Printer Faults - Specks at the Top of a Page

Specks along the top of pages show some toner has got loose in the print path.

Toner at a corner of the print path might be a toner leak. However toner can also get loose from the cartridge in other ways:

  • If a paper feed error happens before the print station the toner will go onto the transfer roller instead of the page.
  • If a paper feed error happens after the print station the toner on the page is loose and will tend to tip into the printer. It will be attracted back to the transfer roller.
  • Turning a cartridge over can move some material from the waste bottle to places it should not be.
  • Media that is marginally printable might misdirect some toner into the paper path

And after all that it might just be a badly made cartridge - particularly if it's been refurbished.

Bad Cartridge.

Experience suggests that manufacturers original cartridges don't usually leak (much) toner into the printer. This clearly depends on design and on shipment care. Modern catridges tend to have lots of shipment seals that the user removes on installing a new cartridge.

It is generally good practice to inspect a cartridge when it arrives new (or refurbished. Is it in a fairly clean state? are there any visible signs of leakage?

The part of a cartridge that seems to give refurbishers most trouble is waste scraping and disposal. Print cartridges manage to transfer more than 90% of the toner placed on the OPC drum to the printed surface but that leaves some to be cleaned off. The scraper blades and guides that get toner free of the drum and travelling into the waste bottle are often a bit unsatisfactory and in a poorly refurbished cartridge they leak toner back into the print area. The toner will tend to drop near the transfer roller.

The fix is to clean the toner out. See the page on cleaning printers. Take the transfer roller out and brush it off. Turn the printer off, unplug it and clean the print path with a damp (not wet) tissue. If contamination is heavy use a brush and folded paper to lift excess toner away.

Avoid making toner airborne as it is a fine dust and should not be breathed in.

Check the underside of the cartridge because it is likely to be contaminated as well.

To find out if the problem relates to the cartridge or to something else carefully reinstall it in a clean printer and see what happens. If the cartridge stays undisturbed but the printer gets dirty again that does suggest a problem cartridge.

Problem cartridges should not be used longer than necessary to prove an issue. There is often electronics under the paper path and a buildup of toner will do it no good. Experience suggests that suppliers differ in their policy on taking back part-used toners.

Paper Jam

Surplus toner might be in the print path after a print jam, particularly if the paper jammed before the print station but the print action happened anyway. If a print action happens with no paper the print image gets dumped onto the transfer roller. If this is the case the back of the pages will be very dirty at first. This will usually clear after a few more pages have been printed.

Some printers have a cleaning mode that can be initiated from the control panel of the computer print driver. Try that.

There is at least one patent on "Image Forming Apparatus Having Biased Transfer Roller - Patent 5337127 ". In this the roller and drum voltages are switched so that the drum picks up toner from the transfer roller cleaning it for continued use.

Static Misdirecting the Paper

Specs across the whole top of the page that don't clear up imply something a bit more process oriented.

As paper gets over the transfer roller it gets a positive charge. Paper then tends to deflect upwards towards the drum attracted by the negative charge there. Ligthweight paper bends more easily and might be flicking across the bottom of the drum picking up some waste toner.

In a worse case paper will be so strongly attracted to the drum that it adheres to it and makes its way around inside the cartridge. It will be impossible to dislodge it without taking the cartridge to pieces and there probably isn't much point as the waste scraper blade will have been distorted and damged. So if the paper is lightweight and there are continual specs on the top of the page could this be the problem - if so stop using the paper because jamming paper into a cartridge will write it off.

See Cleaning)