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The Environmental Aspects of UV Screen Inks: Past, Present, and Future

(December 2007) posted on Thu Jan 03, 2008

If developing a sustainable graphics-printing process is a goal for your business, consider how the latest generation of UV-curable screen inks can help. This discussion looks at the history of UV inks, recent ink-formulation developments, and ways you can increase productivity while helping to reduce carbon dioxide emissions.


By Laura Maybaum

Many manufacturers develop all their multipurpose ink lines so that colors are made to the same specifications for each line. Customers using more than one multipurpose UV-ink line from the same manufacturer will find that color reproduction is much more predictable. Settings from the art department through printing need much less adjustments since the inks are printing the same. Predictable results lead to more efficient printing.

More stable printing refers to the ability of the ink to achieve consistent color reproduction from print to print both initially and throughout the print run. As solvent inks are printed, the solvent evaporates and the ink viscosity thickens, resulting in color changes on press. The printer will add additional thinner to the ink, again changing the color on press. The color reproduction of UV inks stays much more consistent on press because there is no solvent to evaporate. Printers using UV graphics inks today are able to achieve consistent color very quickly, which leads to higher efficiency, less energy consumption, and less waste.

Lower ink deposit/higher ink mileage In addition, today’s ink includes various rheologies of halftone colors. This allows a printer to match an ink’s print performance to the appropriate press. Newer presses have been built to print faster and faster, requiring the ink’s rheology to keep up. Ink with thinner rheology is able to print faster and, at the same time, print with a lower ink deposit. A lower ink deposit leads to higher ink mileage and less ink on the printed surface.

Keep in mind that the overall amount of ink on a print is incredibly small. The typical range of UV graphic ink deposit can vary from 0.25 to 0.5 mils. Typical total ink deposit of multiple colors is about 1 mil. Substrate thickness ranges from 5 mils up to 15 mils or more. Table 1 charts the range in percent of the total graphic thickness that UV ink typically represents on different material thicknesses.

 
COMPARISON OF INK THICKNESS TO TOTAL THICKNESS OF PRINTED GRAPHIC SUBSTRATE

 

Tomorrow’s ink

In developing tomorrow’s greener UV inks, manufacturers are looking at the overall scope or footprint of the screenprinting process and ways to make it more sustainable with regard to environmental issues. The main concerns relate to renewable resources and recycling.


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