Laser printers are used by businesses to produce professional-looking correspondence, legal documents, reports, and marketing materials. A printer that is frequently used requires the replacement of two parts: the toner cartridge and the drum. Understanding what distinguishes these components allows you to maximise printer uptime and reduce maintenance costs.
A laser printer’s cartridge contains toner powder, and the printer deposits this finely divided material on the paper, forming text and graphics on the page. Toner, like ink cartridges for an inkjet printer, is a consumable item: the more you print, the more toner the printer uses. When the toner in the cartridge runs out, you replace it with a new one. Seals on the cartridge prevent toner dust from entering the print mechanism and contaminating the output.
A laser printer drum is a metal cylinder with a selenium or other photosensitive material coating on it. A mechanism inside the printer charges the drum with static electricity; then, a laser beam scans the drum’s surface, removing the static except where text is placed. Although no image can be seen on the drum, it does exist as a charge pattern. Toner powder adheres to the drum due to static electricity. The printer rolls a piece of paper against the drum, and the toner is transferred to the paper, resulting in a text-filled page.
Toner cartridge capacity is determined by the amount of toner it holds and the type of printing you do; text documents, for example, use less toner per page than graphics-heavy marketing materials. A typical cartridge holds enough toner for about 2,000 document pages; high-capacity cartridges for desktop printers last about 6,000 pages, and cartridges for high-output workgroup printers last more than 15,000 pages. The lifetime of the drum is also determined by the type of printer and the documents produced; colour graphics wear out a drum in about 5,000 pages, whereas text can produce 20,000 pages. Because drums are replaced less frequently than toner cartridges, these are typically two distinct maintenance items.
Laser printers have a single drum but multiple toner cartridges. Monochrome printers only use black toner, whereas colour laser printers use four cartridges: black, cyan, magenta, and yellow. When used in tandem, the printer generates all colours, hues, and shades of grey. The paper goes around the drum four times, once for each colour. This is why colour printing wears out the drum four times faster than plain text documents.
