Ink jet printing is a non-contact printing process. No printing surface such as type, plates made by photographic means, or film is needed.
Copy to be printed is prepared by computer. A minicomputer in the ink jet printer controls ink jets in the printing head. On command, microscopic droplets of ink emerge from the jets to print characters and images.
The printing head is a series of single jets. The most common used printing head has up to 1280 jets spaced at 0.0083 in.
The ink droplets are created in the system. They are either permitted to impact on the moving web of paper, or are deflected into a reservoir when no printing is desired. Deflected ink is reused. Printing is done in one pass of the paper under the ink jets.
The process, as developed by one company, is known as DIJIT (Direct image by Jet Ink Transfer). However, the most common name for it appears to be ink jet printing. Its greatest use is in direct mail printing, personalized book publishing, addressing system and proofing.