PrintHead cleaning

[George E. Cawthon]

You are right Art. A little knowledge is
dangerous. Sloppy use of language is also
dangerous and usually reflect lack of knowledge.
My argument was semantics. Compounds are not
elements and elements are not compounds and the
two do not have the same physical characteristics.

Your discussion really has nothing to do with
whether chlorine is or is not bleach. Bleach is
the common name for commercially available
solutions of sodium hypochlorite. If you want to
say that bleach is chlorine or redefine common
bleach as chlorine go ahead.

I don't see how your discussion of dissociation or
the reaction of chlorine with organic material to
form compounds is relevant to the discussion or
useful to the discussion.

As far as useful information, one would never want
to use an active oxidizing agent on any metal part
such as a print head that requires small holes of
accurate dimensions.

 

[Lou]

In this case, George, Davy is more correct that you are. Many chlorine
compounds dissociate to chlorine gas, or elemental chlorine once they
activate with water.

In the case of sodium dichloroisocyanurate being added to water, it is
rapidly hydrolysed to release free available chlorine, establishing a
complex series of equilibria involving six chlorinated and four
non-chlorinated isocyanurates. As free available chlorine is consumed by
reaction with organic material in the water, chloroisocyanurates will
rapidly dissociate and continue to release free chlorine. Conventional
chlorination of drinking-water with elemental chlorine gives rise to a
number of by-products as a result of the reaction of free available
chlorine with natural organic matter. The use of sodium
dichloroisocyanurate as a source of free available chlorine is not
expected to lead to greater production of such by-products than does the
use of elemental chlorine.

Sometimes a little knowledge is more dangerous than none at all ;-)

Art

Holy sh.. there were more big words in that post than in the last 100 I read.

Where did you learn all that stuff, much less how to spell the words? <bg>

And you must like to type too!

Lou
Education is about knowing where to look for answers.

 

[Lou]

It was copy pasted from here:
http://www.epa.gov/chemrtk/tricltrz/c14659rr.pdf.

Well I looked at that pdf and now I am even more impressed.

Lou

 

[PaulFXH]

George E. Cawthon escreveu:

You are right Art. A little knowledge is
dangerous. Sloppy use of language is also
dangerous and usually reflect lack of knowledge.
My argument was semantics. Compounds are not
elements and elements are not compounds and the
two do not have the same physical characteristics.

Your discussion really has nothing to do with
whether chlorine is or is not bleach. Bleach is
the common name for commercially available
solutions of sodium hypochlorite. If you want to
say that bleach is chlorine or redefine common
bleach as chlorine go ahead.

I don't see how your discussion of dissociation or
the reaction of chlorine with organic material to
form compounds is relevant to the discussion or
useful to the discussion.

As far as useful information, one would never want
to use an active oxidizing agent on any metal part
such as a print head that requires small holes of
accurate dimensions.

George
Your comment in the last paragraph here is the first positively-stated
information received with regard to the value, or otherwise, of
chlorine for printhead cleaning since I posted the original question
two weeks ago.
Interestingly, it actually confirms Davy's intuitive guess re nozzle
damage which lead to the detailed chemical argument in the most recent
part of this thread.
Just for completeness, can you confirm that whatever metal of which the
printhead is composed is, indeed, susceptible to oxidation by dissolved
chlorine gas (which is almost certainly the case). The reason I ask is
because stainless steel fittings in swimming pools readily withstand
the (admittedly very low) concentrations of chlorine in pool water.
Thanks
Paul

 

[milou]

Holy sh.. there were more big words in that post than in the last 100 I read.

Where did you learn all that stuff, much less how to spell the words? <bg>

And you must like to type too!

It was copy pasted from here:
http://www.epa.gov/chemrtk/tricltrz/c14659rr.pdf.

 

[Arthur Entlich]

I fully agree that use of a strong oxidizer or a very caustic solution
is likely to damage metals, especially more active types such as
aluminum and therefore they do not make for a good solvent for ink in
inkjet printers.

However, you were quick to chastise Davy in regard to his use of the
generic term chlorine and bleach, yet in this case, both common
household chlorine bleach and the compound suggested by another poster
release elemental Chlorine gas. So we are not speaking of a compound
like NaCl which takes something like electrical current to cause mild
dissociation, but compounds which are relatively unstable and easily
release elemental chlorine. In fact, equating NaCl with these compounds
is probably more inaccurate than Davy's reference to Chlorine and Bleach.

