What is the reason why printer toner cartridges are not full even when they are new?

When the message 'Please replace the cartridge' appears from the printer, you have to believe the display whether the cartridge is really empty or not. When scanner manufacturer Lumafield removed toner cartridges from office printers and scanned them, it was found that the cartridges that were said to be 'empty' were not yet empty, and that the cartridges that were supposed to be new were not full.

Is this toner cartridge half empty or half full?

The inside of the toner cartridge scanned by Lumafield looks like this. The cartridge on the left is the 'empty' judgment, and the contents still remain about 15% of the tank. On the other hand, the right cartridge is a new cartridge, and it seems that the contents are only about 20% of the tank.

Inkjet printers print by spraying ink onto the paper, while laser printers spray a plastic powder called toner onto the paper.

When printing with a laser printer, the shape of the document or design to be printed is first irradiated onto a photosensitive drum charged with a laser or LED. Next, the toner is adhered to the printed pattern on the drum surface and transferred to the paper. Toner is fused to paper using heat, light, pressure, or chemical solutions.

The part of the toner cartridge that looks like an empty tank contains additives other than toner and iron developer that are necessary for these processes.

This is shown in the separated images of materials with different densities.

Shaking the toner cartridge of a laser printer that was judged to be ``empty'' may restore the remaining amount, Lumafield said, because a small amount of toner that could not be detected by the sensor was detected again. I'm explaining.