Print Business Glossary: Post-Press Coatings and Coating Equipment

1. Print Business Glossary: Post-Press Coatings and Coating Equipment      Liquid coatings can change the durability, look, and feel of all types of printed materials.             Different formulations exist to improve the visual appeal or endurance of the hundreds of             different products that can be produced with different combinations of inks, toners, and             substrates.                                                  For example, different coatings have been developed for coated offset paper, packaging             paperboards, canvas, wallpapers, vehicle-wrap vinyls, plastics, aluminum composite boards, and         corrugated.                           A direct-mail postcard must withstand scuffing from mail-handling equipment, while an outdoor             vinyl wall mural needs to endure long-term exposure to sunlight, pollution, and/or graffiti. The               coatings applied to inkjet-printed art canvases must remain flexible when the canvas is           stretched around the wooden bars in a gallery wrap.                                             Here is some of the terminology related to different types of post-print coatings, coating                 techniques, and coating equipment.               Types of Coatings  Aqueous Coatings ​are low-cost, water-based liquids that are typically designed to protect higher           volumes of printed pages on paper. Available in matte or gloss finishes, aqueous coatings             protect prints such as business cards, magazine covers, and full-color book pages from             fingerprints and scuffing. They also keep metallic inks from tarnishing when exposed to air.             Aqueous coatings are typically applied in-line during offset press runs and dried with forced air             or infrared systems. Special formulations of aqueous coatings can be overprinted with           toner-based addressing systems or written on with a number-two pencil.                                                                                                

2. A ​Soft-Touch Coating is a specialized aqueous matte coating that adds a velvety, suede-like             feel to the printed piece. Textured coatings use a mix of large and small particles to create the               desired effect.                                          Solvent Coatings were developed to protect fine-art prints output with water-based dye inks or             on materials that aren’t resistant to water. The print colors will run if an aqueous coating is               applied to aqueous dye inks. Solvent coatings are typically applied with handheld rollers,             brushes, aerosol sprays, or spray guns. The work area must be well-ventilated to minimize               exposure to VOCs (volatile organic compounds) in solvent coatings.                                                                    UV Coatings form a hard film on the print surface when exposed to controlled wavelengths of                   UV light. Different UV coatings have been developed for output from toner-based presses, inkjet               presses, and wide-format printers that use latex, solvent, or UV-curable inks.                              Varnish is a clear gloss, matte, or satin ink that is typically used to add shine or visual effects to                       selected areas of a print. Varnishes can be applied in-line on an offset press or with a digital                 enhancement press that uses inkjet printheads.                                          Techniques  Flood Coating covers the entire printed page with the coating. Flood coating can be used to add               a gloss or satin surface to matte papers printed at high speeds on a production inkjet press. The                     coating helps make digitally printed pages look like offset-printed pages.                                        Spot Coating ​changes the look or feel of logos or text on a printed page. On an offset press, an                   additional plate must be created to apply a spot coating to a specific area of the print. Digital                 embellishment presses (such as Konica Minolta’s MGI JetVarnish or Scodix presses) use clear           UV-curable inks to apply spot coatings to inkjet prints on paper, synthetic papers, and               paperboards used for folding cartons. The placement of the spot coating is dictated by data             from the digital print file.                                                                                               Types of Equipment  Web-Fed Coaters are built to handle the rolls of materials printed on ​offset or digital web               presses​. They are built to handle different roll widths and sizes. Tec Lighting makes high-speed                 Web UV coating machines for continuous feed inkjet printers.                                   Sheet-Fed Coaters ​are designed to apply coatings to prints on cut sheets. Shops that need to             coat a high volume of printed sheets can use a coater that feeds and stacks prints                 automatically. Manual sheet-fed coaters are available for coating small runs of prints.                                       Anilox Metering ​systems use laser-engraved rollers to apply a consistent thickness of coating           on every printed sheet.                   Some coaters for production inkjet or toner presses can coat both sides of printed papers               simultaneously. Other coating machines can also apply pre-print primers to improve ink or toner                                            

3. adhesion to films, plastics, and other super-smooth substrates. Some models can be set up             in-line with die-cutting, hot-foiling, creasing, folding, and perforating prints.                  Roller Coaters ​use rollers to feed sheets of thin and thicker rigid materials beneath a series of                 doctor rollers, scrapers, and application rollers that apply a controlled thickness of the coating.             Specialized roller coatings are used to apply coatings to flat sheets of glass, laminated wood,               and metals.                                                      Liquid Laminators are ​wide-format roll-to-roll coaters​. Devices such as the Marabu StarLam           1600 and Tec Lighting MegaCoat XL were created as an efficient, low-cost alternative to               applying adhesive-backed laminating films to flexible prints from 50 to 63 inches wide. Many           wallcovering materials and vehicle wrap graphics are protected with liquid laminates. The Welte           AquaSeal 3300 can apply liquid coatings to rolls of flexible materials up to 129 inches wide.                                                                 To see different types of coaters in action, watch these videos:  Tec Lighting Inc. XtraCoat offline UV Coater  Kompac Kwik Finish 32 - UV & Aqueous Coating Machinery for Flood and Spot Coating  Marabu StarLam 1600R – Part 1: Startup and Running  Follow Us on Social Media  Follow Ordant on ​LinkedIn​, ​Facebook​, or ​Twitter to learn when the next post in our             print-business glossary series is published.    Related Posts:  Print Business Glossary: Automated Wide-Format Graphics Cutters                    Print Business Glossary: Finishing Equipment for Offset Presses  Print Business Glossary: Emerging and Niche Print Processes