> >>Most diazo dyes are not permanent.
>
>
> I am confused about something here. Yes diazo materials tend to be
> non-perminent, but I thought the post was about diazo sensitized materials.
> Forgive me if I am wrong about that. I use diazo sensitizers to make
> emulsions containing materials that are very resilient to the effects of UV
> Light. So from my perspective, diazo is more or less permanent. I used to
> make color slides using Diazochrome, which would fade rapidly.
>
> RM
>
I don't believe that you are confused . . . the reference to diazo was
directed at their light sensitivity.
As a colored dye, diazos probably do fade but this has nothing to do with
their use as a light sensitizer in place of a dichromate.
Sincerely, Art
Art Chakalis
Columbus, Ohio, USA