Homebrew PCBs

Hello all,
Wondering if anyone could point me in the right direction.
To find the correct exposure time I made up a strip of inkjet
transparent film with 10 identical dill sockets plus some lines,
placed this over a strip of "fotoboard 2" board (with glass holding
it all together) and placed it under a 2* 8W uv light for between 4
and 13 mins (uncovering each dill socket every minuite). I made up
the developing solution ratio 10:1, and placed the board in a glass
dish containg developer.
After about 1 min I started to see my image appear on the board and
a bluish residue around the exposed print. This seemed ok but did
not develop any more as left it in the solution for a couple of more
mins, then the print slowely started to dissapear to nothing. I
tried etching anyway but all I got was a nice clean board striped of
all copper and no tracks/sockets at all.
At least I know how to etch the board but I am confused why the
image started to develop and then dissapeared.

In case it helps I used fotoboard 2, pcb developer and pcb etchent
from maplins ( the products are made by chiltern and I had a 1:1
ratio of etchent to water)

Any help graetfully received

Kind regards Tbone