Parts of a Laser Printer Explained

Firstly, let's understand what a laser printer is and which machines this article is relevant to.

There are two main types of printer, these are based on laser or inkjet technologies. This blog is only relevant to the machines that use the laser system. Click this link if you would like to read more about the differences between the two different sorts. https://www.printright.co.uk/ink_v_laser.html

Let's familiarise ourselves with the names of the three components that every black printing laser machine needs;

Known as 'monochrome' these machines have one colour in the print process; black.

Toner - An unbelievably fine powder used in the print process, think of it as 'dry ink'.

Drum (also known as an Image Unit or Photoconductor) - the drum is a cylinder with electromagnetic properties that is used to create your image and attract toner to the paper as is passes.

Fuser - the fuser is the last stage of the laser print process, it combines 2 rollers; 1 exerting pressure and the other applying heat to the paper as it passes between them, these two forces causes the fine toner powder to be ‘fused’ into the fibre of the paper.

Now let's consider how this process gets more complex in a colour printing machine

A colour capable machine essentially has the same monochrome process of a black print machine reproduced 4 times. 4 toners, 4 drums etc.

Toners – to produce full colour prints we need, in addition to BlacK, Cyan (a bright vivid blue), Magenta (a (dusky dark red), and Yellow toners. Abbreviated frequently to CMYK.

Drums - just as there are four different colours of toner we also need four drums, one for each colour.

Transfer Belt (also known as an Image Transfer Belt or IT Belt, and Intermediate Transfer Belt) –  The surface of the belt passes across the 4 drums; cyan, magenta, yellow and black picking up each colour element of the image to make up the full colour image, before  the fuser unit fixes the image.

Fuser – No difference in the fuser unit between black and colour machines.

I can only find Toner Cartridges for my machine, why?

Some manufacturer's including HP in particular, supply only one consumable item that combines the new toner supply and a new drum unit in one integrated cartridge. Confusingly these are referred to as 'toner cartridges'  but should really be called "toner&Drum cartridges. These are undoubtedly convenient and good for maintaining optimal quality, but they are also the most expensive way to print documents.