Re: reversal bleach in SF

From: Dan Baker (email suppressed)
Date: Thu Nov 30 2006 - 21:43:50 PST


Thanks for the link and the info. The problem isn't so much finding the
materials, but finding someone who would ship them.

dan

On 11/30/06, Ed Inman <email suppressed> wrote:
>
> All B&W bleaches contain hazardous chemicals and should be mixed and
> handled by properly trained individuals with due care. The formula for R-9
> (orange) bleach is not terribly difficult, however:
>
> Per one liter of water add 9.5 grams of Potassium Dichromate and
> 12 ml of concentrated Sulfuric Acid (or 25 ml of the 48 percent sulfuric
> acid as sold by Photographers Formulary). Always add acid to water--NEVER
> water to acid. Once exhausted, bleach solution should be discarded as
> hazardous waste.
>
> One source for the chemicals (and about any other photo chemical you could
> ever want:
> www.photoformulary.com
>
> It is not generally illegal to ship chemicals for photochemistry purposes
> but extra charges may apply and the company will require you to fill out a
> DEA form stating your intended use (and require you to provide a scan of
> your current ID) before they will ship the acid. The form is provided at
> their website.
>
>
> -----Original Message-----
> >From: Scott Stark <email suppressed>
> >The orange reversal bleach must be made from
> >scratch... The Art Institute does it this way as Kodak
> >stopped making it. It has both sulfuric acid and and
> >potassium dichromate-nasty chemicals. I believe that
> >it might be possible to purchase these on Ebay, but it
> >can probably be purchased from several chemical
> >companies. The problem is shipping... it might
> >actually be illegal to ship hazardous chemicals such
> >as these by post...
>
>
> __________________________________________________________________
> For info on FrameWorks, contact Pip Chodorov at <email suppressed>.
>

__________________________________________________________________
For info on FrameWorks, contact Pip Chodorov at <email suppressed>.