Understanding Air Holes in Refilled Ink Cartridges: Why Are They Necessary?

Question:

I ordered your Canon 240-241 primer from Amazon as I was starting to refill my ink cartridges. Everything has gone smoothly, and I appreciate your instructional videos—they’ve been so helpful. Thank you!

My question concerns the ventilation of refilled ink cartridges. There is much debate about leaving a small open hole in the top label for proper ink flow. However, I’ve observed that factory-new cartridges and many remanufactured cartridges don’t appear to have those little holes in their labels. Why is that? Wouldn’t these tiny air holes make the ink dry out faster?

Answer:

Factory-new and remanufactured cartridges have small air holes, though they may be too tiny to notice on first inspection. Once you place the OEM label on a genuine ink cartridge, you'll find an air hole that leads to a network of air channels. These channels enable the cartridge to vent adequately and ensure a continuous ink flow.

Why Are Air Holes Necessary?

Ink cartridges work like a carefully controlled vacuum system. When printing, ink is sucked out of the cartridge, and without vents, negative pressure will develop which would eventually stop ink flow altogether. This air provides for the air volume that is pre-empted by the volume of ink used in the ink cartridge.

The hole in refilled cartridges should be big enough to allow for adequate airflow but not so big that the fluid evaporates too quickly. Whereas factory-sealed cartridges have air channels manufactured to precise dimensions, refilled cartridges often need an intentionally punched hole in the top to do so.

Will the Air Hole Cause Ink to Dry Out?

Yes, an air hole exposes the ink to air, which causes gradual evaporation. However, the speed of evaporation is slower than many people think. Remember: OEM cartridges are often usable for multiple years before drying up. The sponge within the cartridge holds the ink through surface tension, which helps slow rapid evaporation. In my experience, I leave the hole completely open when refilling, and the ink stays suitable for a while.

The ability to seal the top of the cartridge after it's been refilled is more of a comfort thing than it is a functional thing. Some users like to cover the hole with tape or a sticker to limit evaporation, but that's not necessary (as long as the cartridge has enough air when you carry it), so it shouldn't be a problem.

Final Thoughts

Dealing with laser printer issues and refilling ink can be complicated and require physical effort. Due to the technical nature of these problems, remote troubleshooting or repair support cannot be provided. However, we provide physical evaluation and repair services at our local diagnostic center. Print Services: BCH Technologies Printer Repair. You can read more about this service at BCH Technologies Printer Repair (https://bchtechnologies.com/printer-repair-service), so contact us because we are operating on a first-come, first-served basis due to high demand and there may be a wait to inspect your printer.

If you need more direction, I recommend using the online self-help resources to research. Begin at our YouTube channel front page (https://youtube.com/@bchtechnologies). You can also enter topics into the search icon next to the "About" section on the menu bar that deals with this type of video. As we have produced videos for nine years, this is the quickest way to find related content. YouTube’s algorithm might also recommend videos from other channels that might help you.

Thanks again for your inquiry and for supporting BCH Technologies. We appreciate your engagement, and we're always more than happy to answer any questions you may have in the future!