Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@...> wrote:
>
> On Tue, 11 Apr 2006 20:56:25 +0200, Steve <alienrelics@...> wrote:
> 
> > No, they use a tiny resistive element.
> >
> >
> > Steve Greenfield

> 'k , that was something i suspected "back then" god knows why.
> You are positive on that?

Google is your friend.

"In a bubble jet printer, tiny resistors create heat, and this heat
vaporizes ink to create a bubble. The expansion that creates the
bubble causes a droplet to form and eject from the print head."

"The first of these technologies is called the Thermal Bubble
technology. This technology is very popular and is used by well known
printer manufacturers such as Canon as well as Hewlett Packard and
several others. The thermal bubble technology is more popularly known
as the bubble jet technology. In Ink Jet printers that use the thermal
bubble technology small resistors are used to produce heat. The
purpose of creating this heat is so that it can vaporize the ink in
order to make a bubble. When this created bubble swells up, a specific
amount of the ink is forced out of a nozzle and is put on to the page
that is being printed on. As the bubbles bursts it has the effect of
creating a vacuum. This created vacuum serves a very important purpose
in the over all printing process. The vacuum pulls some more ink from
the ink cartridge and puts it in to the print head."

"The thermal drop on demand ink jet technology is very popular. Used
by HP, Canon and others, droplets of ink are forced out of the nozzle
by heating a resistor, which causes an air bubble to expand. When the
bubble collapses, the droplet breaks off and the system returns to its
original state."

Steve Greenfield