Re: APIS, hydroquinone hardening

From: Ryuji Suzuki ^lt;[email protected]>
Date: 07/15/05-12:13:46 PM Z
Message-id: <>

From: Richard Knoppow <>
Subject: Re: APIS, hydroquinone hardening
Date: Fri, 15 Jul 2005 01:30:12 -0700

> Does this take place in any practical developer? Can you
> recommend a place to learn more about it?

Practical developers for continuous tone film development are designed
to avoid this phoenomenon. Sulfite-free developers, developers
containing developing agents/restrainers/antifoggants in amounts
away from optimal ones, etc. are easier to be influenced by this
phenomenon, but it depends on the redox overpotential of the
development condition and how the anode potential is influenced by the
oxidized developing agents being generated in that particualr
developer solution.

This type of mechanism in general (electrode process theory of
development) was studied in detail in 1970s and later. Look for
Pontius and Willis in Photogr. Sci. Eng. in 1970s and Shiao in
Photogr. Sci. Eng and J. Imaging Sci in 1980s and 1990s. (Earlier
versions of electrode process theory of development were quite
Received on Fri Jul 15 12:13:54 2005

This archive was generated by hypermail 2.1.8 : 08/25/05-05:31:51 PM Z CST