The serial printing technology of ink jet printing is conceptually very similar to dot matrix - ink applied to a substrate in an up-and-down or side-by-side droplet form by pressure - however, the actual delivery method of ink jet printing differs from dot matrix substantially. Ink jet printers do not use direct pressure for the transfer process, nor do they rely on ink ribbons - instead, they use a combination of liquid ink, ultrasonic pressure and an electrostatic field. Ink jet printers create images by propelling ink into tiny, highly controlled jet streams and onto the substrate. The quality of ink jet images is determined by the size of the ink droplets - small droplets produce cleaner lines, large droplets tend to blur.

Advantages

Ink jet printing technology is virtually the only solution for direct printing on a wide variety of substrates - from cartons and cans to plastics, glass, and paper. Assembly line ink jet printing can print at extremely high speeds and code large quantities in seconds. It is the most efficient method for alpha-numerical coding of consumer goods.

Disadvantages

While ink jet printers do allow users to have more flexibility, their low image resolution, limited durability, and high unit price make them a less attractive option for bar coding purposes. Although assembly line ink jet printing services a large audience, it is a very niche application, and the printers tend to be extremely expensive. Ink jet printing is also less solvent resistant, and specialty inks are required for high speed assembly line printing - a factor which entails costly maintenance and frequent routine attention. The ability of ink jet printers to print directly on many substrates makes it a very useful printing technology; however, for bar coding projects that require quality high resolution and good durability, thermal transfer printing is by far the better choice.