Art

 

[Arthur Entlich]

Although, as you state, stainless steel fittings survive dilute chlorine
"compounds" added to the water of swimming pools, concentrated "chlorine
compounds" of the type we have been discussing, even if the heads were
made of stainless steel, would likely cause damage to the very tiny
nozzles which are created by laser etching. It would take very little
damage to the edges of the nozzles to make for problems with the nature
of the nozzles.

Once again, I recommend against using chlorine compounds to clean Epson
print heads.

AND, just to get the sequence of events straight, here's my posting of
June 3rd:


-------- Original Message --------
Subject: Re: PrintHead cleaning
Date: Sat, 03 Jun 2006 08:04:40 GMT
From: Arthur Entlich <[email protected]>
Organization: Shaw Residential Internet
Newsgroups: comp.periphs.printers
References: <[email protected]>
<[email protected]>

I cannot recommend chlorine bleach for print heads. It is highly
corrosive, and it also very oxidating. (that was supposed to read
oxidizing) Bad for ink, bad for most metals and some plastics.

Art


It was posted BEFORE George's comments you refer to.

Chlorine thats bleach isn't it..? I would have thought it would
damage the nozzles.

Davy

=================================

 

[George E. Cawthon]

George E. Cawthon escreveu:


George
Your comment in the last paragraph here is the first positively-stated
information received with regard to the value, or otherwise, of
chlorine for printhead cleaning since I posted the original question
two weeks ago.
Interestingly, it actually confirms Davy's intuitive guess re nozzle
damage which lead to the detailed chemical argument in the most recent
part of this thread.
Just for completeness, can you confirm that whatever metal of which the
printhead is composed is, indeed, susceptible to oxidation by dissolved
chlorine gas (which is almost certainly the case). The reason I ask is
because stainless steel fittings in swimming pools readily withstand
the (admittedly very low) concentrations of chlorine in pool water.
Thanks
Paul

I don't know what metal makes up various print
heads. HP cartridges are probably stainless
steel. I barely remember the canon print head
when I installed mine, but it could be cast
aluminum.

Chlorine gas would affect most metals, but as you
stated, swimming pool concentrations would have
little affect. OTOH, Clorox straight out of the
bottle and even a fair dilution will eat up
aluminum foil, so applied to cast aluminum it
would eat into it although at a slower rate. I
think a fair assumption would be that
almost any metal that sits in a 0.5 percent (10
percent dilution of Clorox) of hypochlorite are
any equivalent chemical would damage the edges of
holes.

Besides, what would be the point of such a
solution? Solutions that contain hypochlorite or
equivalent would be valuable in dissolving organic
compounds such as proteins, not the typical
things found in ink.

 

[PaulFXH]

George E. Cawthon escreveu:

I don't know what metal makes up various print
heads. HP cartridges are probably stainless
steel. I barely remember the canon print head
when I installed mine, but it could be cast
aluminum.

Chlorine gas would affect most metals, but as you
stated, swimming pool concentrations would have
little affect. OTOH, Clorox straight out of the
bottle and even a fair dilution will eat up
aluminum foil, so applied to cast aluminum it
would eat into it although at a slower rate. I
think a fair assumption would be that
almost any metal that sits in a 0.5 percent (10
percent dilution of Clorox) of hypochlorite are
any equivalent chemical would damage the edges of
holes.

Besides, what would be the point of such a
solution? Solutions that contain hypochlorite or
equivalent would be valuable in dissolving organic
compounds such as proteins, not the typical
things found in ink.

Just to summarize where we are:
I think we can take it, therefore, that chlorine (whether as
Bleach/Javex or as Pool Additive --Chlorox) is absolutely and
confirmedly a NO-NO for printhead cleaning. It is much more likely to
damage the printhead than unblock it and would only be recommended by a
lunatic or an incompetent (or a deranged incompetent).
Salt (sodium chloride), however, while it might make the printhead
somewhat more tasty, will almost certainly do nothing to unblock it.
Thanks to everybody for your replies and interest.
Paul