Inkjet printers specialize in creating product codes that ensure traceability throughout the supply chain and communicate important information to consumers. Depending on the specific industry standard, these codes can include lot numbers, date codes, barcodes, QR codes, and others. If these codes are placed improperly or printed with error, it can cause major delays with inventory processing, impede recalls, and in certain cases, violate federal regulations.
Due to the importance of clean, clearly-legible codes, companies that use these printers need to keep them in top shape. This means regularly maintaining them, which includes frequent printhead cleanings to help avoid excess ink accumulation.
If you’re wondering how to clean your inkjet printer, or what is the best cleaning solution to use, let this article serve as your guide. Throughout this piece, we will cover what makes a solution the best printhead cleaning solution as well as describe how to clean the two major types of printheads: the sealed printheads used by continuous inkjet (CIJ) machines and the piezo printheads used by high-resolution case coders. Thermal inkjet (TIJ) printers typically use disposable printhead/cartridge assemblies and don’t need much cleaning, but we have included a note on this printer type as well.
Finding the Best Printhead Cleaning Solution for Your Printer
Although different brands of cleaning solution will slightly vary when it comes to ingredients and ingredient ratios, they are largely based on the same three components:
- Distilled water
- Isopropyl alcohol
This combination of substances is widely used due to its effectiveness in eliminating ink residue. However, different ink types have their own unique properties which affect how they accumulate and how they can be best eliminated. Accordingly, printhead cleaning solutions are specifically formulated to address certain ink types (e.g., stronger compounds are needed for solvent-based ink, while water-based ink residue can be eliminated with gentler compounds).
With these different formulations comes a necessity to be vigilant about which solutions you are putting in your printer. If a solution contains a component that isn’t compatible with your machine’s current ink and solvent, it can potentially damage the printer and bring your line to a halt. Consequently, the best printhead cleaning solution that you can choose is the one that you know will work with your printer.
Once you have found a compatible solution, the next two sections will explain how to properly clean your printhead depending on your printer type.
How to Clean a Continuous Inkjet Printhead
CIJ printers generally use sealed printheads that are covered by a sleeve. This sleeve protects the printhead’s charge electrode, phase detector, and nozzle from solvent overexposure. However, it does not protect from elements such as dried ink deposits. In these cases, manually cleaning the printhead is needed to maintain clear printing results. To demonstrate how to do this, we will detail the cleaning process using the DuraCode Industrial Printer as an example.
Begin by pressing stop on the printer’s control panel (user interface) to shut down the machine. Next, unscrew the sleeve to expose the printhead and place it in an open container or maintenance tray so that no liquid spills onto the floor during the cleaning process. While wearing eye protection, apply an appropriate cleaning solution to the printhead, directing the solution to the drop generator (nozzle), charge electrode, deflector plate, and gutter. After letting the printhead dry for a minute, wet the inside of the sleeve, place it back over the printhead, and screw it back on.
If print quality issues persist, there are two functions via the control panel (user interface) menu screen to either wash or flush the head by following the instructions provided.
With these steps, any ink blockages should be easily removed and your printer will be back to proper operation. If you still experience any issues after cleaning, seek expert guidance.
How to Clean a Piezo Printhead
Used by case coders like the Precision Series 72 and Precision Series 18, piezo-style printheads are known for their high-resolution capabilities. These resolutions are made possible by the electrically charged films within the head. The electric charge causes the film to change shape, building pressure that forces the ink onto the substrate with precise control, enabling resolutions as high as 600 x 600 DPI.
While these resolutions are higher than other printhead types can create, the piezo setup is also more prone to ink blockage. Fortunately, they are simple to clean.
Start by purging the printhead. With most case coders, this is as easy as finding “Purge Ink” in a “Service” or “Test” menu. Hold a container or paper tissue in front of the printhead to collect ink and tap “Purge.” This step cleans the nozzle of residual ink but may not remove any stubborn dried ink particles.
To help clear these stubborn particles, prime the printhead by fitting a bulb pump to the ink reservoir's opening vent knob. Hold a clean paper towel in front of the printhead and squeeze the bulb to prime it. Prime in bursts of three-to-five seconds to remove any air bubbles. Continue priming until ink is expelled into your towel. To stop priming, gently remove the bulb pump from the ink reservoir. Make sure to remove the bulb with carefully, as rough removal can cause a pressure wave within the ink tubes.
For a deeper clean after the purging and priming phases, apply cleaner to the front and the nozzle plate of the printhead. Allow the wash to flow down these surfaces, taking excess ink and particles with it. Next, clean the nozzle by using a foam swab to wipe them from top to bottom. It’s important to do this only once, as the nozzle plates are fragile and can easily be damaged. Finally, use a lint-free clean cloth to gently wipe any excessive ink/particles from the printhead housing, but make sure to NOT wipe them towards the nozzle plate.
Following these instructions, run a test print to make sure that your printer is printing at the expected resolution. If this test doesn’t deliver optimal results, seek expert guidance.
A Note on Thermal Inkjet Printheads
Thermal Inkjet (TIJ) printers are widely known for their near-zero-maintenance operation. This is because the ink cartridges used by these machines contain both the ink supply and the printhead. Accordingly, every time the cartridge is changed, there is essentially a new printhead for the machine.
If a TIJ becomes clogged with ink, fixing the issue is as simple as ejecting the cartridge, wiping it with a clean, damp cloth, letting the cartridge dry, and placing it back in the machine.
Printhead Cleaning Summary
To properly clean a printhead, you need both the right cleaning solution and the correct cleaning technique. With the right combination, you can help your printer operate at a high level for an extended time. However, the wrong solution can introduce a non-compatible element to your machine (such as the wrong solvent) which can cause damage to the system. The wrong technique can similarly damage the printhead, forcing you to buy a replacement.
To help you avoid these scenarios, our team is available to give you expert guidance whenever you need it. We’ve been working with ink for over three decades and we’re here to share our knowledge with you. Our line of cleaning solutions and wipes will keep your printer safely operating at its best.
To find the best printhead cleaning solution for your printer(s), or for any other questions related to printers and ink, contact InkJet, Inc. online or by phone at (800) 280-3245.