Improvements in or relating to the production of coloured photographic images

1 - Hydroxy - 21-cetoxy-41-sulpho-2-naphthanilide is prepared by refluxing 1-amino-2-cetoxy-benzene-5-sulphonic acid (see Specification 663,005) with 1-hydroxy-2-naphthoyl chloride (from 1-hydroxy-2-naphthoic acid and thionyl chloride) in dioxane. Sulphonation of the product with 98% sulphuric acid at 70 DEG C. gives 1 - hydroxy - 4 - sulpho - 21 - cetoxy - 41 - sulpho - 2 - naphthanilide. 1 - Hydroxy - 4 - bromo - 21 - cetoxy - 2 - naphth-anilide is prepared by melting 2-cetoxy-aniline with 1 - hydroxy - 4 - bromo - 2 - naphthoic acid phenyl ester at 130 DEG C. in vacuum, and distilling off the phenol formed. Sulphonation of the product with conc. sulphuric acid gives 1 - hydroxy - 4 - bromo - 21 - cetoxy - 41 - sulpho - 2-naphthanilide. 1 - Hydroxy - 4 - bromo - 2 - naphthoic acid phenyl ester is prepared by adding a solution of bromine in acetic acid to phenyl 1-hydroxy-2-naphthoate in acetic acid.