexible packaging gravure printing machines: 8-color 1050mm wide gravure printing machine, 9-color 1050mm wide gravure printing machine, 10-color 1050mm wide gravure printing machine, 8-color 1250mm wide gravure printing machine, 9-color 1250mm wide gravure printing machine, 10-color 1250mm wide gravure printing machine, 8-color 850mm wide gravure printing machine, 9-color 850mm wide gravure printing machine, 10-color 850mm wide gravure printing machine：

Specifications for decorative material gravure printing machines: 4-color 1350mm wide gravure printing machine, 5-color 1350mm wide gravure printing machine,

4-color 1400mm wide gravure printing machine, 5-color 1400mm wide gravure printing machine, 4-color 2250mm wide gravure printing machine, 5-color 2250mm wide gravure printing machine, 5-color 1650mm wide gravure printing machine, 8-color 1950mm wide gravure printing machine, 8-color 2100mm wide gravure printing machine, 8-color 260mm wide gravure printing machine, 8-color 2900mm wide gravure printing machine;

Specifications for heat transfer gravure printing machines: 11-color 850mm wide gravure printing machine, 12-color 850mm wide gravure printing machine, 13-color 850mm wide gravure printing machine, 14-color 850mm wide gravure printing machine, 15-color 850mm wide gravure printing machine, 11-color 650mm wide gravure printing machine, 12-color 650mm wide gravure printing machine, 13-color 650mm wide gravure printing machine, 14-color 650mm wide gravure printing machine, 15-color 650mm wide gravure printing machine.