Color printers for the design lab

Most engineers pour their heart and soul into their work. They design, analyze, and prototype ideas, striving for perfection. But when it comes to presenting their work in print, they settle for mediocrity: simple black-and-white output. Though color prints improve comprehension and retention, people regularly tolerate black-and-white printouts because color printers have historically been slow and expensive.

It's time to change this thinking. Solid-ink technology is making color an everyday reality for any office. It has led to color printers that are productive, reliable, easy-to-use, and as affordable as black-and-white laser printers.

How it works

Think of a solid-ink printer as a digital offset press on your desktop. The heart of the printer is a full-width printhead. In contrast to disposable printheads in ink-jet printers, solid-ink printheads last the lifetime of the product. Other critical printing elements include a print drum, drum-maintenance unit, and a pressure roller. The process of creating an image on paper breaks down into three basic steps:

A drum-maintenance unit applies a microscopic layer of silicone release oil to the print drum. The drum surface is anodized aluminum, which besides being an ideal receptor for the silicone oil, is extremely hard and wear-resistant.

The printhead jets molten ink onto the rotating print drum, forming the image. The printhead is uniformly heated to hold the ink at the precise jetting temperature (about 140°C). To support 16 pages/min, the printhead is capable of jetting over 16 million drops/sec. The ink drops solidify almost instantly on the print drum, which is kept somewhat hot (about 65°C) where the ink is slightly malleable.

Paper then passes through a paper preheater and into a pressure nip formed by the pressure roller and print drum. Under heat and pressure, the image transfers from the drum onto the paper in a single pass. As the paper exits the printer, it immediately cools to room temperature and the print is ready for use. The inks are polymer based, so there are no solvents or drying time. Prints are also completely water-fast. Because the inks are not molten when they transfer to the page, the colors do not bleed and users get vivid color on nearly any paper.

Innovation of solid ink

The beauty of solid-ink printing lies in its simplicity, which starts with the ink. It's made from low-molecular-weight polymers with melting temperatures above 100°C. The four primary ink colors are formed into easy-to-load sticks or blocks. In addition to being numbered, each color is keyed to fit only in the correct slot in the printer. The environmentally friendly ink sticks are packaged in 100% recyclable material and there is nothing to spill or vacuum up.

An unusual feature of solid-ink printers is that they will accept ink at any time, even while printing. Users can "top off" all the colors to ensure uninterrupted printing. This is not possible on ink-jet or laser printers because they use cartridges, which inevitably run out in the middle of a print job.

The primary measure of printer performance is print speed. The most complete measure of print speed is "click to clunk," the time between hitting the print button and the moment the finished job hits the output tray. Most print jobs are only a few pages long, so the time it takes to print the first page is a significant factor. The combination of a color-optimized architecture and fast-image processing leads to what is perhaps the most important advantage of solid-ink printing: first-page-out in as little as 9 sec, the fastest in the industry. Moreover, solid-ink printers have a short paper path so paper travels a minimal distance. The mechanism also starts printing immediately without special synchronization.

Smarter than you think

Another feature that speeds the printing process is called Intelligent Ready. It learns a work group's use patterns by tracking when the printer is used. After a couple of weeks, adaptive algorithms know when to have the printer warmed up and ready to print. Likewise, the printer automatically goes into a low-power mode during off hours to save energy. For those who prefer to program the expected hours of operation like a programmable thermostat, that capability comes via a built-in Web server accessible by a browser.

Solid-ink technology delivers consistent quality over a printer's lifetime. This comes from the stainless-steel printhead that delivers ink to the print drum consistently year after year. A durable, anodized print drum does not degrade with use. And the single-pass-printing process is unaffected by environmental conditions such as temperature, humidity, or media type. No other desktop-printing technology is as immune to environmental and media variations. Users get consistently vibrant colors on whatever paper they choose. The efficient design of solid-ink printers allows for low acquisition and running costs. But that is not the whole story. For a printer to be truly cost effective in a busy office it must be reliable and easy to set up, use, and share.

Solid ink has a proven track record in diverse industries, including environmental, energy, financial services, legal, high-tech, small business, graphic design, advertising, and education. Businesses around the world have found that solid-ink printers have better performance and lower total cost of ownership than other color printers.