Method of stabilizing organic substrate materials including photographic dye images to light and a photographic material so stabilized

DETAILED DESCRIPTION OF THE INVENTION The above-described objects and other objects of the present invention are attained by making coexist with the organic substrate material having an absorption maximum in the wavelength region of about 300 nm to about 800 nm at least one metal complex salt represented by the following general formula (I): ##STR2## wherein Cat represents one divalent cation or two monovalent cations, and n is 1 when Cat is a monovalent cation and 2 when Cat is a divalent cation.
The terms "in the presence of" or "coexistant with" as used in the specification refer not only to co-existence of the substrate material and the compound of the formula (I) in the same solution, dispersion, emulsion or layer but also to the existence of the organic substrate and the complex in, for example, adjacent layers of a multi-layered photographic material.
As long as the complex compound is associated with the organic substrate material such that it improves the light fastness of the organic substrate, it is used "in the presence of" or "coexists" with the substrate for purposes of the present invention.
The divalent inorganic cations represented by Cat in the formula (I) include alkaline earth metals such as Mg.
sup.
++, Ca.
sup.
++, Sr.
sup.
++, Ba.
sup.
++ or the like.
The divalent organic cations represented by Cat in the general formula (I) include bisonium ions (e.
g.
, a bisammonium ion, a bisphosphonium ion or the like) and so on.
The monovalent inorganic cations represented by Cat in the general formula (I) include alkali metals (e.
g.
, Li.
sup.
+, Na.
sup.
+, K.
sup.
+ or the like) and NH.
sub.
4.
sup.
+.
The monovalent organic cations represented by Cat in the general formula (I) include onium ions (e.
g.
, a quaternary ammonium ion, a quaternary phosphonium ion, a tertiary sulfonium ion or the like) and so on.
Preferred examples of the above-described onium ions include those which are represented by the following general formulae (IIa), (IIb), (IIc), (IId) and (IIe): ##STR3## wherein R.
sup.
1 to R