Comparing Piezo heads with thermal inkjet heads

[OutOFtheinkwell]

Ah!, So many printers, so little time!

 

[Grandexp]

piezo heads came out of industrial processes where they are better suited for continuous duty and more tolerant of variances. They are not suited very well for start and stop short burst printing where they are more wasteful of ink because of the requirement to maintain a proper meniscus on the nozzle. Maintenance routines on these require a fair amount of ink depending on the internal volume within the head.

Are this your opinion or real knowledge? Epson print heads are born to waste more ink than thermo print heads. Piezo force is much smaller then bursting ink bubbles by heating. Piezo head require constant priming even during a printing job to keep the ink flowing. Continuous stop and go printing or not makes no difference. Piezo heads need priming pretty much once every 1/4 or 1/2 inch of printing. Thermo heads do it every several sheets of printing.

Thermal heads will undergo more wear and are less tolerant of varying conditons but the ability to keep the nozzle wetted ready for printing is better. As a result it wastes less ink in stop and start printing operation and maintenance routines.

There is virtually no wear in thermo print heads. It is the ink that is cooked, fried, baked in the nozzles that destroys it.

The piezo head is not as accessible as a thermal head generally. Any real deep clogs in a piezo head is subject to luck in clearing it and lots of it. ( In industrial continuous processes, there are no clog issues) Thermal heads should be considered a consumable if the print load is significant.

It is Epson that makes its print heads inaccessible. There are industrial machines with removable piezo heads. Piezo print head clogs even in industrial continuous processes. I have seen an industrial printing machine with a piezo print head cleaning mechanism that used a cleaning agent, instead of ink, and fired the print head continuously for a couple of minutes to clean. The printer was an solvent based ink printer.

Pros and cons of both depending on the required application really. If I was printing a little at a time and have extended periods of no printing, I would not recommend a piezo head. For lots and lots of daily printing, the piezo head might be a good candidate.

The concept of piezo being more industrial and thermo more consumer grade is a false illusion. HP makes and sells more industrial large format printers. Their print heads are thermo heads. They are very durable. Thermo heads are desired if you want the printing speed they offer.

 

[thanhhuy123]

For consumer, family printers:

Piezo printhead: more CISS friendly, a little bit slower, accept wider range of ink type, more expensive.

Themal printhead: less CISS friendly, a little bit faster, accept narrow range of ink type, cheaper.

This's my own comparison!

Anyway, I'm using HP, and when it dies out, I might try a piezo tech printer! (Just because in my country, refill ink for Epson is ubiquitous, whereas HP and Canon are way too difficult to find.)

 

[websnail]

Piezo printhead: more CISS friendly, a little bit slower, accept wider range of ink type, more expensive.

That was once true but as discussed in relation to the newest XP600 -> 850 printers, this is no longer the case.

 

[thanhhuy123]

Piezo printhead: more CISS friendly, a little bit slower, accept wider range of ink type, more expensive.

That was once true but as discussed in relation to the newest XP600 -> 850 printers, this is no longer the case.

Oh, I don't know that. Could you please tell me in details any significant changes? Thanks.

 

[PeterBJ]

I think the reason older Epson printers are much more CISS friendly than Canon printers is not the print head technology, but the ink cartridge to the print head interface. Epson has now started to use an interface similar to that used by Canon, probably to make the new printers less CISS friendly. See this thread: http://www.nifty-stuff.com/forum/viewtopic.php?id=8871&p=1

 

[Lucas28]

Of all the pros and cons I havent seen this one:

The use of glossy pigment inks, like the popular K3 type, is only possible in piezo printers.
The reason? The resin coating on the pigment particles doesnt combine with the heat in a thermal print head. Thats why glossy pigment ink is not available for Canon printers.

So if you intend to use pigment inks, Epson is the choice.

 

[Smile]

Don't have an EPSON here but I had fixed some and the teflon coated black EPSON head seems like really old tech, like 140 nozzles per color. The Canon has 512 nozzles per color.

Now look what brother piezo head looks like
http://s10.postimg.org/qbib5tfih/brother_mfc.jpg
Really different than EPSON right, more like canon.

Ever EPSON head I saw fail was due to damage to teflon coating, the damage was by wipers that clean the head. Never had this only Canon printer, single use carts included.

 

[turbguy]

There is virtually no wear in thermo print heads. It is the ink that is cooked, fried, baked in the nozzles that destroys it.

To the contrary, EVERY FIRING OF A NOZZLE IN A THERMAL HEAD IS AN EXTREMELY VIOLENT ACTION OR ERUPTION. Not only is there inevitable thermal fatigue to the heater/electronics, and substrates, there is definite erosion to the microscopic nozzle geometry material itself. A common symptom of the latter is mis-directed droplets onto the paper, producing service test prints showing all nozzles firing, but also fine streaking in photo-printing. Piezo operation does not produce such violent localized actions, produces very little localized heating, and in my experience is MUCH more robust. The fact the there are industrial printers that use thermal heads rather than piezo probably has more to do with patent issues and licensing, rather than reliability. Thermal print heads are a "user replaceable" part an such machines, as they are in practically all consumer machines.

Wayne

 

[Smile]

I think I read that you can damage piezo head (EPSON) very easily if you do multiple deep cleanings in row like 15-25 cleanings. Perhaps the piezo transducers overheat, you know like in ultrasonic bath (you can't run those without water).

And bad CIS systems result in piezo head failues too, since mostly everyone is using CIS from china on EPSON that is. If a printer using piezo is used with bag type carts like EPSON, I'm sure it will outlast any canon printer but head replacement will be 2x more than canon. Just confirmed this on 4700D head vs. L800 piezo head.