Drum units and toner cartridges are two components of laser printers that in fact make the process of printing possible. However, laser printers come in several variations with different architectures. While some combine the two parts into one whole element, others use them separately. Nonetheless, knowing the difference between the two can help diagnose a problem in the machine when the printed result is just not right.
Drum vs Toner Cartridges
The difference between drum and toner cartridges is that a drum unit is an electrically charged cylinder that transfers toner particles onto a paper to construct text or images whereas a toner cartridge is a container that holds negatively charged toner particles that are attracted to positively charged image imprints in the drum unit.
A drum unit functions as a photoconductive apparatus that transfers and paints a digital image onto the surface of the paper. As it is positively charged, it attracts negatively charged toner particles from the toner cartridge to carry out this process. When the printed image or text on the paper is unclear or has strokes on it, there’s a problem in the drum unit.
A toner cartridge is a container that holds physical print medium materials. These are negatively charged toner particles that are essentially a dry powder made from plastic particles, carbon, and other colouring agents. This powder is attracted to the electrostatically charged drum unit after which it is transferred onto a paper. When the printed image or text is too light, it is time to change the toner cartridge.
Comparison Table Between Drum and Toner Cartridges
|Parameters of Comparison||Drum||Toner Cartridges|
|Meaning||A drum unit is an electrically charged cylinder that functions as a photoconductive apparatus.||A toner cartridge is a container that holds physical print medium materials.|
|Function||Its function is to attract and transfer positively charged toner particles onto a paper.||Its function is to hold negatively charged toner particles.|
|Constituents||It contains the image that is transferred via electric charge.||It contains a dry powder that is made of plastic particles, carbon, and other colouring agents.|
|When to Change||When the printout is unclear or has strokes in it, the drum unit needs to be changed.||When the printouts are coming out too light, the toner cartridge needs to be changed.|
|Cost||Drum units are costlier than toner cartridges.||Toner cartridges are cheaper in comparison with drum units.|
What is Drum?
A drum unit is a cylinder inside a laser printer that holds a positive charge. Its function is to attract negatively charged toner particles and transfer them onto the surface of the paper. Texts or images are then printed out. If the resulting print is unclear and has strokes or lines on it, it means that the drum unit of the printer needs to be changed.
The electrostatic property of the drum unit can be procured using two different methods. The first method includes using a corona wire that has an electric current running through it. The second method includes using a separately charged roller in place of a corona wire. This method is relatively newer and is gaining popularity among many laser printers of different companies.
When the drum unit has been charged and the toner particles have made their way into the drum unit, a laser beam is sent out from the printer laser scanner. This tiny beam draws patterns on the drum unit’s surface to form a text or image. The toner particles then cling to the surface of the drum while excess powder is wiped out by a drum cleaning blade.
The next step involves transferring the toner particles on the drum surface onto paper. When this happens, the toner and paper are put into a fuser roller that finally binds both. As a result, the text or image comes out as a printout on paper.
What is Toner Cartridges?
A toner cartridge is a container that holds negatively charged toner particles that are essentially the physical print medium material. These particles are a fine, dry powder made from plastic particles, carbon, and other colouring agents. They make up the actual image on the paper that is either black and white or coloured.
The toner particles are attracted to the positively charged drum unit where their electrostatic property changes. This is one reason why they can be fused onto the paper using heated rollers. Some toner cartridges are made in such a way that the drum unit is incorporated into its design. This means that if one of the two faces a problem, they must be replaced together.
However, most printers have a design where the two components are separate. In such printers, the cost of the toner cartridge is much cheaper than the drum unit. In most cases, the drum unit last three to four times longer than a toner cartridge does. Nonetheless, when a printout comes out to light and the colour is not very visible, it means that the cartridge needs to be changed.
An interesting aspect about this is that combined drum units and toner cartridges are not as sustainable or healthy for the environment. After all, if the drum unit needs to be changed every time a cartridge runs out, massive unnecessary ‘drum unit waste’ is dumped into landfills.
Main Differences Between Drum and Toner Cartridges
- A drum unit is an electrically charged photoconductive apparatus whereas a toner cartridge is a container that holds physical print medium materials.
- The function of a drum unit is to attract and transfer positively charged toner particles onto paper whereas that of toner cartridges is to hold negatively charged toner particles.
- A drum unit contains the image that is transferred via electric charge whereas a toner cartridge contains dry toner powder.
- A drum unit needs to be changed when the printout is unclear or has strokes on it whereas a toner cartridge needs to be changed when the printouts are coming out too light.
- Drum units are expensive whereas toner cartridges are comparatively cheaper.
Drum and toner cartridges are two components of a laser printer that have different functions to carry out. The function of a drum unit is to attract and transfer positively charged toner particles onto paper. On the other hand, the function of toner cartridges is to hold negatively charged toner particles. These particles change from negative to positive on reaching the drum unit.
Another major difference lies in diagnosing when either of the two needs to be changed. When the print comes out unclear or has strokes and lines on it, it means that the drum unit needs to be replaced. Meanwhile, if the print comes out to be too light, it is time to replace the toner cartridges.