Innovation has not stopped in the printing industry for over 450 years. The first 400 years saw letterpress relief imaging as the dominant process. Then in the mid-1940s we found offset lithography taking over, along with the ink and water issues to be learned by printers. Next, digital printing came in, and we saw toner-based systems replace ink on the vast majority of offset duplicator printed black-and-white work. Next, toner had started to eat into short-run four-color offset.
Now we see ink returning, this time in the form of inkjet presses. And this is where our story begins, with what just might be a major game changer for our industry, with inkjet printing taking on offset lithography. It is printing's "circle of life."
Based on Kodak's somewhat quiet and little-noticed announcement of the commercialization of its black-and-white Prosper 1000 book press last month-Offset Paperback Manufacturers will install one in its Laflin, PA plant-we will now see inkjet attack offset in book production in a big way. Kodak's Prosper press line includes a black-and-white model 1000 (our focus for this article) and also a color perfector Model 5000 XL, to be formally debuted as a commercial offering at Ipex in Birmingham, U.K. this May.
Offset Paperback Manufacturers integrated a Muller Martini Sigmaline in-line finishing system for its book printing operation in Laflin. OPM is one of the largest manufacturers of mass-market paperback books in the world, with demanding publishing clients like Random House, Pearson Education, Penguin and McGraw-Hill.
Kodak claims an "Offset Class" moniker for its Stream inkjet based Prosper line. Offset Class is defined by Kodak in the quality, economics, sustainability and reliability as compared to an offset lithographic press.
As you will see here, the Prosper 1000 book press does in fact pass this test and is therefore a front runner and game changer. No other inkjet press in the world can deliver more book pages per hour at this time. In fact, the Kodak Prosper 1000 at a 25´´ web width exceeds what other digital presses do at a 30´´ web width. Another nice feature is that the Prosper 1000 can be field upgraded to a Prosper 5000XL color pefector as customers feel fit.
The Kodak Prosper 1000 digital press is based on Kodak's patented Stream continuous inkjet print heads. These heads are assembled into linear arrays dropping over 1.7 billion controlled ink droplets a second onto either coated or uncoated paper stocks.
In today's digital press world, this compact bodied perfector press outputs a massive amount of digital printing. Running at 650 fpm (200 mpm), the Kodak Prosper 1000 press delivers pigmented nanoparticle aqueous ink (see TechWatch, GAM January 2005) onto paper at 3,600 8.5×11´´ (or A4) sized pages per minute, for a monthly duty cycle of 120 million pages per month.
As shown in the illustration here, Kodak does this in a compact, single-unit inkjet perfecting press. The print volume qualifies Kodak's Prosper 1000 press to be equivalent in function for offset press book runs up to 7,000 copies in length. Since this volume exceeds runs of the majority of book titles, by the criteria of run-length, Prosper 1000 is "offset class."
Kodak's specially designed nanoparticle inks have very unique environmental benefits. They also have engineered-in light scattering properties enhancing the appearance of the image and special properties to reduce jet orifice erosion, a major problem encountered by other forms of inkjet using pigmented inks. The Prosper 1000 delivers the equivalent of 133 lpi halftones, matching offset book quality. Kodak's ability to lay down less ink with the Stream process, yet meet the same text and halftone quality found in most books, shows an actual superiority to offset lithography, and can make books weigh less.
Greater density, lighter books
In some test comparisons against offset books, offset achieved a black optical density of 1.42, while the Kodak Prosper 1000 imaged with an optical density of 1.85, -a 30% improvement. In addition, when the page is measured in ink volumes laid down in grams per square meter, some test images of Kodak stream technology have shown 64% less weight than offset, or even lower, depending on the image. In my own water solubility tests, I have Kodak Prosper output on coated paper sitting submerged in a glass of water for three weeks now without running or streaking. In fact, ink stays on longer than paper fibers hold up.
Today an equivalent continuous-fed toner- based digital book press printing, say, 1,300 pages per minute, sells for close to the same price as the Prosper 1000 press printing 3,600 pages a minute. So Kodak produces over 2.5 times the same volume per minute. And Kodak can print the page for less, with better quality, on coated paper and with reduced environmental impact-extending inkjet's printing range into offset territory, as shown in the economic chart on p.8. If Kodak delivers as expected, this is not just a game changer, but in some areas, "game over." This is big!
