Solid diazo complexes

Solid diazo complexes, suitable for the preparation of photographic diazotypes, are manufactured by adding a sulphonated resinous compound to a solution of a diazotized amine. Examples describe the combination of: (1) diazotized p-diethylaminoaniline and a polymerized sodium salt of formaldehyde naphthalene sulphonic acid; (2) the diazo compound of (1) and a polymerized sodium salt of a short chain alkyl naphthalene sulphonic acid; (3) diazotized 2 : 5-dichloraniline and the resin of (1); the product, ground with sodium sulphate, gives a red dye when coupled with R salt; (4) diazotized 7-amino-2-hydroxy-4-methylquinoline and the resin of (1); the product, ground with sodium sulphate, yields an orange dye when coupled with 2-naphthol-3:6:8-trisulphonic acid; (5) diazotized p-nitraniline and sulphonated coumarone-indene resin; the product, blended with sodium sulphate, gives a red dye when coupled with R salt; (6) tetrazotized dianisidine and a sulphonated polybenzyl resin; the product couples with phloroglucinol to form a reddish blue dye. Additional sulphonated resins specified are polymerized sulphonates derived from benzene, naphthalene anthracene, diphenyl, toluene, xylene, phenol, cresol, naphthol, anisole, phenetole, resorcinol, hydroxydiphenyl and styrene.ALSO:The Specification as open to inspection under Sect. 91 comprises an example in which cotton is dyed scarlet by padding it with an alkaline solution of 2 : 3-hydroxynaphthoic acid o-anisidide and immersing it in a solution of a diazo complex from diazotized 2 : 5-dichloraniline and a polymerized formaldehyde naphthalene sulphonic acid. This subject-matter does not appear in the Specification as accepted.