Production Inkjet Printing: Ready for Prime-Time for Commercial, Package Printers?

Mary Schilling, vice president of technical operations at Schilling InkJet Consulting, sees a number of paper-related issues that should be analyzed in the production inkjet arena. They include:

• Whiteness and brightness. Aqueous fluid dries by absorption, so the colorant, pigment or dye—whether using a coated or uncoated sheet—is entering the paper fibers and taking on the paper color. A whiter, brighter sheet is going to make the colors pop and look clean when the ink is introduced. A paper with a more yellow tint, then, will impact the inkjet colorant. On untreated paper it will become magnified, as there's nothing to keep the colorant on the surface.
• Paper porosity. Paper porosity is a concern in the offset process, but is a larger, critical factor in inkjet printing. Excess porosity in a sheet will cause the ink to dive down and through the paper, thus allowing the print to "show through" the paper.
• Paper weight. This correlates with the graphics being printed. When printing heavy coverage (30 percent and up for inkjet), a thin sheet is not going to accommodate as much ink. The ink will dive and the user will fail to garner the necessary build required for image and color quality.

"It boggles my mind that people invest $2 million to $6 million on a piece of high-speed aqueous inkjet equipment, and then choose the cheapest paper they can find," Schilling observes. "It's like using low-grade gasoline in a Lamborghini; you're not going to get the performance you're looking for. In aqueous inkjet, a poor, uncoated, opaque or offset paper will not provide the surface required for good image and color quality.