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Chemistry for reversal processing of paper

Matt5791

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Location
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Wondering if anyone can help - I'm trying to help a customer source some chemistry in the UK for vintage Photo-booths - they probably date from the 1970's / 60's.

Currently he is using D-88 developer, R-9 bleach, CB-1 clearing bath, and thiourea toner.

Anyone encountered this chemistry?? I am told the machines apparently expose directly onto the paper and then is is reversal processed.

A strange one I know.
 
This was the normal process for Direct Positive films & papers and also used in Photobooths

Kodak D-88 - Developer for reversal processing
Sodium sulphite (anh) 45 g
Hydroquinone 22.5 g
Boric acid 5.5 g
Potassium bromide 2.5 g
Sodium hydroxide 22.5 g
Water to 1 liltre

Use full strength.
Develop Direct Positive Paper 45 seconds at 20ºC.
Rinse
Bleach for 30 seconds in R-9
Rinse
Clear in CB-1
Rinse
Re-expose
Re-devlop in T-19 or D-88
Wash, and dry.

For both Direct Positive film and Direct Positive paper, this paper was often used in Photobooths

R-9 Bleach

Water 1 litre water:
Potassium Dichromate 9.5 g
Sulphuric Acid (conc) 12 ml

(CAUTION) Always acid to water, never the other way around. Wear
eye goggles and gloves, lab coat etc.


CB-1 Clearing bath
Sodium Sulphite (anhyd) 90g
Water to 1 litre

Kodak T-19 is a Sulphide toner that was recommended for direct reversal instead of re-exposure & re-development of Direct Positive papers & films but wouldn't wouldn't be used in a Photobooth due to it's smell/odour and potential for fogging unexposed paper.. I think I've put a Reversal formula that uses an optional Thiourea redeveloper in the Film developing section here on APUG.

Ian
 
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