What is a re-manufactured toner cartridge?

A re-manufactured toner cartridge is a used cartridge that has been dismantled, cleaned and rebuilt using a combination of old and new components. This differs from a re-filled toner cartridge which has not been dismantled and cleaned but simply refilled with new toner. Our discussion will focus on re-manufactured toner cartridges and will deal principally with monochrome models.

In principle, a remanufactured toner cartridge should be much cheaper than an original cartridge produced by the printer manufacturer. Many cartridge parts can be re-used and replacement parts are often reasonably priced because there is competition among after-market parts manufacturers. Some original manufacturers place very large mark-ups on their cartridge products as they have a potential monopoly on the products. They can possibly make more profit from selling cartridges than from selling the printer in the first place. Hence, most printer manufacturers do not encourage others to re-manufacture their cartridges.

Some printer manufacturers try to recover their empty cartridges not to re-manufacture them but merely to save them from landfill. Whole, empty cartridges containing a variety of steel, aluminium and plastic materials are ground into small particles for use in making “composite plastic” products such as outdoor furniture. This strategy would seem to prevent the cartridges from being re-manufactured by third parties. One might argue that re-manufacturing toner cartridges for use in a laser printer is a more effective use of resources than turning them into garden furniture or using them in landfill.

Some major printer manufacturers produce re-manufactured toner cartridges for printers produced by their competitors. Alternatively, they licence the use of their brand names for use on re-manufactured cartridges produced by third parties for use in printers made by their competitors. Admittedly, they usually impose tight quality control standards on their third party re-manufacturers. This seems to suggest that they have no objection to re-manufactured toner cartridges as such – so long as they are not competing with their own original products.

Grades of re-manufactured cartridge

Many re-manufacturers produce at least two different lines of cartridges. The product lines or families differ in terms of the number of new components that are installed as opposed to existing parts that are tested and re-used. They may also differ in terms of the starting point of the re-manufacturing process: for their top line product, they will only use empty original cartridges that have not been re-manufactured previously; their other lines may be made from cartridges that have been already been re-manufactured several times. Any new components that are used will probably differ in terms of quality and price. The product lines may also differ in terms of the quality standards that are applied in the final testing process. Lastly, there will be significant differences in selling prices between the various product lines. There is some consensus that the top-of-the-line re-manufactured product made from so-called “virgin” cartridges and containing many new as opposed to re-used components should be labelled as a premium re-manufactured toner cartridge.

Remanufacture versus refilling

Most monochrome laser printers have the toner reservoir, the imaging drum, the cleaning system and the waste toner receptacle integrated into a single, user-replaceable toner cartridge. The cartridge contains many components that wear, degrade or are consumed during printing. When the user inserts a new genuine cartridge into a printer, all these parts are effectively replaced with new ones without the need for a service call. Hence, re-filling an empty toner cartridge with new toner is not sufficient to ensure the continued proper operation of the printer. The cartridge needs to be fully re-manufactured.

Computer Chips

Over the last five to ten years, most manufacturers have installed chips on their cartridges supposedly to validate that a correctly matched, new cartridge has been installed in the printer and to enable more accurate tracking of the service life of the cartridge. These chips initially made it more difficult for after-market manufacturers to provide suitable replacement products. When a new printer model is released, it usually takes a year or so for the after-market manufacturers to develop and test suitable replacement parts and chips. The original manufacturers often release firmware updates for the printer and then some after-market chips no longer perform their intended function. New after-market chips are soon released.

Lexmark T61x and T52x cartridges showing the varying locations and designs of the chip

Most of these chips reset a page count when they are first inserted into a printer: the counter runs backward to zero and the printer will then demand the insertion of a replacement cartridge even if there is some useful life left in the old cartridge. Note how the leading edge of the different cartridges has been changed in shape: the result is that a cartridge from one model range will not fit into a later model printer.

The OPC drum

The toner cartridge contains a photo-sensitive drum, primary charging roller (not Lexmark cartridges), developing station, toner reservoir and cleaning station. The drum is an aluminium cylinder coated with a layer of non-toxic, organic-photoconductive (OPC) material. The OPC material becomes electrically conductive when exposed to light. During the printing process, a laser beam traverses the surface of the OPC drum and selectively discharges parts of the surface. It thereby composes a latent, electrostatic image on the drum. The developing process then changes the latent image into a visible image by depositing negatively charged toner particles on the exposed areas of the drum. Hence the quality of the surface of the OPC drum is a significant determinant of print quality.

The OPC drum is typically designed to last about 1.5 times the rated life of the cartridge and hence the cartridge cannot be re-used for a complete cycle unless the drum is replaced. It is conceivable that original manufacturers use such OPC drums to discourage the re-filling or re-manufacturing of their toner cartridges. After-market drums vary in quality and price: the best products last longer and produce a better image than the OPC drums used in many original cartridges. Many so-called re-manufactured toner cartridges are not fitted with a new OPC drum as this reduces the cost of manufacture. These cartridges may print quite well when first used but their print quality will gradually deteriorate as the page count rises. By the time they have printed half of their rated capacity; their print quality will probably be unacceptable.

