A month after the announcement of the launch of its Ultrastream technology at drupa 2016, Kodak put its enterprise inkjet business on the block. The company believes Prosper, its current high speed production inkjet solution, will be best leveraged by a firm with a larger sales and distribution footprint in digital printing markets. And it expects that market opportunity for Prosper will expand even further with the introduction of Ultrastream.
Kodak says it is in talks with prospective buyers about offers to purchase its Prosper enterprise inkjet business, with its Prosper Press Platform, Prosper S Series Imprinting Systems and related products including one assumes, Stream and Ultrastream for which it is openly soliciting OEM partners. In any case, Kodak will show both Prosper and launch Ultrastream at its own stand at drupa.
At the pre-drupa press conference in Dusseldorf in February 2016, Kodak announced its next generation continuous inkjet (CIJ) Ultrastream technology that it says will move production inkjet into the mainstream of commercial printing, packaging, and more. This technology demonstrates the evolution of continuous inkjet with smaller drop sizes and precise placement accuracy for higher resolution, clean lines and enhanced definition of details. Kodak implies that this is the water-based nano-particle inkjet technology that will ultimately deliver the quality, speed and cost of offset print.
Drop generation
Described as the 4th-generation continuous inkjet (CIJ) constant-flow method for high-speed digital printing, Kodak’s Stream technology is based on precise silicon nozzles that incorporate the latest industry advances in micro electromechanical systems (MEMS) and complementary metal-oxide semiconductor (CMOS) technology, as well as a simplified and elegant electrostatic drop selection scheme. The silicon nozzle plate consists of an array of 2,560 nozzles with an approximate diameter of 9 microns positioned linearly at 600 dots per inch (dpi). Each nozzle has an annular heater positioned at the edge of the orifice.
The silicon nozzle plate is attached to a printhead manifold, which provides a constant pressure and flow rate to produce a steady ink stream. Using principles of physics, this steady stream of ink is broken into uniform droplets as each nozzle heater is activated. The frequency of heater activation is greater than 400 kHz and provides enough energy to weaken the jet filament by reducing viscosity and surface tension locally, at each orifice. Drops are then formed individually at velocities of 20 metres a second. Kodak says the low amount of energy required to create ink droplets at the surface of the nozzle is less than a 5oC temperature rise from ambient, and is 50 times lower than thermal Drop on Demand (DoD) inkjet systems, which require temperatures to reach 100o C to create nucleation of the fluid.
Ultrastream provides a proven and robust method of drop generation with a nozzle life of 3 trillion drops using low amounts of energy. The continuous inkjet drops are the same size, providing uniform character and line thickness, and enabling inherent color stability over long runs, from one press to another, and over extended periods of time.
Ultrastream technology is configured to take advantage of the industry-leading droplet generation rate to produce an image using 600 dpi in the paper cross-track direction and 1,800 dpi resolution in the paper direction, with sub 4 pico-litre droplets. This resolution equates to image quality equivalent to 1200 by 1200 dpi at speeds of over 500 feet a minute (152 metres a minute).
Nanoparticle pigment inks
In addition to precise drop generation and print selection, achieving the highest level of image quality requires Kodak’s proprietary micro-milled pigment inks. These innovative pigments produce a consistent and narrow distribution of nanotechnology particle sizes compared to conventional pigments. These environmentally-friendly water based inks use nanotechnology pigments to produce a color gamut larger than offset inks. This is achieved through the transparency of the inks, which allows light transmittance reflecting from the substrate through the ink laydown. In addition, Kodak’s pigment inks provide durability on the substrate, remain water fast, and resist color degradation from the sun’s rays for decades.
Along with Ultrastream technology, Kodak is innovating pigmented inks to expand color gamuts acheivable with 5, 6, or 7-color stations for more demanding applications. With the use of low-cost substrate treatments and chemistries developed by Kodak, it is possible to achieve a broader substrate range than most water-based pigmented inks. The low humectants in Kodak’s proprietary water-based inks enhance drying, offering better compatibility on otherwise challenging substrates. Substrates include a variety of coated and uncoated papers – including glossy as well as flexible packaging materials like oriented polypropylene and other impermeable materials like vinyl.
The company says that its pigmented inks are manufactured internally by efficient processes, leading to what it claims are the lowestcost inks on the market. In addition to its many performance benefits, Ultrastream continuous inkjet technology is said to be ‘green,’ and printhead refurbishment enables reuse of nearly all of the components in the assembly.
Robust refurbishable CIJ heads
Ultrastream technology’s reliability enables 24-hour x 7-day-a-week production. The steady state ink flow provided by continuous inkjet prevents nozzle jet-outs and clogging, enabling exceptional printhead life that is agnostic of image coverage and speed. Typical DoD systems require constant nozzle wetting, which reduces uptime and wastes ink, and inkjet heads reduce life as ink coverage and speed increases.
Compared to DoD printheads, which experience starvation or air ingestion causing a disruption in the ink flow that requires print speed adjustments, continuous inkjet delivers consistent, high-speed productivity at any coverage level. Additionally, Kodak’s proprietary nanoparticle inks offer superior color gamut and low metamerism due to the combination of transparent, nanoparticle ink layers and the closeto-ideal spectral curves of CMYK colorants.
Moreover, this technology creates uniform droplets with precise drop placement accuracy, due to high drop velocity generated through the nozzle under pressure. This allows the nozzle plate to be protected from the substrate, reducing sources of contamination that decrease printhead life. Ultrastream prints are satellite free. Unlike DoD, which prints with significant background scatter, Kodak says that Ultrastream technology print is clear and crisp with no extraneous dots.
Precise dot placement accuracy was developed to target higher-end print applications, such as magazines and catalogs. Possible industrial applications include wide format print for the home décor markets with its virtually limitless print runs and the requirement of reliable color match from lot to lot. Packaging, labels, magazines, catalogs, and home décor are examples of the known market opportunities for Ultrastream technology, whose potential benefits could extend far beyond these applications.
