GCR IMAGE CONVERSIONS, LASER ENGRAVED ELASTOMER SLEEVES & ECG PRINTING ACHIEVE HEIGHTS ONCE RESERVED FOR GRAVURE
The rotogravure process has been known for its ability to deftly print fine art and photography, and for its unmatched durability in long printruns. But rotogravure continues to be among the most expensive printing processes in our industry today; requiring hundreds of thousands of
impressions to be profitable. There is an alternative. You can now achieve the quality and nearly equal the run length of rotogravure for a fraction of the cost by using laser engraved elastomer sleeves.
For shorter printruns that didn’t require quite the quality of rotogravure, flexographic plates became an alternative, but until recently, there was no clear cut alternative that rivaled high-end rotogravure for print quality and longevity. Flat top dot and high definition (HD) screening have helped bridge the gap for flat plates; but flat plates still fall short when it comes
to longevity, registration ability, and razor sharp text. Now, flexographic printing using laser engraved elastomer sleeves offers all of these abilities.
Laser engraved elastomer sleeves can be leveraged along with technologies like gray component replacement and expanded gamut to offer a high quality, reproducible printing product that is only rivaled by rotogravure.
Elastomer sleeves approach the run lengths of rotogravure cylinders at a fraction of the cost. They are also extremely efficient for short runs because of ease of mounting and impeccable registration – leading to faster makereadies. For a printer, they can make the difference between profit
and loss. For designers, this means you can change printing processes, but do not have to change your designs to convert them from rotogravure to flexography.
Subsurface imaging allows control of graphics and text. Printers can now combine halftoning and line work into one print unit. Engraved flexographic sleeves can hold below 1 percent minimum dot: allowing fuller range throughout the highlight dot for vivid artwork and photorealistic images. This is done with minimal size highlight dots, microns below the surface. Only laser engraving allows control of the imaging of the dot—from the floor, to the shoulder, to the surface, to
reduce surface tension and to control dot gain.
EXPANDED GAMUT FOR LASER ENGRAVED ELASTOMER SLEEVES
The traditional CMYK process limits today’s “jump off the- shelf” graphics intended to attract consumers in a few seconds. Most high-end packaging is now designed for 8-to-10 colors, utilizing CMYK and an ever changing variety of Pantone colors, specific to design families, brands, and logos.
Expanded Gamut standardizes the printing process to CMYK + 3 Pantone colors, such as orange, green, and violet, to achieve difficult colors not in the CMYK printing color gamut. This eliminates the need to constantly swap Pantone color ink formulations on press. By standardizing the same seven colors, printers can purchase ink in bulk and produce the majority of the color spectrum needed. This drastically reduces press setup times, which will, in turn, reduce costs.
Software like Esko’s Equinox has extremely simplified the conversion process for trade houses and printers to achieve consistent great results. This lessens the need for graphic designers to change how they are currently working. Experienced separators can convert most existing designs on the fly. Utilizing the proper ink set and quality conversion software is the key to increasing the color spectrum, maintaining consistency, and reducing makeready costs.
When using expanded gamut, reverse copy that was once a single spot color may now be made up of two-to-three colors to achieve the same PMS match. There’s now the issue of holding reverse copy registration in these areas that wasn’t an issue with a one color PMS spot. This is a challenge for flat
plates, especially when talking about press widths averaging 50-in. and more. Tight tolerances in registration with elastomer sleeves allow printers to hold offset like traps as low as .003-in., which has become critically important for these multicolor reverses.
GRAY COMPONENT REPLACEMENT
One of the best ways to maximize the effectiveness of expanded gamut is to partner it with advanced separation technologies, like gray component replacement (GCR).
GCR is the conversions of full range colors, limited to hue and saturation, as opposed to creating hue, saturation and lightness. The lightening and darkening aspect of the color is removed from the range and added into the black for neutrality, consistency, and control.
Think of colors as white and black colors. White colors are lighter printing and are only adding neutrality and shading, like the cyan in a red apple. Black colors are the heavy printing color, adding saturation and hue richness, like the magenta and yellow in the red apple. In another color example, like a green tree, the magenta would be the white color adding
only neutrality and shading and the yellow and cyan would be the black colors, printing heavy and creating the saturation and hue richness.
GCR is the removal of most, if not all of this white/gray color, from each color and then seamlessly adding it back into a full range black, maintaining the shape and depth of the original. This process opens the window of latitude immensely for the press operator to achieve color without compromise.
Because of the advantages and complexity of GCR, it is important to partner with a company that is experienced in GCR separations.
By using techniques like GCR, cost savings and quality improvements are achieved simultaneously. Also, with files converted to GCR; pressmen now have fewer issues with neutrals varying on press. Neutrals that were once three colors, are now mostly black. With less ink behind grays, you’ll experience much less variation in color overall as environments change throughout your pressrun. Hue changing neutrals are a thing of the past.
In the current “just in time” marketplace – longer pressruns with large inventories are becoming less practical. Because there is now an alternative to rotogravure with a substantial cost savings, designers have more opportunity to change their graphics as customer tastes change.
The decreased cost and increased flexibility of laser engraved elastomer sleeves allows designers to match printed designs to ever-changing marketing needs. Designers can keep the look of their product fresh and original, and more easily incorporate seasonal, promotional, and specialty run instead of having to re-use last year’s designs.
Because of the high cost of rotogravure, many have outsourced their printing to Asia. The advantages and cost savings of flexo when using laser engraved elastomer sleeves are allowing North American printers to reclaim work they once thought lost. Moving work back to North America helps customers speed up print cycles and have more control over how their jobs are printed.
Sleeves are also leading the way toward a greener printing process. Rotogravure often uses very corrosive and environmentally unfriendly etching chemicals and solvent inks. The ability to customize the elastomer compound means that more environmentally friendly inks can be used. Additionally, the laser ablation of elastomer sleeves avoids the pollution involved with the corrosive rotogravure etching process. Standardizing
ink sets with expanded gamut also reduces ink waste.
The most exciting changes in the printing industry are happening in flexography. Laser engraved elastomer sleeves apply the newest and most cutting edge technologies to achieve print quality once reserved only for rotogravure. Flexography can do it for less. Flexography can do it sustainably. And, as an alternative to out-sourced rotogravure, flexography can help keep North American printers in business.