Re: sodium citrate, ammonium citrate, bleeding of borders

Clay,
Doh! I pulled out my pH meter.

My am citrate is 4.8 pH, my sod citrate is 7.1. What might I interpret from
that as far as bleeding is concerned?
Chris

----- Original Message ----- .
From: <wcharmon@wt.net>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, July 24, 2006 9:37 AM
Subject: Re: sodium citrate, ammonium citrate, bleeding of borders

> I'll jump in here. The acidity influences the clearing of residual ferric
> oxalate from the paper. If your clearing baths are at all basic, you risk
> creating insoluble iron that gets locked into the fibers of the paper. My
> water here in Houston in the summer has a pH of 7.8 to 8.0. I noticed that
> I
> was having a difficult time in clearing prints if I dropped them into a
> plain
> water bath right after the developer and right before the first clearing
> bath.
> So my procedure now is to put my prints straight into a bath of citric
> acid
> directly from the developer. My clearing problems went away completely.
>
> The relevance here is that if your developer has a pH above 7.0, you risk
> creating the same clearing problem with the developer.
>
> Clay
>
> Quoting "Christina Z. Anderson" <zphoto@montana.net>:
>
>> Sandy,
>> In what way does the acidity have a big impact on printing? In the way
>> the
>> print looks finally or in the way it processes? I think a while back you
>> had
>>
>> said that you get staining if the developer does not stay acid but I am
>> not
>> seeing that happen.
>>
>> BTW, Sam also told me you've tested am and sod side by side and may know
>> the
>>
>> speed/dif between the two. Does your result match mine--sod being a bit
>> lower contrast, 1/4 stop slower maybe at most, and a bit yellower in
>> tone?
>> Chris
>>
>> >I use sodium citrate for printing kallitype, and sometime with
>> > palladium (though for palladium I prefer potassium oxalate). What I
>> > use is Trisodium Citrate, C6H5Na3O7, 258.07. When mixed with
>> > distilled water the resulting pH is about 7.0. I bring this down to
>> > about pH 6.0 by adding more citric acid to the mix, and this has a
>> > big impact on printing.
>>
>>
>> One could also add citric acid to an ammonium
>> > citrate solution to reduce pH.
>> >
>> > In any event, I do agree that it would be best to test these two
>> > solutions at the same pH to create a valid comparison in printing
>> > characteristics, because pH does make a big difference, and you
>> > especially want to avoid allowing the solutions to become slightly
>> > base.
>> >
>> >
>> > Sandy
>> >
>> >
>> >
>> >
>> >
>> >>Oh pooh, Roger! I threw away the jar. I knew I should've kept it.
>> >>
>> >>I got it from Tri-Ess when it was in business, but since they closed
>> >>I threw away the catalog, too, so I can't even check back. But if
>> >>someone has an old catalog of TriEss it would be in there. I know
>> >>it was written on the label, anyway.
>> >>I had no idea there were three types!
>> >>Chris
>> >>----- Original Message ----- From: "permadocument"
>> >><info@permadocument.be>
>> >>To: <alt-photo-process-l@usask.ca>
>> >>Sent: Monday, July 24, 2006 2:18 AM
>> >>Subject: Re: sodium citrate, ammonium citrate, bleeding of borders
>> >>
>> >>>Dear Chris,
>> >>>
>> >>>Can you tell us what sodium citrate you used; monosodium (pH=
>> >>>3,4-4,0),
>> >>>disodium (pH=5,0) or trisodium (pH=7,5-9,0)?
>> >>>Thanks,
>> >>>Roger
>> >>>
>> >>>--
>> >>>Roger Kockaerts
>> >>>Permadocument - pH7
>> >>>Rue des Balkans, 7
>> >>>B-1180 Brussels
>> >>>Tel.:32-2-347 66 76
>> >>>Fax: 32-2-344 43 04
>> >>>TVA: BE 0438 246 889
>> >>>web page: <http://www.permadocument.be>
>> >>>
>> >
>>
>>
>>
>
>
>
>
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Received on 07/24/06-10:03:47 AM Z