Technical bulletin - 27-11-09

Ausjet Cartridge Selector:
We have spent a lot of time recently updating our cartridge selector on our website. From our cartridge selector you can find the following information :

Which cartridges are used in selected printers
Which inks, instructions, clips and seals etc we have for the cartridge you are searching for.
Photos and descriptions of products.

Its a good tool for you to easily find information about our products. I hope you make good use of it.

Procolor Pgi-520\Cli-521 Resetter available Soon:
We have just had final confirmation that the development for this Procolor resetter is now complete. This is GREAT NEWS as this means that finally a reset solution is available for your customers that use these printer models. You can now refill and reset the procolor Pgi-520\Cli-521 cartridges to fully functional with full ink levels.

Epson 73N firmware upgrade:
We have heard from various sources that Epson has released a new update with the 73n which as usual will cause a bit of havoc with compatible Epsons. Fortunately at this stage our Procolor chip seems to be handling most firmware issues quite well.

Resetting Procolor Pgi-5\Cli-8 with our Mean Green Resetter:
As well as resetting the OEM pgi-5\cli-8 range of cartridges the mean green resetter will also reset the Procolor range. A recent update to the chip on these cartridges has had the effect of a slight change to the resetter procedure. Previously when you reset the procolor cartridges the red light would stay on at the end of the reset, now the only indication of the chip been reset is that the chip light flashes once.  But don't worry, one flash indicates that the chip is reset.

From ink injection to the nozzle plate (Thermal foam based cartridges) - An Overlook On How It All Works

Ink injection:
No matter what filling equipment you use, you should aim to accomplish at least the same fill volume as the OEM cartridge. There are a number of factors that can contribute to this not occuring.
1) Speed of filling - you may be filling too quickly resulting in frothing of the ink.
2) Condition of foam - its current state - how hydrophilic the foam current is. Cleaning the foam and allowing to dry is often used to bring the foam back to a hydrophylic state.
3) Air trapped in the foam - Removal of air from the foam(vacuum filling) greatly increases the chance of filling to the correct ink volume.

Inkjet Foam(sponge):
A high percentage of all OEM cartridges on the market are foam based. In our industry many people refer to the foam as a sponge but this technically isn't correct. Over the last few years the OEM's have been (generally) producing higher density foams. If you look at different types of inkjet foams you will see that generally speaking in older foams it is quite easy to see the cell structure, whereas in more recent foams the density has increased and its almost impossible to see the cell.

The foam is also responsible for creating the backpressure (commonly referred to as negative pressure). The backpressure stops the ink from leaking. It is critical to have the right ink matched to the right foam as well. Ink has to have the right viscosity to have the correct flow rate through the foam. The correct viscosity ensures that the backpressure is not too high. Over a period of time too much backpressure will result in the ink actually been withdrawn back from the printhead into the foam.

Gauze Filter :
Before the ink passes through to the printhead area, it is important that the filter stops potentially nozzle clogging particles. The nozzle sizes these days are approx between 10-20 micron in diameter. As you can imagine, without the filter there would be lots of problems. It is also important that the filter does not have dried ink attached to it as this will restrict the flow to the prechamber which may cause flow problems during printing.

Prechamber and channels:
The prechamber is the area where the ink is pooled. Channels running from the prechamber connect with all the nozzle chambers. It is very important that the correct amount of ink is in the prechamber, as again no ink or low ink is this area may cause flow problems and ink starvation to the printhead.

This is the common reason why you can't just fill a cartridge and expect it to work. You really need to prime the printhead which pulls ink from the foam into the prechamber and into the nozzles. The same result can also be achieved by centrifugal force - a manual priming function built into a centrifuge is a big asset.

Heaters/Resistors :
For every nozzle inside the printhead there is also a heater/resistor attached to it. The heater/resistor is what causes the ink to 'jet' onto the paper. A small voltage is applied to the heater to activate that nozzle, the resistor then heats up causing a vapour bubble to be created. The expansion of the vapour bubble takes up space in the chamber displacing the ink and this forces the ink to jet out. All thermal printhead designs rely on the vapour bubble to fire the ink out of the printhead. They have varied designs with Canon calling their technology bubblejet and HP calling their's roofshooter (because it has the ability to jet upside down).

In many of the new printheads there are as many as 3000 nozzles, which means 3000 heaters/resistors in that small area. Simply amazing technology if you think about the size and the speed it all works at.

There is a number of factors which result in the failure of the heater/nozzle :
1) Age - like many electronic items - don't expect them to last forever.
2) Printing without ink firing onto the page can cause a problem - this means that ink is not filling up the nozzle chamber. This results in the heater/resistors firing but with no ink in the chamber to move the heat away will result in this area becoming hotter than expected. Nowadays printheads seem to be more tolerant to this problem than they were in earlier days, but it is quite possible that this could be weakening the resistors which could lead to an earlier failure than expected.
3) Constant creation and collapse of the vapour bubble will eventually result in the walls of the nozzle chamber breaking and damaging the heater. More and more technological advances in this area have resulted in various patented layers of materials placed between the resistor and the chamber to prevent this from happening. Recent advances have allowed longer life thermal printheads from manufacturers such as Canon, HP and Lexmark.
4) Kogation - from the japanese word 'koga' meaning biscuit. Refers to the build up that can occur on resistors over time. Too much build up may result in a weakened vapour bubble which does not produce an accurate jet or eventual failure. A good cleaning system that is not linear and can clean around corners like an ultrasonic cleaner is the best to remove kogation. It has recently been discovered than some inkjet inks may results in more kogation than others, it's another reason why you should only choose a quality ink.

With the good mark one gets from refilling inkjet cartridges, I personally cannot understand why anyone would not choose to use the best ink available to them. There are many factors that cannot be seen inside the printhead that may result in earlier failure due to not using a high quality ink which has premium components which prevent these issues. The difference in costs per refill between a premium and bodgy ink are cents. Why risk losing a customer or reducing the number of refills you can do because of a few cents per refill?

You can test the resistors by purchasing circuit testers. They will test each resistor and confirm that they are all within the correct working resistance range. This is the only way to know for sure the state of the resistors.

If a resistor has failed this means
1 Failed Resistor = 1 Failed Nozzle
A failed resistor may also cause a break in a series of resistors and could result in :
1 Failed Resistor = Many Failed Nozzles

Nozzle Plate :
The nozzle plate is the part of the printhead we see. Nozzle blockage will occur here. It's a very simple case of the water evaporating out of the ink at the nozzle position. No matter what environment you are in, evaporation will happen (even in an air conditioned office) .Depending on the formulation, water makes up 50%-70% of the ink and with the removal of water the viscosity of the ink becomes much thicker and eventually dries which causes the blockage. A longer period exposed to the environment will also result in drying of the ink in the channels, prechamber and on the filter. This will of course require more cleaning activity to get the cartridge working correctly.


I hope this information has been helpful to you.