Commercial Printing: Printing Brilliant Ink Jet Color

Photo purchased from … www.depositphotos.com

I may have mentioned this before in a prior PIE Blog article, but I always fill in the business reply card that accompanies the EPSON direct mail brochure that comes to my door every few months.

Each promotional box that comes to me in response to the business reply cards includes inkjet samples printed on EPSON equipment. These speak volumes.

A Sample Press Sheet

The most useful of these samples is a small press sheet that is just under 12” x 18”. It’s also a poster and an advertisement (in this case, for EPSON SureColor P-Series printers), but it clearly shows me a number of things about the technology, and over the past several years I have seen dramatic improvements in the output.

Like an offset press sheet, this 12” x 18” sample includes a series of printers’ bars. These show solids and shades of the four process colors (cyan, magenta, yellow, and black) ranging from a 20 percent screen to a 100 percent solid. Granted, this is a simulation using a spray of minuscule spots rather than traditional halftone dots.

(This is the nature of inkjet printing compared to offset lithography. You don’t use traditional halftone screening. You build up continuous tone images with a spray of minuscule inkjet spots.)

So if the sample doesn’t reflect traditional halftone screening, what good is it as a measure of EPSON’s quality? The answer is that these two large-format, pigmented inkjet presses can print color screens as good as, or better than, what you can produce via offset lithography.

This particular inkjet printed sample I’m looking at also includes brilliant, large-format imagery. Colors are much brighter and intense than you would find in offset commercial printing, particularly in the oranges, greens, and purples.

This is because of the ten-color EPSON inkset (compared to the four process colors). Using ten colors allows the inkjet press to match far more PMS hues than offset lithography, unless you are using many extra offset press units for additional colors. (You might want to research Hexachrome and “touch plates.”)

The imagery in EPSON’s sample includes both square-edge pictures and silhouettes, both photos and illustration. It also includes a gradation (it looks like a long piece of fabric) that transitions from yellow to purple to blue. What we can learn from this is that EPSON inkjet printers can produce smooth gradations without any of the banding or artifacts that sometimes appear in inkjet presswork.

This EPSON poster/press sheet also demonstrates EPSON SureColor P-Series’ capabilities in printing typography. It includes the following samples, which are most instructive.

1. 1. It includes small sans serif type (perhaps 10pt with extra leading) reversed to white out of a complex photo that shifts in color from yellow to purple. The type is imminently readable. But so is the even smaller type (perhaps 4pt) surprinted over a photo that transitions from yellow to orange. Both of the preceding samples are set in uppercase and lowercase type (which makes them more readable than paragraphs typeset in all capital letters).

1. Another paragraph is set in all capital letters. The words are printed in a medium blue over a dark blue halftone. The type should be hard to read (it is also set “solid,” which means it has no extra leading, which would improve legibility). But you can still read the lines of type effortlessly.

As I’m describing this poster, you can imagine a hectic (if not busy) design, with intensely saturated colors vying for your attention and multiple complementary colors creating visually vibrating perceptions.

The entire poster should be jarring to the eye, yet it appears only as a coordinated, intense image that leads your eyes comfortably around the page. This in itself attests to the quality of EPSON’s SureColor P-Series printers, in ways the specification sheet by itself cannot do.

The Specification Sheet

That said, it really does help to review the specs, once you have seen the results with your own eyes.

In this case, I’m only going to focus on those few specifications I think have the most immediate effect on the visual quality of the printed product. I would say these include the kind of inks used and the well-rounded ink colorset.

First of all, this is pigment ink. Pigment ink is different from the dye-based ink in a desktop inkjet printer. Pigment ink holds particles of the coloration material in a “suspension” between molecules of the liquid (the medium) in the ink.

In contrast, in dye-based ink the colorant is completely dissolved into a water-based vehicle.

At an earlier point in its development, dye-based ink was more vivid than pigment ink, but a single drop of water could destroy a print. It was also not as lightfast as pigment ink. In contrast, pigment ink was more lightfast and durable, but colors were not as vibrant as dye-based ink.

So it was a trade-off.

But now the technology has improved, and the two options are more similar (in terms of durability, lightfastness, and color intensity). But pigment ink is still considered slightly better for professional quality work, and that’s exactly what these EPSON SureColor P-Series printers use.

Now, the inkset. More than anything else, the selection of inks makes a huge difference. The UltraChrome PRO inkset includes the following:

1. 1. Process colors: Cyan (both Cyan and Light Cyan), Magenta (both Vivid Magenta and Vivid Light Magenta), and Yellow. So that’s five in total.

1. The inkset also includes a number of black and gray inks: Photo Black, Matte Black, Gray, Dark Gray, and Light Gray. That’s another five, or ten total.

Let’s start with the black inks (Photo Black and Matte Black). Together these allow for more contrast in black and white prints (by themselves or anywhere else on the custom printing press sheet). They also allow for sharper images.

To put this in context, about 20 years ago as a graphic designer I had to sacrifice detail in a black and white imagery on a commercial printing press: in the highlights, midtones, or shadows.

If this wasn’t acceptable, I could add an additional color (to create a duotone) or I could print a four-color process black and white image (it looked like a black and white image, but it was created with cyan, magenta, yellow, and black halftone screens).

The latter cost a lot, but it captured detail in all levels of the image, from the highlights to the midtones to the shadows. It is my understanding that the EPSON inkjet equipment achieves essentially the same effect by including a number of different tones of both black and gray.

Now, for the color. Four color process inks have a smaller color gamut (universe of printable colors) than you can reproduce with additional PMS colors or than you can reproduce on a computer screen using RGB (red, green, blue) light instead of ink.

By adding extra colors to the original CMYK inkset, manufacturers of high-end inkjet equipment, such as EPSON, can dramatically expand the printable color gamut; provide fully saturated, intense color; and match most PMS colors.

All of this can be achieved without the extra press units (and their associated costs) that you would need to do the same thing with offset commercial printing technology.

What You Can Learn From This Promotional Piece

First of all, it never hurts to request information from vendors (not just from printers but from press manufacturers, finishing product manufacturers, or any other equipment manufacturers). Usually (depending on the format of the vendor’s promotional piece) you can not only learn about the technology involved, but you can also see in the advertising material exactly how the equipment will enhance your commercial printing work.

This entry was posted on Monday, November 23rd, 2020 at 4:34 pm and is filed under Inks. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.