Lee, Jonathan (Jonathan.Lee@hrcc.on.ca)
Sat, 02 Oct 1999 12:58:46 -0400
Yup, it's a 20% solution.
JL
-----Original Message-----
From: Nick Makris [mailto:nick@mcn.org]
Sent: Saturday, October 02, 1999 12:54 PM
To: alt-photo-process-l@skyway.usask.ca
Subject: Re: RC negatives - stripping paper
Lee,
Does that mean that the solution is already less than a 50% solution in
strength and therefore I should try it as is?
Nick
-----Original Message-----
From: Lee, Jonathan <Jonathan.Lee@hrcc.on.ca>
To: 'alt-photo-process-l@skyway.usask.ca'
<alt-photo-process-l@skyway.usask.ca>
Date: Saturday, October 02, 1999 9:32 AM
Subject: RE: RC negatives - stripping paper
>A 5N (normal) NaOH is 200g/liter sodium hydroxide. A 50% solution is
>500g/liter. Provided that it is kept sealed, there should be no problem
>using this solution more or les indefinietly. Wear gloves and eye
>protection, lab coat if you have it. As NaOH solutions go, a 5N isn't that
>nasty or odorous but can cause skin burns.
>
>Jonathan Lee
>
>-----Original Message-----
>From: Nick Makris [mailto:nick@mcn.org]
>Sent: Saturday, October 02, 1999 12:16 PM
>To: Alt Photo
>Subject: RC negatives - stripping paper
>
>
>Hello again,
>
>Not so long ago, I read a post from Peter Fredrick regarding the removal of
>the emulsion from the paper backing of RC prints. While I have successfully
>accomplished this at times previous, he went one step further by suggesting
>the use of Sodium Hydroxide at 50% to further clear the paper.
>
>Not being very chemically minded, I have a question(s) regarding the
>strength/safety aspects of the material I have on hand. I found a plastic
>pint bottle of liquid Sod Hyd in a cupboard in my darkroom - has always
been
>in the dark. It is heretofore unopened and was manufactured in 1980. The
>strength is declared at 5.000 Normal.
>
>If you would be so kind, I would like to know, 1) if this is the same stuff
>that was recommended and is the shelf life ok? 2) use it at what dilution?
>3) besides gloves, what other safety precautions should I take??? This the
>only chemical that I have that talks about severe burns on the label,
>however, it says nothing about ventilation. I will appreciate your
>comments.
>
>Many thanks,
>
>Nick
>
>
>
>
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