What Is Fax Ink?

Fax ink is a liquid office supply that is used transfer scanned images from a facsimile transmission onto paper. Most of the time, the ink is sold in cartridges that are specially designed to fit within certain fax machines. It can be delivered as an inkjet stream, as a solid ink transfer, or as a thermal transfer. Much depends on the age and technological sophistication of the fax machine at issue. Fax ink is designed to be permanent and is often little different in form or function from the ink used in ordinary office printers.

In most fax machines, the ink cartridges sit somewhere in the innards, hidden from view but nonetheless very important to the facsimile transmission process. When someone sends a fax, he or she starts with a written or printed document that must be scanned into the sending fax machine. That machine digitizes the image and sends it out over the telephone wire to the receiving machine. Upon receipt, the receiving machine must reassemble the image and print it out, a task requiring both paper and ink.

Some of the earliest fax machines used thermal transfer paper to store and print images. Models in this style require a special sort of fax ink optimized for the very thin transfer paper. This ink is usually quite dry, and adheres to the paper primarily through heat. As the paper passes through the fax chamber and past the ink wells, it is heated on rollers, which helps the ink particles to stick and absorb.

Most modern ink-driven faxes are of the inkjet or solid ink transfer variety. Both of these models use more ink per fax than would a transfer, but the finished product is usually much sharper, crisper, and longer-lasting. In an inkjet model, the ink cartridge itself is what heats. The machine passes regular printer paper across the cartridge sensors, prompting a stream of tiny ink particles to hit the page according to a defined pattern.

Solid ink printing is similar, though the style of cartridge is very different. Cartridges designed for solid ink printing are sticks with low melting points, and often have a texture that resembles wax. When the paper passes over them, heating coils trigger the rapid melting of the ink sticks to transfer wet print to the page.

Ink cartridges are usually designed specifically for specific machines. Although ink performs the same basic function from machine to machine, cartridge types are not interchangeable. There are many types of fax ink to choose from in most places, which often makes knowing specific details and parameters an important pre-purchase step.

To replace a fax machine ink cartridge, the machine operator must usually do little more than pop open the front cover, identify the old cartridge, and remove it according to the instructions. Machines usually come with written replacement directions, but directions are often also printed on the inside of the fax cover. In some cases, the ink chambers may be in the rear of the machine.

Not all fax machines depend on fax ink. Laser printing models, for instance, generally use toner. Fax toner works a lot like ink, but is based on carbon particles, not on actual liquid or solid ink. Toner models can often go longer without a cartridge replacement, but tend to be more costly at the outset.