Inkjet printers have traditionally been favoured by home users for their low purchase price and by photographers and the graphics industry for their high image quality. Although usually more expensive to run than laser printers, there is a growing number of business-orientated inkjet printers available which can offer a lower cost per page than a laser printer. Lower energy consumption also makes inkjet printers an attractive proposition but they still lack the durability of laser printers when it comes to high volume printing.
How it works
An inkjet printer is a printer that places incredibly small dots of ink onto a page. By incredibly small, we are talking smaller in diameter than a human hair! An Inkjet printer is capable of placing dots extremely accurately, with resolutions in excess of 1440 x 720 dots per inch. By using combinations of the four colours Cyan, Magenta, Yellow and Black photo quality images can be created. Some manufacturers have taken this a step further and added additional colours (Light Cyan, Light Magenta, Light Yellow etc.)
There are two ways of putting ink onto the page, bubble or bubble jet and piezoelectric. Bubblejet technology uses heat and piezoelectric technology uses a crystal and an electric charge to fire the ink from the cartridge onto the page. Some inkjet printers employ a process called dye-sublimation. The ink is contained in cartridges, heated to extreme temperature, vaporized, and laid down a line at time rather a page at a time. If you look at an inkjet in action, you will see the printhead moving across the page.
There are also 2 distinct types of ink, pigment based and dye based. Both are comprised of either a dye or pigment dissolved in a solvent. When the ink hits the page the solvent dissolves leaving behind the dye or pigment. Dye based ink is water soluble, and so if the print gets wet, the ink dissolves. Pigment based inks are more water resistant and embed themselves in the fibres of the paper. Pigment based inks tend to use larger droplets, and are more fade-resistant.
Media is also a key factor in the quality of the print from an inkjet, there is a significant difference between printing onto standard media and photo media for example. You can even print directly onto CDs with some inkjets!
by Andy Leighton