On Fri, 18 Jul 2014 13:49:36 -0700 (PDT),
wrote:

I have an Hp ink jet printer that uses two cartridges. There is one three color, and one black cartridge, a number 21.
(...)

Many years ago, before cheap Chinese clone cartridges, I had a similar
problem. The problem was how to store partly used ink carts outside
of the printer. At the time, HP had a cute little plastic carrier,
that had a rubber plug over the jets, very much like what's inside the
printer. This was necessary because at the time, HP had two different
grades of carts for the printer. Users were expected to have one set
of each. Since the printer only held 1 type of ink cart at a time, a
storage carrier was needed. They came in various sizes and shapes and
worked well. Here's one example:
https://www.google.com/search?tbm=isch&q=HP+C2621-60007
Later, HP went to much simpler version, with no fancy box. Just a
plastic clip, and a rubber plug. Those did not work at all.

I reasoned that the difference between the two systems was that the
simple clip let in too much air which dried the ink, and that the cart
had to be stored upright. My "solution" was to apply a smear of
Vaseline (petroleum jelly)[1] to the jets before storage, which sealed
the jets. I was careful to store them upright, to make sure there was
ink covering the other side of the jets. For sealing and to prevent
the Vaseline from evaporating, I embalmed the cart in cellophane wrap.
I never could get any of my customers to follow my example, so I don't
know how well it might function in the field. It worked well enough
for me, where I've taken ancient used cartridges out of storage, and
they printed the first time, with no clogged nozzles.


[1] Any grease or fat will work, as long as it's sealed in cellophane
wrap. While testing, I used white grease, disc brake grease, butter,
and silicon grease. All seemed to work well, although most required a
solvent to remove. Vaseline was unique in that it will evaporate in
thin layers, which made cleaning easier.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558