Buffering systems

Discussion in 'Color: Film, Paper, and Chemistry' started by A_Caver, Feb 18, 2012.

  1. A_Caver

    A_Caver Member

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    I have noticed some formulations of first developers in reversal films use a borax/boric acid buffer system, and others use carbonate/bicarbonate. Is there much difference between these two, especially if the final product is pH balanced with NaOH?
     
  2. Rudeofus

    Rudeofus Subscriber

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    Most buffers only work within a range of useful pH values, and it appears the range of carbonate/bicarbonate is much higher than borax/boric acid, in fact they are barely overlapping. If you go outside the useful range of a given buffer by adding large amounts of alkali or acid, buffering may not be overly effective.