Hi

I kinda know a little about this.  The developer is in the film or paper
emulsion so it only needs activated by a liquid with the correct ph.  

The stabilizer is a lot like fixer except it doesn't need to be removed from
the paper.  The problem is, a stabilized print smells.

Most modern B&W RC paper can be processed both ways, by a developer in a tray
or activated by an activator. Although most people will use standard fix for RC
paper and have it washed because of the chemical smell.

Larry

Not sure of the exact chemical process myself, but I sure used to do a
lot of it!

Basically, the photographic paper has developer incorporated in the
emulsion. This is activated by one solution, which is then balanced off
by a second solution. I used to have a stabilization processor with
powered rollers and troughs for the Activator and Stabilizer. Drop
exposed paper in one end, and get damp but light safe prints out the
other side in a few seconds.

Of course, they were still soaked in chemicals and would eventually
fade; I believe the process was originally for newspapers and such that
needed the utmost in speed (not quality - the blacks were a little
muddy sonetimes).

You could do a conventional fix and wash within a reasonable time to
make the prints permanent. if I'm not mistaken, polycontrast RC papers
are still stabilization compatible to this day...

   Both are "rapid access" processing. Activator processing
was used for both the old stabilization process and for
modern RC papers. The paper contains a layer of developer
under the emulsion. The activator bath consists of a
buffered alkaline solution and sulfite. This activates the
developer in the paper without being exhausted itself
although it must be replenished for carryover. RC paper can
be fixed and washed so quickly that it has displace the
stabilization method. Stabilization processing eliminated
both the fixing and washing steps by treating the paper with
a substance that allowed the remaining halides to be exposed
to light and air without blackening or discoloring. Many
compounds were used but thiocyanates were common. In
principle a stabilized print is permanent but in practice
they are not unless subsequently fixed and washed.
  Some stabilization processing used developer incorporated
paper but early versions used a developer. The stabilization
process depends on their being a reserve of the stabilizer
in the paper. RC paper will not absorb enough since the only
resevoir is the emulsion itself. Fiber paper stores some
stabilizer in the support, so it can migrate up to the
emulsion with time.
  Most current RC papers have developer layers so they can
be used in rapid access processors of the activation type. A
few, notably Ilford's papers, do not. The effect of the
developer layer on normal processing is to make the image
come up very quickly and to limit the variations in
developers, that is, image tone etc., will not vary much.
They probably also extend the life of the developer but I've
no references for that. Those who wish to vary image color
with the developer should use non-developer-incorporated RC
or fiber paper. Since the stabilization process has been out
of use for a long time now developer-incorporated fiber
paper is also no longer made.
  The stabilizing agents in Agfa Sistan and Fuji Ag-Guard
are relatives of the substances used in stablization
processing.