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US 5,688,635 AGranted
Toning of photographic print material
AssigneeIlford Limited
InventorsMichael John Parker, Anthony Martin Lannon
Life of this patent
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Abstract
There is described a photographic developing solution which comprises as an image toning agent a compound of formula I: ##STR1## where Ar is an aromatic or heteroaromatic ring which may be substituted, in a concentration of at least 0.00035 moles/liter.
Claims11
A photographic developing solution which is characterised in that it comprises as an image toning agent a compound of formula I:
- ##STR8## where Ar is a phenyl ring which is substituted with a water solubilizing group selected from the group consisting essentially of a carboxylic acid group, a sulphonic acid group or a salt thereof, in a concentration of at least 0.00035 moles/liter.
Dependencies are inferred from the claim text.