Removing the toner barrel from a Lexmark cartridge	Removing the OPC drum in Lexmark cartridge

Primary charge roller

In Lexmark printers, the primary charge roller (PCR) is located in the printer, external to the cartridge. It is a solid rubber roller with a metal core. It is located beside the OPC drum. During the printing process, a high voltage is applied across the PCR and it rotates against the drum thereby coating the light sensitive surface with a negative electrostatic charge. The surface of the PCR will gradually be coated with a grey film of unused toner and it should be cleaned each time a new cartridge is installed into the printer. After 250,000 prints, the surface of the rubber roller can wear or be damaged by contaminants, necessitating its replacement. Any damage to the PCR can result in subsequent damage to the surface of the OPC drum since the two surfaces rotate in contact with each other.

In HP laser printers, the PCR is located inside the toner cartridge. It is also coated with conductive rubber and it must be cleaned, inspected and replaced if necessary during the re-manufacturing process.

Developer roller

Lexmark cartridges contain a solid rubber developer roller which assists the transfer of toner from the reservoir onto selected areas of the OPC drum. The roller can develop flat spots over time and this will lead to black, horizontal lines appearing on the printout about 20mm apart. The surface of the roller can also wear resulting in degradation of print quality. The developer roller needs to be carefully examined and refurbished or replaced during the cartridge re-manufacturing process.

In HP printers, the developing station consists of a metallic cylinder that rotates around a fixed magnetic core. It is usually referred to as the magnetic roller or “mag” roller. These parts also wear and need to be inspected and replaced if necessary.

Removing the toner barrel from a Lexmark cartridge		Removing the OPC drum in Lexmark cartridge

Toner

Laser printer toner is a powdery substance made of black plastic resin bound to iron particles. Over time, the unused toner in the cartridge will gradually absorb moisture from the atmosphere and this may lead the fine powder to form clumps with obvious implications for print quality. After-market toners may differ slightly in chemical composition to the original manufacturer’s formulation and hence they may not be truly compatible. For both of these reasons, it is important to remove any old, unused toner from the reservoir before any new toner is inserted.

The cartridge contains a cleaning blade which sits in contact with OPC drum. As the drum rotates during printing, excess toner is removed from the drum surface and stored in the waste toner receptacle inside the toner cartridge. This receptacle must be emptied when the cartridge is re-manufactured or it will subsequently over-fill and leak waste toner into the printer. At the same time, the cleaning blade should be replaced to ensure its surface seals well against the drum.

After all wearing parts have been cleaned, inspected and replaced if necessary, the cartridge is carefully re-assembled and any damaged seals replaced. It is then filled with an after-market toner that can vary in quality and price from one brand to another. The best after-market toners can be superior in print quality and/or coverage to the original product. The amount of toner used should be equivalent to that in the OEM cartridge: if it is less, the page yield will be less; if it is more, the toner reservoir may overflow and the cartridge will leak.

Cheaper quality toner tends to consist of more coarse particles than a first quality product and hence will not produce the same print quality. Moreover, as a cartridge is used in a printer, the finer toner particles tend to be used first thus leading to the residual toner in the cartridge reservoir becoming more coarse in texture. Hence, the print quality of a toner cartridge decreases as it is used.

Quality control

The finished product should be tested for print quality, noisy operation and leaking toner. Some of the cheaper priced manufacturers do not test their cartridges at all. Some re-manufacturers simply print a few text pages and check the quality of those. An adequate testing process should also include printing a series of all black pages to check for uniformity of coverage, blank pages to check that there is no grey back-grounding of toner, and pages of half-tones to check the quality of graphics images. Ideally, the testing process should produce at least 30 test pages composed of these different types.

Quality packaging

If it passes the quality control process, the cartridge should be stamped with the date of manufacture and any transportation aids attached. Cartridges designed for use in Lexmark S and T series printers need to have a shipping lock (usually a red plastic framework) inserted between the toner reservoir and the OPC drum to prevent damage due to vibration in transport. The exposed section of the OPC drum should be covered with a manila cardboard or foam protective strip, taped to the cartridge housing. Both of these measures will also increase the shelf life of the cartridge. It should then be sealed (usually in a black plastic bag) to prevent damage from light and moisture absorption. The cartridge should be packed in a rigid cardboard box with specially designed inserts to minimize any damage in transit to the customer.

Lexmark original toner cartridge: note the foam packing to protect the OPC drum and the shipping lock in place.

Note: Photographs used in this section have been reproduced from Recharger Magazine, October 2005 issue.