Gravure Printing and Electromechanical Engraving

Quality. Repeatability. Consistency. Meeting the functionality and design demands of manufacturers requires precision, durability, and expert engineering.

Gravure printing answers the call with a wide breadth of functionalities (metering, coatings, adhesive laydowns) and designs (achieving micron accuracy). These cylinders — electromechanically engraved with microscopic cells to hold ink (or varnish or adhesive) — are the heart of the gravure printing process, a method known for its ability to produce sharp, vibrant images at high speeds.

Creating gravure cylinders in exact sizes to fit specific machinery needs is both an art and science, requiring capabilities and the expertise of skilled engineers.

Gravure Printing: A Cut Above

Gravure cylinders are created through electromechanical engraving, with each cell designed to transfer ink (usually) to a substrate. This method is regularly compared to digital printers, which, despite many advancements, can’t replicate the quality and consistency of gravure printing.

The choice between using gravure cylinders and printers often comes down to the scale and complexity of the project. For large runs of the same item, gravure is unparalleled in efficiency, quality, and detail. For shorter runs, or one-off items, digital printing may be the winner.

The Shape of Ink: Cell Geometry and Its Impact

The geometry of an engraved cell — typically a 45-degree diamond shape — is critical in determining the quality of the print. Different shapes and depths accommodate various ink types and applications differently.

The determination of cell geometry is a deliberate and sophisticated decision, tailored to the ink  and substrate. The best possible outcome for the product drives these choices based on several factors:

• Ink Transfer Efficiency — Deeper cells hold more ink, resulting in richer, more saturated prints

• Print Quality and Resolution — Cells with sharp angles and precise dimensions accurately reproduce detailed designs and fine lines

• Compatibility with Inks — Different ink types have varying viscosities and drying times, which can be better accommodated by specific cell geometries

• Adaptation to Various Substrates — Rough substrates may require more ink to achieve full coverage, so deeper cells are necessary

• Printing Speed and Efficiency — Certain cell geometries allow for faster ink transfer and drying times, increasing overall printing efficiency

• Durability — Deeper cells with more ink generally result in prints that are more resistant to fading and wear over time

• Aesthetic Outcomes — Geometries create varying textures, gloss levels, and visual effects, allowing for creative expression and brand differentiation

Maintenance Matters: A Doctor Blade’s Importance

The lifespan of a gravure cylinder, ranging from under a year to beyond two decades, hinges on diligent maintenance. Regular roll inspection, cleaning, and evaluating the chemicals being run on the rolls (some can eat into the chrome plating) all play into longevity. 

However, one factor is especially important to maintenance: the doctor blade, which not only removes excess fluid from the cylinder but also guarantees the uniform distribution of ink across the cells.

The longevity of cylinders, capable of enduring millions of print runs without compromising quality, is significantly influenced by choosing the correct type of doctor blade — steel versus composite — and ensuring its precise alignment and installation.

An incorrect or poorly aligned blade can accelerate wear or cause damage to the cylinder. With only 1/1000th of an inch of chrome on a standard gravure roll, the soft copper underneath is susceptible to damage if the doctor blade isn’t operating properly.

Proper selection and setup are critical to preserving cylinder integrity and functionality.

Gravure Creation: From Concept to Completion

Electro-mechanical engraving and laser ablation are the two main methods of creating gravure print cylinders. While laser ablation offers the ability to do multiple prints and achieve greater cell depths, it’s often more expensive. The reputation of electro-mechanical engraving’s efficiency and cost-effectiveness has built unmatched trust throughout the industry to deliver superior results.

Successful gravure cylinder creation relies on being performance-focused and comprehensive. Beginning with pattern development, the visual goal is evaluated first. The cylinder is then engraved, chromed, and run through a proof press, ensuring that the chosen design and engraving method meet the project’s performance demands. Only then does the project move to production. Comprehensive evaluation and thinking must continue, with ongoing collaboration between teams.

The PRS Process: Experience Across Industries

Choosing gravure print cylinders is a commitment to quality, precision, and performance. Yet, selecting the right method doesn’t guarantee success. You need to partner with an engraving and roll solutions leader that is dedicated to advanced technology, excellence, and surpassing industry standards. 

Precision Roll Solutions (PRS) is home to the world’s largest electromechanical engravers — able to handle roll sizes of 200 inches in face length and 20 inches in diameter. This capability not only establishes industry leadership, it instantly communicates PRS’s ability to handle a wide array of end-use products in flooring (where rolls are typically very big and long), wall coverings, metals, and decorative films.

Ensuring gravure print cylinder longevity and performance is a priority for PRS. Nickel and chrome plating provides extensive corrosion resistance and durability. Yet, copper plating achieves the ultimate in engraving quality, plus the image can be easily cut off, the copper plate built back up, polished, and an image re-engraved back into it.

When cylinders eventually do need to be brought back to spec, PRS uses repair/refurbishing skills and a full-service machine shop to transform old rolls into like-new condition. From journal rebuild/replacement to roll surface resurfacing to rebalancing to customizing new rolls, nothing beats a team experienced with gravure print cylinders.

A final thought on the PRS process. An in-house design department, led by an experienced veteran in pre-press operation, allows us to create images from scratch, which is a rarity in the industry. Customization provides the opportunity for a customer to use a set of gravure cylinders to make multiple products.

Unmatched expertise. Cutting-edge technology. Open consultation. A commitment to excellence. PRS knows that details make the difference, especially when it comes to gravure print cylinders, which remains a shining example of the value of craftsmanship and precision.

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