How to Clean Inkjet Cartridges

Inkjet cartridges can represent a significant expense for businesses large and small.   Investing in an ultrasonic cleaner system might prove practical to refurbish inkjet cartridges after which they can be refilled using widely available cartridge refill kits.  Cleaning inkjet cartridges is fast, safe and thorough with ultrasonic cavitation produced in tabletop ultrasonic cleaners such as the Elmasonic Select series available from Tovatech.

The process is faster than soaking the cartridge print heads in a hot water and rubbing alcohol mixture then blotting them dry.  The ultrasonic cleaning cycle can be as short as 3 to 5 seconds but may take longer if the cartridge jets are clogged with dried ink residues.  When cleaning is handled properly it is safer than cleaning by hand because there’s no temptation to use brushes on the print head surface. It is thorough because cleaning action penetrates openings that cannot be reached by simply soaking and brushing the cartridge.

How Ultrasonic Cavitation Works

Cavitation is the implosion of millions of minute bubbles created in the cartridge cleaning bath by ultrasonic transducers attached to the underside of the cleaning tank.  Powered by generators they vibrate at frequencies measured in kilohertz (kHz) or thousands of cycles per second.  Transducers on the tanks of the Elmasonic units mentioned above operate at 37 kHz.  When bubbles contact the surface of the jets they implode and quickly carry away ink residues.

A Representative Inkjet Cartridge Cleaning Procedure

We stress representative cleaning procedure because situations vary depending on the manufacturer, condition, size and number of cartridges you are cleaning.  This you will develop from experience and recommendations from the cartridge manufacturer.   For example, if you have a clogged cartridge with ink in the reservoir you should first suction it out.

For this representation we select the 0.8-liter (0.85-quart) Elmasonic S10H cleaner equipped with a heater and timer along with what is called the “Sweep” function.  Sweep is important because it provides homogeneous distribution of cavitation energy throughout the bath to promote uniform cleaning.

1. Add distilled water to the ultrasonic cleaner tank until it is about 2/3 full.   Note that the proper liquid level is critical to the reliable operation of the ultrasonic cleaner.  This must be balanced against point 3 below.
2. Set the cleaner’s thermostat to 50⁰C and turn the unit on in Degas mode to drive off drive off trapped air in the distilled water. This should take less than 10 minutes and must be done each time you fill the tank with fresh liquid.
3. Place the inkjet cartridge(s) in the cleaning basket jet-side down.  If you do more than one take care that they do not come in contact with each other.  Lower the basket into the water to immerse the cartridges to ¼ or ½ inch.  Remember you are cleaning the jets, not the entire cartridge. Tip: If the cartridges will be immersed beyond the recommended depth place spacers under the basket handles.
4. Set the timer for 1 minute.  Actual cleaning time may be less and depends on the condition and number of cartridges being cleaned.  As suggested above, with experience you’ll develop your own procedure.

At the end of the cycle remove the cartridges and blot dry.  They should now be ready to be refilled.

Empty the ultrasonic cleaner tank into a drain and rinse it with fresh water.  Prepare and degas a fresh bath and you’re ready for the next batch of cartridges.

Questions? Contact the ultrasonic cleaning pros at Tovatech for more information on equipment selection and operating suggestions.