Inkjet Principles

Inkjet printer cartridges work on the principle of rapidly heating ink in a series of extremely fine capillary holes known as jets or nozzles that have their own individual microscopic heating elements.

As the print head moves across the page and the print paper moves forward, the data sent from the computer is converted in the printer electronics to electronically "fire" the appropriate jet element at the right time to form a bubble of ink which is deposited onto the paper to form part of a character whether it be a letter, numeral or graphic, hence the term, "bubble jet printer".

Never operate the printer when you are aware that the cartridge is empty. Expecting the print head to fire without ink is akin to boiling water dry in a saucepan and not removing the pan from the heat!

A typical cartridge may have between 48 and 128 jets and associated heating elements depending on the type and manufacturer with a capability to print 300 to 2880 plus dots per inch. The ink flowing through the rapidly heating jets is also used to cool them again ready for the next data pulse to cause them to "fire"; thereby, the correct operating temperature of each individual jet is maintained. As the ink runs out and the cartridge empties or if the cartridge has not been used for a long time and a blockage has occurred, then jet elements can burn out if the printing is continued for any length of time. This renders the cartridge useless for refilling. This condition is known as "electrically dead". This can be compared to an old style electric kettle boiling dry. The element simply burns out.

Note: with a color cartridge, one color usually runs out before the others. Do not continue printing with the remaining colors, as the jets of the one that has run out will probably burn out. In all cases of unresolved print defects, remove the cartridge and have it refilled or replace it with a new one.

Indications of ink running out or jets becoming blocked are: parts of printed characters will have lines of missing print area appearingthrough them or in extreme cases, there will be almost no sign of print on the page or in the case of printing color photographs, a sudden change of color may occur.

As soon as you observe any print defects occurring, immediately cease printing and carry out the print head cleaning procedure for one or two cycles. Carry out a nozzle or print test and repeat the clean cycle and print test, if the first attempt is unsatisfactory.

Refer to your printer operation manual for full details on how to carry out these functions. Should you still not obtain satisfactory results, the cartridge is probably empty.