| abstract |
The present invention relates to image dye-formingncouplers of formula (I)n nwhereinn R 1 is selected from an alkyl group, an aryl group,na 5-10 membered heterocyclic group containing one ornmore O, N or S atoms, each of which groups isnunsubstituted or substituted, or a substituted aminongroup; R 2 is an unsubstituted alkyl group having ansecondary or tertiary carbon atom attached to thenoxygen atom; X is hydrogen or a coupling-off group; and R 3 is a substituent and n is 0 to 4; or nwherein R 2 , as defined above, and an R 3 subsituentnmay together with the O atom form a 5-10 memberednheterocyclic group which may contain one or morenfurther heteroatoms selected from O, N and S, saidngroup being unsubstituted or substituted; and nwherein at least one of R 1 , R 2 and R 3 separately ornin combination constitutes a ballast group,nthe couplers providing enhanced light stabilityntogether with acceptable dye hue in images producednfrom photographic materials containing them. |