Edgeline is a technology from HP which is based around inkjet technology in so far as it uses ink tanks (albeit on a much larger scale) and a printhead to fire the ink onto the paper. Edgeline uses a stationary printhead that spans the width of the page meaning that it can print incredibly fast. This low running cost technology is aimed at busy workgroups with a high workflow. The quality is in-between that of a laser and an inkjet.
How it works
Edgeline technology is essentially based on inkjet technology. The process has been improved to allow the high speeds that Edge line is capable of. Speeds of 50 and 60 pages per minute are achieved through these changes.
An inkjet has a printhead that moves across the width of the page creating the image, making the process a relatively slow one. Where edgeline differs is that the printhead is the width of the page, therefore the image can be created much more efficiently as the paper passes underneath it.
This then creates another issue, part of the reason that inkjets are relatively slow is that they need to allow time for the ink to dry, if your printer is running at 60 pages per minute how do you get ink dry on the page before it exits the machine?
The answer is through the use of a fifth consumable called the bonding agent. This is laid down on the page for the ink. Ink is made up of pigments suspended within a solvent. The pigment is left behind as the solvent evaporates. This however can take some time, what the bonding agent does is it causes a chemical reaction that evaporates the solvent almost instantaneously. This coupled with what are essentially 2 giant hairdryers ensure the print is dry to the touch when it exits the printer.
Since we first created this article the technology, as it often does, has moved on. HP’s range of Edgeline printers has now been discontinued and the technology has been improved and adapted for its new range of OfficeJet Pro X printers.
Unlike Edgeline, which used a separate bonding agent to rapidly dry the ink on the page, PageWide employs an “ink vehicle” contained within the ink itself. The ink vehicle contains chemicals that help control droplet size and ejection speed and which quickly evaporates once it hits the page. The pigment and ink vehicle is rapidly separated by the drying process, preventing colours from mixing and ensuring clear, sharp lines.
The most noticeable difference, though, between PageWide and Edgeline, is size. Edgeline printers were huge, expensive beasts, whereas the Officejet Pro X printers, which use PageWide technology, are small desktop printers. Even so, they’re still capable of impressive print speeds of up to 70 pages per minute.
Pagewide print heads use a system of 42,240 nozzles at a density of 1,200 nozzles per inch across the page. This ensures extremely high image quality and, unlike Edgeline, which is “in-between that of a laser and an inkjet”, Pagewide produces images equal in quality to a traditional inkjet printer.